Severe Storms

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1142 AM CDT Wed Jul 03 2024 Valid 031700Z - 041200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHERN IDAHO... ...CRITICAL FIRE WEATHER AREA FOR EAST-CENTRAL UTAH... ...17Z Update... Elevated highlights for the Sacramento Valley and much of the Great Basin into the Central Rockies have been maintained, with fire weather conditions in the Sacramento Valley expected to diminish by 21-22Z. Much of Eastern Oregon into portions of Northwestern Nevada were removed from the Elevated highlight area due to increasing confidence that surface winds will remain below the 15 MPH criteria. However, locally elevated conditions are possible with surface conditions expected to be hot and dry. The Critical highlight over Southern Idaho has been maintained, with gusts of 25-30 MPH already observed this morning. Relative humidity is anticipated to drop below 15% during the afternoon with fuels that are modestly receptive to wildfire spread. A Critical area was introduced for much of East-Central Utah into the Upper Colorado River Basin. HREF guidance has increased confidence in RH < 15% and wind gusts > 25 MPH occurring, with fuels receptive to wildfire spread, particularly with southwestward extent. ..Halbert/Lyons.. 07/03/2024 .PREV DISCUSSION... /ISSUED 0158 AM CDT Wed Jul 03 2024/ ...Synopsis... A mid-level trough will overspread the northern Rockies while upper ridging prevails across much of the CONUS today. Adequate upper-support associated with the passing mid-level trough will encourage dry and windy conditions across portions of northern California and the northern Great Basin toward the central Rockies. Portions of the Sacramento Valley in California will be the first region impacted by fire weather conditions. 15+ mph sustained northerly surface winds should already be ongoing by the morning hours, with RH decreasing to 15 percent by late morning into early afternoon. Elevated highlights were added to parts of the Sacramento Valley given receptive fuels in the area. 15+ mph sustained westerly surface winds will also overlap with a large area of RH dropping below 15 percent across parts of the Great Basin into the central Rockies. Fuels are also receptive to wildfire spread in this region, warranting the maintenance of Elevated highlights. Critical highlights have also been maintained across portions of the Snake River Plain in southern Idaho, where westerly surface winds may sustain well above 20 mph for at least a few hours around afternoon peak heating. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1142 AM CDT Wed Jul 03 2024 Valid 031700Z - 041200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHERN IDAHO... ...CRITICAL FIRE WEATHER AREA FOR EAST-CENTRAL UTAH... ...17Z Update... Elevated highlights for the Sacramento Valley and much of the Great Basin into the Central Rockies have been maintained, with fire weather conditions in the Sacramento Valley expected to diminish by 21-22Z. Much of Eastern Oregon into portions of Northwestern Nevada were removed from the Elevated highlight area due to increasing confidence that surface winds will remain below the 15 MPH criteria. However, locally elevated conditions are possible with surface conditions expected to be hot and dry. The Critical highlight over Southern Idaho has been maintained, with gusts of 25-30 MPH already observed this morning. Relative humidity is anticipated to drop below 15% during the afternoon with fuels that are modestly receptive to wildfire spread. A Critical area was introduced for much of East-Central Utah into the Upper Colorado River Basin. HREF guidance has increased confidence in RH < 15% and wind gusts > 25 MPH occurring, with fuels receptive to wildfire spread, particularly with southwestward extent. ..Halbert/Lyons.. 07/03/2024 .PREV DISCUSSION... /ISSUED 0158 AM CDT Wed Jul 03 2024/ ...Synopsis... A mid-level trough will overspread the northern Rockies while upper ridging prevails across much of the CONUS today. Adequate upper-support associated with the passing mid-level trough will encourage dry and windy conditions across portions of northern California and the northern Great Basin toward the central Rockies. Portions of the Sacramento Valley in California will be the first region impacted by fire weather conditions. 15+ mph sustained northerly surface winds should already be ongoing by the morning hours, with RH decreasing to 15 percent by late morning into early afternoon. Elevated highlights were added to parts of the Sacramento Valley given receptive fuels in the area. 15+ mph sustained westerly surface winds will also overlap with a large area of RH dropping below 15 percent across parts of the Great Basin into the central Rockies. Fuels are also receptive to wildfire spread in this region, warranting the maintenance of Elevated highlights. Critical highlights have also been maintained across portions of the Snake River Plain in southern Idaho, where westerly surface winds may sustain well above 20 mph for at least a few hours around afternoon peak heating. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1142 AM CDT Wed Jul 03 2024 Valid 031700Z - 041200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHERN IDAHO... ...CRITICAL FIRE WEATHER AREA FOR EAST-CENTRAL UTAH... ...17Z Update... Elevated highlights for the Sacramento Valley and much of the Great Basin into the Central Rockies have been maintained, with fire weather conditions in the Sacramento Valley expected to diminish by 21-22Z. Much of Eastern Oregon into portions of Northwestern Nevada were removed from the Elevated highlight area due to increasing confidence that surface winds will remain below the 15 MPH criteria. However, locally elevated conditions are possible with surface conditions expected to be hot and dry. The Critical highlight over Southern Idaho has been maintained, with gusts of 25-30 MPH already observed this morning. Relative humidity is anticipated to drop below 15% during the afternoon with fuels that are modestly receptive to wildfire spread. A Critical area was introduced for much of East-Central Utah into the Upper Colorado River Basin. HREF guidance has increased confidence in RH < 15% and wind gusts > 25 MPH occurring, with fuels receptive to wildfire spread, particularly with southwestward extent. ..Halbert/Lyons.. 07/03/2024 .PREV DISCUSSION... /ISSUED 0158 AM CDT Wed Jul 03 2024/ ...Synopsis... A mid-level trough will overspread the northern Rockies while upper ridging prevails across much of the CONUS today. Adequate upper-support associated with the passing mid-level trough will encourage dry and windy conditions across portions of northern California and the northern Great Basin toward the central Rockies. Portions of the Sacramento Valley in California will be the first region impacted by fire weather conditions. 15+ mph sustained northerly surface winds should already be ongoing by the morning hours, with RH decreasing to 15 percent by late morning into early afternoon. Elevated highlights were added to parts of the Sacramento Valley given receptive fuels in the area. 15+ mph sustained westerly surface winds will also overlap with a large area of RH dropping below 15 percent across parts of the Great Basin into the central Rockies. Fuels are also receptive to wildfire spread in this region, warranting the maintenance of Elevated highlights. Critical highlights have also been maintained across portions of the Snake River Plain in southern Idaho, where westerly surface winds may sustain well above 20 mph for at least a few hours around afternoon peak heating. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Wed Jul 03 2024 Valid 031630Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS...AND THE OZARKS INTO PORTIONS OF THE OHIO VALLEY... ...SUMMARY... Scattered severe thunderstorms appear possible this afternoon and evening across parts of the northern/central High Plains, and from the Ozarks into the Ohio Valley. The most favorable corridor for isolated very large hail and significant severe wind gusts is centered on the central High Plains. ...Synopsis... An upper trough will continue moving eastward across Ontario and the Great Lakes today, while an upper high remains centered over the Southeast. Farther west, a separate mid-level shortwave trough will advance east-southeastward from the northern Rockies to the northern/central High Plains through tonight. Multiple convectively augmented mid-level vorticity maxima will move generally east-northeastward across the central Plains into the mid MS and OH Valleys. At the surface, a cold front extends from the OH Valley southwestward to the southern Plains. Weak lee cyclogenesis is forecast to occur across the central High Plains through late this afternoon, and modest low-level moisture return is anticipated to the north of the front and east of a weak surface lee trough across parts of the northern/central Plains. ...Northern/Central Plains... Morning clouds and lingering convection across parts of the central Plains will hamper the development of instability today, especially with eastward extent into NE/KS. Even so, pockets of filtered daytime heating will occur across the northern/central High Plains along and east of the surface lee trough. With steepened mid-level lapse rates present over eastern CO/WY into western SD/NE, a narrow zone of moderate instability is forecast to be in place prior to robust convective initiation this afternoon. Initial development should occur along the length of the lee trough from parts of western NE into eastern CO. A somewhat separate area of convection may also develop from northeastern WY to the Black Hills, as large-scale ascent preceding the mid-level shortwave trough overspreads this region. Modest low-level east-southeasterly flow will quickly veer to westerly at mid/upper levels, with some strengthening and hodograph elongation. Corresponding strong deep-layer shear will support supercells initially, with attendant threat for large hail. Given relatively cool temperatures aloft and the presence of steep mid-level lapse rates, isolated very large hail greater than 2 inches in diameter appears possible. A small zone with favorable overlap of moderate instability, strong deep-layer shear, and sufficient low-level shear remains apparent over parts of the NE Panhandle into northwest NE. This area may have a locally greater threat for a couple of tornadoes with any supercells that can persist late this afternoon into the early evening, assuming the boundary layer does not become too well mixed. Otherwise, upscale growth/clustering appears probable this evening as convective outflows aggregate into the central Plains. Severe/damaging winds should become the main threat as this occurs, with isolated significant gusts up to 75 mph possible if a more consolidated bow/MCS can develop. Confidence in this occurring still remains somewhat low, but the best chance for a more concentrated corridor of severe winds remains across parts of eastern CO into southwest NE and northwest KS this evening. ...Ozarks to the Ohio Valley... A rather moist low-level airmass remains present along/south of the front today, with surface dewpoints generally in the low to mid 70s, and precipitable water values around 1.75-2.2 inches. A fair amount of convective cloud debris is present along/near the front across the mid MS Valley. This will tend to slow diurnal destabilization to some extent across this area. Mid-level lapse rates are also expected to remain poor. Still, moderate to locally strong instability and steepened low-level lapse rates are forecast to develop through peak afternoon heating along/south of the front, which will extend from the Ozarks northeastward into parts of the OH Valley. Low-level winds are expected to remain generally weak, but a modest increase in southwesterly winds at mid levels should foster sufficient deep-layer shear to support some updraft organization. Mainly multicell clusters should develop this afternoon, focused along the front. Some of this activity may produce scattered damaging winds through early evening before eventually weakening. Morning guidance shows a greater concentration of thunderstorms with clustering potential across the Ozarks into the mid MS Valley. ..Gleason/Thornton.. 07/03/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Wed Jul 03 2024 Valid 031630Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS...AND THE OZARKS INTO PORTIONS OF THE OHIO VALLEY... ...SUMMARY... Scattered severe thunderstorms appear possible this afternoon and evening across parts of the northern/central High Plains, and from the Ozarks into the Ohio Valley. The most favorable corridor for isolated very large hail and significant severe wind gusts is centered on the central High Plains. ...Synopsis... An upper trough will continue moving eastward across Ontario and the Great Lakes today, while an upper high remains centered over the Southeast. Farther west, a separate mid-level shortwave trough will advance east-southeastward from the northern Rockies to the northern/central High Plains through tonight. Multiple convectively augmented mid-level vorticity maxima will move generally east-northeastward across the central Plains into the mid MS and OH Valleys. At the surface, a cold front extends from the OH Valley southwestward to the southern Plains. Weak lee cyclogenesis is forecast to occur across the central High Plains through late this afternoon, and modest low-level moisture return is anticipated to the north of the front and east of a weak surface lee trough across parts of the northern/central Plains. ...Northern/Central Plains... Morning clouds and lingering convection across parts of the central Plains will hamper the development of instability today, especially with eastward extent into NE/KS. Even so, pockets of filtered daytime heating will occur across the northern/central High Plains along and east of the surface lee trough. With steepened mid-level lapse rates present over eastern CO/WY into western SD/NE, a narrow zone of moderate instability is forecast to be in place prior to robust convective initiation this afternoon. Initial development should occur along the length of the lee trough from parts of western NE into eastern CO. A somewhat separate area of convection may also develop from northeastern WY to the Black Hills, as large-scale ascent preceding the mid-level shortwave trough overspreads this region. Modest low-level east-southeasterly flow will quickly veer to westerly at mid/upper levels, with some strengthening and hodograph elongation. Corresponding strong deep-layer shear will support supercells initially, with attendant threat for large hail. Given relatively cool temperatures aloft and the presence of steep mid-level lapse rates, isolated very large hail greater than 2 inches in diameter appears possible. A small zone with favorable overlap of moderate instability, strong deep-layer shear, and sufficient low-level shear remains apparent over parts of the NE Panhandle into northwest NE. This area may have a locally greater threat for a couple of tornadoes with any supercells that can persist late this afternoon into the early evening, assuming the boundary layer does not become too well mixed. Otherwise, upscale growth/clustering appears probable this evening as convective outflows aggregate into the central Plains. Severe/damaging winds should become the main threat as this occurs, with isolated significant gusts up to 75 mph possible if a more consolidated bow/MCS can develop. Confidence in this occurring still remains somewhat low, but the best chance for a more concentrated corridor of severe winds remains across parts of eastern CO into southwest NE and northwest KS this evening. ...Ozarks to the Ohio Valley... A rather moist low-level airmass remains present along/south of the front today, with surface dewpoints generally in the low to mid 70s, and precipitable water values around 1.75-2.2 inches. A fair amount of convective cloud debris is present along/near the front across the mid MS Valley. This will tend to slow diurnal destabilization to some extent across this area. Mid-level lapse rates are also expected to remain poor. Still, moderate to locally strong instability and steepened low-level lapse rates are forecast to develop through peak afternoon heating along/south of the front, which will extend from the Ozarks northeastward into parts of the OH Valley. Low-level winds are expected to remain generally weak, but a modest increase in southwesterly winds at mid levels should foster sufficient deep-layer shear to support some updraft organization. Mainly multicell clusters should develop this afternoon, focused along the front. Some of this activity may produce scattered damaging winds through early evening before eventually weakening. Morning guidance shows a greater concentration of thunderstorms with clustering potential across the Ozarks into the mid MS Valley. ..Gleason/Thornton.. 07/03/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Wed Jul 03 2024 Valid 031630Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS...AND THE OZARKS INTO PORTIONS OF THE OHIO VALLEY... ...SUMMARY... Scattered severe thunderstorms appear possible this afternoon and evening across parts of the northern/central High Plains, and from the Ozarks into the Ohio Valley. The most favorable corridor for isolated very large hail and significant severe wind gusts is centered on the central High Plains. ...Synopsis... An upper trough will continue moving eastward across Ontario and the Great Lakes today, while an upper high remains centered over the Southeast. Farther west, a separate mid-level shortwave trough will advance east-southeastward from the northern Rockies to the northern/central High Plains through tonight. Multiple convectively augmented mid-level vorticity maxima will move generally east-northeastward across the central Plains into the mid MS and OH Valleys. At the surface, a cold front extends from the OH Valley southwestward to the southern Plains. Weak lee cyclogenesis is forecast to occur across the central High Plains through late this afternoon, and modest low-level moisture return is anticipated to the north of the front and east of a weak surface lee trough across parts of the northern/central Plains. ...Northern/Central Plains... Morning clouds and lingering convection across parts of the central Plains will hamper the development of instability today, especially with eastward extent into NE/KS. Even so, pockets of filtered daytime heating will occur across the northern/central High Plains along and east of the surface lee trough. With steepened mid-level lapse rates present over eastern CO/WY into western SD/NE, a narrow zone of moderate instability is forecast to be in place prior to robust convective initiation this afternoon. Initial development should occur along the length of the lee trough from parts of western NE into eastern CO. A somewhat separate area of convection may also develop from northeastern WY to the Black Hills, as large-scale ascent preceding the mid-level shortwave trough overspreads this region. Modest low-level east-southeasterly flow will quickly veer to westerly at mid/upper levels, with some strengthening and hodograph elongation. Corresponding strong deep-layer shear will support supercells initially, with attendant threat for large hail. Given relatively cool temperatures aloft and the presence of steep mid-level lapse rates, isolated very large hail greater than 2 inches in diameter appears possible. A small zone with favorable overlap of moderate instability, strong deep-layer shear, and sufficient low-level shear remains apparent over parts of the NE Panhandle into northwest NE. This area may have a locally greater threat for a couple of tornadoes with any supercells that can persist late this afternoon into the early evening, assuming the boundary layer does not become too well mixed. Otherwise, upscale growth/clustering appears probable this evening as convective outflows aggregate into the central Plains. Severe/damaging winds should become the main threat as this occurs, with isolated significant gusts up to 75 mph possible if a more consolidated bow/MCS can develop. Confidence in this occurring still remains somewhat low, but the best chance for a more concentrated corridor of severe winds remains across parts of eastern CO into southwest NE and northwest KS this evening. ...Ozarks to the Ohio Valley... A rather moist low-level airmass remains present along/south of the front today, with surface dewpoints generally in the low to mid 70s, and precipitable water values around 1.75-2.2 inches. A fair amount of convective cloud debris is present along/near the front across the mid MS Valley. This will tend to slow diurnal destabilization to some extent across this area. Mid-level lapse rates are also expected to remain poor. Still, moderate to locally strong instability and steepened low-level lapse rates are forecast to develop through peak afternoon heating along/south of the front, which will extend from the Ozarks northeastward into parts of the OH Valley. Low-level winds are expected to remain generally weak, but a modest increase in southwesterly winds at mid levels should foster sufficient deep-layer shear to support some updraft organization. Mainly multicell clusters should develop this afternoon, focused along the front. Some of this activity may produce scattered damaging winds through early evening before eventually weakening. Morning guidance shows a greater concentration of thunderstorms with clustering potential across the Ozarks into the mid MS Valley. ..Gleason/Thornton.. 07/03/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Wed Jul 03 2024 Valid 031630Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS...AND THE OZARKS INTO PORTIONS OF THE OHIO VALLEY... ...SUMMARY... Scattered severe thunderstorms appear possible this afternoon and evening across parts of the northern/central High Plains, and from the Ozarks into the Ohio Valley. The most favorable corridor for isolated very large hail and significant severe wind gusts is centered on the central High Plains. ...Synopsis... An upper trough will continue moving eastward across Ontario and the Great Lakes today, while an upper high remains centered over the Southeast. Farther west, a separate mid-level shortwave trough will advance east-southeastward from the northern Rockies to the northern/central High Plains through tonight. Multiple convectively augmented mid-level vorticity maxima will move generally east-northeastward across the central Plains into the mid MS and OH Valleys. At the surface, a cold front extends from the OH Valley southwestward to the southern Plains. Weak lee cyclogenesis is forecast to occur across the central High Plains through late this afternoon, and modest low-level moisture return is anticipated to the north of the front and east of a weak surface lee trough across parts of the northern/central Plains. ...Northern/Central Plains... Morning clouds and lingering convection across parts of the central Plains will hamper the development of instability today, especially with eastward extent into NE/KS. Even so, pockets of filtered daytime heating will occur across the northern/central High Plains along and east of the surface lee trough. With steepened mid-level lapse rates present over eastern CO/WY into western SD/NE, a narrow zone of moderate instability is forecast to be in place prior to robust convective initiation this afternoon. Initial development should occur along the length of the lee trough from parts of western NE into eastern CO. A somewhat separate area of convection may also develop from northeastern WY to the Black Hills, as large-scale ascent preceding the mid-level shortwave trough overspreads this region. Modest low-level east-southeasterly flow will quickly veer to westerly at mid/upper levels, with some strengthening and hodograph elongation. Corresponding strong deep-layer shear will support supercells initially, with attendant threat for large hail. Given relatively cool temperatures aloft and the presence of steep mid-level lapse rates, isolated very large hail greater than 2 inches in diameter appears possible. A small zone with favorable overlap of moderate instability, strong deep-layer shear, and sufficient low-level shear remains apparent over parts of the NE Panhandle into northwest NE. This area may have a locally greater threat for a couple of tornadoes with any supercells that can persist late this afternoon into the early evening, assuming the boundary layer does not become too well mixed. Otherwise, upscale growth/clustering appears probable this evening as convective outflows aggregate into the central Plains. Severe/damaging winds should become the main threat as this occurs, with isolated significant gusts up to 75 mph possible if a more consolidated bow/MCS can develop. Confidence in this occurring still remains somewhat low, but the best chance for a more concentrated corridor of severe winds remains across parts of eastern CO into southwest NE and northwest KS this evening. ...Ozarks to the Ohio Valley... A rather moist low-level airmass remains present along/south of the front today, with surface dewpoints generally in the low to mid 70s, and precipitable water values around 1.75-2.2 inches. A fair amount of convective cloud debris is present along/near the front across the mid MS Valley. This will tend to slow diurnal destabilization to some extent across this area. Mid-level lapse rates are also expected to remain poor. Still, moderate to locally strong instability and steepened low-level lapse rates are forecast to develop through peak afternoon heating along/south of the front, which will extend from the Ozarks northeastward into parts of the OH Valley. Low-level winds are expected to remain generally weak, but a modest increase in southwesterly winds at mid levels should foster sufficient deep-layer shear to support some updraft organization. Mainly multicell clusters should develop this afternoon, focused along the front. Some of this activity may produce scattered damaging winds through early evening before eventually weakening. Morning guidance shows a greater concentration of thunderstorms with clustering potential across the Ozarks into the mid MS Valley. ..Gleason/Thornton.. 07/03/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Wed Jul 03 2024 Valid 031630Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS...AND THE OZARKS INTO PORTIONS OF THE OHIO VALLEY... ...SUMMARY... Scattered severe thunderstorms appear possible this afternoon and evening across parts of the northern/central High Plains, and from the Ozarks into the Ohio Valley. The most favorable corridor for isolated very large hail and significant severe wind gusts is centered on the central High Plains. ...Synopsis... An upper trough will continue moving eastward across Ontario and the Great Lakes today, while an upper high remains centered over the Southeast. Farther west, a separate mid-level shortwave trough will advance east-southeastward from the northern Rockies to the northern/central High Plains through tonight. Multiple convectively augmented mid-level vorticity maxima will move generally east-northeastward across the central Plains into the mid MS and OH Valleys. At the surface, a cold front extends from the OH Valley southwestward to the southern Plains. Weak lee cyclogenesis is forecast to occur across the central High Plains through late this afternoon, and modest low-level moisture return is anticipated to the north of the front and east of a weak surface lee trough across parts of the northern/central Plains. ...Northern/Central Plains... Morning clouds and lingering convection across parts of the central Plains will hamper the development of instability today, especially with eastward extent into NE/KS. Even so, pockets of filtered daytime heating will occur across the northern/central High Plains along and east of the surface lee trough. With steepened mid-level lapse rates present over eastern CO/WY into western SD/NE, a narrow zone of moderate instability is forecast to be in place prior to robust convective initiation this afternoon. Initial development should occur along the length of the lee trough from parts of western NE into eastern CO. A somewhat separate area of convection may also develop from northeastern WY to the Black Hills, as large-scale ascent preceding the mid-level shortwave trough overspreads this region. Modest low-level east-southeasterly flow will quickly veer to westerly at mid/upper levels, with some strengthening and hodograph elongation. Corresponding strong deep-layer shear will support supercells initially, with attendant threat for large hail. Given relatively cool temperatures aloft and the presence of steep mid-level lapse rates, isolated very large hail greater than 2 inches in diameter appears possible. A small zone with favorable overlap of moderate instability, strong deep-layer shear, and sufficient low-level shear remains apparent over parts of the NE Panhandle into northwest NE. This area may have a locally greater threat for a couple of tornadoes with any supercells that can persist late this afternoon into the early evening, assuming the boundary layer does not become too well mixed. Otherwise, upscale growth/clustering appears probable this evening as convective outflows aggregate into the central Plains. Severe/damaging winds should become the main threat as this occurs, with isolated significant gusts up to 75 mph possible if a more consolidated bow/MCS can develop. Confidence in this occurring still remains somewhat low, but the best chance for a more concentrated corridor of severe winds remains across parts of eastern CO into southwest NE and northwest KS this evening. ...Ozarks to the Ohio Valley... A rather moist low-level airmass remains present along/south of the front today, with surface dewpoints generally in the low to mid 70s, and precipitable water values around 1.75-2.2 inches. A fair amount of convective cloud debris is present along/near the front across the mid MS Valley. This will tend to slow diurnal destabilization to some extent across this area. Mid-level lapse rates are also expected to remain poor. Still, moderate to locally strong instability and steepened low-level lapse rates are forecast to develop through peak afternoon heating along/south of the front, which will extend from the Ozarks northeastward into parts of the OH Valley. Low-level winds are expected to remain generally weak, but a modest increase in southwesterly winds at mid levels should foster sufficient deep-layer shear to support some updraft organization. Mainly multicell clusters should develop this afternoon, focused along the front. Some of this activity may produce scattered damaging winds through early evening before eventually weakening. Morning guidance shows a greater concentration of thunderstorms with clustering potential across the Ozarks into the mid MS Valley. ..Gleason/Thornton.. 07/03/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Wed Jul 03 2024 Valid 031630Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS...AND THE OZARKS INTO PORTIONS OF THE OHIO VALLEY... ...SUMMARY... Scattered severe thunderstorms appear possible this afternoon and evening across parts of the northern/central High Plains, and from the Ozarks into the Ohio Valley. The most favorable corridor for isolated very large hail and significant severe wind gusts is centered on the central High Plains. ...Synopsis... An upper trough will continue moving eastward across Ontario and the Great Lakes today, while an upper high remains centered over the Southeast. Farther west, a separate mid-level shortwave trough will advance east-southeastward from the northern Rockies to the northern/central High Plains through tonight. Multiple convectively augmented mid-level vorticity maxima will move generally east-northeastward across the central Plains into the mid MS and OH Valleys. At the surface, a cold front extends from the OH Valley southwestward to the southern Plains. Weak lee cyclogenesis is forecast to occur across the central High Plains through late this afternoon, and modest low-level moisture return is anticipated to the north of the front and east of a weak surface lee trough across parts of the northern/central Plains. ...Northern/Central Plains... Morning clouds and lingering convection across parts of the central Plains will hamper the development of instability today, especially with eastward extent into NE/KS. Even so, pockets of filtered daytime heating will occur across the northern/central High Plains along and east of the surface lee trough. With steepened mid-level lapse rates present over eastern CO/WY into western SD/NE, a narrow zone of moderate instability is forecast to be in place prior to robust convective initiation this afternoon. Initial development should occur along the length of the lee trough from parts of western NE into eastern CO. A somewhat separate area of convection may also develop from northeastern WY to the Black Hills, as large-scale ascent preceding the mid-level shortwave trough overspreads this region. Modest low-level east-southeasterly flow will quickly veer to westerly at mid/upper levels, with some strengthening and hodograph elongation. Corresponding strong deep-layer shear will support supercells initially, with attendant threat for large hail. Given relatively cool temperatures aloft and the presence of steep mid-level lapse rates, isolated very large hail greater than 2 inches in diameter appears possible. A small zone with favorable overlap of moderate instability, strong deep-layer shear, and sufficient low-level shear remains apparent over parts of the NE Panhandle into northwest NE. This area may have a locally greater threat for a couple of tornadoes with any supercells that can persist late this afternoon into the early evening, assuming the boundary layer does not become too well mixed. Otherwise, upscale growth/clustering appears probable this evening as convective outflows aggregate into the central Plains. Severe/damaging winds should become the main threat as this occurs, with isolated significant gusts up to 75 mph possible if a more consolidated bow/MCS can develop. Confidence in this occurring still remains somewhat low, but the best chance for a more concentrated corridor of severe winds remains across parts of eastern CO into southwest NE and northwest KS this evening. ...Ozarks to the Ohio Valley... A rather moist low-level airmass remains present along/south of the front today, with surface dewpoints generally in the low to mid 70s, and precipitable water values around 1.75-2.2 inches. A fair amount of convective cloud debris is present along/near the front across the mid MS Valley. This will tend to slow diurnal destabilization to some extent across this area. Mid-level lapse rates are also expected to remain poor. Still, moderate to locally strong instability and steepened low-level lapse rates are forecast to develop through peak afternoon heating along/south of the front, which will extend from the Ozarks northeastward into parts of the OH Valley. Low-level winds are expected to remain generally weak, but a modest increase in southwesterly winds at mid levels should foster sufficient deep-layer shear to support some updraft organization. Mainly multicell clusters should develop this afternoon, focused along the front. Some of this activity may produce scattered damaging winds through early evening before eventually weakening. Morning guidance shows a greater concentration of thunderstorms with clustering potential across the Ozarks into the mid MS Valley. ..Gleason/Thornton.. 07/03/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Wed Jul 03 2024 Valid 031630Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS...AND THE OZARKS INTO PORTIONS OF THE OHIO VALLEY... ...SUMMARY... Scattered severe thunderstorms appear possible this afternoon and evening across parts of the northern/central High Plains, and from the Ozarks into the Ohio Valley. The most favorable corridor for isolated very large hail and significant severe wind gusts is centered on the central High Plains. ...Synopsis... An upper trough will continue moving eastward across Ontario and the Great Lakes today, while an upper high remains centered over the Southeast. Farther west, a separate mid-level shortwave trough will advance east-southeastward from the northern Rockies to the northern/central High Plains through tonight. Multiple convectively augmented mid-level vorticity maxima will move generally east-northeastward across the central Plains into the mid MS and OH Valleys. At the surface, a cold front extends from the OH Valley southwestward to the southern Plains. Weak lee cyclogenesis is forecast to occur across the central High Plains through late this afternoon, and modest low-level moisture return is anticipated to the north of the front and east of a weak surface lee trough across parts of the northern/central Plains. ...Northern/Central Plains... Morning clouds and lingering convection across parts of the central Plains will hamper the development of instability today, especially with eastward extent into NE/KS. Even so, pockets of filtered daytime heating will occur across the northern/central High Plains along and east of the surface lee trough. With steepened mid-level lapse rates present over eastern CO/WY into western SD/NE, a narrow zone of moderate instability is forecast to be in place prior to robust convective initiation this afternoon. Initial development should occur along the length of the lee trough from parts of western NE into eastern CO. A somewhat separate area of convection may also develop from northeastern WY to the Black Hills, as large-scale ascent preceding the mid-level shortwave trough overspreads this region. Modest low-level east-southeasterly flow will quickly veer to westerly at mid/upper levels, with some strengthening and hodograph elongation. Corresponding strong deep-layer shear will support supercells initially, with attendant threat for large hail. Given relatively cool temperatures aloft and the presence of steep mid-level lapse rates, isolated very large hail greater than 2 inches in diameter appears possible. A small zone with favorable overlap of moderate instability, strong deep-layer shear, and sufficient low-level shear remains apparent over parts of the NE Panhandle into northwest NE. This area may have a locally greater threat for a couple of tornadoes with any supercells that can persist late this afternoon into the early evening, assuming the boundary layer does not become too well mixed. Otherwise, upscale growth/clustering appears probable this evening as convective outflows aggregate into the central Plains. Severe/damaging winds should become the main threat as this occurs, with isolated significant gusts up to 75 mph possible if a more consolidated bow/MCS can develop. Confidence in this occurring still remains somewhat low, but the best chance for a more concentrated corridor of severe winds remains across parts of eastern CO into southwest NE and northwest KS this evening. ...Ozarks to the Ohio Valley... A rather moist low-level airmass remains present along/south of the front today, with surface dewpoints generally in the low to mid 70s, and precipitable water values around 1.75-2.2 inches. A fair amount of convective cloud debris is present along/near the front across the mid MS Valley. This will tend to slow diurnal destabilization to some extent across this area. Mid-level lapse rates are also expected to remain poor. Still, moderate to locally strong instability and steepened low-level lapse rates are forecast to develop through peak afternoon heating along/south of the front, which will extend from the Ozarks northeastward into parts of the OH Valley. Low-level winds are expected to remain generally weak, but a modest increase in southwesterly winds at mid levels should foster sufficient deep-layer shear to support some updraft organization. Mainly multicell clusters should develop this afternoon, focused along the front. Some of this activity may produce scattered damaging winds through early evening before eventually weakening. Morning guidance shows a greater concentration of thunderstorms with clustering potential across the Ozarks into the mid MS Valley. ..Gleason/Thornton.. 07/03/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Wed Jul 03 2024 Valid 031630Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS...AND THE OZARKS INTO PORTIONS OF THE OHIO VALLEY... ...SUMMARY... Scattered severe thunderstorms appear possible this afternoon and evening across parts of the northern/central High Plains, and from the Ozarks into the Ohio Valley. The most favorable corridor for isolated very large hail and significant severe wind gusts is centered on the central High Plains. ...Synopsis... An upper trough will continue moving eastward across Ontario and the Great Lakes today, while an upper high remains centered over the Southeast. Farther west, a separate mid-level shortwave trough will advance east-southeastward from the northern Rockies to the northern/central High Plains through tonight. Multiple convectively augmented mid-level vorticity maxima will move generally east-northeastward across the central Plains into the mid MS and OH Valleys. At the surface, a cold front extends from the OH Valley southwestward to the southern Plains. Weak lee cyclogenesis is forecast to occur across the central High Plains through late this afternoon, and modest low-level moisture return is anticipated to the north of the front and east of a weak surface lee trough across parts of the northern/central Plains. ...Northern/Central Plains... Morning clouds and lingering convection across parts of the central Plains will hamper the development of instability today, especially with eastward extent into NE/KS. Even so, pockets of filtered daytime heating will occur across the northern/central High Plains along and east of the surface lee trough. With steepened mid-level lapse rates present over eastern CO/WY into western SD/NE, a narrow zone of moderate instability is forecast to be in place prior to robust convective initiation this afternoon. Initial development should occur along the length of the lee trough from parts of western NE into eastern CO. A somewhat separate area of convection may also develop from northeastern WY to the Black Hills, as large-scale ascent preceding the mid-level shortwave trough overspreads this region. Modest low-level east-southeasterly flow will quickly veer to westerly at mid/upper levels, with some strengthening and hodograph elongation. Corresponding strong deep-layer shear will support supercells initially, with attendant threat for large hail. Given relatively cool temperatures aloft and the presence of steep mid-level lapse rates, isolated very large hail greater than 2 inches in diameter appears possible. A small zone with favorable overlap of moderate instability, strong deep-layer shear, and sufficient low-level shear remains apparent over parts of the NE Panhandle into northwest NE. This area may have a locally greater threat for a couple of tornadoes with any supercells that can persist late this afternoon into the early evening, assuming the boundary layer does not become too well mixed. Otherwise, upscale growth/clustering appears probable this evening as convective outflows aggregate into the central Plains. Severe/damaging winds should become the main threat as this occurs, with isolated significant gusts up to 75 mph possible if a more consolidated bow/MCS can develop. Confidence in this occurring still remains somewhat low, but the best chance for a more concentrated corridor of severe winds remains across parts of eastern CO into southwest NE and northwest KS this evening. ...Ozarks to the Ohio Valley... A rather moist low-level airmass remains present along/south of the front today, with surface dewpoints generally in the low to mid 70s, and precipitable water values around 1.75-2.2 inches. A fair amount of convective cloud debris is present along/near the front across the mid MS Valley. This will tend to slow diurnal destabilization to some extent across this area. Mid-level lapse rates are also expected to remain poor. Still, moderate to locally strong instability and steepened low-level lapse rates are forecast to develop through peak afternoon heating along/south of the front, which will extend from the Ozarks northeastward into parts of the OH Valley. Low-level winds are expected to remain generally weak, but a modest increase in southwesterly winds at mid levels should foster sufficient deep-layer shear to support some updraft organization. Mainly multicell clusters should develop this afternoon, focused along the front. Some of this activity may produce scattered damaging winds through early evening before eventually weakening. Morning guidance shows a greater concentration of thunderstorms with clustering potential across the Ozarks into the mid MS Valley. ..Gleason/Thornton.. 07/03/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Wed Jul 03 2024 Valid 031630Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS...AND THE OZARKS INTO PORTIONS OF THE OHIO VALLEY... ...SUMMARY... Scattered severe thunderstorms appear possible this afternoon and evening across parts of the northern/central High Plains, and from the Ozarks into the Ohio Valley. The most favorable corridor for isolated very large hail and significant severe wind gusts is centered on the central High Plains. ...Synopsis... An upper trough will continue moving eastward across Ontario and the Great Lakes today, while an upper high remains centered over the Southeast. Farther west, a separate mid-level shortwave trough will advance east-southeastward from the northern Rockies to the northern/central High Plains through tonight. Multiple convectively augmented mid-level vorticity maxima will move generally east-northeastward across the central Plains into the mid MS and OH Valleys. At the surface, a cold front extends from the OH Valley southwestward to the southern Plains. Weak lee cyclogenesis is forecast to occur across the central High Plains through late this afternoon, and modest low-level moisture return is anticipated to the north of the front and east of a weak surface lee trough across parts of the northern/central Plains. ...Northern/Central Plains... Morning clouds and lingering convection across parts of the central Plains will hamper the development of instability today, especially with eastward extent into NE/KS. Even so, pockets of filtered daytime heating will occur across the northern/central High Plains along and east of the surface lee trough. With steepened mid-level lapse rates present over eastern CO/WY into western SD/NE, a narrow zone of moderate instability is forecast to be in place prior to robust convective initiation this afternoon. Initial development should occur along the length of the lee trough from parts of western NE into eastern CO. A somewhat separate area of convection may also develop from northeastern WY to the Black Hills, as large-scale ascent preceding the mid-level shortwave trough overspreads this region. Modest low-level east-southeasterly flow will quickly veer to westerly at mid/upper levels, with some strengthening and hodograph elongation. Corresponding strong deep-layer shear will support supercells initially, with attendant threat for large hail. Given relatively cool temperatures aloft and the presence of steep mid-level lapse rates, isolated very large hail greater than 2 inches in diameter appears possible. A small zone with favorable overlap of moderate instability, strong deep-layer shear, and sufficient low-level shear remains apparent over parts of the NE Panhandle into northwest NE. This area may have a locally greater threat for a couple of tornadoes with any supercells that can persist late this afternoon into the early evening, assuming the boundary layer does not become too well mixed. Otherwise, upscale growth/clustering appears probable this evening as convective outflows aggregate into the central Plains. Severe/damaging winds should become the main threat as this occurs, with isolated significant gusts up to 75 mph possible if a more consolidated bow/MCS can develop. Confidence in this occurring still remains somewhat low, but the best chance for a more concentrated corridor of severe winds remains across parts of eastern CO into southwest NE and northwest KS this evening. ...Ozarks to the Ohio Valley... A rather moist low-level airmass remains present along/south of the front today, with surface dewpoints generally in the low to mid 70s, and precipitable water values around 1.75-2.2 inches. A fair amount of convective cloud debris is present along/near the front across the mid MS Valley. This will tend to slow diurnal destabilization to some extent across this area. Mid-level lapse rates are also expected to remain poor. Still, moderate to locally strong instability and steepened low-level lapse rates are forecast to develop through peak afternoon heating along/south of the front, which will extend from the Ozarks northeastward into parts of the OH Valley. Low-level winds are expected to remain generally weak, but a modest increase in southwesterly winds at mid levels should foster sufficient deep-layer shear to support some updraft organization. Mainly multicell clusters should develop this afternoon, focused along the front. Some of this activity may produce scattered damaging winds through early evening before eventually weakening. Morning guidance shows a greater concentration of thunderstorms with clustering potential across the Ozarks into the mid MS Valley. ..Gleason/Thornton.. 07/03/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Wed Jul 03 2024 Valid 031630Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS...AND THE OZARKS INTO PORTIONS OF THE OHIO VALLEY... ...SUMMARY... Scattered severe thunderstorms appear possible this afternoon and evening across parts of the northern/central High Plains, and from the Ozarks into the Ohio Valley. The most favorable corridor for isolated very large hail and significant severe wind gusts is centered on the central High Plains. ...Synopsis... An upper trough will continue moving eastward across Ontario and the Great Lakes today, while an upper high remains centered over the Southeast. Farther west, a separate mid-level shortwave trough will advance east-southeastward from the northern Rockies to the northern/central High Plains through tonight. Multiple convectively augmented mid-level vorticity maxima will move generally east-northeastward across the central Plains into the mid MS and OH Valleys. At the surface, a cold front extends from the OH Valley southwestward to the southern Plains. Weak lee cyclogenesis is forecast to occur across the central High Plains through late this afternoon, and modest low-level moisture return is anticipated to the north of the front and east of a weak surface lee trough across parts of the northern/central Plains. ...Northern/Central Plains... Morning clouds and lingering convection across parts of the central Plains will hamper the development of instability today, especially with eastward extent into NE/KS. Even so, pockets of filtered daytime heating will occur across the northern/central High Plains along and east of the surface lee trough. With steepened mid-level lapse rates present over eastern CO/WY into western SD/NE, a narrow zone of moderate instability is forecast to be in place prior to robust convective initiation this afternoon. Initial development should occur along the length of the lee trough from parts of western NE into eastern CO. A somewhat separate area of convection may also develop from northeastern WY to the Black Hills, as large-scale ascent preceding the mid-level shortwave trough overspreads this region. Modest low-level east-southeasterly flow will quickly veer to westerly at mid/upper levels, with some strengthening and hodograph elongation. Corresponding strong deep-layer shear will support supercells initially, with attendant threat for large hail. Given relatively cool temperatures aloft and the presence of steep mid-level lapse rates, isolated very large hail greater than 2 inches in diameter appears possible. A small zone with favorable overlap of moderate instability, strong deep-layer shear, and sufficient low-level shear remains apparent over parts of the NE Panhandle into northwest NE. This area may have a locally greater threat for a couple of tornadoes with any supercells that can persist late this afternoon into the early evening, assuming the boundary layer does not become too well mixed. Otherwise, upscale growth/clustering appears probable this evening as convective outflows aggregate into the central Plains. Severe/damaging winds should become the main threat as this occurs, with isolated significant gusts up to 75 mph possible if a more consolidated bow/MCS can develop. Confidence in this occurring still remains somewhat low, but the best chance for a more concentrated corridor of severe winds remains across parts of eastern CO into southwest NE and northwest KS this evening. ...Ozarks to the Ohio Valley... A rather moist low-level airmass remains present along/south of the front today, with surface dewpoints generally in the low to mid 70s, and precipitable water values around 1.75-2.2 inches. A fair amount of convective cloud debris is present along/near the front across the mid MS Valley. This will tend to slow diurnal destabilization to some extent across this area. Mid-level lapse rates are also expected to remain poor. Still, moderate to locally strong instability and steepened low-level lapse rates are forecast to develop through peak afternoon heating along/south of the front, which will extend from the Ozarks northeastward into parts of the OH Valley. Low-level winds are expected to remain generally weak, but a modest increase in southwesterly winds at mid levels should foster sufficient deep-layer shear to support some updraft organization. Mainly multicell clusters should develop this afternoon, focused along the front. Some of this activity may produce scattered damaging winds through early evening before eventually weakening. Morning guidance shows a greater concentration of thunderstorms with clustering potential across the Ozarks into the mid MS Valley. ..Gleason/Thornton.. 07/03/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Wed Jul 03 2024 Valid 031630Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS...AND THE OZARKS INTO PORTIONS OF THE OHIO VALLEY... ...SUMMARY... Scattered severe thunderstorms appear possible this afternoon and evening across parts of the northern/central High Plains, and from the Ozarks into the Ohio Valley. The most favorable corridor for isolated very large hail and significant severe wind gusts is centered on the central High Plains. ...Synopsis... An upper trough will continue moving eastward across Ontario and the Great Lakes today, while an upper high remains centered over the Southeast. Farther west, a separate mid-level shortwave trough will advance east-southeastward from the northern Rockies to the northern/central High Plains through tonight. Multiple convectively augmented mid-level vorticity maxima will move generally east-northeastward across the central Plains into the mid MS and OH Valleys. At the surface, a cold front extends from the OH Valley southwestward to the southern Plains. Weak lee cyclogenesis is forecast to occur across the central High Plains through late this afternoon, and modest low-level moisture return is anticipated to the north of the front and east of a weak surface lee trough across parts of the northern/central Plains. ...Northern/Central Plains... Morning clouds and lingering convection across parts of the central Plains will hamper the development of instability today, especially with eastward extent into NE/KS. Even so, pockets of filtered daytime heating will occur across the northern/central High Plains along and east of the surface lee trough. With steepened mid-level lapse rates present over eastern CO/WY into western SD/NE, a narrow zone of moderate instability is forecast to be in place prior to robust convective initiation this afternoon. Initial development should occur along the length of the lee trough from parts of western NE into eastern CO. A somewhat separate area of convection may also develop from northeastern WY to the Black Hills, as large-scale ascent preceding the mid-level shortwave trough overspreads this region. Modest low-level east-southeasterly flow will quickly veer to westerly at mid/upper levels, with some strengthening and hodograph elongation. Corresponding strong deep-layer shear will support supercells initially, with attendant threat for large hail. Given relatively cool temperatures aloft and the presence of steep mid-level lapse rates, isolated very large hail greater than 2 inches in diameter appears possible. A small zone with favorable overlap of moderate instability, strong deep-layer shear, and sufficient low-level shear remains apparent over parts of the NE Panhandle into northwest NE. This area may have a locally greater threat for a couple of tornadoes with any supercells that can persist late this afternoon into the early evening, assuming the boundary layer does not become too well mixed. Otherwise, upscale growth/clustering appears probable this evening as convective outflows aggregate into the central Plains. Severe/damaging winds should become the main threat as this occurs, with isolated significant gusts up to 75 mph possible if a more consolidated bow/MCS can develop. Confidence in this occurring still remains somewhat low, but the best chance for a more concentrated corridor of severe winds remains across parts of eastern CO into southwest NE and northwest KS this evening. ...Ozarks to the Ohio Valley... A rather moist low-level airmass remains present along/south of the front today, with surface dewpoints generally in the low to mid 70s, and precipitable water values around 1.75-2.2 inches. A fair amount of convective cloud debris is present along/near the front across the mid MS Valley. This will tend to slow diurnal destabilization to some extent across this area. Mid-level lapse rates are also expected to remain poor. Still, moderate to locally strong instability and steepened low-level lapse rates are forecast to develop through peak afternoon heating along/south of the front, which will extend from the Ozarks northeastward into parts of the OH Valley. Low-level winds are expected to remain generally weak, but a modest increase in southwesterly winds at mid levels should foster sufficient deep-layer shear to support some updraft organization. Mainly multicell clusters should develop this afternoon, focused along the front. Some of this activity may produce scattered damaging winds through early evening before eventually weakening. Morning guidance shows a greater concentration of thunderstorms with clustering potential across the Ozarks into the mid MS Valley. ..Gleason/Thornton.. 07/03/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Wed Jul 03 2024 Valid 031630Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS...AND THE OZARKS INTO PORTIONS OF THE OHIO VALLEY... ...SUMMARY... Scattered severe thunderstorms appear possible this afternoon and evening across parts of the northern/central High Plains, and from the Ozarks into the Ohio Valley. The most favorable corridor for isolated very large hail and significant severe wind gusts is centered on the central High Plains. ...Synopsis... An upper trough will continue moving eastward across Ontario and the Great Lakes today, while an upper high remains centered over the Southeast. Farther west, a separate mid-level shortwave trough will advance east-southeastward from the northern Rockies to the northern/central High Plains through tonight. Multiple convectively augmented mid-level vorticity maxima will move generally east-northeastward across the central Plains into the mid MS and OH Valleys. At the surface, a cold front extends from the OH Valley southwestward to the southern Plains. Weak lee cyclogenesis is forecast to occur across the central High Plains through late this afternoon, and modest low-level moisture return is anticipated to the north of the front and east of a weak surface lee trough across parts of the northern/central Plains. ...Northern/Central Plains... Morning clouds and lingering convection across parts of the central Plains will hamper the development of instability today, especially with eastward extent into NE/KS. Even so, pockets of filtered daytime heating will occur across the northern/central High Plains along and east of the surface lee trough. With steepened mid-level lapse rates present over eastern CO/WY into western SD/NE, a narrow zone of moderate instability is forecast to be in place prior to robust convective initiation this afternoon. Initial development should occur along the length of the lee trough from parts of western NE into eastern CO. A somewhat separate area of convection may also develop from northeastern WY to the Black Hills, as large-scale ascent preceding the mid-level shortwave trough overspreads this region. Modest low-level east-southeasterly flow will quickly veer to westerly at mid/upper levels, with some strengthening and hodograph elongation. Corresponding strong deep-layer shear will support supercells initially, with attendant threat for large hail. Given relatively cool temperatures aloft and the presence of steep mid-level lapse rates, isolated very large hail greater than 2 inches in diameter appears possible. A small zone with favorable overlap of moderate instability, strong deep-layer shear, and sufficient low-level shear remains apparent over parts of the NE Panhandle into northwest NE. This area may have a locally greater threat for a couple of tornadoes with any supercells that can persist late this afternoon into the early evening, assuming the boundary layer does not become too well mixed. Otherwise, upscale growth/clustering appears probable this evening as convective outflows aggregate into the central Plains. Severe/damaging winds should become the main threat as this occurs, with isolated significant gusts up to 75 mph possible if a more consolidated bow/MCS can develop. Confidence in this occurring still remains somewhat low, but the best chance for a more concentrated corridor of severe winds remains across parts of eastern CO into southwest NE and northwest KS this evening. ...Ozarks to the Ohio Valley... A rather moist low-level airmass remains present along/south of the front today, with surface dewpoints generally in the low to mid 70s, and precipitable water values around 1.75-2.2 inches. A fair amount of convective cloud debris is present along/near the front across the mid MS Valley. This will tend to slow diurnal destabilization to some extent across this area. Mid-level lapse rates are also expected to remain poor. Still, moderate to locally strong instability and steepened low-level lapse rates are forecast to develop through peak afternoon heating along/south of the front, which will extend from the Ozarks northeastward into parts of the OH Valley. Low-level winds are expected to remain generally weak, but a modest increase in southwesterly winds at mid levels should foster sufficient deep-layer shear to support some updraft organization. Mainly multicell clusters should develop this afternoon, focused along the front. Some of this activity may produce scattered damaging winds through early evening before eventually weakening. Morning guidance shows a greater concentration of thunderstorms with clustering potential across the Ozarks into the mid MS Valley. ..Gleason/Thornton.. 07/03/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Wed Jul 03 2024 Valid 031630Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS...AND THE OZARKS INTO PORTIONS OF THE OHIO VALLEY... ...SUMMARY... Scattered severe thunderstorms appear possible this afternoon and evening across parts of the northern/central High Plains, and from the Ozarks into the Ohio Valley. The most favorable corridor for isolated very large hail and significant severe wind gusts is centered on the central High Plains. ...Synopsis... An upper trough will continue moving eastward across Ontario and the Great Lakes today, while an upper high remains centered over the Southeast. Farther west, a separate mid-level shortwave trough will advance east-southeastward from the northern Rockies to the northern/central High Plains through tonight. Multiple convectively augmented mid-level vorticity maxima will move generally east-northeastward across the central Plains into the mid MS and OH Valleys. At the surface, a cold front extends from the OH Valley southwestward to the southern Plains. Weak lee cyclogenesis is forecast to occur across the central High Plains through late this afternoon, and modest low-level moisture return is anticipated to the north of the front and east of a weak surface lee trough across parts of the northern/central Plains. ...Northern/Central Plains... Morning clouds and lingering convection across parts of the central Plains will hamper the development of instability today, especially with eastward extent into NE/KS. Even so, pockets of filtered daytime heating will occur across the northern/central High Plains along and east of the surface lee trough. With steepened mid-level lapse rates present over eastern CO/WY into western SD/NE, a narrow zone of moderate instability is forecast to be in place prior to robust convective initiation this afternoon. Initial development should occur along the length of the lee trough from parts of western NE into eastern CO. A somewhat separate area of convection may also develop from northeastern WY to the Black Hills, as large-scale ascent preceding the mid-level shortwave trough overspreads this region. Modest low-level east-southeasterly flow will quickly veer to westerly at mid/upper levels, with some strengthening and hodograph elongation. Corresponding strong deep-layer shear will support supercells initially, with attendant threat for large hail. Given relatively cool temperatures aloft and the presence of steep mid-level lapse rates, isolated very large hail greater than 2 inches in diameter appears possible. A small zone with favorable overlap of moderate instability, strong deep-layer shear, and sufficient low-level shear remains apparent over parts of the NE Panhandle into northwest NE. This area may have a locally greater threat for a couple of tornadoes with any supercells that can persist late this afternoon into the early evening, assuming the boundary layer does not become too well mixed. Otherwise, upscale growth/clustering appears probable this evening as convective outflows aggregate into the central Plains. Severe/damaging winds should become the main threat as this occurs, with isolated significant gusts up to 75 mph possible if a more consolidated bow/MCS can develop. Confidence in this occurring still remains somewhat low, but the best chance for a more concentrated corridor of severe winds remains across parts of eastern CO into southwest NE and northwest KS this evening. ...Ozarks to the Ohio Valley... A rather moist low-level airmass remains present along/south of the front today, with surface dewpoints generally in the low to mid 70s, and precipitable water values around 1.75-2.2 inches. A fair amount of convective cloud debris is present along/near the front across the mid MS Valley. This will tend to slow diurnal destabilization to some extent across this area. Mid-level lapse rates are also expected to remain poor. Still, moderate to locally strong instability and steepened low-level lapse rates are forecast to develop through peak afternoon heating along/south of the front, which will extend from the Ozarks northeastward into parts of the OH Valley. Low-level winds are expected to remain generally weak, but a modest increase in southwesterly winds at mid levels should foster sufficient deep-layer shear to support some updraft organization. Mainly multicell clusters should develop this afternoon, focused along the front. Some of this activity may produce scattered damaging winds through early evening before eventually weakening. Morning guidance shows a greater concentration of thunderstorms with clustering potential across the Ozarks into the mid MS Valley. ..Gleason/Thornton.. 07/03/2024 Read more

No Mesoscale Discussions are in effect as of Wed Jul 3 16:33:02 UTC 2024.

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0753 AM CDT Wed Jul 03 2024 Valid 031300Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF THE CENTRAL/NORTHERN HIGH PLAINS... ...SUMMARY... A threat for all severe hazards is possible this afternoon into evening over portions of the central/northern High Plains. Damaging to severe gusts may occur near a separate front, mainly from the Ozarks to Ohio. ...Synopsis... In mid/upper levels, broadly cyclonic flow will continue over much of the northern CONUS from the Pacific Northwest to the Upper Great Lakes, with numerous embedded vorticity maxima and shortwaves of varying amplitudes. Of those, the most important for this outlook will be a shortwave trough now apparent in moisture-channel imagery over northern Rockies. This feature should dig southeastward to southwestern ND, southeastern MT, northwestern WY and southeastern ID by 00Z. By the end of the period (12Z), the trough should extend diagonal across SD, then to southeastern WY and northwestern CO. Subtropical ridging will persist over the Gulf Coast States and portions of southern CA/AZ, with a height weakness in between, over northwestern MX and NM. At the surface, 11Z analysis showed a cold front across Lake Michigan, northwestern IL, central MO, and southeastern KS, becoming quasistationary across northwestern OK and the TX Panhandle to northeastern NM. By 00Z, the front should move to Lake Huron, northwestern OH, southern IN, southern MO, while drifting southward again to northeastern and west-central OK and the southern Panhandle/northern South Plains region of TX. By 12Z, the front should extend over western parts of NY/PA, eastern/southern KY, and north-central AR, becoming a warm front over north-central/ northwestern OK. Cyclogenesis is forecast late this afternoon through this evening along a lee trough over east-central CO, with a cold front developing from the NE Sandhills into northeastern/ central CO by 06Z. By 12Z, the low should migrate to central NE, with warm front over southern IA, and cold front southwestward across western KS to northeastern NM. ...Central/northern High Plains and vicinity... Isolated to scattered thunderstorms are expected to develop this afternoon -- initially over higher terrain near the Palmer and Cheyenne Ridges and near lee trough, increasing in coverage while moving eastward to southeastward over the High Plains. Large hail (some 2+ inches in diameter) and damaging wind (some gusts over 70 mph) are expected over the north-central High Plains, and a couple tornadoes also are possible, mainly in and near western NE where some overlap of favorable moisture and low-level shear is expected. As the mid/upper trough approaches, expect a favorable strengthening of large-scale lift, winds aloft, deep shear, and mass response leading to northward moisture advection/transport, to the north of the southern frontal zone. Optimal moisture return may be precluded by effects of ongoing clouds/precip to reinforce the baroclinic zone over the southern Plains; however, boundary-layer moisture should be sufficient to support development as heating of higher terrain preferentially erodes MLCINH. Steep low/middle-level lapse rates will contribute to development of 1000-2500 J/kg MLCAPE in a corridor from eastern CO and northwestern KS to southwestern SD, decreasing from there westward toward the Bighorns and southward into less-unstable conditions of the Panhandles and northeastern NM. Veering of winds with height east of the lee trough will contribute to favorable vertical shear for supercells and organized/upscale- coalescing multicells, the latter being most commonly progged over parts of eastern CO and northwestern KS (where wind probabilities are relatively maximized). Low-level hodographs should be relatively maximized in size over western NE, and rather elongated over a broader swath of the central High Plains, supporting large to significant hail production. ...Lower Ohio Valley region... Widely scattered to scattered, multicell thunderstorms are expected to develop this afternoon and focus mainly near the front and prefrontal outflow/differential-heating boundaries, from northern OK to the Lower Great Lakes. The greatest concentration of convection is still expected over the area from the Ozarks to central OH from late afternoon into early evening. Forecast soundings suggest that diurnal heating and rich boundary-layer moisture, represented by upper 60s to lower 70s surface dewpoints, will offset modest mid/upper-level lapse rates enough to support peak/preconvective MLCAPE in the 2500-3500 J/kg range over the Ozarks, to 1000-2000 J/kg in OH. Conversely, low-level and deep-layer shear will be fairly weak overall, and decreasing with southwestward extent. Damaging to severe gusts will be the main concern. A few short- lived convective clusters are possible, with locally maximized potential for severe gusts. ..Edwards/Kerr.. 07/03/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0753 AM CDT Wed Jul 03 2024 Valid 031300Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF THE CENTRAL/NORTHERN HIGH PLAINS... ...SUMMARY... A threat for all severe hazards is possible this afternoon into evening over portions of the central/northern High Plains. Damaging to severe gusts may occur near a separate front, mainly from the Ozarks to Ohio. ...Synopsis... In mid/upper levels, broadly cyclonic flow will continue over much of the northern CONUS from the Pacific Northwest to the Upper Great Lakes, with numerous embedded vorticity maxima and shortwaves of varying amplitudes. Of those, the most important for this outlook will be a shortwave trough now apparent in moisture-channel imagery over northern Rockies. This feature should dig southeastward to southwestern ND, southeastern MT, northwestern WY and southeastern ID by 00Z. By the end of the period (12Z), the trough should extend diagonal across SD, then to southeastern WY and northwestern CO. Subtropical ridging will persist over the Gulf Coast States and portions of southern CA/AZ, with a height weakness in between, over northwestern MX and NM. At the surface, 11Z analysis showed a cold front across Lake Michigan, northwestern IL, central MO, and southeastern KS, becoming quasistationary across northwestern OK and the TX Panhandle to northeastern NM. By 00Z, the front should move to Lake Huron, northwestern OH, southern IN, southern MO, while drifting southward again to northeastern and west-central OK and the southern Panhandle/northern South Plains region of TX. By 12Z, the front should extend over western parts of NY/PA, eastern/southern KY, and north-central AR, becoming a warm front over north-central/ northwestern OK. Cyclogenesis is forecast late this afternoon through this evening along a lee trough over east-central CO, with a cold front developing from the NE Sandhills into northeastern/ central CO by 06Z. By 12Z, the low should migrate to central NE, with warm front over southern IA, and cold front southwestward across western KS to northeastern NM. ...Central/northern High Plains and vicinity... Isolated to scattered thunderstorms are expected to develop this afternoon -- initially over higher terrain near the Palmer and Cheyenne Ridges and near lee trough, increasing in coverage while moving eastward to southeastward over the High Plains. Large hail (some 2+ inches in diameter) and damaging wind (some gusts over 70 mph) are expected over the north-central High Plains, and a couple tornadoes also are possible, mainly in and near western NE where some overlap of favorable moisture and low-level shear is expected. As the mid/upper trough approaches, expect a favorable strengthening of large-scale lift, winds aloft, deep shear, and mass response leading to northward moisture advection/transport, to the north of the southern frontal zone. Optimal moisture return may be precluded by effects of ongoing clouds/precip to reinforce the baroclinic zone over the southern Plains; however, boundary-layer moisture should be sufficient to support development as heating of higher terrain preferentially erodes MLCINH. Steep low/middle-level lapse rates will contribute to development of 1000-2500 J/kg MLCAPE in a corridor from eastern CO and northwestern KS to southwestern SD, decreasing from there westward toward the Bighorns and southward into less-unstable conditions of the Panhandles and northeastern NM. Veering of winds with height east of the lee trough will contribute to favorable vertical shear for supercells and organized/upscale- coalescing multicells, the latter being most commonly progged over parts of eastern CO and northwestern KS (where wind probabilities are relatively maximized). Low-level hodographs should be relatively maximized in size over western NE, and rather elongated over a broader swath of the central High Plains, supporting large to significant hail production. ...Lower Ohio Valley region... Widely scattered to scattered, multicell thunderstorms are expected to develop this afternoon and focus mainly near the front and prefrontal outflow/differential-heating boundaries, from northern OK to the Lower Great Lakes. The greatest concentration of convection is still expected over the area from the Ozarks to central OH from late afternoon into early evening. Forecast soundings suggest that diurnal heating and rich boundary-layer moisture, represented by upper 60s to lower 70s surface dewpoints, will offset modest mid/upper-level lapse rates enough to support peak/preconvective MLCAPE in the 2500-3500 J/kg range over the Ozarks, to 1000-2000 J/kg in OH. Conversely, low-level and deep-layer shear will be fairly weak overall, and decreasing with southwestward extent. Damaging to severe gusts will be the main concern. A few short- lived convective clusters are possible, with locally maximized potential for severe gusts. ..Edwards/Kerr.. 07/03/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0753 AM CDT Wed Jul 03 2024 Valid 031300Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF THE CENTRAL/NORTHERN HIGH PLAINS... ...SUMMARY... A threat for all severe hazards is possible this afternoon into evening over portions of the central/northern High Plains. Damaging to severe gusts may occur near a separate front, mainly from the Ozarks to Ohio. ...Synopsis... In mid/upper levels, broadly cyclonic flow will continue over much of the northern CONUS from the Pacific Northwest to the Upper Great Lakes, with numerous embedded vorticity maxima and shortwaves of varying amplitudes. Of those, the most important for this outlook will be a shortwave trough now apparent in moisture-channel imagery over northern Rockies. This feature should dig southeastward to southwestern ND, southeastern MT, northwestern WY and southeastern ID by 00Z. By the end of the period (12Z), the trough should extend diagonal across SD, then to southeastern WY and northwestern CO. Subtropical ridging will persist over the Gulf Coast States and portions of southern CA/AZ, with a height weakness in between, over northwestern MX and NM. At the surface, 11Z analysis showed a cold front across Lake Michigan, northwestern IL, central MO, and southeastern KS, becoming quasistationary across northwestern OK and the TX Panhandle to northeastern NM. By 00Z, the front should move to Lake Huron, northwestern OH, southern IN, southern MO, while drifting southward again to northeastern and west-central OK and the southern Panhandle/northern South Plains region of TX. By 12Z, the front should extend over western parts of NY/PA, eastern/southern KY, and north-central AR, becoming a warm front over north-central/ northwestern OK. Cyclogenesis is forecast late this afternoon through this evening along a lee trough over east-central CO, with a cold front developing from the NE Sandhills into northeastern/ central CO by 06Z. By 12Z, the low should migrate to central NE, with warm front over southern IA, and cold front southwestward across western KS to northeastern NM. ...Central/northern High Plains and vicinity... Isolated to scattered thunderstorms are expected to develop this afternoon -- initially over higher terrain near the Palmer and Cheyenne Ridges and near lee trough, increasing in coverage while moving eastward to southeastward over the High Plains. Large hail (some 2+ inches in diameter) and damaging wind (some gusts over 70 mph) are expected over the north-central High Plains, and a couple tornadoes also are possible, mainly in and near western NE where some overlap of favorable moisture and low-level shear is expected. As the mid/upper trough approaches, expect a favorable strengthening of large-scale lift, winds aloft, deep shear, and mass response leading to northward moisture advection/transport, to the north of the southern frontal zone. Optimal moisture return may be precluded by effects of ongoing clouds/precip to reinforce the baroclinic zone over the southern Plains; however, boundary-layer moisture should be sufficient to support development as heating of higher terrain preferentially erodes MLCINH. Steep low/middle-level lapse rates will contribute to development of 1000-2500 J/kg MLCAPE in a corridor from eastern CO and northwestern KS to southwestern SD, decreasing from there westward toward the Bighorns and southward into less-unstable conditions of the Panhandles and northeastern NM. Veering of winds with height east of the lee trough will contribute to favorable vertical shear for supercells and organized/upscale- coalescing multicells, the latter being most commonly progged over parts of eastern CO and northwestern KS (where wind probabilities are relatively maximized). Low-level hodographs should be relatively maximized in size over western NE, and rather elongated over a broader swath of the central High Plains, supporting large to significant hail production. ...Lower Ohio Valley region... Widely scattered to scattered, multicell thunderstorms are expected to develop this afternoon and focus mainly near the front and prefrontal outflow/differential-heating boundaries, from northern OK to the Lower Great Lakes. The greatest concentration of convection is still expected over the area from the Ozarks to central OH from late afternoon into early evening. Forecast soundings suggest that diurnal heating and rich boundary-layer moisture, represented by upper 60s to lower 70s surface dewpoints, will offset modest mid/upper-level lapse rates enough to support peak/preconvective MLCAPE in the 2500-3500 J/kg range over the Ozarks, to 1000-2000 J/kg in OH. Conversely, low-level and deep-layer shear will be fairly weak overall, and decreasing with southwestward extent. Damaging to severe gusts will be the main concern. A few short- lived convective clusters are possible, with locally maximized potential for severe gusts. ..Edwards/Kerr.. 07/03/2024 Read more