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SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1143 AM CDT Sat Jun 29 2024 Valid 291700Z - 301200Z ...17z Update... Minimal changes have been assessed to the current outlook. The Elevated area over portions of the eastern Great Basin has been expanded slightly to better cover the area of expected gusty winds and low RH. A few hours of gusty drainage winds are also possible across northern NV late this afternoon into the evening. However, the duration and coverage appear limited, as well as poorly overlapped with the lowest RH. Finally, an isolated thunderstorm is possible over parts of the northern Sierra this afternoon and evening, but storm coverage should be very isolated, given relatively modest moisture. Otherwise, see the previous discussion for more information. ..Lyons.. 06/29/2024 .PREV DISCUSSION... /ISSUED 0137 AM CDT Sat Jun 29 2024/ ...Synopsis... Upper ridging will develop over the central Rockies into the Plains states as a mid-level trough impinges on the Interior West today. A surface low will develop across the Great Basin, encouraging 15+ mph sustained southwesterly surface winds amid 15 percent RH by afternoon peak heating across southern and eastern Nevada into western Utah, where Elevated highlights have been maintained. Meanwhile, some mid-level moisture will accompany the western mid-level trough and overspread the Pacific Northwest and northern Rockies, especially late in the period. Mainly showers are expected, but a couple of thunderstorms cannot be completely ruled out. Given questionable receptiveness of fuels and overall coverage of thunderstorms, isolated dry thunderstorm highlights have been withheld this outlook. Finally, a surface low may develop during the afternoon across Far West Texas, encouraging dry and breezy conditions near and just west of the Trans Pecos. The potential brevity and localized nature of the dry and breezy conditions over Far West Texas preclude Elevated highlights. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

No watches are valid as of Sat Jun 29 16:45:02 UTC 2024.

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Sat Jun 29 2024 Valid 291630Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE OHIO VALLEY/MID-ATLANTIC...OZARKS VICINITY...AND THE SOUTHERN/CENTRAL HIGH PLAINS... ...SUMMARY... Damaging thunderstorm gusts and a few tornadoes appear possible today over parts of the Lower Great Lakes to upper Ohio Valley and Mid-Atlantic. Severe gusts may also be focused this afternoon and evening over the Ozarks vicinity, and the Raton Mesa and adjacent south-central High Plains. ...Lower Great Lakes and Upper Ohio Valley into the Mid-Atlantic... A loosely organized band of convection is ongoing across parts of northern/central OH. As an upper trough over the Great Lakes and eastern Canada continues to move eastward through the period, current expectations are for convection to gradually increase in coverage and intensity this afternoon across eastern OH into western PA. Recent visible satellite imagery shows substantial cloudiness across this area, which should hinder diurnal heating to some extent. Still, even modest heating of the rather moist low-level airmass should support at least weak instability by late this afternoon. Low-level and deep-layer shear appear sufficiently strong for a mix of multicells and supercells. Damaging winds will be a concern with any bowing cluster that can form and spread eastward across parts of the Mid-Atlantic through the afternoon/evening. A couple of tornadoes may also occur with any sustained supercell or embedded QLCS circulations. See Mesoscale Discussion 1472 for more details on the short-term severe threat across OH into northern WV and western PA. There also appears to be some chance for additional convection to develop along the cold front across IL/IN this afternoon, perhaps associated with a remnant MCV over eastern MO. Substantial cloudiness is present across much of this region ahead of the front. But, any thunderstorms that can form may be capable of producing isolated hail and/or strong to damaging winds. Considered including this area in a Slight Risk, but confidence remains low in robust convection persisting with eastward extent into the OH Valley in the wake of earlier thunderstorm activity. ...Ozarks... A Slight Risk for damaging winds has been introduced for southern MO, northeast OK, and vicinity. Outflow from earlier convection, along with the slowly sagging cold front, should continue southward across these areas through late afternoon while also providing a focus for additional convection. Moderate to strong instability is forecast to develop this afternoon in a narrow zone along/ahead of the front. While deep-layer shear should remain fairly modest, most 12Z guidance shows a greater concentration of robust convection developing across southern MO and vicinity late this afternoon and early evening. Loosely organized clusters capable of producing mainly damaging winds should spread generally east-southeastward through the evening. Isolated hail may also occur. ...Southern/Central High Plains... No changes have been made to the Slight Risk across the southern/central High Plains. Scattered thunderstorms are expected to develop during the late afternoon and evening in a weak post-frontal, upslope flow regime. Generally upper 50s to low 60s surface dewpoints and steep mid-level lapse rates will support a narrow corridor of moderate instability by late afternoon. While mid-level flow is expected to remain weak, vertically veering wind profiles with height through mid/upper levels will support sufficient deep shear for transient, slow-moving supercells and loosely organized clusters developing off the higher terrain of southern CO and northern NM. Occasional severe gusts appear possible with this activity as low-level lapse rates become steepened through diurnal heating. Some hail may also occur with the strongest cores. ...Michigan... Despite veered low-level winds ahead of the cold front and weak mid-level lapse rates, boundary-layer heating should yield a plume of weak instability, with MLCAPE around 500-1000 J/kg by this afternoon. Strong speed shear will support hodograph elongation. This may yield a supercell or two capable of isolated severe hail and locally strong wind gusts in the eastern U.P. into Lower MI. But, overall coverage of strong/severe thunderstorms is expected to remain rather limited across this area. ..Gleason/Thornton.. 06/29/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Sat Jun 29 2024 Valid 291630Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE OHIO VALLEY/MID-ATLANTIC...OZARKS VICINITY...AND THE SOUTHERN/CENTRAL HIGH PLAINS... ...SUMMARY... Damaging thunderstorm gusts and a few tornadoes appear possible today over parts of the Lower Great Lakes to upper Ohio Valley and Mid-Atlantic. Severe gusts may also be focused this afternoon and evening over the Ozarks vicinity, and the Raton Mesa and adjacent south-central High Plains. ...Lower Great Lakes and Upper Ohio Valley into the Mid-Atlantic... A loosely organized band of convection is ongoing across parts of northern/central OH. As an upper trough over the Great Lakes and eastern Canada continues to move eastward through the period, current expectations are for convection to gradually increase in coverage and intensity this afternoon across eastern OH into western PA. Recent visible satellite imagery shows substantial cloudiness across this area, which should hinder diurnal heating to some extent. Still, even modest heating of the rather moist low-level airmass should support at least weak instability by late this afternoon. Low-level and deep-layer shear appear sufficiently strong for a mix of multicells and supercells. Damaging winds will be a concern with any bowing cluster that can form and spread eastward across parts of the Mid-Atlantic through the afternoon/evening. A couple of tornadoes may also occur with any sustained supercell or embedded QLCS circulations. See Mesoscale Discussion 1472 for more details on the short-term severe threat across OH into northern WV and western PA. There also appears to be some chance for additional convection to develop along the cold front across IL/IN this afternoon, perhaps associated with a remnant MCV over eastern MO. Substantial cloudiness is present across much of this region ahead of the front. But, any thunderstorms that can form may be capable of producing isolated hail and/or strong to damaging winds. Considered including this area in a Slight Risk, but confidence remains low in robust convection persisting with eastward extent into the OH Valley in the wake of earlier thunderstorm activity. ...Ozarks... A Slight Risk for damaging winds has been introduced for southern MO, northeast OK, and vicinity. Outflow from earlier convection, along with the slowly sagging cold front, should continue southward across these areas through late afternoon while also providing a focus for additional convection. Moderate to strong instability is forecast to develop this afternoon in a narrow zone along/ahead of the front. While deep-layer shear should remain fairly modest, most 12Z guidance shows a greater concentration of robust convection developing across southern MO and vicinity late this afternoon and early evening. Loosely organized clusters capable of producing mainly damaging winds should spread generally east-southeastward through the evening. Isolated hail may also occur. ...Southern/Central High Plains... No changes have been made to the Slight Risk across the southern/central High Plains. Scattered thunderstorms are expected to develop during the late afternoon and evening in a weak post-frontal, upslope flow regime. Generally upper 50s to low 60s surface dewpoints and steep mid-level lapse rates will support a narrow corridor of moderate instability by late afternoon. While mid-level flow is expected to remain weak, vertically veering wind profiles with height through mid/upper levels will support sufficient deep shear for transient, slow-moving supercells and loosely organized clusters developing off the higher terrain of southern CO and northern NM. Occasional severe gusts appear possible with this activity as low-level lapse rates become steepened through diurnal heating. Some hail may also occur with the strongest cores. ...Michigan... Despite veered low-level winds ahead of the cold front and weak mid-level lapse rates, boundary-layer heating should yield a plume of weak instability, with MLCAPE around 500-1000 J/kg by this afternoon. Strong speed shear will support hodograph elongation. This may yield a supercell or two capable of isolated severe hail and locally strong wind gusts in the eastern U.P. into Lower MI. But, overall coverage of strong/severe thunderstorms is expected to remain rather limited across this area. ..Gleason/Thornton.. 06/29/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Sat Jun 29 2024 Valid 291630Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE OHIO VALLEY/MID-ATLANTIC...OZARKS VICINITY...AND THE SOUTHERN/CENTRAL HIGH PLAINS... ...SUMMARY... Damaging thunderstorm gusts and a few tornadoes appear possible today over parts of the Lower Great Lakes to upper Ohio Valley and Mid-Atlantic. Severe gusts may also be focused this afternoon and evening over the Ozarks vicinity, and the Raton Mesa and adjacent south-central High Plains. ...Lower Great Lakes and Upper Ohio Valley into the Mid-Atlantic... A loosely organized band of convection is ongoing across parts of northern/central OH. As an upper trough over the Great Lakes and eastern Canada continues to move eastward through the period, current expectations are for convection to gradually increase in coverage and intensity this afternoon across eastern OH into western PA. Recent visible satellite imagery shows substantial cloudiness across this area, which should hinder diurnal heating to some extent. Still, even modest heating of the rather moist low-level airmass should support at least weak instability by late this afternoon. Low-level and deep-layer shear appear sufficiently strong for a mix of multicells and supercells. Damaging winds will be a concern with any bowing cluster that can form and spread eastward across parts of the Mid-Atlantic through the afternoon/evening. A couple of tornadoes may also occur with any sustained supercell or embedded QLCS circulations. See Mesoscale Discussion 1472 for more details on the short-term severe threat across OH into northern WV and western PA. There also appears to be some chance for additional convection to develop along the cold front across IL/IN this afternoon, perhaps associated with a remnant MCV over eastern MO. Substantial cloudiness is present across much of this region ahead of the front. But, any thunderstorms that can form may be capable of producing isolated hail and/or strong to damaging winds. Considered including this area in a Slight Risk, but confidence remains low in robust convection persisting with eastward extent into the OH Valley in the wake of earlier thunderstorm activity. ...Ozarks... A Slight Risk for damaging winds has been introduced for southern MO, northeast OK, and vicinity. Outflow from earlier convection, along with the slowly sagging cold front, should continue southward across these areas through late afternoon while also providing a focus for additional convection. Moderate to strong instability is forecast to develop this afternoon in a narrow zone along/ahead of the front. While deep-layer shear should remain fairly modest, most 12Z guidance shows a greater concentration of robust convection developing across southern MO and vicinity late this afternoon and early evening. Loosely organized clusters capable of producing mainly damaging winds should spread generally east-southeastward through the evening. Isolated hail may also occur. ...Southern/Central High Plains... No changes have been made to the Slight Risk across the southern/central High Plains. Scattered thunderstorms are expected to develop during the late afternoon and evening in a weak post-frontal, upslope flow regime. Generally upper 50s to low 60s surface dewpoints and steep mid-level lapse rates will support a narrow corridor of moderate instability by late afternoon. While mid-level flow is expected to remain weak, vertically veering wind profiles with height through mid/upper levels will support sufficient deep shear for transient, slow-moving supercells and loosely organized clusters developing off the higher terrain of southern CO and northern NM. Occasional severe gusts appear possible with this activity as low-level lapse rates become steepened through diurnal heating. Some hail may also occur with the strongest cores. ...Michigan... Despite veered low-level winds ahead of the cold front and weak mid-level lapse rates, boundary-layer heating should yield a plume of weak instability, with MLCAPE around 500-1000 J/kg by this afternoon. Strong speed shear will support hodograph elongation. This may yield a supercell or two capable of isolated severe hail and locally strong wind gusts in the eastern U.P. into Lower MI. But, overall coverage of strong/severe thunderstorms is expected to remain rather limited across this area. ..Gleason/Thornton.. 06/29/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Sat Jun 29 2024 Valid 291630Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE OHIO VALLEY/MID-ATLANTIC...OZARKS VICINITY...AND THE SOUTHERN/CENTRAL HIGH PLAINS... ...SUMMARY... Damaging thunderstorm gusts and a few tornadoes appear possible today over parts of the Lower Great Lakes to upper Ohio Valley and Mid-Atlantic. Severe gusts may also be focused this afternoon and evening over the Ozarks vicinity, and the Raton Mesa and adjacent south-central High Plains. ...Lower Great Lakes and Upper Ohio Valley into the Mid-Atlantic... A loosely organized band of convection is ongoing across parts of northern/central OH. As an upper trough over the Great Lakes and eastern Canada continues to move eastward through the period, current expectations are for convection to gradually increase in coverage and intensity this afternoon across eastern OH into western PA. Recent visible satellite imagery shows substantial cloudiness across this area, which should hinder diurnal heating to some extent. Still, even modest heating of the rather moist low-level airmass should support at least weak instability by late this afternoon. Low-level and deep-layer shear appear sufficiently strong for a mix of multicells and supercells. Damaging winds will be a concern with any bowing cluster that can form and spread eastward across parts of the Mid-Atlantic through the afternoon/evening. A couple of tornadoes may also occur with any sustained supercell or embedded QLCS circulations. See Mesoscale Discussion 1472 for more details on the short-term severe threat across OH into northern WV and western PA. There also appears to be some chance for additional convection to develop along the cold front across IL/IN this afternoon, perhaps associated with a remnant MCV over eastern MO. Substantial cloudiness is present across much of this region ahead of the front. But, any thunderstorms that can form may be capable of producing isolated hail and/or strong to damaging winds. Considered including this area in a Slight Risk, but confidence remains low in robust convection persisting with eastward extent into the OH Valley in the wake of earlier thunderstorm activity. ...Ozarks... A Slight Risk for damaging winds has been introduced for southern MO, northeast OK, and vicinity. Outflow from earlier convection, along with the slowly sagging cold front, should continue southward across these areas through late afternoon while also providing a focus for additional convection. Moderate to strong instability is forecast to develop this afternoon in a narrow zone along/ahead of the front. While deep-layer shear should remain fairly modest, most 12Z guidance shows a greater concentration of robust convection developing across southern MO and vicinity late this afternoon and early evening. Loosely organized clusters capable of producing mainly damaging winds should spread generally east-southeastward through the evening. Isolated hail may also occur. ...Southern/Central High Plains... No changes have been made to the Slight Risk across the southern/central High Plains. Scattered thunderstorms are expected to develop during the late afternoon and evening in a weak post-frontal, upslope flow regime. Generally upper 50s to low 60s surface dewpoints and steep mid-level lapse rates will support a narrow corridor of moderate instability by late afternoon. While mid-level flow is expected to remain weak, vertically veering wind profiles with height through mid/upper levels will support sufficient deep shear for transient, slow-moving supercells and loosely organized clusters developing off the higher terrain of southern CO and northern NM. Occasional severe gusts appear possible with this activity as low-level lapse rates become steepened through diurnal heating. Some hail may also occur with the strongest cores. ...Michigan... Despite veered low-level winds ahead of the cold front and weak mid-level lapse rates, boundary-layer heating should yield a plume of weak instability, with MLCAPE around 500-1000 J/kg by this afternoon. Strong speed shear will support hodograph elongation. This may yield a supercell or two capable of isolated severe hail and locally strong wind gusts in the eastern U.P. into Lower MI. But, overall coverage of strong/severe thunderstorms is expected to remain rather limited across this area. ..Gleason/Thornton.. 06/29/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Sat Jun 29 2024 Valid 291630Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE OHIO VALLEY/MID-ATLANTIC...OZARKS VICINITY...AND THE SOUTHERN/CENTRAL HIGH PLAINS... ...SUMMARY... Damaging thunderstorm gusts and a few tornadoes appear possible today over parts of the Lower Great Lakes to upper Ohio Valley and Mid-Atlantic. Severe gusts may also be focused this afternoon and evening over the Ozarks vicinity, and the Raton Mesa and adjacent south-central High Plains. ...Lower Great Lakes and Upper Ohio Valley into the Mid-Atlantic... A loosely organized band of convection is ongoing across parts of northern/central OH. As an upper trough over the Great Lakes and eastern Canada continues to move eastward through the period, current expectations are for convection to gradually increase in coverage and intensity this afternoon across eastern OH into western PA. Recent visible satellite imagery shows substantial cloudiness across this area, which should hinder diurnal heating to some extent. Still, even modest heating of the rather moist low-level airmass should support at least weak instability by late this afternoon. Low-level and deep-layer shear appear sufficiently strong for a mix of multicells and supercells. Damaging winds will be a concern with any bowing cluster that can form and spread eastward across parts of the Mid-Atlantic through the afternoon/evening. A couple of tornadoes may also occur with any sustained supercell or embedded QLCS circulations. See Mesoscale Discussion 1472 for more details on the short-term severe threat across OH into northern WV and western PA. There also appears to be some chance for additional convection to develop along the cold front across IL/IN this afternoon, perhaps associated with a remnant MCV over eastern MO. Substantial cloudiness is present across much of this region ahead of the front. But, any thunderstorms that can form may be capable of producing isolated hail and/or strong to damaging winds. Considered including this area in a Slight Risk, but confidence remains low in robust convection persisting with eastward extent into the OH Valley in the wake of earlier thunderstorm activity. ...Ozarks... A Slight Risk for damaging winds has been introduced for southern MO, northeast OK, and vicinity. Outflow from earlier convection, along with the slowly sagging cold front, should continue southward across these areas through late afternoon while also providing a focus for additional convection. Moderate to strong instability is forecast to develop this afternoon in a narrow zone along/ahead of the front. While deep-layer shear should remain fairly modest, most 12Z guidance shows a greater concentration of robust convection developing across southern MO and vicinity late this afternoon and early evening. Loosely organized clusters capable of producing mainly damaging winds should spread generally east-southeastward through the evening. Isolated hail may also occur. ...Southern/Central High Plains... No changes have been made to the Slight Risk across the southern/central High Plains. Scattered thunderstorms are expected to develop during the late afternoon and evening in a weak post-frontal, upslope flow regime. Generally upper 50s to low 60s surface dewpoints and steep mid-level lapse rates will support a narrow corridor of moderate instability by late afternoon. While mid-level flow is expected to remain weak, vertically veering wind profiles with height through mid/upper levels will support sufficient deep shear for transient, slow-moving supercells and loosely organized clusters developing off the higher terrain of southern CO and northern NM. Occasional severe gusts appear possible with this activity as low-level lapse rates become steepened through diurnal heating. Some hail may also occur with the strongest cores. ...Michigan... Despite veered low-level winds ahead of the cold front and weak mid-level lapse rates, boundary-layer heating should yield a plume of weak instability, with MLCAPE around 500-1000 J/kg by this afternoon. Strong speed shear will support hodograph elongation. This may yield a supercell or two capable of isolated severe hail and locally strong wind gusts in the eastern U.P. into Lower MI. But, overall coverage of strong/severe thunderstorms is expected to remain rather limited across this area. ..Gleason/Thornton.. 06/29/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Sat Jun 29 2024 Valid 291630Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE OHIO VALLEY/MID-ATLANTIC...OZARKS VICINITY...AND THE SOUTHERN/CENTRAL HIGH PLAINS... ...SUMMARY... Damaging thunderstorm gusts and a few tornadoes appear possible today over parts of the Lower Great Lakes to upper Ohio Valley and Mid-Atlantic. Severe gusts may also be focused this afternoon and evening over the Ozarks vicinity, and the Raton Mesa and adjacent south-central High Plains. ...Lower Great Lakes and Upper Ohio Valley into the Mid-Atlantic... A loosely organized band of convection is ongoing across parts of northern/central OH. As an upper trough over the Great Lakes and eastern Canada continues to move eastward through the period, current expectations are for convection to gradually increase in coverage and intensity this afternoon across eastern OH into western PA. Recent visible satellite imagery shows substantial cloudiness across this area, which should hinder diurnal heating to some extent. Still, even modest heating of the rather moist low-level airmass should support at least weak instability by late this afternoon. Low-level and deep-layer shear appear sufficiently strong for a mix of multicells and supercells. Damaging winds will be a concern with any bowing cluster that can form and spread eastward across parts of the Mid-Atlantic through the afternoon/evening. A couple of tornadoes may also occur with any sustained supercell or embedded QLCS circulations. See Mesoscale Discussion 1472 for more details on the short-term severe threat across OH into northern WV and western PA. There also appears to be some chance for additional convection to develop along the cold front across IL/IN this afternoon, perhaps associated with a remnant MCV over eastern MO. Substantial cloudiness is present across much of this region ahead of the front. But, any thunderstorms that can form may be capable of producing isolated hail and/or strong to damaging winds. Considered including this area in a Slight Risk, but confidence remains low in robust convection persisting with eastward extent into the OH Valley in the wake of earlier thunderstorm activity. ...Ozarks... A Slight Risk for damaging winds has been introduced for southern MO, northeast OK, and vicinity. Outflow from earlier convection, along with the slowly sagging cold front, should continue southward across these areas through late afternoon while also providing a focus for additional convection. Moderate to strong instability is forecast to develop this afternoon in a narrow zone along/ahead of the front. While deep-layer shear should remain fairly modest, most 12Z guidance shows a greater concentration of robust convection developing across southern MO and vicinity late this afternoon and early evening. Loosely organized clusters capable of producing mainly damaging winds should spread generally east-southeastward through the evening. Isolated hail may also occur. ...Southern/Central High Plains... No changes have been made to the Slight Risk across the southern/central High Plains. Scattered thunderstorms are expected to develop during the late afternoon and evening in a weak post-frontal, upslope flow regime. Generally upper 50s to low 60s surface dewpoints and steep mid-level lapse rates will support a narrow corridor of moderate instability by late afternoon. While mid-level flow is expected to remain weak, vertically veering wind profiles with height through mid/upper levels will support sufficient deep shear for transient, slow-moving supercells and loosely organized clusters developing off the higher terrain of southern CO and northern NM. Occasional severe gusts appear possible with this activity as low-level lapse rates become steepened through diurnal heating. Some hail may also occur with the strongest cores. ...Michigan... Despite veered low-level winds ahead of the cold front and weak mid-level lapse rates, boundary-layer heating should yield a plume of weak instability, with MLCAPE around 500-1000 J/kg by this afternoon. Strong speed shear will support hodograph elongation. This may yield a supercell or two capable of isolated severe hail and locally strong wind gusts in the eastern U.P. into Lower MI. But, overall coverage of strong/severe thunderstorms is expected to remain rather limited across this area. ..Gleason/Thornton.. 06/29/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Sat Jun 29 2024 Valid 291630Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE OHIO VALLEY/MID-ATLANTIC...OZARKS VICINITY...AND THE SOUTHERN/CENTRAL HIGH PLAINS... ...SUMMARY... Damaging thunderstorm gusts and a few tornadoes appear possible today over parts of the Lower Great Lakes to upper Ohio Valley and Mid-Atlantic. Severe gusts may also be focused this afternoon and evening over the Ozarks vicinity, and the Raton Mesa and adjacent south-central High Plains. ...Lower Great Lakes and Upper Ohio Valley into the Mid-Atlantic... A loosely organized band of convection is ongoing across parts of northern/central OH. As an upper trough over the Great Lakes and eastern Canada continues to move eastward through the period, current expectations are for convection to gradually increase in coverage and intensity this afternoon across eastern OH into western PA. Recent visible satellite imagery shows substantial cloudiness across this area, which should hinder diurnal heating to some extent. Still, even modest heating of the rather moist low-level airmass should support at least weak instability by late this afternoon. Low-level and deep-layer shear appear sufficiently strong for a mix of multicells and supercells. Damaging winds will be a concern with any bowing cluster that can form and spread eastward across parts of the Mid-Atlantic through the afternoon/evening. A couple of tornadoes may also occur with any sustained supercell or embedded QLCS circulations. See Mesoscale Discussion 1472 for more details on the short-term severe threat across OH into northern WV and western PA. There also appears to be some chance for additional convection to develop along the cold front across IL/IN this afternoon, perhaps associated with a remnant MCV over eastern MO. Substantial cloudiness is present across much of this region ahead of the front. But, any thunderstorms that can form may be capable of producing isolated hail and/or strong to damaging winds. Considered including this area in a Slight Risk, but confidence remains low in robust convection persisting with eastward extent into the OH Valley in the wake of earlier thunderstorm activity. ...Ozarks... A Slight Risk for damaging winds has been introduced for southern MO, northeast OK, and vicinity. Outflow from earlier convection, along with the slowly sagging cold front, should continue southward across these areas through late afternoon while also providing a focus for additional convection. Moderate to strong instability is forecast to develop this afternoon in a narrow zone along/ahead of the front. While deep-layer shear should remain fairly modest, most 12Z guidance shows a greater concentration of robust convection developing across southern MO and vicinity late this afternoon and early evening. Loosely organized clusters capable of producing mainly damaging winds should spread generally east-southeastward through the evening. Isolated hail may also occur. ...Southern/Central High Plains... No changes have been made to the Slight Risk across the southern/central High Plains. Scattered thunderstorms are expected to develop during the late afternoon and evening in a weak post-frontal, upslope flow regime. Generally upper 50s to low 60s surface dewpoints and steep mid-level lapse rates will support a narrow corridor of moderate instability by late afternoon. While mid-level flow is expected to remain weak, vertically veering wind profiles with height through mid/upper levels will support sufficient deep shear for transient, slow-moving supercells and loosely organized clusters developing off the higher terrain of southern CO and northern NM. Occasional severe gusts appear possible with this activity as low-level lapse rates become steepened through diurnal heating. Some hail may also occur with the strongest cores. ...Michigan... Despite veered low-level winds ahead of the cold front and weak mid-level lapse rates, boundary-layer heating should yield a plume of weak instability, with MLCAPE around 500-1000 J/kg by this afternoon. Strong speed shear will support hodograph elongation. This may yield a supercell or two capable of isolated severe hail and locally strong wind gusts in the eastern U.P. into Lower MI. But, overall coverage of strong/severe thunderstorms is expected to remain rather limited across this area. ..Gleason/Thornton.. 06/29/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Sat Jun 29 2024 Valid 291630Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE OHIO VALLEY/MID-ATLANTIC...OZARKS VICINITY...AND THE SOUTHERN/CENTRAL HIGH PLAINS... ...SUMMARY... Damaging thunderstorm gusts and a few tornadoes appear possible today over parts of the Lower Great Lakes to upper Ohio Valley and Mid-Atlantic. Severe gusts may also be focused this afternoon and evening over the Ozarks vicinity, and the Raton Mesa and adjacent south-central High Plains. ...Lower Great Lakes and Upper Ohio Valley into the Mid-Atlantic... A loosely organized band of convection is ongoing across parts of northern/central OH. As an upper trough over the Great Lakes and eastern Canada continues to move eastward through the period, current expectations are for convection to gradually increase in coverage and intensity this afternoon across eastern OH into western PA. Recent visible satellite imagery shows substantial cloudiness across this area, which should hinder diurnal heating to some extent. Still, even modest heating of the rather moist low-level airmass should support at least weak instability by late this afternoon. Low-level and deep-layer shear appear sufficiently strong for a mix of multicells and supercells. Damaging winds will be a concern with any bowing cluster that can form and spread eastward across parts of the Mid-Atlantic through the afternoon/evening. A couple of tornadoes may also occur with any sustained supercell or embedded QLCS circulations. See Mesoscale Discussion 1472 for more details on the short-term severe threat across OH into northern WV and western PA. There also appears to be some chance for additional convection to develop along the cold front across IL/IN this afternoon, perhaps associated with a remnant MCV over eastern MO. Substantial cloudiness is present across much of this region ahead of the front. But, any thunderstorms that can form may be capable of producing isolated hail and/or strong to damaging winds. Considered including this area in a Slight Risk, but confidence remains low in robust convection persisting with eastward extent into the OH Valley in the wake of earlier thunderstorm activity. ...Ozarks... A Slight Risk for damaging winds has been introduced for southern MO, northeast OK, and vicinity. Outflow from earlier convection, along with the slowly sagging cold front, should continue southward across these areas through late afternoon while also providing a focus for additional convection. Moderate to strong instability is forecast to develop this afternoon in a narrow zone along/ahead of the front. While deep-layer shear should remain fairly modest, most 12Z guidance shows a greater concentration of robust convection developing across southern MO and vicinity late this afternoon and early evening. Loosely organized clusters capable of producing mainly damaging winds should spread generally east-southeastward through the evening. Isolated hail may also occur. ...Southern/Central High Plains... No changes have been made to the Slight Risk across the southern/central High Plains. Scattered thunderstorms are expected to develop during the late afternoon and evening in a weak post-frontal, upslope flow regime. Generally upper 50s to low 60s surface dewpoints and steep mid-level lapse rates will support a narrow corridor of moderate instability by late afternoon. While mid-level flow is expected to remain weak, vertically veering wind profiles with height through mid/upper levels will support sufficient deep shear for transient, slow-moving supercells and loosely organized clusters developing off the higher terrain of southern CO and northern NM. Occasional severe gusts appear possible with this activity as low-level lapse rates become steepened through diurnal heating. Some hail may also occur with the strongest cores. ...Michigan... Despite veered low-level winds ahead of the cold front and weak mid-level lapse rates, boundary-layer heating should yield a plume of weak instability, with MLCAPE around 500-1000 J/kg by this afternoon. Strong speed shear will support hodograph elongation. This may yield a supercell or two capable of isolated severe hail and locally strong wind gusts in the eastern U.P. into Lower MI. But, overall coverage of strong/severe thunderstorms is expected to remain rather limited across this area. ..Gleason/Thornton.. 06/29/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Sat Jun 29 2024 Valid 291630Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE OHIO VALLEY/MID-ATLANTIC...OZARKS VICINITY...AND THE SOUTHERN/CENTRAL HIGH PLAINS... ...SUMMARY... Damaging thunderstorm gusts and a few tornadoes appear possible today over parts of the Lower Great Lakes to upper Ohio Valley and Mid-Atlantic. Severe gusts may also be focused this afternoon and evening over the Ozarks vicinity, and the Raton Mesa and adjacent south-central High Plains. ...Lower Great Lakes and Upper Ohio Valley into the Mid-Atlantic... A loosely organized band of convection is ongoing across parts of northern/central OH. As an upper trough over the Great Lakes and eastern Canada continues to move eastward through the period, current expectations are for convection to gradually increase in coverage and intensity this afternoon across eastern OH into western PA. Recent visible satellite imagery shows substantial cloudiness across this area, which should hinder diurnal heating to some extent. Still, even modest heating of the rather moist low-level airmass should support at least weak instability by late this afternoon. Low-level and deep-layer shear appear sufficiently strong for a mix of multicells and supercells. Damaging winds will be a concern with any bowing cluster that can form and spread eastward across parts of the Mid-Atlantic through the afternoon/evening. A couple of tornadoes may also occur with any sustained supercell or embedded QLCS circulations. See Mesoscale Discussion 1472 for more details on the short-term severe threat across OH into northern WV and western PA. There also appears to be some chance for additional convection to develop along the cold front across IL/IN this afternoon, perhaps associated with a remnant MCV over eastern MO. Substantial cloudiness is present across much of this region ahead of the front. But, any thunderstorms that can form may be capable of producing isolated hail and/or strong to damaging winds. Considered including this area in a Slight Risk, but confidence remains low in robust convection persisting with eastward extent into the OH Valley in the wake of earlier thunderstorm activity. ...Ozarks... A Slight Risk for damaging winds has been introduced for southern MO, northeast OK, and vicinity. Outflow from earlier convection, along with the slowly sagging cold front, should continue southward across these areas through late afternoon while also providing a focus for additional convection. Moderate to strong instability is forecast to develop this afternoon in a narrow zone along/ahead of the front. While deep-layer shear should remain fairly modest, most 12Z guidance shows a greater concentration of robust convection developing across southern MO and vicinity late this afternoon and early evening. Loosely organized clusters capable of producing mainly damaging winds should spread generally east-southeastward through the evening. Isolated hail may also occur. ...Southern/Central High Plains... No changes have been made to the Slight Risk across the southern/central High Plains. Scattered thunderstorms are expected to develop during the late afternoon and evening in a weak post-frontal, upslope flow regime. Generally upper 50s to low 60s surface dewpoints and steep mid-level lapse rates will support a narrow corridor of moderate instability by late afternoon. While mid-level flow is expected to remain weak, vertically veering wind profiles with height through mid/upper levels will support sufficient deep shear for transient, slow-moving supercells and loosely organized clusters developing off the higher terrain of southern CO and northern NM. Occasional severe gusts appear possible with this activity as low-level lapse rates become steepened through diurnal heating. Some hail may also occur with the strongest cores. ...Michigan... Despite veered low-level winds ahead of the cold front and weak mid-level lapse rates, boundary-layer heating should yield a plume of weak instability, with MLCAPE around 500-1000 J/kg by this afternoon. Strong speed shear will support hodograph elongation. This may yield a supercell or two capable of isolated severe hail and locally strong wind gusts in the eastern U.P. into Lower MI. But, overall coverage of strong/severe thunderstorms is expected to remain rather limited across this area. ..Gleason/Thornton.. 06/29/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Sat Jun 29 2024 Valid 291630Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE OHIO VALLEY/MID-ATLANTIC...OZARKS VICINITY...AND THE SOUTHERN/CENTRAL HIGH PLAINS... ...SUMMARY... Damaging thunderstorm gusts and a few tornadoes appear possible today over parts of the Lower Great Lakes to upper Ohio Valley and Mid-Atlantic. Severe gusts may also be focused this afternoon and evening over the Ozarks vicinity, and the Raton Mesa and adjacent south-central High Plains. ...Lower Great Lakes and Upper Ohio Valley into the Mid-Atlantic... A loosely organized band of convection is ongoing across parts of northern/central OH. As an upper trough over the Great Lakes and eastern Canada continues to move eastward through the period, current expectations are for convection to gradually increase in coverage and intensity this afternoon across eastern OH into western PA. Recent visible satellite imagery shows substantial cloudiness across this area, which should hinder diurnal heating to some extent. Still, even modest heating of the rather moist low-level airmass should support at least weak instability by late this afternoon. Low-level and deep-layer shear appear sufficiently strong for a mix of multicells and supercells. Damaging winds will be a concern with any bowing cluster that can form and spread eastward across parts of the Mid-Atlantic through the afternoon/evening. A couple of tornadoes may also occur with any sustained supercell or embedded QLCS circulations. See Mesoscale Discussion 1472 for more details on the short-term severe threat across OH into northern WV and western PA. There also appears to be some chance for additional convection to develop along the cold front across IL/IN this afternoon, perhaps associated with a remnant MCV over eastern MO. Substantial cloudiness is present across much of this region ahead of the front. But, any thunderstorms that can form may be capable of producing isolated hail and/or strong to damaging winds. Considered including this area in a Slight Risk, but confidence remains low in robust convection persisting with eastward extent into the OH Valley in the wake of earlier thunderstorm activity. ...Ozarks... A Slight Risk for damaging winds has been introduced for southern MO, northeast OK, and vicinity. Outflow from earlier convection, along with the slowly sagging cold front, should continue southward across these areas through late afternoon while also providing a focus for additional convection. Moderate to strong instability is forecast to develop this afternoon in a narrow zone along/ahead of the front. While deep-layer shear should remain fairly modest, most 12Z guidance shows a greater concentration of robust convection developing across southern MO and vicinity late this afternoon and early evening. Loosely organized clusters capable of producing mainly damaging winds should spread generally east-southeastward through the evening. Isolated hail may also occur. ...Southern/Central High Plains... No changes have been made to the Slight Risk across the southern/central High Plains. Scattered thunderstorms are expected to develop during the late afternoon and evening in a weak post-frontal, upslope flow regime. Generally upper 50s to low 60s surface dewpoints and steep mid-level lapse rates will support a narrow corridor of moderate instability by late afternoon. While mid-level flow is expected to remain weak, vertically veering wind profiles with height through mid/upper levels will support sufficient deep shear for transient, slow-moving supercells and loosely organized clusters developing off the higher terrain of southern CO and northern NM. Occasional severe gusts appear possible with this activity as low-level lapse rates become steepened through diurnal heating. Some hail may also occur with the strongest cores. ...Michigan... Despite veered low-level winds ahead of the cold front and weak mid-level lapse rates, boundary-layer heating should yield a plume of weak instability, with MLCAPE around 500-1000 J/kg by this afternoon. Strong speed shear will support hodograph elongation. This may yield a supercell or two capable of isolated severe hail and locally strong wind gusts in the eastern U.P. into Lower MI. But, overall coverage of strong/severe thunderstorms is expected to remain rather limited across this area. ..Gleason/Thornton.. 06/29/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Sat Jun 29 2024 Valid 291630Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE OHIO VALLEY/MID-ATLANTIC...OZARKS VICINITY...AND THE SOUTHERN/CENTRAL HIGH PLAINS... ...SUMMARY... Damaging thunderstorm gusts and a few tornadoes appear possible today over parts of the Lower Great Lakes to upper Ohio Valley and Mid-Atlantic. Severe gusts may also be focused this afternoon and evening over the Ozarks vicinity, and the Raton Mesa and adjacent south-central High Plains. ...Lower Great Lakes and Upper Ohio Valley into the Mid-Atlantic... A loosely organized band of convection is ongoing across parts of northern/central OH. As an upper trough over the Great Lakes and eastern Canada continues to move eastward through the period, current expectations are for convection to gradually increase in coverage and intensity this afternoon across eastern OH into western PA. Recent visible satellite imagery shows substantial cloudiness across this area, which should hinder diurnal heating to some extent. Still, even modest heating of the rather moist low-level airmass should support at least weak instability by late this afternoon. Low-level and deep-layer shear appear sufficiently strong for a mix of multicells and supercells. Damaging winds will be a concern with any bowing cluster that can form and spread eastward across parts of the Mid-Atlantic through the afternoon/evening. A couple of tornadoes may also occur with any sustained supercell or embedded QLCS circulations. See Mesoscale Discussion 1472 for more details on the short-term severe threat across OH into northern WV and western PA. There also appears to be some chance for additional convection to develop along the cold front across IL/IN this afternoon, perhaps associated with a remnant MCV over eastern MO. Substantial cloudiness is present across much of this region ahead of the front. But, any thunderstorms that can form may be capable of producing isolated hail and/or strong to damaging winds. Considered including this area in a Slight Risk, but confidence remains low in robust convection persisting with eastward extent into the OH Valley in the wake of earlier thunderstorm activity. ...Ozarks... A Slight Risk for damaging winds has been introduced for southern MO, northeast OK, and vicinity. Outflow from earlier convection, along with the slowly sagging cold front, should continue southward across these areas through late afternoon while also providing a focus for additional convection. Moderate to strong instability is forecast to develop this afternoon in a narrow zone along/ahead of the front. While deep-layer shear should remain fairly modest, most 12Z guidance shows a greater concentration of robust convection developing across southern MO and vicinity late this afternoon and early evening. Loosely organized clusters capable of producing mainly damaging winds should spread generally east-southeastward through the evening. Isolated hail may also occur. ...Southern/Central High Plains... No changes have been made to the Slight Risk across the southern/central High Plains. Scattered thunderstorms are expected to develop during the late afternoon and evening in a weak post-frontal, upslope flow regime. Generally upper 50s to low 60s surface dewpoints and steep mid-level lapse rates will support a narrow corridor of moderate instability by late afternoon. While mid-level flow is expected to remain weak, vertically veering wind profiles with height through mid/upper levels will support sufficient deep shear for transient, slow-moving supercells and loosely organized clusters developing off the higher terrain of southern CO and northern NM. Occasional severe gusts appear possible with this activity as low-level lapse rates become steepened through diurnal heating. Some hail may also occur with the strongest cores. ...Michigan... Despite veered low-level winds ahead of the cold front and weak mid-level lapse rates, boundary-layer heating should yield a plume of weak instability, with MLCAPE around 500-1000 J/kg by this afternoon. Strong speed shear will support hodograph elongation. This may yield a supercell or two capable of isolated severe hail and locally strong wind gusts in the eastern U.P. into Lower MI. But, overall coverage of strong/severe thunderstorms is expected to remain rather limited across this area. ..Gleason/Thornton.. 06/29/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Sat Jun 29 2024 Valid 291630Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE OHIO VALLEY/MID-ATLANTIC...OZARKS VICINITY...AND THE SOUTHERN/CENTRAL HIGH PLAINS... ...SUMMARY... Damaging thunderstorm gusts and a few tornadoes appear possible today over parts of the Lower Great Lakes to upper Ohio Valley and Mid-Atlantic. Severe gusts may also be focused this afternoon and evening over the Ozarks vicinity, and the Raton Mesa and adjacent south-central High Plains. ...Lower Great Lakes and Upper Ohio Valley into the Mid-Atlantic... A loosely organized band of convection is ongoing across parts of northern/central OH. As an upper trough over the Great Lakes and eastern Canada continues to move eastward through the period, current expectations are for convection to gradually increase in coverage and intensity this afternoon across eastern OH into western PA. Recent visible satellite imagery shows substantial cloudiness across this area, which should hinder diurnal heating to some extent. Still, even modest heating of the rather moist low-level airmass should support at least weak instability by late this afternoon. Low-level and deep-layer shear appear sufficiently strong for a mix of multicells and supercells. Damaging winds will be a concern with any bowing cluster that can form and spread eastward across parts of the Mid-Atlantic through the afternoon/evening. A couple of tornadoes may also occur with any sustained supercell or embedded QLCS circulations. See Mesoscale Discussion 1472 for more details on the short-term severe threat across OH into northern WV and western PA. There also appears to be some chance for additional convection to develop along the cold front across IL/IN this afternoon, perhaps associated with a remnant MCV over eastern MO. Substantial cloudiness is present across much of this region ahead of the front. But, any thunderstorms that can form may be capable of producing isolated hail and/or strong to damaging winds. Considered including this area in a Slight Risk, but confidence remains low in robust convection persisting with eastward extent into the OH Valley in the wake of earlier thunderstorm activity. ...Ozarks... A Slight Risk for damaging winds has been introduced for southern MO, northeast OK, and vicinity. Outflow from earlier convection, along with the slowly sagging cold front, should continue southward across these areas through late afternoon while also providing a focus for additional convection. Moderate to strong instability is forecast to develop this afternoon in a narrow zone along/ahead of the front. While deep-layer shear should remain fairly modest, most 12Z guidance shows a greater concentration of robust convection developing across southern MO and vicinity late this afternoon and early evening. Loosely organized clusters capable of producing mainly damaging winds should spread generally east-southeastward through the evening. Isolated hail may also occur. ...Southern/Central High Plains... No changes have been made to the Slight Risk across the southern/central High Plains. Scattered thunderstorms are expected to develop during the late afternoon and evening in a weak post-frontal, upslope flow regime. Generally upper 50s to low 60s surface dewpoints and steep mid-level lapse rates will support a narrow corridor of moderate instability by late afternoon. While mid-level flow is expected to remain weak, vertically veering wind profiles with height through mid/upper levels will support sufficient deep shear for transient, slow-moving supercells and loosely organized clusters developing off the higher terrain of southern CO and northern NM. Occasional severe gusts appear possible with this activity as low-level lapse rates become steepened through diurnal heating. Some hail may also occur with the strongest cores. ...Michigan... Despite veered low-level winds ahead of the cold front and weak mid-level lapse rates, boundary-layer heating should yield a plume of weak instability, with MLCAPE around 500-1000 J/kg by this afternoon. Strong speed shear will support hodograph elongation. This may yield a supercell or two capable of isolated severe hail and locally strong wind gusts in the eastern U.P. into Lower MI. But, overall coverage of strong/severe thunderstorms is expected to remain rather limited across this area. ..Gleason/Thornton.. 06/29/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Sat Jun 29 2024 Valid 291630Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE OHIO VALLEY/MID-ATLANTIC...OZARKS VICINITY...AND THE SOUTHERN/CENTRAL HIGH PLAINS... ...SUMMARY... Damaging thunderstorm gusts and a few tornadoes appear possible today over parts of the Lower Great Lakes to upper Ohio Valley and Mid-Atlantic. Severe gusts may also be focused this afternoon and evening over the Ozarks vicinity, and the Raton Mesa and adjacent south-central High Plains. ...Lower Great Lakes and Upper Ohio Valley into the Mid-Atlantic... A loosely organized band of convection is ongoing across parts of northern/central OH. As an upper trough over the Great Lakes and eastern Canada continues to move eastward through the period, current expectations are for convection to gradually increase in coverage and intensity this afternoon across eastern OH into western PA. Recent visible satellite imagery shows substantial cloudiness across this area, which should hinder diurnal heating to some extent. Still, even modest heating of the rather moist low-level airmass should support at least weak instability by late this afternoon. Low-level and deep-layer shear appear sufficiently strong for a mix of multicells and supercells. Damaging winds will be a concern with any bowing cluster that can form and spread eastward across parts of the Mid-Atlantic through the afternoon/evening. A couple of tornadoes may also occur with any sustained supercell or embedded QLCS circulations. See Mesoscale Discussion 1472 for more details on the short-term severe threat across OH into northern WV and western PA. There also appears to be some chance for additional convection to develop along the cold front across IL/IN this afternoon, perhaps associated with a remnant MCV over eastern MO. Substantial cloudiness is present across much of this region ahead of the front. But, any thunderstorms that can form may be capable of producing isolated hail and/or strong to damaging winds. Considered including this area in a Slight Risk, but confidence remains low in robust convection persisting with eastward extent into the OH Valley in the wake of earlier thunderstorm activity. ...Ozarks... A Slight Risk for damaging winds has been introduced for southern MO, northeast OK, and vicinity. Outflow from earlier convection, along with the slowly sagging cold front, should continue southward across these areas through late afternoon while also providing a focus for additional convection. Moderate to strong instability is forecast to develop this afternoon in a narrow zone along/ahead of the front. While deep-layer shear should remain fairly modest, most 12Z guidance shows a greater concentration of robust convection developing across southern MO and vicinity late this afternoon and early evening. Loosely organized clusters capable of producing mainly damaging winds should spread generally east-southeastward through the evening. Isolated hail may also occur. ...Southern/Central High Plains... No changes have been made to the Slight Risk across the southern/central High Plains. Scattered thunderstorms are expected to develop during the late afternoon and evening in a weak post-frontal, upslope flow regime. Generally upper 50s to low 60s surface dewpoints and steep mid-level lapse rates will support a narrow corridor of moderate instability by late afternoon. While mid-level flow is expected to remain weak, vertically veering wind profiles with height through mid/upper levels will support sufficient deep shear for transient, slow-moving supercells and loosely organized clusters developing off the higher terrain of southern CO and northern NM. Occasional severe gusts appear possible with this activity as low-level lapse rates become steepened through diurnal heating. Some hail may also occur with the strongest cores. ...Michigan... Despite veered low-level winds ahead of the cold front and weak mid-level lapse rates, boundary-layer heating should yield a plume of weak instability, with MLCAPE around 500-1000 J/kg by this afternoon. Strong speed shear will support hodograph elongation. This may yield a supercell or two capable of isolated severe hail and locally strong wind gusts in the eastern U.P. into Lower MI. But, overall coverage of strong/severe thunderstorms is expected to remain rather limited across this area. ..Gleason/Thornton.. 06/29/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Sat Jun 29 2024 Valid 291630Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE OHIO VALLEY/MID-ATLANTIC...OZARKS VICINITY...AND THE SOUTHERN/CENTRAL HIGH PLAINS... ...SUMMARY... Damaging thunderstorm gusts and a few tornadoes appear possible today over parts of the Lower Great Lakes to upper Ohio Valley and Mid-Atlantic. Severe gusts may also be focused this afternoon and evening over the Ozarks vicinity, and the Raton Mesa and adjacent south-central High Plains. ...Lower Great Lakes and Upper Ohio Valley into the Mid-Atlantic... A loosely organized band of convection is ongoing across parts of northern/central OH. As an upper trough over the Great Lakes and eastern Canada continues to move eastward through the period, current expectations are for convection to gradually increase in coverage and intensity this afternoon across eastern OH into western PA. Recent visible satellite imagery shows substantial cloudiness across this area, which should hinder diurnal heating to some extent. Still, even modest heating of the rather moist low-level airmass should support at least weak instability by late this afternoon. Low-level and deep-layer shear appear sufficiently strong for a mix of multicells and supercells. Damaging winds will be a concern with any bowing cluster that can form and spread eastward across parts of the Mid-Atlantic through the afternoon/evening. A couple of tornadoes may also occur with any sustained supercell or embedded QLCS circulations. See Mesoscale Discussion 1472 for more details on the short-term severe threat across OH into northern WV and western PA. There also appears to be some chance for additional convection to develop along the cold front across IL/IN this afternoon, perhaps associated with a remnant MCV over eastern MO. Substantial cloudiness is present across much of this region ahead of the front. But, any thunderstorms that can form may be capable of producing isolated hail and/or strong to damaging winds. Considered including this area in a Slight Risk, but confidence remains low in robust convection persisting with eastward extent into the OH Valley in the wake of earlier thunderstorm activity. ...Ozarks... A Slight Risk for damaging winds has been introduced for southern MO, northeast OK, and vicinity. Outflow from earlier convection, along with the slowly sagging cold front, should continue southward across these areas through late afternoon while also providing a focus for additional convection. Moderate to strong instability is forecast to develop this afternoon in a narrow zone along/ahead of the front. While deep-layer shear should remain fairly modest, most 12Z guidance shows a greater concentration of robust convection developing across southern MO and vicinity late this afternoon and early evening. Loosely organized clusters capable of producing mainly damaging winds should spread generally east-southeastward through the evening. Isolated hail may also occur. ...Southern/Central High Plains... No changes have been made to the Slight Risk across the southern/central High Plains. Scattered thunderstorms are expected to develop during the late afternoon and evening in a weak post-frontal, upslope flow regime. Generally upper 50s to low 60s surface dewpoints and steep mid-level lapse rates will support a narrow corridor of moderate instability by late afternoon. While mid-level flow is expected to remain weak, vertically veering wind profiles with height through mid/upper levels will support sufficient deep shear for transient, slow-moving supercells and loosely organized clusters developing off the higher terrain of southern CO and northern NM. Occasional severe gusts appear possible with this activity as low-level lapse rates become steepened through diurnal heating. Some hail may also occur with the strongest cores. ...Michigan... Despite veered low-level winds ahead of the cold front and weak mid-level lapse rates, boundary-layer heating should yield a plume of weak instability, with MLCAPE around 500-1000 J/kg by this afternoon. Strong speed shear will support hodograph elongation. This may yield a supercell or two capable of isolated severe hail and locally strong wind gusts in the eastern U.P. into Lower MI. But, overall coverage of strong/severe thunderstorms is expected to remain rather limited across this area. ..Gleason/Thornton.. 06/29/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0749 AM CDT Sat Jun 29 2024 Valid 291300Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE NORTHEAST...AND OVER THE RATON MESA AND NEARBY SOUTH-CENTRAL HIGH PLAINS... ...SUMMARY... Damaging thunderstorm gusts and a few tornadoes are possible today over parts of the Lower Great Lakes to upper Ohio Valley, while severe gusts also may be focused this afternoon and evening over the Raton Mesa and nearby south-central High Plains. ...Synopsis... Broadly, the upper-air pattern will be characterized by a synoptic trough moving ashore from the Pacific and over the West Coast States, the downstream ridge moving slowly out of the northern/ central Rockies onto the adjoining High Plains, and troughing over the Great Lakes and vicinity. Meanwhile, strong subtropical ridging will prevail across the Southeast, southern Plains, and NM. A northern-stream shortwave trough -- evident in moisture-channel imagery over northeastern MN -- will eject east-northeastward today and weaken, while effectively replaced by an upstream perturbation now over portions of ND/MB. The resulting shortwave trough should proceed eastward across the Upper Great Lakes to Lake Huron and adjoining parts of ON by 12Z tomorrow. To its south and southeast, a belt of strong, cyclonically curved flow will cover the mid/upper Ohio Valley and Northeast, with minor embedded perturbations (some convectively generated upstream from prior/overnight activity). At the surface, the 11Z analysis showed a low over central Lake Superior, with cold front across central Upper MI, southern WI, southern IA, central KS, and north-central NM. By 00Z, the cold front should move to northern IN, central IL, southern MO, northern OK, the northern TX Panhandle, and northeastern/central NM. By 12Z, the front should extend from western parts of NY/PA across KY, the MO Bootheel area, and northern AR, becoming quasistationary over central/western OK, the central TX Panhandle, and east-central NM. A prefrontal surface trough should shift eastward from the St. Lawrence Valley/Lower Great Lakes across the northern Appalachians and northern Mid-Atlantic States through the period. ...Northeast/Ohio Valley/Great Lakes... Scattered thunderstorms are expected to form episodically from midday through afternoon -- predominantly ahead of the surface cold front. Frontal convection over parts of Lower MI also is possible this afternoon, with isolated severe hail/gusts. The main severe threat, however should be over parts of the Lower Great Lakes/upper Ohio Valley into nearly Appalachians. With weak capping, activity may form on a variety of foci, near the main surface trough, outflow boundaries from morning clouds/precip, and over areas of differential heating and orographic lift. Activity should organize into one or more lines with embedded supercells and bowing/LEWP segments possible. The main threat will be damaging to severe gusts in and near the 15%/"slight" area, though any supercells or embedded QLCS vortices also will pose a tornado threat. Despite weak mid/upper-level lapse rates over most of this region, warm-sector moisture will be characterized by mid 60s to lower 70s F surface dewpoints. This will combine with pockets of sustained surface heating to yield MLCAPE in the 1000-2000 J/kg range. Veering and strengthening of winds with height in low levels should yield enlarged hodographs below 3 km, with effective SRH in the 150-250 J/kg range overlapping areas of favorable heating in some parts of the upper Ohio Valley area into central PA. Little speed shear is apparent from the top of the boundary layer into the mid/upper levels, however, limiting deep shear, and storm structure may become messy rather quickly. Overall, convection should weaken as it approaches the Atlantic Coast this evening, and the foregoing inflow layer becomes more stable. ...South-central Rockies/High Plains... Isolated to scattered thunderstorms are forecast to develop this afternoon over higher terrain from the southern Front Range area across the Sangre de Cristos and Raton Mesa. This will occur as strong heating of higher terrain preferentially erodes MLCINH, in the presence of post-frontal upslope flow in low levels, and related moisture advection to at least partially offset moisture loss due to mixing. The easterly component also should aid storm-relative boundary-layer flow and deep shear for activity propagating eastward off the elevated terrain, with a mix of multicells and transient supercells possible. Despite modest low/middle-level wind speeds, forecast soundings reasonably depict enough veering with height to yield 35-45-kt effective-shear magnitudes, amidst 500-1500 J/kg MLCAPE and steep boundary-layer lapse rates. Some of the resulting convection may coalesce into a complex of thunderstorms with a cold pool, in turn driving eastward-directed forward propagation near the post-frontal moist axis and across parts of southeastern CO, northeastern NM, the adjacent Panhandles, and or southwestern KS, with a relatively focused threat of severe gusts. ...Ozarks/south-central Plains... Ongoing, isolated to widely scattered convection over parts of KS/MO should weaken/dissipate through the remainder of the morning, but may leave behind enough cloud material and (especially in MO) outflow to augment frontal baroclinicity for afternoon convective initiation. Widely scattered to scattered thunderstorms should develop on and near the front this afternoon from northern OK and extreme southern KS to the Ozarks, in a regime of MLCINH substantially removed by modest low-level convergence and strong diurnal/prefrontal heating. Deep mixing south of the front should reduce surface dewpoints and buoyancy in the warm sector, but adequate moisture (with 60s to low 70s F surface dewpoints) should linger in a narrow post-frontal corridor supporting 2000-3000 J/kg MLCAPE. The net result should be high-based, multicell thunderstorms in mostly weak deep shear, with pulse severe in the form of gusts and hail. A conditional risk exists for locally significant (65+ kt) gusts, given the favorably deep subcloud mixed layer with large DCAPE. However, mesoscale foci for denser coverage of such a threat still appear too nebulous for a 15% unconditional gust outlook within the broader marginal area. ..Edwards/Kerr.. 06/29/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0749 AM CDT Sat Jun 29 2024 Valid 291300Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE NORTHEAST...AND OVER THE RATON MESA AND NEARBY SOUTH-CENTRAL HIGH PLAINS... ...SUMMARY... Damaging thunderstorm gusts and a few tornadoes are possible today over parts of the Lower Great Lakes to upper Ohio Valley, while severe gusts also may be focused this afternoon and evening over the Raton Mesa and nearby south-central High Plains. ...Synopsis... Broadly, the upper-air pattern will be characterized by a synoptic trough moving ashore from the Pacific and over the West Coast States, the downstream ridge moving slowly out of the northern/ central Rockies onto the adjoining High Plains, and troughing over the Great Lakes and vicinity. Meanwhile, strong subtropical ridging will prevail across the Southeast, southern Plains, and NM. A northern-stream shortwave trough -- evident in moisture-channel imagery over northeastern MN -- will eject east-northeastward today and weaken, while effectively replaced by an upstream perturbation now over portions of ND/MB. The resulting shortwave trough should proceed eastward across the Upper Great Lakes to Lake Huron and adjoining parts of ON by 12Z tomorrow. To its south and southeast, a belt of strong, cyclonically curved flow will cover the mid/upper Ohio Valley and Northeast, with minor embedded perturbations (some convectively generated upstream from prior/overnight activity). At the surface, the 11Z analysis showed a low over central Lake Superior, with cold front across central Upper MI, southern WI, southern IA, central KS, and north-central NM. By 00Z, the cold front should move to northern IN, central IL, southern MO, northern OK, the northern TX Panhandle, and northeastern/central NM. By 12Z, the front should extend from western parts of NY/PA across KY, the MO Bootheel area, and northern AR, becoming quasistationary over central/western OK, the central TX Panhandle, and east-central NM. A prefrontal surface trough should shift eastward from the St. Lawrence Valley/Lower Great Lakes across the northern Appalachians and northern Mid-Atlantic States through the period. ...Northeast/Ohio Valley/Great Lakes... Scattered thunderstorms are expected to form episodically from midday through afternoon -- predominantly ahead of the surface cold front. Frontal convection over parts of Lower MI also is possible this afternoon, with isolated severe hail/gusts. The main severe threat, however should be over parts of the Lower Great Lakes/upper Ohio Valley into nearly Appalachians. With weak capping, activity may form on a variety of foci, near the main surface trough, outflow boundaries from morning clouds/precip, and over areas of differential heating and orographic lift. Activity should organize into one or more lines with embedded supercells and bowing/LEWP segments possible. The main threat will be damaging to severe gusts in and near the 15%/"slight" area, though any supercells or embedded QLCS vortices also will pose a tornado threat. Despite weak mid/upper-level lapse rates over most of this region, warm-sector moisture will be characterized by mid 60s to lower 70s F surface dewpoints. This will combine with pockets of sustained surface heating to yield MLCAPE in the 1000-2000 J/kg range. Veering and strengthening of winds with height in low levels should yield enlarged hodographs below 3 km, with effective SRH in the 150-250 J/kg range overlapping areas of favorable heating in some parts of the upper Ohio Valley area into central PA. Little speed shear is apparent from the top of the boundary layer into the mid/upper levels, however, limiting deep shear, and storm structure may become messy rather quickly. Overall, convection should weaken as it approaches the Atlantic Coast this evening, and the foregoing inflow layer becomes more stable. ...South-central Rockies/High Plains... Isolated to scattered thunderstorms are forecast to develop this afternoon over higher terrain from the southern Front Range area across the Sangre de Cristos and Raton Mesa. This will occur as strong heating of higher terrain preferentially erodes MLCINH, in the presence of post-frontal upslope flow in low levels, and related moisture advection to at least partially offset moisture loss due to mixing. The easterly component also should aid storm-relative boundary-layer flow and deep shear for activity propagating eastward off the elevated terrain, with a mix of multicells and transient supercells possible. Despite modest low/middle-level wind speeds, forecast soundings reasonably depict enough veering with height to yield 35-45-kt effective-shear magnitudes, amidst 500-1500 J/kg MLCAPE and steep boundary-layer lapse rates. Some of the resulting convection may coalesce into a complex of thunderstorms with a cold pool, in turn driving eastward-directed forward propagation near the post-frontal moist axis and across parts of southeastern CO, northeastern NM, the adjacent Panhandles, and or southwestern KS, with a relatively focused threat of severe gusts. ...Ozarks/south-central Plains... Ongoing, isolated to widely scattered convection over parts of KS/MO should weaken/dissipate through the remainder of the morning, but may leave behind enough cloud material and (especially in MO) outflow to augment frontal baroclinicity for afternoon convective initiation. Widely scattered to scattered thunderstorms should develop on and near the front this afternoon from northern OK and extreme southern KS to the Ozarks, in a regime of MLCINH substantially removed by modest low-level convergence and strong diurnal/prefrontal heating. Deep mixing south of the front should reduce surface dewpoints and buoyancy in the warm sector, but adequate moisture (with 60s to low 70s F surface dewpoints) should linger in a narrow post-frontal corridor supporting 2000-3000 J/kg MLCAPE. The net result should be high-based, multicell thunderstorms in mostly weak deep shear, with pulse severe in the form of gusts and hail. A conditional risk exists for locally significant (65+ kt) gusts, given the favorably deep subcloud mixed layer with large DCAPE. However, mesoscale foci for denser coverage of such a threat still appear too nebulous for a 15% unconditional gust outlook within the broader marginal area. ..Edwards/Kerr.. 06/29/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0749 AM CDT Sat Jun 29 2024 Valid 291300Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE NORTHEAST...AND OVER THE RATON MESA AND NEARBY SOUTH-CENTRAL HIGH PLAINS... ...SUMMARY... Damaging thunderstorm gusts and a few tornadoes are possible today over parts of the Lower Great Lakes to upper Ohio Valley, while severe gusts also may be focused this afternoon and evening over the Raton Mesa and nearby south-central High Plains. ...Synopsis... Broadly, the upper-air pattern will be characterized by a synoptic trough moving ashore from the Pacific and over the West Coast States, the downstream ridge moving slowly out of the northern/ central Rockies onto the adjoining High Plains, and troughing over the Great Lakes and vicinity. Meanwhile, strong subtropical ridging will prevail across the Southeast, southern Plains, and NM. A northern-stream shortwave trough -- evident in moisture-channel imagery over northeastern MN -- will eject east-northeastward today and weaken, while effectively replaced by an upstream perturbation now over portions of ND/MB. The resulting shortwave trough should proceed eastward across the Upper Great Lakes to Lake Huron and adjoining parts of ON by 12Z tomorrow. To its south and southeast, a belt of strong, cyclonically curved flow will cover the mid/upper Ohio Valley and Northeast, with minor embedded perturbations (some convectively generated upstream from prior/overnight activity). At the surface, the 11Z analysis showed a low over central Lake Superior, with cold front across central Upper MI, southern WI, southern IA, central KS, and north-central NM. By 00Z, the cold front should move to northern IN, central IL, southern MO, northern OK, the northern TX Panhandle, and northeastern/central NM. By 12Z, the front should extend from western parts of NY/PA across KY, the MO Bootheel area, and northern AR, becoming quasistationary over central/western OK, the central TX Panhandle, and east-central NM. A prefrontal surface trough should shift eastward from the St. Lawrence Valley/Lower Great Lakes across the northern Appalachians and northern Mid-Atlantic States through the period. ...Northeast/Ohio Valley/Great Lakes... Scattered thunderstorms are expected to form episodically from midday through afternoon -- predominantly ahead of the surface cold front. Frontal convection over parts of Lower MI also is possible this afternoon, with isolated severe hail/gusts. The main severe threat, however should be over parts of the Lower Great Lakes/upper Ohio Valley into nearly Appalachians. With weak capping, activity may form on a variety of foci, near the main surface trough, outflow boundaries from morning clouds/precip, and over areas of differential heating and orographic lift. Activity should organize into one or more lines with embedded supercells and bowing/LEWP segments possible. The main threat will be damaging to severe gusts in and near the 15%/"slight" area, though any supercells or embedded QLCS vortices also will pose a tornado threat. Despite weak mid/upper-level lapse rates over most of this region, warm-sector moisture will be characterized by mid 60s to lower 70s F surface dewpoints. This will combine with pockets of sustained surface heating to yield MLCAPE in the 1000-2000 J/kg range. Veering and strengthening of winds with height in low levels should yield enlarged hodographs below 3 km, with effective SRH in the 150-250 J/kg range overlapping areas of favorable heating in some parts of the upper Ohio Valley area into central PA. Little speed shear is apparent from the top of the boundary layer into the mid/upper levels, however, limiting deep shear, and storm structure may become messy rather quickly. Overall, convection should weaken as it approaches the Atlantic Coast this evening, and the foregoing inflow layer becomes more stable. ...South-central Rockies/High Plains... Isolated to scattered thunderstorms are forecast to develop this afternoon over higher terrain from the southern Front Range area across the Sangre de Cristos and Raton Mesa. This will occur as strong heating of higher terrain preferentially erodes MLCINH, in the presence of post-frontal upslope flow in low levels, and related moisture advection to at least partially offset moisture loss due to mixing. The easterly component also should aid storm-relative boundary-layer flow and deep shear for activity propagating eastward off the elevated terrain, with a mix of multicells and transient supercells possible. Despite modest low/middle-level wind speeds, forecast soundings reasonably depict enough veering with height to yield 35-45-kt effective-shear magnitudes, amidst 500-1500 J/kg MLCAPE and steep boundary-layer lapse rates. Some of the resulting convection may coalesce into a complex of thunderstorms with a cold pool, in turn driving eastward-directed forward propagation near the post-frontal moist axis and across parts of southeastern CO, northeastern NM, the adjacent Panhandles, and or southwestern KS, with a relatively focused threat of severe gusts. ...Ozarks/south-central Plains... Ongoing, isolated to widely scattered convection over parts of KS/MO should weaken/dissipate through the remainder of the morning, but may leave behind enough cloud material and (especially in MO) outflow to augment frontal baroclinicity for afternoon convective initiation. Widely scattered to scattered thunderstorms should develop on and near the front this afternoon from northern OK and extreme southern KS to the Ozarks, in a regime of MLCINH substantially removed by modest low-level convergence and strong diurnal/prefrontal heating. Deep mixing south of the front should reduce surface dewpoints and buoyancy in the warm sector, but adequate moisture (with 60s to low 70s F surface dewpoints) should linger in a narrow post-frontal corridor supporting 2000-3000 J/kg MLCAPE. The net result should be high-based, multicell thunderstorms in mostly weak deep shear, with pulse severe in the form of gusts and hail. A conditional risk exists for locally significant (65+ kt) gusts, given the favorably deep subcloud mixed layer with large DCAPE. However, mesoscale foci for denser coverage of such a threat still appear too nebulous for a 15% unconditional gust outlook within the broader marginal area. ..Edwards/Kerr.. 06/29/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0749 AM CDT Sat Jun 29 2024 Valid 291300Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE NORTHEAST...AND OVER THE RATON MESA AND NEARBY SOUTH-CENTRAL HIGH PLAINS... ...SUMMARY... Damaging thunderstorm gusts and a few tornadoes are possible today over parts of the Lower Great Lakes to upper Ohio Valley, while severe gusts also may be focused this afternoon and evening over the Raton Mesa and nearby south-central High Plains. ...Synopsis... Broadly, the upper-air pattern will be characterized by a synoptic trough moving ashore from the Pacific and over the West Coast States, the downstream ridge moving slowly out of the northern/ central Rockies onto the adjoining High Plains, and troughing over the Great Lakes and vicinity. Meanwhile, strong subtropical ridging will prevail across the Southeast, southern Plains, and NM. A northern-stream shortwave trough -- evident in moisture-channel imagery over northeastern MN -- will eject east-northeastward today and weaken, while effectively replaced by an upstream perturbation now over portions of ND/MB. The resulting shortwave trough should proceed eastward across the Upper Great Lakes to Lake Huron and adjoining parts of ON by 12Z tomorrow. To its south and southeast, a belt of strong, cyclonically curved flow will cover the mid/upper Ohio Valley and Northeast, with minor embedded perturbations (some convectively generated upstream from prior/overnight activity). At the surface, the 11Z analysis showed a low over central Lake Superior, with cold front across central Upper MI, southern WI, southern IA, central KS, and north-central NM. By 00Z, the cold front should move to northern IN, central IL, southern MO, northern OK, the northern TX Panhandle, and northeastern/central NM. By 12Z, the front should extend from western parts of NY/PA across KY, the MO Bootheel area, and northern AR, becoming quasistationary over central/western OK, the central TX Panhandle, and east-central NM. A prefrontal surface trough should shift eastward from the St. Lawrence Valley/Lower Great Lakes across the northern Appalachians and northern Mid-Atlantic States through the period. ...Northeast/Ohio Valley/Great Lakes... Scattered thunderstorms are expected to form episodically from midday through afternoon -- predominantly ahead of the surface cold front. Frontal convection over parts of Lower MI also is possible this afternoon, with isolated severe hail/gusts. The main severe threat, however should be over parts of the Lower Great Lakes/upper Ohio Valley into nearly Appalachians. With weak capping, activity may form on a variety of foci, near the main surface trough, outflow boundaries from morning clouds/precip, and over areas of differential heating and orographic lift. Activity should organize into one or more lines with embedded supercells and bowing/LEWP segments possible. The main threat will be damaging to severe gusts in and near the 15%/"slight" area, though any supercells or embedded QLCS vortices also will pose a tornado threat. Despite weak mid/upper-level lapse rates over most of this region, warm-sector moisture will be characterized by mid 60s to lower 70s F surface dewpoints. This will combine with pockets of sustained surface heating to yield MLCAPE in the 1000-2000 J/kg range. Veering and strengthening of winds with height in low levels should yield enlarged hodographs below 3 km, with effective SRH in the 150-250 J/kg range overlapping areas of favorable heating in some parts of the upper Ohio Valley area into central PA. Little speed shear is apparent from the top of the boundary layer into the mid/upper levels, however, limiting deep shear, and storm structure may become messy rather quickly. Overall, convection should weaken as it approaches the Atlantic Coast this evening, and the foregoing inflow layer becomes more stable. ...South-central Rockies/High Plains... Isolated to scattered thunderstorms are forecast to develop this afternoon over higher terrain from the southern Front Range area across the Sangre de Cristos and Raton Mesa. This will occur as strong heating of higher terrain preferentially erodes MLCINH, in the presence of post-frontal upslope flow in low levels, and related moisture advection to at least partially offset moisture loss due to mixing. The easterly component also should aid storm-relative boundary-layer flow and deep shear for activity propagating eastward off the elevated terrain, with a mix of multicells and transient supercells possible. Despite modest low/middle-level wind speeds, forecast soundings reasonably depict enough veering with height to yield 35-45-kt effective-shear magnitudes, amidst 500-1500 J/kg MLCAPE and steep boundary-layer lapse rates. Some of the resulting convection may coalesce into a complex of thunderstorms with a cold pool, in turn driving eastward-directed forward propagation near the post-frontal moist axis and across parts of southeastern CO, northeastern NM, the adjacent Panhandles, and or southwestern KS, with a relatively focused threat of severe gusts. ...Ozarks/south-central Plains... Ongoing, isolated to widely scattered convection over parts of KS/MO should weaken/dissipate through the remainder of the morning, but may leave behind enough cloud material and (especially in MO) outflow to augment frontal baroclinicity for afternoon convective initiation. Widely scattered to scattered thunderstorms should develop on and near the front this afternoon from northern OK and extreme southern KS to the Ozarks, in a regime of MLCINH substantially removed by modest low-level convergence and strong diurnal/prefrontal heating. Deep mixing south of the front should reduce surface dewpoints and buoyancy in the warm sector, but adequate moisture (with 60s to low 70s F surface dewpoints) should linger in a narrow post-frontal corridor supporting 2000-3000 J/kg MLCAPE. The net result should be high-based, multicell thunderstorms in mostly weak deep shear, with pulse severe in the form of gusts and hail. A conditional risk exists for locally significant (65+ kt) gusts, given the favorably deep subcloud mixed layer with large DCAPE. However, mesoscale foci for denser coverage of such a threat still appear too nebulous for a 15% unconditional gust outlook within the broader marginal area. ..Edwards/Kerr.. 06/29/2024 Read more