Severe Storms

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0134 PM CDT Fri Jun 28 2024 Valid 291200Z - 301200Z The Elevated area was expanded north and east across eastern Nevada and western Utah, as a broader area of south-southwest sustained winds of 15-25 mph and minimum RH of 5-15% is expected. While thunderstorms produced wetting rains in parts of the outlook area this week, holdovers remain possible given the forecast winds and RH. Isolated mixed wet and dry thunderstorms are possible from northeast Oregon into north Idaho tomorrow evening and overnight, but the low probabilities/high uncertainty for thunderstorms and underlying fuel conditions preclude introducing an Iso DryT area. ..Nauslar.. 06/28/2024 .PREV DISCUSSION... /ISSUED 0126 AM CDT Fri Jun 28 2024/ ...Synopsis... Upper ridging will build across the central Rockies into the Mississippi Valley tomorrow/Saturday as a mid-level trough impinges on the Interior West. A modest surface cyclone will develop over the Great Basin by afternoon, encouraging dry and windy conditions across portions of southern Nevada and surrounding areas. 15+ mph sustained southwesterly surface winds will overlap with 5-10 percent RH by afternoon peak heating over southern parts of the Great Basin. Some guidance suggests that wind speeds well over 20 mph may be observed over southern Nevada. However, marginally receptive fuels suggest that only Elevated highlights are warranted at this time. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0134 PM CDT Fri Jun 28 2024 Valid 291200Z - 301200Z The Elevated area was expanded north and east across eastern Nevada and western Utah, as a broader area of south-southwest sustained winds of 15-25 mph and minimum RH of 5-15% is expected. While thunderstorms produced wetting rains in parts of the outlook area this week, holdovers remain possible given the forecast winds and RH. Isolated mixed wet and dry thunderstorms are possible from northeast Oregon into north Idaho tomorrow evening and overnight, but the low probabilities/high uncertainty for thunderstorms and underlying fuel conditions preclude introducing an Iso DryT area. ..Nauslar.. 06/28/2024 .PREV DISCUSSION... /ISSUED 0126 AM CDT Fri Jun 28 2024/ ...Synopsis... Upper ridging will build across the central Rockies into the Mississippi Valley tomorrow/Saturday as a mid-level trough impinges on the Interior West. A modest surface cyclone will develop over the Great Basin by afternoon, encouraging dry and windy conditions across portions of southern Nevada and surrounding areas. 15+ mph sustained southwesterly surface winds will overlap with 5-10 percent RH by afternoon peak heating over southern parts of the Great Basin. Some guidance suggests that wind speeds well over 20 mph may be observed over southern Nevada. However, marginally receptive fuels suggest that only Elevated highlights are warranted at this time. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0134 PM CDT Fri Jun 28 2024 Valid 291200Z - 301200Z The Elevated area was expanded north and east across eastern Nevada and western Utah, as a broader area of south-southwest sustained winds of 15-25 mph and minimum RH of 5-15% is expected. While thunderstorms produced wetting rains in parts of the outlook area this week, holdovers remain possible given the forecast winds and RH. Isolated mixed wet and dry thunderstorms are possible from northeast Oregon into north Idaho tomorrow evening and overnight, but the low probabilities/high uncertainty for thunderstorms and underlying fuel conditions preclude introducing an Iso DryT area. ..Nauslar.. 06/28/2024 .PREV DISCUSSION... /ISSUED 0126 AM CDT Fri Jun 28 2024/ ...Synopsis... Upper ridging will build across the central Rockies into the Mississippi Valley tomorrow/Saturday as a mid-level trough impinges on the Interior West. A modest surface cyclone will develop over the Great Basin by afternoon, encouraging dry and windy conditions across portions of southern Nevada and surrounding areas. 15+ mph sustained southwesterly surface winds will overlap with 5-10 percent RH by afternoon peak heating over southern parts of the Great Basin. Some guidance suggests that wind speeds well over 20 mph may be observed over southern Nevada. However, marginally receptive fuels suggest that only Elevated highlights are warranted at this time. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0134 PM CDT Fri Jun 28 2024 Valid 291200Z - 301200Z The Elevated area was expanded north and east across eastern Nevada and western Utah, as a broader area of south-southwest sustained winds of 15-25 mph and minimum RH of 5-15% is expected. While thunderstorms produced wetting rains in parts of the outlook area this week, holdovers remain possible given the forecast winds and RH. Isolated mixed wet and dry thunderstorms are possible from northeast Oregon into north Idaho tomorrow evening and overnight, but the low probabilities/high uncertainty for thunderstorms and underlying fuel conditions preclude introducing an Iso DryT area. ..Nauslar.. 06/28/2024 .PREV DISCUSSION... /ISSUED 0126 AM CDT Fri Jun 28 2024/ ...Synopsis... Upper ridging will build across the central Rockies into the Mississippi Valley tomorrow/Saturday as a mid-level trough impinges on the Interior West. A modest surface cyclone will develop over the Great Basin by afternoon, encouraging dry and windy conditions across portions of southern Nevada and surrounding areas. 15+ mph sustained southwesterly surface winds will overlap with 5-10 percent RH by afternoon peak heating over southern parts of the Great Basin. Some guidance suggests that wind speeds well over 20 mph may be observed over southern Nevada. However, marginally receptive fuels suggest that only Elevated highlights are warranted at this time. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0134 PM CDT Fri Jun 28 2024 Valid 291200Z - 301200Z The Elevated area was expanded north and east across eastern Nevada and western Utah, as a broader area of south-southwest sustained winds of 15-25 mph and minimum RH of 5-15% is expected. While thunderstorms produced wetting rains in parts of the outlook area this week, holdovers remain possible given the forecast winds and RH. Isolated mixed wet and dry thunderstorms are possible from northeast Oregon into north Idaho tomorrow evening and overnight, but the low probabilities/high uncertainty for thunderstorms and underlying fuel conditions preclude introducing an Iso DryT area. ..Nauslar.. 06/28/2024 .PREV DISCUSSION... /ISSUED 0126 AM CDT Fri Jun 28 2024/ ...Synopsis... Upper ridging will build across the central Rockies into the Mississippi Valley tomorrow/Saturday as a mid-level trough impinges on the Interior West. A modest surface cyclone will develop over the Great Basin by afternoon, encouraging dry and windy conditions across portions of southern Nevada and surrounding areas. 15+ mph sustained southwesterly surface winds will overlap with 5-10 percent RH by afternoon peak heating over southern parts of the Great Basin. Some guidance suggests that wind speeds well over 20 mph may be observed over southern Nevada. However, marginally receptive fuels suggest that only Elevated highlights are warranted at this time. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0134 PM CDT Fri Jun 28 2024 Valid 291200Z - 301200Z The Elevated area was expanded north and east across eastern Nevada and western Utah, as a broader area of south-southwest sustained winds of 15-25 mph and minimum RH of 5-15% is expected. While thunderstorms produced wetting rains in parts of the outlook area this week, holdovers remain possible given the forecast winds and RH. Isolated mixed wet and dry thunderstorms are possible from northeast Oregon into north Idaho tomorrow evening and overnight, but the low probabilities/high uncertainty for thunderstorms and underlying fuel conditions preclude introducing an Iso DryT area. ..Nauslar.. 06/28/2024 .PREV DISCUSSION... /ISSUED 0126 AM CDT Fri Jun 28 2024/ ...Synopsis... Upper ridging will build across the central Rockies into the Mississippi Valley tomorrow/Saturday as a mid-level trough impinges on the Interior West. A modest surface cyclone will develop over the Great Basin by afternoon, encouraging dry and windy conditions across portions of southern Nevada and surrounding areas. 15+ mph sustained southwesterly surface winds will overlap with 5-10 percent RH by afternoon peak heating over southern parts of the Great Basin. Some guidance suggests that wind speeds well over 20 mph may be observed over southern Nevada. However, marginally receptive fuels suggest that only Elevated highlights are warranted at this time. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1222 PM CDT Fri Jun 28 2024 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM OHIO INTO PORTIONS WEST VIRGINIA...MARYLAND...PENNSYLVANIA AND NEW YORK... ...SUMMARY... Scattered damaging winds and a couple tornadoes are possible on Saturday from parts of Ohio into northern West Virginia/Maryland, central and western Pennsylvania, and western New York. ...Ohio Valley to the Northeast... Several vorticity maxima are forecast to migrate across the region within an area of enhanced southwesterly flow aloft ahead of the main upper shortwave trough progressing from the Upper Midwest to the lower Great Lakes. At the surface, low pressure will spread east/northeast from the upper Great Lakes into Ontario/Quebec. As this occurs, strong theta-e advection on southwesterly low-level flow will result in a very moist airmass spreading north/northeast from the Midwest into much of the Northeast. Early cloudiness and periods of showers may limit diurnal destabilization from eastern PA into NY. Pockets of stronger instability will overlap 30-40 kt westerly midlevel flow from parts of Ohio into western/central PA/NY. While midlevel lapse rates will remain quite poor, sufficient effective shear magnitudes amid rich boundary-layer moisture should support organized clusters and line segments capable of strong/damaging gusts. Vertically veering low-level winds will support somewhat enlarged and curved hodographs, with sufficient low-level instability and 0-1 km SRH. In addition to damaging gusts, a couple of tornadoes also will be possible. A more conditional risk may exist from late evening into the early overnight hours across parts of northern NY into VT as the surface front impinges on the area and the main upper shortwave trough ejects eastward. Strong vertical shear will be in place amid a very moist airmass. However, convection may remain elevated given poor timing with the diurnal cycle and impacts from daytime convection. If convection can become surface-based, damaging gusts will be possible. ...OK/KS to the Mid-MS Valley... Convection may be ongoing Saturday morning across parts of central MO. This activity may weaken during the morning, or slowly reintensify during the afternoon along outflow or the southward-advancing surface cold front. Additional convection is expected to develop along the sagging front across southern KS/northern OK during the late afternoon/evening. A couple of forward-propagating clusters are possible within this area of modest vertical shear, but rich boundary-layer moisture (dewpoints in the upper 60s/low 70s F) and moderate to strong instability. Isolated severe/damaging gusts and a few instances of hail will be possible with this activity. A corridor of higher probabilities may be needed in subsequent outlooks if confidence increases in location of better organized frontal convection. ...Central/Southern High Plains... Isolated convection is expected during the evening in a post-frontal upslope flow regime. Near 60 F surface dewpoints and steep midlevel lapse rates will support a corridor of moderate instability. While deep-layer flow will be light, vertically veering wind profiles will support 30-40 kt effective shear magnitudes amid a deeply mixed boundary-layer. Isolated strong to severe thunderstorms capable of strong gusts and hail will be possible. ...Northern IL into eastern WI and MI... Most forecast guidance is fairly sparse with convection across this area on Saturday. However, a very moist and unstable airmass will be in place ahead of the east/southeast-advancing cold front, along with favorable vertical shear for organized storms. Large-scale ascent will remain somewhat weak and ill-timed with the cold front progression, and low-level frontal convergence also will be poor. Severe probabilities have been adjusted some over the region based on low storm coverage and latest trends. However, a conditional severe threat will exist if storms develop. ..Leitman.. 06/28/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1222 PM CDT Fri Jun 28 2024 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM OHIO INTO PORTIONS WEST VIRGINIA...MARYLAND...PENNSYLVANIA AND NEW YORK... ...SUMMARY... Scattered damaging winds and a couple tornadoes are possible on Saturday from parts of Ohio into northern West Virginia/Maryland, central and western Pennsylvania, and western New York. ...Ohio Valley to the Northeast... Several vorticity maxima are forecast to migrate across the region within an area of enhanced southwesterly flow aloft ahead of the main upper shortwave trough progressing from the Upper Midwest to the lower Great Lakes. At the surface, low pressure will spread east/northeast from the upper Great Lakes into Ontario/Quebec. As this occurs, strong theta-e advection on southwesterly low-level flow will result in a very moist airmass spreading north/northeast from the Midwest into much of the Northeast. Early cloudiness and periods of showers may limit diurnal destabilization from eastern PA into NY. Pockets of stronger instability will overlap 30-40 kt westerly midlevel flow from parts of Ohio into western/central PA/NY. While midlevel lapse rates will remain quite poor, sufficient effective shear magnitudes amid rich boundary-layer moisture should support organized clusters and line segments capable of strong/damaging gusts. Vertically veering low-level winds will support somewhat enlarged and curved hodographs, with sufficient low-level instability and 0-1 km SRH. In addition to damaging gusts, a couple of tornadoes also will be possible. A more conditional risk may exist from late evening into the early overnight hours across parts of northern NY into VT as the surface front impinges on the area and the main upper shortwave trough ejects eastward. Strong vertical shear will be in place amid a very moist airmass. However, convection may remain elevated given poor timing with the diurnal cycle and impacts from daytime convection. If convection can become surface-based, damaging gusts will be possible. ...OK/KS to the Mid-MS Valley... Convection may be ongoing Saturday morning across parts of central MO. This activity may weaken during the morning, or slowly reintensify during the afternoon along outflow or the southward-advancing surface cold front. Additional convection is expected to develop along the sagging front across southern KS/northern OK during the late afternoon/evening. A couple of forward-propagating clusters are possible within this area of modest vertical shear, but rich boundary-layer moisture (dewpoints in the upper 60s/low 70s F) and moderate to strong instability. Isolated severe/damaging gusts and a few instances of hail will be possible with this activity. A corridor of higher probabilities may be needed in subsequent outlooks if confidence increases in location of better organized frontal convection. ...Central/Southern High Plains... Isolated convection is expected during the evening in a post-frontal upslope flow regime. Near 60 F surface dewpoints and steep midlevel lapse rates will support a corridor of moderate instability. While deep-layer flow will be light, vertically veering wind profiles will support 30-40 kt effective shear magnitudes amid a deeply mixed boundary-layer. Isolated strong to severe thunderstorms capable of strong gusts and hail will be possible. ...Northern IL into eastern WI and MI... Most forecast guidance is fairly sparse with convection across this area on Saturday. However, a very moist and unstable airmass will be in place ahead of the east/southeast-advancing cold front, along with favorable vertical shear for organized storms. Large-scale ascent will remain somewhat weak and ill-timed with the cold front progression, and low-level frontal convergence also will be poor. Severe probabilities have been adjusted some over the region based on low storm coverage and latest trends. However, a conditional severe threat will exist if storms develop. ..Leitman.. 06/28/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1222 PM CDT Fri Jun 28 2024 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM OHIO INTO PORTIONS WEST VIRGINIA...MARYLAND...PENNSYLVANIA AND NEW YORK... ...SUMMARY... Scattered damaging winds and a couple tornadoes are possible on Saturday from parts of Ohio into northern West Virginia/Maryland, central and western Pennsylvania, and western New York. ...Ohio Valley to the Northeast... Several vorticity maxima are forecast to migrate across the region within an area of enhanced southwesterly flow aloft ahead of the main upper shortwave trough progressing from the Upper Midwest to the lower Great Lakes. At the surface, low pressure will spread east/northeast from the upper Great Lakes into Ontario/Quebec. As this occurs, strong theta-e advection on southwesterly low-level flow will result in a very moist airmass spreading north/northeast from the Midwest into much of the Northeast. Early cloudiness and periods of showers may limit diurnal destabilization from eastern PA into NY. Pockets of stronger instability will overlap 30-40 kt westerly midlevel flow from parts of Ohio into western/central PA/NY. While midlevel lapse rates will remain quite poor, sufficient effective shear magnitudes amid rich boundary-layer moisture should support organized clusters and line segments capable of strong/damaging gusts. Vertically veering low-level winds will support somewhat enlarged and curved hodographs, with sufficient low-level instability and 0-1 km SRH. In addition to damaging gusts, a couple of tornadoes also will be possible. A more conditional risk may exist from late evening into the early overnight hours across parts of northern NY into VT as the surface front impinges on the area and the main upper shortwave trough ejects eastward. Strong vertical shear will be in place amid a very moist airmass. However, convection may remain elevated given poor timing with the diurnal cycle and impacts from daytime convection. If convection can become surface-based, damaging gusts will be possible. ...OK/KS to the Mid-MS Valley... Convection may be ongoing Saturday morning across parts of central MO. This activity may weaken during the morning, or slowly reintensify during the afternoon along outflow or the southward-advancing surface cold front. Additional convection is expected to develop along the sagging front across southern KS/northern OK during the late afternoon/evening. A couple of forward-propagating clusters are possible within this area of modest vertical shear, but rich boundary-layer moisture (dewpoints in the upper 60s/low 70s F) and moderate to strong instability. Isolated severe/damaging gusts and a few instances of hail will be possible with this activity. A corridor of higher probabilities may be needed in subsequent outlooks if confidence increases in location of better organized frontal convection. ...Central/Southern High Plains... Isolated convection is expected during the evening in a post-frontal upslope flow regime. Near 60 F surface dewpoints and steep midlevel lapse rates will support a corridor of moderate instability. While deep-layer flow will be light, vertically veering wind profiles will support 30-40 kt effective shear magnitudes amid a deeply mixed boundary-layer. Isolated strong to severe thunderstorms capable of strong gusts and hail will be possible. ...Northern IL into eastern WI and MI... Most forecast guidance is fairly sparse with convection across this area on Saturday. However, a very moist and unstable airmass will be in place ahead of the east/southeast-advancing cold front, along with favorable vertical shear for organized storms. Large-scale ascent will remain somewhat weak and ill-timed with the cold front progression, and low-level frontal convergence also will be poor. Severe probabilities have been adjusted some over the region based on low storm coverage and latest trends. However, a conditional severe threat will exist if storms develop. ..Leitman.. 06/28/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1222 PM CDT Fri Jun 28 2024 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM OHIO INTO PORTIONS WEST VIRGINIA...MARYLAND...PENNSYLVANIA AND NEW YORK... ...SUMMARY... Scattered damaging winds and a couple tornadoes are possible on Saturday from parts of Ohio into northern West Virginia/Maryland, central and western Pennsylvania, and western New York. ...Ohio Valley to the Northeast... Several vorticity maxima are forecast to migrate across the region within an area of enhanced southwesterly flow aloft ahead of the main upper shortwave trough progressing from the Upper Midwest to the lower Great Lakes. At the surface, low pressure will spread east/northeast from the upper Great Lakes into Ontario/Quebec. As this occurs, strong theta-e advection on southwesterly low-level flow will result in a very moist airmass spreading north/northeast from the Midwest into much of the Northeast. Early cloudiness and periods of showers may limit diurnal destabilization from eastern PA into NY. Pockets of stronger instability will overlap 30-40 kt westerly midlevel flow from parts of Ohio into western/central PA/NY. While midlevel lapse rates will remain quite poor, sufficient effective shear magnitudes amid rich boundary-layer moisture should support organized clusters and line segments capable of strong/damaging gusts. Vertically veering low-level winds will support somewhat enlarged and curved hodographs, with sufficient low-level instability and 0-1 km SRH. In addition to damaging gusts, a couple of tornadoes also will be possible. A more conditional risk may exist from late evening into the early overnight hours across parts of northern NY into VT as the surface front impinges on the area and the main upper shortwave trough ejects eastward. Strong vertical shear will be in place amid a very moist airmass. However, convection may remain elevated given poor timing with the diurnal cycle and impacts from daytime convection. If convection can become surface-based, damaging gusts will be possible. ...OK/KS to the Mid-MS Valley... Convection may be ongoing Saturday morning across parts of central MO. This activity may weaken during the morning, or slowly reintensify during the afternoon along outflow or the southward-advancing surface cold front. Additional convection is expected to develop along the sagging front across southern KS/northern OK during the late afternoon/evening. A couple of forward-propagating clusters are possible within this area of modest vertical shear, but rich boundary-layer moisture (dewpoints in the upper 60s/low 70s F) and moderate to strong instability. Isolated severe/damaging gusts and a few instances of hail will be possible with this activity. A corridor of higher probabilities may be needed in subsequent outlooks if confidence increases in location of better organized frontal convection. ...Central/Southern High Plains... Isolated convection is expected during the evening in a post-frontal upslope flow regime. Near 60 F surface dewpoints and steep midlevel lapse rates will support a corridor of moderate instability. While deep-layer flow will be light, vertically veering wind profiles will support 30-40 kt effective shear magnitudes amid a deeply mixed boundary-layer. Isolated strong to severe thunderstorms capable of strong gusts and hail will be possible. ...Northern IL into eastern WI and MI... Most forecast guidance is fairly sparse with convection across this area on Saturday. However, a very moist and unstable airmass will be in place ahead of the east/southeast-advancing cold front, along with favorable vertical shear for organized storms. Large-scale ascent will remain somewhat weak and ill-timed with the cold front progression, and low-level frontal convergence also will be poor. Severe probabilities have been adjusted some over the region based on low storm coverage and latest trends. However, a conditional severe threat will exist if storms develop. ..Leitman.. 06/28/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1222 PM CDT Fri Jun 28 2024 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM OHIO INTO PORTIONS WEST VIRGINIA...MARYLAND...PENNSYLVANIA AND NEW YORK... ...SUMMARY... Scattered damaging winds and a couple tornadoes are possible on Saturday from parts of Ohio into northern West Virginia/Maryland, central and western Pennsylvania, and western New York. ...Ohio Valley to the Northeast... Several vorticity maxima are forecast to migrate across the region within an area of enhanced southwesterly flow aloft ahead of the main upper shortwave trough progressing from the Upper Midwest to the lower Great Lakes. At the surface, low pressure will spread east/northeast from the upper Great Lakes into Ontario/Quebec. As this occurs, strong theta-e advection on southwesterly low-level flow will result in a very moist airmass spreading north/northeast from the Midwest into much of the Northeast. Early cloudiness and periods of showers may limit diurnal destabilization from eastern PA into NY. Pockets of stronger instability will overlap 30-40 kt westerly midlevel flow from parts of Ohio into western/central PA/NY. While midlevel lapse rates will remain quite poor, sufficient effective shear magnitudes amid rich boundary-layer moisture should support organized clusters and line segments capable of strong/damaging gusts. Vertically veering low-level winds will support somewhat enlarged and curved hodographs, with sufficient low-level instability and 0-1 km SRH. In addition to damaging gusts, a couple of tornadoes also will be possible. A more conditional risk may exist from late evening into the early overnight hours across parts of northern NY into VT as the surface front impinges on the area and the main upper shortwave trough ejects eastward. Strong vertical shear will be in place amid a very moist airmass. However, convection may remain elevated given poor timing with the diurnal cycle and impacts from daytime convection. If convection can become surface-based, damaging gusts will be possible. ...OK/KS to the Mid-MS Valley... Convection may be ongoing Saturday morning across parts of central MO. This activity may weaken during the morning, or slowly reintensify during the afternoon along outflow or the southward-advancing surface cold front. Additional convection is expected to develop along the sagging front across southern KS/northern OK during the late afternoon/evening. A couple of forward-propagating clusters are possible within this area of modest vertical shear, but rich boundary-layer moisture (dewpoints in the upper 60s/low 70s F) and moderate to strong instability. Isolated severe/damaging gusts and a few instances of hail will be possible with this activity. A corridor of higher probabilities may be needed in subsequent outlooks if confidence increases in location of better organized frontal convection. ...Central/Southern High Plains... Isolated convection is expected during the evening in a post-frontal upslope flow regime. Near 60 F surface dewpoints and steep midlevel lapse rates will support a corridor of moderate instability. While deep-layer flow will be light, vertically veering wind profiles will support 30-40 kt effective shear magnitudes amid a deeply mixed boundary-layer. Isolated strong to severe thunderstorms capable of strong gusts and hail will be possible. ...Northern IL into eastern WI and MI... Most forecast guidance is fairly sparse with convection across this area on Saturday. However, a very moist and unstable airmass will be in place ahead of the east/southeast-advancing cold front, along with favorable vertical shear for organized storms. Large-scale ascent will remain somewhat weak and ill-timed with the cold front progression, and low-level frontal convergence also will be poor. Severe probabilities have been adjusted some over the region based on low storm coverage and latest trends. However, a conditional severe threat will exist if storms develop. ..Leitman.. 06/28/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1222 PM CDT Fri Jun 28 2024 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM OHIO INTO PORTIONS WEST VIRGINIA...MARYLAND...PENNSYLVANIA AND NEW YORK... ...SUMMARY... Scattered damaging winds and a couple tornadoes are possible on Saturday from parts of Ohio into northern West Virginia/Maryland, central and western Pennsylvania, and western New York. ...Ohio Valley to the Northeast... Several vorticity maxima are forecast to migrate across the region within an area of enhanced southwesterly flow aloft ahead of the main upper shortwave trough progressing from the Upper Midwest to the lower Great Lakes. At the surface, low pressure will spread east/northeast from the upper Great Lakes into Ontario/Quebec. As this occurs, strong theta-e advection on southwesterly low-level flow will result in a very moist airmass spreading north/northeast from the Midwest into much of the Northeast. Early cloudiness and periods of showers may limit diurnal destabilization from eastern PA into NY. Pockets of stronger instability will overlap 30-40 kt westerly midlevel flow from parts of Ohio into western/central PA/NY. While midlevel lapse rates will remain quite poor, sufficient effective shear magnitudes amid rich boundary-layer moisture should support organized clusters and line segments capable of strong/damaging gusts. Vertically veering low-level winds will support somewhat enlarged and curved hodographs, with sufficient low-level instability and 0-1 km SRH. In addition to damaging gusts, a couple of tornadoes also will be possible. A more conditional risk may exist from late evening into the early overnight hours across parts of northern NY into VT as the surface front impinges on the area and the main upper shortwave trough ejects eastward. Strong vertical shear will be in place amid a very moist airmass. However, convection may remain elevated given poor timing with the diurnal cycle and impacts from daytime convection. If convection can become surface-based, damaging gusts will be possible. ...OK/KS to the Mid-MS Valley... Convection may be ongoing Saturday morning across parts of central MO. This activity may weaken during the morning, or slowly reintensify during the afternoon along outflow or the southward-advancing surface cold front. Additional convection is expected to develop along the sagging front across southern KS/northern OK during the late afternoon/evening. A couple of forward-propagating clusters are possible within this area of modest vertical shear, but rich boundary-layer moisture (dewpoints in the upper 60s/low 70s F) and moderate to strong instability. Isolated severe/damaging gusts and a few instances of hail will be possible with this activity. A corridor of higher probabilities may be needed in subsequent outlooks if confidence increases in location of better organized frontal convection. ...Central/Southern High Plains... Isolated convection is expected during the evening in a post-frontal upslope flow regime. Near 60 F surface dewpoints and steep midlevel lapse rates will support a corridor of moderate instability. While deep-layer flow will be light, vertically veering wind profiles will support 30-40 kt effective shear magnitudes amid a deeply mixed boundary-layer. Isolated strong to severe thunderstorms capable of strong gusts and hail will be possible. ...Northern IL into eastern WI and MI... Most forecast guidance is fairly sparse with convection across this area on Saturday. However, a very moist and unstable airmass will be in place ahead of the east/southeast-advancing cold front, along with favorable vertical shear for organized storms. Large-scale ascent will remain somewhat weak and ill-timed with the cold front progression, and low-level frontal convergence also will be poor. Severe probabilities have been adjusted some over the region based on low storm coverage and latest trends. However, a conditional severe threat will exist if storms develop. ..Leitman.. 06/28/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1222 PM CDT Fri Jun 28 2024 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM OHIO INTO PORTIONS WEST VIRGINIA...MARYLAND...PENNSYLVANIA AND NEW YORK... ...SUMMARY... Scattered damaging winds and a couple tornadoes are possible on Saturday from parts of Ohio into northern West Virginia/Maryland, central and western Pennsylvania, and western New York. ...Ohio Valley to the Northeast... Several vorticity maxima are forecast to migrate across the region within an area of enhanced southwesterly flow aloft ahead of the main upper shortwave trough progressing from the Upper Midwest to the lower Great Lakes. At the surface, low pressure will spread east/northeast from the upper Great Lakes into Ontario/Quebec. As this occurs, strong theta-e advection on southwesterly low-level flow will result in a very moist airmass spreading north/northeast from the Midwest into much of the Northeast. Early cloudiness and periods of showers may limit diurnal destabilization from eastern PA into NY. Pockets of stronger instability will overlap 30-40 kt westerly midlevel flow from parts of Ohio into western/central PA/NY. While midlevel lapse rates will remain quite poor, sufficient effective shear magnitudes amid rich boundary-layer moisture should support organized clusters and line segments capable of strong/damaging gusts. Vertically veering low-level winds will support somewhat enlarged and curved hodographs, with sufficient low-level instability and 0-1 km SRH. In addition to damaging gusts, a couple of tornadoes also will be possible. A more conditional risk may exist from late evening into the early overnight hours across parts of northern NY into VT as the surface front impinges on the area and the main upper shortwave trough ejects eastward. Strong vertical shear will be in place amid a very moist airmass. However, convection may remain elevated given poor timing with the diurnal cycle and impacts from daytime convection. If convection can become surface-based, damaging gusts will be possible. ...OK/KS to the Mid-MS Valley... Convection may be ongoing Saturday morning across parts of central MO. This activity may weaken during the morning, or slowly reintensify during the afternoon along outflow or the southward-advancing surface cold front. Additional convection is expected to develop along the sagging front across southern KS/northern OK during the late afternoon/evening. A couple of forward-propagating clusters are possible within this area of modest vertical shear, but rich boundary-layer moisture (dewpoints in the upper 60s/low 70s F) and moderate to strong instability. Isolated severe/damaging gusts and a few instances of hail will be possible with this activity. A corridor of higher probabilities may be needed in subsequent outlooks if confidence increases in location of better organized frontal convection. ...Central/Southern High Plains... Isolated convection is expected during the evening in a post-frontal upslope flow regime. Near 60 F surface dewpoints and steep midlevel lapse rates will support a corridor of moderate instability. While deep-layer flow will be light, vertically veering wind profiles will support 30-40 kt effective shear magnitudes amid a deeply mixed boundary-layer. Isolated strong to severe thunderstorms capable of strong gusts and hail will be possible. ...Northern IL into eastern WI and MI... Most forecast guidance is fairly sparse with convection across this area on Saturday. However, a very moist and unstable airmass will be in place ahead of the east/southeast-advancing cold front, along with favorable vertical shear for organized storms. Large-scale ascent will remain somewhat weak and ill-timed with the cold front progression, and low-level frontal convergence also will be poor. Severe probabilities have been adjusted some over the region based on low storm coverage and latest trends. However, a conditional severe threat will exist if storms develop. ..Leitman.. 06/28/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1222 PM CDT Fri Jun 28 2024 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM OHIO INTO PORTIONS WEST VIRGINIA...MARYLAND...PENNSYLVANIA AND NEW YORK... ...SUMMARY... Scattered damaging winds and a couple tornadoes are possible on Saturday from parts of Ohio into northern West Virginia/Maryland, central and western Pennsylvania, and western New York. ...Ohio Valley to the Northeast... Several vorticity maxima are forecast to migrate across the region within an area of enhanced southwesterly flow aloft ahead of the main upper shortwave trough progressing from the Upper Midwest to the lower Great Lakes. At the surface, low pressure will spread east/northeast from the upper Great Lakes into Ontario/Quebec. As this occurs, strong theta-e advection on southwesterly low-level flow will result in a very moist airmass spreading north/northeast from the Midwest into much of the Northeast. Early cloudiness and periods of showers may limit diurnal destabilization from eastern PA into NY. Pockets of stronger instability will overlap 30-40 kt westerly midlevel flow from parts of Ohio into western/central PA/NY. While midlevel lapse rates will remain quite poor, sufficient effective shear magnitudes amid rich boundary-layer moisture should support organized clusters and line segments capable of strong/damaging gusts. Vertically veering low-level winds will support somewhat enlarged and curved hodographs, with sufficient low-level instability and 0-1 km SRH. In addition to damaging gusts, a couple of tornadoes also will be possible. A more conditional risk may exist from late evening into the early overnight hours across parts of northern NY into VT as the surface front impinges on the area and the main upper shortwave trough ejects eastward. Strong vertical shear will be in place amid a very moist airmass. However, convection may remain elevated given poor timing with the diurnal cycle and impacts from daytime convection. If convection can become surface-based, damaging gusts will be possible. ...OK/KS to the Mid-MS Valley... Convection may be ongoing Saturday morning across parts of central MO. This activity may weaken during the morning, or slowly reintensify during the afternoon along outflow or the southward-advancing surface cold front. Additional convection is expected to develop along the sagging front across southern KS/northern OK during the late afternoon/evening. A couple of forward-propagating clusters are possible within this area of modest vertical shear, but rich boundary-layer moisture (dewpoints in the upper 60s/low 70s F) and moderate to strong instability. Isolated severe/damaging gusts and a few instances of hail will be possible with this activity. A corridor of higher probabilities may be needed in subsequent outlooks if confidence increases in location of better organized frontal convection. ...Central/Southern High Plains... Isolated convection is expected during the evening in a post-frontal upslope flow regime. Near 60 F surface dewpoints and steep midlevel lapse rates will support a corridor of moderate instability. While deep-layer flow will be light, vertically veering wind profiles will support 30-40 kt effective shear magnitudes amid a deeply mixed boundary-layer. Isolated strong to severe thunderstorms capable of strong gusts and hail will be possible. ...Northern IL into eastern WI and MI... Most forecast guidance is fairly sparse with convection across this area on Saturday. However, a very moist and unstable airmass will be in place ahead of the east/southeast-advancing cold front, along with favorable vertical shear for organized storms. Large-scale ascent will remain somewhat weak and ill-timed with the cold front progression, and low-level frontal convergence also will be poor. Severe probabilities have been adjusted some over the region based on low storm coverage and latest trends. However, a conditional severe threat will exist if storms develop. ..Leitman.. 06/28/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1222 PM CDT Fri Jun 28 2024 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM OHIO INTO PORTIONS WEST VIRGINIA...MARYLAND...PENNSYLVANIA AND NEW YORK... ...SUMMARY... Scattered damaging winds and a couple tornadoes are possible on Saturday from parts of Ohio into northern West Virginia/Maryland, central and western Pennsylvania, and western New York. ...Ohio Valley to the Northeast... Several vorticity maxima are forecast to migrate across the region within an area of enhanced southwesterly flow aloft ahead of the main upper shortwave trough progressing from the Upper Midwest to the lower Great Lakes. At the surface, low pressure will spread east/northeast from the upper Great Lakes into Ontario/Quebec. As this occurs, strong theta-e advection on southwesterly low-level flow will result in a very moist airmass spreading north/northeast from the Midwest into much of the Northeast. Early cloudiness and periods of showers may limit diurnal destabilization from eastern PA into NY. Pockets of stronger instability will overlap 30-40 kt westerly midlevel flow from parts of Ohio into western/central PA/NY. While midlevel lapse rates will remain quite poor, sufficient effective shear magnitudes amid rich boundary-layer moisture should support organized clusters and line segments capable of strong/damaging gusts. Vertically veering low-level winds will support somewhat enlarged and curved hodographs, with sufficient low-level instability and 0-1 km SRH. In addition to damaging gusts, a couple of tornadoes also will be possible. A more conditional risk may exist from late evening into the early overnight hours across parts of northern NY into VT as the surface front impinges on the area and the main upper shortwave trough ejects eastward. Strong vertical shear will be in place amid a very moist airmass. However, convection may remain elevated given poor timing with the diurnal cycle and impacts from daytime convection. If convection can become surface-based, damaging gusts will be possible. ...OK/KS to the Mid-MS Valley... Convection may be ongoing Saturday morning across parts of central MO. This activity may weaken during the morning, or slowly reintensify during the afternoon along outflow or the southward-advancing surface cold front. Additional convection is expected to develop along the sagging front across southern KS/northern OK during the late afternoon/evening. A couple of forward-propagating clusters are possible within this area of modest vertical shear, but rich boundary-layer moisture (dewpoints in the upper 60s/low 70s F) and moderate to strong instability. Isolated severe/damaging gusts and a few instances of hail will be possible with this activity. A corridor of higher probabilities may be needed in subsequent outlooks if confidence increases in location of better organized frontal convection. ...Central/Southern High Plains... Isolated convection is expected during the evening in a post-frontal upslope flow regime. Near 60 F surface dewpoints and steep midlevel lapse rates will support a corridor of moderate instability. While deep-layer flow will be light, vertically veering wind profiles will support 30-40 kt effective shear magnitudes amid a deeply mixed boundary-layer. Isolated strong to severe thunderstorms capable of strong gusts and hail will be possible. ...Northern IL into eastern WI and MI... Most forecast guidance is fairly sparse with convection across this area on Saturday. However, a very moist and unstable airmass will be in place ahead of the east/southeast-advancing cold front, along with favorable vertical shear for organized storms. Large-scale ascent will remain somewhat weak and ill-timed with the cold front progression, and low-level frontal convergence also will be poor. Severe probabilities have been adjusted some over the region based on low storm coverage and latest trends. However, a conditional severe threat will exist if storms develop. ..Leitman.. 06/28/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1222 PM CDT Fri Jun 28 2024 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM OHIO INTO PORTIONS WEST VIRGINIA...MARYLAND...PENNSYLVANIA AND NEW YORK... ...SUMMARY... Scattered damaging winds and a couple tornadoes are possible on Saturday from parts of Ohio into northern West Virginia/Maryland, central and western Pennsylvania, and western New York. ...Ohio Valley to the Northeast... Several vorticity maxima are forecast to migrate across the region within an area of enhanced southwesterly flow aloft ahead of the main upper shortwave trough progressing from the Upper Midwest to the lower Great Lakes. At the surface, low pressure will spread east/northeast from the upper Great Lakes into Ontario/Quebec. As this occurs, strong theta-e advection on southwesterly low-level flow will result in a very moist airmass spreading north/northeast from the Midwest into much of the Northeast. Early cloudiness and periods of showers may limit diurnal destabilization from eastern PA into NY. Pockets of stronger instability will overlap 30-40 kt westerly midlevel flow from parts of Ohio into western/central PA/NY. While midlevel lapse rates will remain quite poor, sufficient effective shear magnitudes amid rich boundary-layer moisture should support organized clusters and line segments capable of strong/damaging gusts. Vertically veering low-level winds will support somewhat enlarged and curved hodographs, with sufficient low-level instability and 0-1 km SRH. In addition to damaging gusts, a couple of tornadoes also will be possible. A more conditional risk may exist from late evening into the early overnight hours across parts of northern NY into VT as the surface front impinges on the area and the main upper shortwave trough ejects eastward. Strong vertical shear will be in place amid a very moist airmass. However, convection may remain elevated given poor timing with the diurnal cycle and impacts from daytime convection. If convection can become surface-based, damaging gusts will be possible. ...OK/KS to the Mid-MS Valley... Convection may be ongoing Saturday morning across parts of central MO. This activity may weaken during the morning, or slowly reintensify during the afternoon along outflow or the southward-advancing surface cold front. Additional convection is expected to develop along the sagging front across southern KS/northern OK during the late afternoon/evening. A couple of forward-propagating clusters are possible within this area of modest vertical shear, but rich boundary-layer moisture (dewpoints in the upper 60s/low 70s F) and moderate to strong instability. Isolated severe/damaging gusts and a few instances of hail will be possible with this activity. A corridor of higher probabilities may be needed in subsequent outlooks if confidence increases in location of better organized frontal convection. ...Central/Southern High Plains... Isolated convection is expected during the evening in a post-frontal upslope flow regime. Near 60 F surface dewpoints and steep midlevel lapse rates will support a corridor of moderate instability. While deep-layer flow will be light, vertically veering wind profiles will support 30-40 kt effective shear magnitudes amid a deeply mixed boundary-layer. Isolated strong to severe thunderstorms capable of strong gusts and hail will be possible. ...Northern IL into eastern WI and MI... Most forecast guidance is fairly sparse with convection across this area on Saturday. However, a very moist and unstable airmass will be in place ahead of the east/southeast-advancing cold front, along with favorable vertical shear for organized storms. Large-scale ascent will remain somewhat weak and ill-timed with the cold front progression, and low-level frontal convergence also will be poor. Severe probabilities have been adjusted some over the region based on low storm coverage and latest trends. However, a conditional severe threat will exist if storms develop. ..Leitman.. 06/28/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Fri Jun 28 2024 Valid 281630Z - 291200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL PLAINS TO THE MID MISSISSIPPI VALLEY... ...SUMMARY... Large hail, damaging winds, and a couple of tornadoes may occur from parts of the central Plains into the mid/upper Mississippi Valley this afternoon and tonight. ...Synopsis... An upper low over the northern Rockies/High Plains will progress eastward today to the Upper Midwest. At the surface, an occluded low is forecast to meander slowly eastward over northern MN through this evening, while a secondary low consolidates over central KS. An occluded/cold front extending from the northern MN low will develop slowly southeastward across the central Plains and mid MO Valley this afternoon. This boundary will likely serve as a focus for strong/severe convection later today. ...Central Plains into the Mid Mississippi Valley... Better forcing for ascent associated with the upper trough/low should generally remain displaced to the north of the central Plains and mid MO Valley through much of the day. Also, the lingering effect of morning clouds/precipitation will be to slow diurnal destabilization to some extent. Still, low-level convergence along the cold front and glancing large-scale ascent will probably be sufficient for convective initiation through 20-00Z across parts of IA into eastern NE, and northeast KS into northern MO. Even modest daytime heating of the moist low-level airmass ahead of the front will support a narrow corridor of moderate to locally strong instability. Strengthening westerly winds through mid/upper levels will foster strong deep-layer shear and updraft organization. Initial development along the cold front from eastern NE into central IA may be supercellular, with an associated threat for large hail. Upscale growth into clusters and short line segments with a greater severe/damaging wind threat seems probable with time this evening. The eastern extent of the severe risk across the mid MS Valley will be modulated by the narrow zone of stronger instability, and convection should gradually weaken as it continues eastward late this evening and overnight. The tornado threat across these areas today appears less clear. While a modest southwesterly low-level jet will aid in sufficient low-level shear for updraft rotation, it remains unclear whether multiple supercells will be able to persist into the early evening hours. Still, some threat for a couple tornadoes remains apparent, mainly near/northeast of the surface low in northeast KS and vicinity where low-level shear should be locally maximized. A separate area of high-based convective development should occur this afternoon across the central High Plains, along/north of the cold front in a weak low-level upslope flow regime. This activity will move generally east-southeastward through the evening through a very well-mixed boundary layer, with generally weak to moderate instability present. Although low-level winds should remain modest, gradually increasing westerly flow at mid/upper levels should support sufficient deep-layer shear for convective organization. Severe/damaging winds appear to be the main threat as one or more small clusters continue east-southeastward across western/central NE/KS late this afternoon and evening. Isolated gusts of 75+ mph may occur if convection can become well organized into a small bowing cluster. Some large hail also appears possible, particularly with any initial supercells. ...Northern Plains into the Upper Mississippi Valley... Isolated to scattered thunderstorms should develop along an occluded front extending into parts of ND as the upper trough/low moves eastward over the northern Plains today. While instability appears fairly modest, occasional hail and strong/gusty winds may occur with the more robust convection given the presence of sufficient deep-layer shear. ..Gleason/Thornton.. 06/28/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Fri Jun 28 2024 Valid 281630Z - 291200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL PLAINS TO THE MID MISSISSIPPI VALLEY... ...SUMMARY... Large hail, damaging winds, and a couple of tornadoes may occur from parts of the central Plains into the mid/upper Mississippi Valley this afternoon and tonight. ...Synopsis... An upper low over the northern Rockies/High Plains will progress eastward today to the Upper Midwest. At the surface, an occluded low is forecast to meander slowly eastward over northern MN through this evening, while a secondary low consolidates over central KS. An occluded/cold front extending from the northern MN low will develop slowly southeastward across the central Plains and mid MO Valley this afternoon. This boundary will likely serve as a focus for strong/severe convection later today. ...Central Plains into the Mid Mississippi Valley... Better forcing for ascent associated with the upper trough/low should generally remain displaced to the north of the central Plains and mid MO Valley through much of the day. Also, the lingering effect of morning clouds/precipitation will be to slow diurnal destabilization to some extent. Still, low-level convergence along the cold front and glancing large-scale ascent will probably be sufficient for convective initiation through 20-00Z across parts of IA into eastern NE, and northeast KS into northern MO. Even modest daytime heating of the moist low-level airmass ahead of the front will support a narrow corridor of moderate to locally strong instability. Strengthening westerly winds through mid/upper levels will foster strong deep-layer shear and updraft organization. Initial development along the cold front from eastern NE into central IA may be supercellular, with an associated threat for large hail. Upscale growth into clusters and short line segments with a greater severe/damaging wind threat seems probable with time this evening. The eastern extent of the severe risk across the mid MS Valley will be modulated by the narrow zone of stronger instability, and convection should gradually weaken as it continues eastward late this evening and overnight. The tornado threat across these areas today appears less clear. While a modest southwesterly low-level jet will aid in sufficient low-level shear for updraft rotation, it remains unclear whether multiple supercells will be able to persist into the early evening hours. Still, some threat for a couple tornadoes remains apparent, mainly near/northeast of the surface low in northeast KS and vicinity where low-level shear should be locally maximized. A separate area of high-based convective development should occur this afternoon across the central High Plains, along/north of the cold front in a weak low-level upslope flow regime. This activity will move generally east-southeastward through the evening through a very well-mixed boundary layer, with generally weak to moderate instability present. Although low-level winds should remain modest, gradually increasing westerly flow at mid/upper levels should support sufficient deep-layer shear for convective organization. Severe/damaging winds appear to be the main threat as one or more small clusters continue east-southeastward across western/central NE/KS late this afternoon and evening. Isolated gusts of 75+ mph may occur if convection can become well organized into a small bowing cluster. Some large hail also appears possible, particularly with any initial supercells. ...Northern Plains into the Upper Mississippi Valley... Isolated to scattered thunderstorms should develop along an occluded front extending into parts of ND as the upper trough/low moves eastward over the northern Plains today. While instability appears fairly modest, occasional hail and strong/gusty winds may occur with the more robust convection given the presence of sufficient deep-layer shear. ..Gleason/Thornton.. 06/28/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Fri Jun 28 2024 Valid 281630Z - 291200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL PLAINS TO THE MID MISSISSIPPI VALLEY... ...SUMMARY... Large hail, damaging winds, and a couple of tornadoes may occur from parts of the central Plains into the mid/upper Mississippi Valley this afternoon and tonight. ...Synopsis... An upper low over the northern Rockies/High Plains will progress eastward today to the Upper Midwest. At the surface, an occluded low is forecast to meander slowly eastward over northern MN through this evening, while a secondary low consolidates over central KS. An occluded/cold front extending from the northern MN low will develop slowly southeastward across the central Plains and mid MO Valley this afternoon. This boundary will likely serve as a focus for strong/severe convection later today. ...Central Plains into the Mid Mississippi Valley... Better forcing for ascent associated with the upper trough/low should generally remain displaced to the north of the central Plains and mid MO Valley through much of the day. Also, the lingering effect of morning clouds/precipitation will be to slow diurnal destabilization to some extent. Still, low-level convergence along the cold front and glancing large-scale ascent will probably be sufficient for convective initiation through 20-00Z across parts of IA into eastern NE, and northeast KS into northern MO. Even modest daytime heating of the moist low-level airmass ahead of the front will support a narrow corridor of moderate to locally strong instability. Strengthening westerly winds through mid/upper levels will foster strong deep-layer shear and updraft organization. Initial development along the cold front from eastern NE into central IA may be supercellular, with an associated threat for large hail. Upscale growth into clusters and short line segments with a greater severe/damaging wind threat seems probable with time this evening. The eastern extent of the severe risk across the mid MS Valley will be modulated by the narrow zone of stronger instability, and convection should gradually weaken as it continues eastward late this evening and overnight. The tornado threat across these areas today appears less clear. While a modest southwesterly low-level jet will aid in sufficient low-level shear for updraft rotation, it remains unclear whether multiple supercells will be able to persist into the early evening hours. Still, some threat for a couple tornadoes remains apparent, mainly near/northeast of the surface low in northeast KS and vicinity where low-level shear should be locally maximized. A separate area of high-based convective development should occur this afternoon across the central High Plains, along/north of the cold front in a weak low-level upslope flow regime. This activity will move generally east-southeastward through the evening through a very well-mixed boundary layer, with generally weak to moderate instability present. Although low-level winds should remain modest, gradually increasing westerly flow at mid/upper levels should support sufficient deep-layer shear for convective organization. Severe/damaging winds appear to be the main threat as one or more small clusters continue east-southeastward across western/central NE/KS late this afternoon and evening. Isolated gusts of 75+ mph may occur if convection can become well organized into a small bowing cluster. Some large hail also appears possible, particularly with any initial supercells. ...Northern Plains into the Upper Mississippi Valley... Isolated to scattered thunderstorms should develop along an occluded front extending into parts of ND as the upper trough/low moves eastward over the northern Plains today. While instability appears fairly modest, occasional hail and strong/gusty winds may occur with the more robust convection given the presence of sufficient deep-layer shear. ..Gleason/Thornton.. 06/28/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Fri Jun 28 2024 Valid 281630Z - 291200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL PLAINS TO THE MID MISSISSIPPI VALLEY... ...SUMMARY... Large hail, damaging winds, and a couple of tornadoes may occur from parts of the central Plains into the mid/upper Mississippi Valley this afternoon and tonight. ...Synopsis... An upper low over the northern Rockies/High Plains will progress eastward today to the Upper Midwest. At the surface, an occluded low is forecast to meander slowly eastward over northern MN through this evening, while a secondary low consolidates over central KS. An occluded/cold front extending from the northern MN low will develop slowly southeastward across the central Plains and mid MO Valley this afternoon. This boundary will likely serve as a focus for strong/severe convection later today. ...Central Plains into the Mid Mississippi Valley... Better forcing for ascent associated with the upper trough/low should generally remain displaced to the north of the central Plains and mid MO Valley through much of the day. Also, the lingering effect of morning clouds/precipitation will be to slow diurnal destabilization to some extent. Still, low-level convergence along the cold front and glancing large-scale ascent will probably be sufficient for convective initiation through 20-00Z across parts of IA into eastern NE, and northeast KS into northern MO. Even modest daytime heating of the moist low-level airmass ahead of the front will support a narrow corridor of moderate to locally strong instability. Strengthening westerly winds through mid/upper levels will foster strong deep-layer shear and updraft organization. Initial development along the cold front from eastern NE into central IA may be supercellular, with an associated threat for large hail. Upscale growth into clusters and short line segments with a greater severe/damaging wind threat seems probable with time this evening. The eastern extent of the severe risk across the mid MS Valley will be modulated by the narrow zone of stronger instability, and convection should gradually weaken as it continues eastward late this evening and overnight. The tornado threat across these areas today appears less clear. While a modest southwesterly low-level jet will aid in sufficient low-level shear for updraft rotation, it remains unclear whether multiple supercells will be able to persist into the early evening hours. Still, some threat for a couple tornadoes remains apparent, mainly near/northeast of the surface low in northeast KS and vicinity where low-level shear should be locally maximized. A separate area of high-based convective development should occur this afternoon across the central High Plains, along/north of the cold front in a weak low-level upslope flow regime. This activity will move generally east-southeastward through the evening through a very well-mixed boundary layer, with generally weak to moderate instability present. Although low-level winds should remain modest, gradually increasing westerly flow at mid/upper levels should support sufficient deep-layer shear for convective organization. Severe/damaging winds appear to be the main threat as one or more small clusters continue east-southeastward across western/central NE/KS late this afternoon and evening. Isolated gusts of 75+ mph may occur if convection can become well organized into a small bowing cluster. Some large hail also appears possible, particularly with any initial supercells. ...Northern Plains into the Upper Mississippi Valley... Isolated to scattered thunderstorms should develop along an occluded front extending into parts of ND as the upper trough/low moves eastward over the northern Plains today. While instability appears fairly modest, occasional hail and strong/gusty winds may occur with the more robust convection given the presence of sufficient deep-layer shear. ..Gleason/Thornton.. 06/28/2024 Read more