Aggregator

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0155 AM CDT Mon Jul 29 2024 Valid 291200Z - 301200Z ...Synopsis... A broad large-scale trough will move slowly eastward across the Northwest during the day, while an expansive upper ridge remains centered over the south-central CONUS. Between these features, moderate (around 30 kt) midlevel west-southwesterly flow will persist across much of the Great Basin into the Northern Rockies and adjacent High Plains. ...Northern Rockies/High Plains and Great Basin... Deep boundary-layer mixing into the enhanced flow aloft from southern NV into southern UT will favor 5-10 percent minimum RH and 15-20 mph sustained southwesterly surface winds. Given at least modestly receptive fuels over the area, elevated fire-weather conditions are expected during the afternoon. Farther north, a modest pressure gradient along the western periphery of a surface trough, coupled with the enhanced flow through a diurnally deepening boundary layer, will yield around 20 mph sustained west-southwesterly surface winds across portions of the northern Rockies/Intermountain West and adjacent High Plains. Over southern ID and north-central MT, these breezy/gusty winds will overlap 15-20 percent afternoon RH, resulting in elevated to spotty critical fire-weather conditions. ..Weinman.. 07/29/2024 ...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 0155 AM CDT Mon Jul 29 2024 Valid 291200Z - 301200Z ...Synopsis... A broad large-scale trough will move slowly eastward across the Northwest during the day, while an expansive upper ridge remains centered over the south-central CONUS. Between these features, moderate (around 30 kt) midlevel west-southwesterly flow will persist across much of the Great Basin into the Northern Rockies and adjacent High Plains. ...Northern Rockies/High Plains and Great Basin... Deep boundary-layer mixing into the enhanced flow aloft from southern NV into southern UT will favor 5-10 percent minimum RH and 15-20 mph sustained southwesterly surface winds. Given at least modestly receptive fuels over the area, elevated fire-weather conditions are expected during the afternoon. Farther north, a modest pressure gradient along the western periphery of a surface trough, coupled with the enhanced flow through a diurnally deepening boundary layer, will yield around 20 mph sustained west-southwesterly surface winds across portions of the northern Rockies/Intermountain West and adjacent High Plains. Over southern ID and north-central MT, these breezy/gusty winds will overlap 15-20 percent afternoon RH, resulting in elevated to spotty critical fire-weather conditions. ..Weinman.. 07/29/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0102 AM CDT Mon Jul 29 2024 Valid 301200Z - 311200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF IOWA...WESTERN ILLINOIS...AND FAR NORTHEAST MISSOURI... ...SUMMARY... Scattered strong to severe storms will be possible across a broad region from the northern Plains to the Midwest, Ohio Valley, and Carolinas. A more concentrated severe wind threat is possible across portions of the Corn Belt. ...Synopsis... On Tuesday, a mid-level trough across the western CONUS will start to advance east across the northern Rockies. This will start to deamplify the mid-level ridge across the northern Plains while another weak trough will advance east across the central Appalachians. At the surface, lee troughing will strengthen somewhat across the Plains with rich moisture extending from the Gulf of Mexico to the Upper Midwest. This will result in a broad region of moderate to strong instability along and south of a stationary boundary which will extend from the Ohio Valley to the Northern Plains. ...Iowa, Northeast Missouri, and West/Northwest Illinois... A remnant convective complex from D1/Monday will likely be in the vicinity of western Iowa at 12Z Tuesday. As the low-level jet weakens Tuesday morning, the convective complex will likely weaken with potentially remnant outflow boundaries in the region. Some guidance indicates a supercell or two persisting along the outflow boundary through the morning and into the afternoon. This is possible given forecast soundings show inhibition eroding by late morning. However, given the lack of greater forcing across the region, this scenario remains uncertain. Some weak ascent is expected across northern Iowa late Tuesday afternoon/evening as a weak shortwave trough approaches from the west and the low-level jet begins to strengthen. Assuming morning convection has not grown upscale and augmented the environment, a very favorable environment should be present with forecast soundings suggesting 3000 to 4000 J/kg MLCAPE, 40 knots of effective shear, and 8.5 to 9 C/km mid-level lapse rates. If storms can develop within this environment, severe weather is likely with rapid growth upscale into a severe wind producing MCS. Despite a pattern favorable for a severe MCS, uncertainties remain given the lack of a clear forcing signal and likely significant impacts from the Day 1 convection. A slight risk has been introduced for the region with the most favorable environment, but adjustments/upgrades may be necessary in later outlooks, once the most favorable corridor becomes more clear. ...Ohio Valley to the Carolinas... A MCS will likely be ongoing at the beginning of the period across Kentucky/Tennessee. Forecast soundings indicate only minimal heating will be needed ahead of this convective complex to erode inhibition with most guidance showing minimal CINH by 15-16Z. Therefore, it is possible this MCS will continue east through the day and eventually reach the Atlantic Coast. Even if the MCS does not strengthen during the late morning and maintain itself through the day, additional thunderstorms are expected (perhaps along a remnant MCV leftover from the MCS) and within the uncapped airmass. 2500-3000 J/kg MLCAPE and around 25 knots of shear (as forecast by NAM/RAP forecast soundings) will be sufficient for a few strong to severe storms Tuesday afternoon/evening. ...Northern Plains... Weak height falls amid moderate to strong instability may lead to some thunderstorm development along a surface trough/dryline across the Dakotas Tuesday afternoon. Given the lack of a consolidated mid-level speed max, deep-layer shear varies significantly within model guidance during the afternoon/evening. This will affect storm organization and intensity. If stronger mid-level flow (30-35+ knots) can overspread the warm sector during the afternoon/evening, a greater severe weather threat may materialize. However, that scenario remains uncertain at this time. ..Bentley.. 07/29/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0102 AM CDT Mon Jul 29 2024 Valid 301200Z - 311200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF IOWA...WESTERN ILLINOIS...AND FAR NORTHEAST MISSOURI... ...SUMMARY... Scattered strong to severe storms will be possible across a broad region from the northern Plains to the Midwest, Ohio Valley, and Carolinas. A more concentrated severe wind threat is possible across portions of the Corn Belt. ...Synopsis... On Tuesday, a mid-level trough across the western CONUS will start to advance east across the northern Rockies. This will start to deamplify the mid-level ridge across the northern Plains while another weak trough will advance east across the central Appalachians. At the surface, lee troughing will strengthen somewhat across the Plains with rich moisture extending from the Gulf of Mexico to the Upper Midwest. This will result in a broad region of moderate to strong instability along and south of a stationary boundary which will extend from the Ohio Valley to the Northern Plains. ...Iowa, Northeast Missouri, and West/Northwest Illinois... A remnant convective complex from D1/Monday will likely be in the vicinity of western Iowa at 12Z Tuesday. As the low-level jet weakens Tuesday morning, the convective complex will likely weaken with potentially remnant outflow boundaries in the region. Some guidance indicates a supercell or two persisting along the outflow boundary through the morning and into the afternoon. This is possible given forecast soundings show inhibition eroding by late morning. However, given the lack of greater forcing across the region, this scenario remains uncertain. Some weak ascent is expected across northern Iowa late Tuesday afternoon/evening as a weak shortwave trough approaches from the west and the low-level jet begins to strengthen. Assuming morning convection has not grown upscale and augmented the environment, a very favorable environment should be present with forecast soundings suggesting 3000 to 4000 J/kg MLCAPE, 40 knots of effective shear, and 8.5 to 9 C/km mid-level lapse rates. If storms can develop within this environment, severe weather is likely with rapid growth upscale into a severe wind producing MCS. Despite a pattern favorable for a severe MCS, uncertainties remain given the lack of a clear forcing signal and likely significant impacts from the Day 1 convection. A slight risk has been introduced for the region with the most favorable environment, but adjustments/upgrades may be necessary in later outlooks, once the most favorable corridor becomes more clear. ...Ohio Valley to the Carolinas... A MCS will likely be ongoing at the beginning of the period across Kentucky/Tennessee. Forecast soundings indicate only minimal heating will be needed ahead of this convective complex to erode inhibition with most guidance showing minimal CINH by 15-16Z. Therefore, it is possible this MCS will continue east through the day and eventually reach the Atlantic Coast. Even if the MCS does not strengthen during the late morning and maintain itself through the day, additional thunderstorms are expected (perhaps along a remnant MCV leftover from the MCS) and within the uncapped airmass. 2500-3000 J/kg MLCAPE and around 25 knots of shear (as forecast by NAM/RAP forecast soundings) will be sufficient for a few strong to severe storms Tuesday afternoon/evening. ...Northern Plains... Weak height falls amid moderate to strong instability may lead to some thunderstorm development along a surface trough/dryline across the Dakotas Tuesday afternoon. Given the lack of a consolidated mid-level speed max, deep-layer shear varies significantly within model guidance during the afternoon/evening. This will affect storm organization and intensity. If stronger mid-level flow (30-35+ knots) can overspread the warm sector during the afternoon/evening, a greater severe weather threat may materialize. However, that scenario remains uncertain at this time. ..Bentley.. 07/29/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0102 AM CDT Mon Jul 29 2024 Valid 301200Z - 311200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF IOWA...WESTERN ILLINOIS...AND FAR NORTHEAST MISSOURI... ...SUMMARY... Scattered strong to severe storms will be possible across a broad region from the northern Plains to the Midwest, Ohio Valley, and Carolinas. A more concentrated severe wind threat is possible across portions of the Corn Belt. ...Synopsis... On Tuesday, a mid-level trough across the western CONUS will start to advance east across the northern Rockies. This will start to deamplify the mid-level ridge across the northern Plains while another weak trough will advance east across the central Appalachians. At the surface, lee troughing will strengthen somewhat across the Plains with rich moisture extending from the Gulf of Mexico to the Upper Midwest. This will result in a broad region of moderate to strong instability along and south of a stationary boundary which will extend from the Ohio Valley to the Northern Plains. ...Iowa, Northeast Missouri, and West/Northwest Illinois... A remnant convective complex from D1/Monday will likely be in the vicinity of western Iowa at 12Z Tuesday. As the low-level jet weakens Tuesday morning, the convective complex will likely weaken with potentially remnant outflow boundaries in the region. Some guidance indicates a supercell or two persisting along the outflow boundary through the morning and into the afternoon. This is possible given forecast soundings show inhibition eroding by late morning. However, given the lack of greater forcing across the region, this scenario remains uncertain. Some weak ascent is expected across northern Iowa late Tuesday afternoon/evening as a weak shortwave trough approaches from the west and the low-level jet begins to strengthen. Assuming morning convection has not grown upscale and augmented the environment, a very favorable environment should be present with forecast soundings suggesting 3000 to 4000 J/kg MLCAPE, 40 knots of effective shear, and 8.5 to 9 C/km mid-level lapse rates. If storms can develop within this environment, severe weather is likely with rapid growth upscale into a severe wind producing MCS. Despite a pattern favorable for a severe MCS, uncertainties remain given the lack of a clear forcing signal and likely significant impacts from the Day 1 convection. A slight risk has been introduced for the region with the most favorable environment, but adjustments/upgrades may be necessary in later outlooks, once the most favorable corridor becomes more clear. ...Ohio Valley to the Carolinas... A MCS will likely be ongoing at the beginning of the period across Kentucky/Tennessee. Forecast soundings indicate only minimal heating will be needed ahead of this convective complex to erode inhibition with most guidance showing minimal CINH by 15-16Z. Therefore, it is possible this MCS will continue east through the day and eventually reach the Atlantic Coast. Even if the MCS does not strengthen during the late morning and maintain itself through the day, additional thunderstorms are expected (perhaps along a remnant MCV leftover from the MCS) and within the uncapped airmass. 2500-3000 J/kg MLCAPE and around 25 knots of shear (as forecast by NAM/RAP forecast soundings) will be sufficient for a few strong to severe storms Tuesday afternoon/evening. ...Northern Plains... Weak height falls amid moderate to strong instability may lead to some thunderstorm development along a surface trough/dryline across the Dakotas Tuesday afternoon. Given the lack of a consolidated mid-level speed max, deep-layer shear varies significantly within model guidance during the afternoon/evening. This will affect storm organization and intensity. If stronger mid-level flow (30-35+ knots) can overspread the warm sector during the afternoon/evening, a greater severe weather threat may materialize. However, that scenario remains uncertain at this time. ..Bentley.. 07/29/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0102 AM CDT Mon Jul 29 2024 Valid 301200Z - 311200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF IOWA...WESTERN ILLINOIS...AND FAR NORTHEAST MISSOURI... ...SUMMARY... Scattered strong to severe storms will be possible across a broad region from the northern Plains to the Midwest, Ohio Valley, and Carolinas. A more concentrated severe wind threat is possible across portions of the Corn Belt. ...Synopsis... On Tuesday, a mid-level trough across the western CONUS will start to advance east across the northern Rockies. This will start to deamplify the mid-level ridge across the northern Plains while another weak trough will advance east across the central Appalachians. At the surface, lee troughing will strengthen somewhat across the Plains with rich moisture extending from the Gulf of Mexico to the Upper Midwest. This will result in a broad region of moderate to strong instability along and south of a stationary boundary which will extend from the Ohio Valley to the Northern Plains. ...Iowa, Northeast Missouri, and West/Northwest Illinois... A remnant convective complex from D1/Monday will likely be in the vicinity of western Iowa at 12Z Tuesday. As the low-level jet weakens Tuesday morning, the convective complex will likely weaken with potentially remnant outflow boundaries in the region. Some guidance indicates a supercell or two persisting along the outflow boundary through the morning and into the afternoon. This is possible given forecast soundings show inhibition eroding by late morning. However, given the lack of greater forcing across the region, this scenario remains uncertain. Some weak ascent is expected across northern Iowa late Tuesday afternoon/evening as a weak shortwave trough approaches from the west and the low-level jet begins to strengthen. Assuming morning convection has not grown upscale and augmented the environment, a very favorable environment should be present with forecast soundings suggesting 3000 to 4000 J/kg MLCAPE, 40 knots of effective shear, and 8.5 to 9 C/km mid-level lapse rates. If storms can develop within this environment, severe weather is likely with rapid growth upscale into a severe wind producing MCS. Despite a pattern favorable for a severe MCS, uncertainties remain given the lack of a clear forcing signal and likely significant impacts from the Day 1 convection. A slight risk has been introduced for the region with the most favorable environment, but adjustments/upgrades may be necessary in later outlooks, once the most favorable corridor becomes more clear. ...Ohio Valley to the Carolinas... A MCS will likely be ongoing at the beginning of the period across Kentucky/Tennessee. Forecast soundings indicate only minimal heating will be needed ahead of this convective complex to erode inhibition with most guidance showing minimal CINH by 15-16Z. Therefore, it is possible this MCS will continue east through the day and eventually reach the Atlantic Coast. Even if the MCS does not strengthen during the late morning and maintain itself through the day, additional thunderstorms are expected (perhaps along a remnant MCV leftover from the MCS) and within the uncapped airmass. 2500-3000 J/kg MLCAPE and around 25 knots of shear (as forecast by NAM/RAP forecast soundings) will be sufficient for a few strong to severe storms Tuesday afternoon/evening. ...Northern Plains... Weak height falls amid moderate to strong instability may lead to some thunderstorm development along a surface trough/dryline across the Dakotas Tuesday afternoon. Given the lack of a consolidated mid-level speed max, deep-layer shear varies significantly within model guidance during the afternoon/evening. This will affect storm organization and intensity. If stronger mid-level flow (30-35+ knots) can overspread the warm sector during the afternoon/evening, a greater severe weather threat may materialize. However, that scenario remains uncertain at this time. ..Bentley.. 07/29/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0102 AM CDT Mon Jul 29 2024 Valid 301200Z - 311200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF IOWA...WESTERN ILLINOIS...AND FAR NORTHEAST MISSOURI... ...SUMMARY... Scattered strong to severe storms will be possible across a broad region from the northern Plains to the Midwest, Ohio Valley, and Carolinas. A more concentrated severe wind threat is possible across portions of the Corn Belt. ...Synopsis... On Tuesday, a mid-level trough across the western CONUS will start to advance east across the northern Rockies. This will start to deamplify the mid-level ridge across the northern Plains while another weak trough will advance east across the central Appalachians. At the surface, lee troughing will strengthen somewhat across the Plains with rich moisture extending from the Gulf of Mexico to the Upper Midwest. This will result in a broad region of moderate to strong instability along and south of a stationary boundary which will extend from the Ohio Valley to the Northern Plains. ...Iowa, Northeast Missouri, and West/Northwest Illinois... A remnant convective complex from D1/Monday will likely be in the vicinity of western Iowa at 12Z Tuesday. As the low-level jet weakens Tuesday morning, the convective complex will likely weaken with potentially remnant outflow boundaries in the region. Some guidance indicates a supercell or two persisting along the outflow boundary through the morning and into the afternoon. This is possible given forecast soundings show inhibition eroding by late morning. However, given the lack of greater forcing across the region, this scenario remains uncertain. Some weak ascent is expected across northern Iowa late Tuesday afternoon/evening as a weak shortwave trough approaches from the west and the low-level jet begins to strengthen. Assuming morning convection has not grown upscale and augmented the environment, a very favorable environment should be present with forecast soundings suggesting 3000 to 4000 J/kg MLCAPE, 40 knots of effective shear, and 8.5 to 9 C/km mid-level lapse rates. If storms can develop within this environment, severe weather is likely with rapid growth upscale into a severe wind producing MCS. Despite a pattern favorable for a severe MCS, uncertainties remain given the lack of a clear forcing signal and likely significant impacts from the Day 1 convection. A slight risk has been introduced for the region with the most favorable environment, but adjustments/upgrades may be necessary in later outlooks, once the most favorable corridor becomes more clear. ...Ohio Valley to the Carolinas... A MCS will likely be ongoing at the beginning of the period across Kentucky/Tennessee. Forecast soundings indicate only minimal heating will be needed ahead of this convective complex to erode inhibition with most guidance showing minimal CINH by 15-16Z. Therefore, it is possible this MCS will continue east through the day and eventually reach the Atlantic Coast. Even if the MCS does not strengthen during the late morning and maintain itself through the day, additional thunderstorms are expected (perhaps along a remnant MCV leftover from the MCS) and within the uncapped airmass. 2500-3000 J/kg MLCAPE and around 25 knots of shear (as forecast by NAM/RAP forecast soundings) will be sufficient for a few strong to severe storms Tuesday afternoon/evening. ...Northern Plains... Weak height falls amid moderate to strong instability may lead to some thunderstorm development along a surface trough/dryline across the Dakotas Tuesday afternoon. Given the lack of a consolidated mid-level speed max, deep-layer shear varies significantly within model guidance during the afternoon/evening. This will affect storm organization and intensity. If stronger mid-level flow (30-35+ knots) can overspread the warm sector during the afternoon/evening, a greater severe weather threat may materialize. However, that scenario remains uncertain at this time. ..Bentley.. 07/29/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0102 AM CDT Mon Jul 29 2024 Valid 301200Z - 311200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF IOWA...WESTERN ILLINOIS...AND FAR NORTHEAST MISSOURI... ...SUMMARY... Scattered strong to severe storms will be possible across a broad region from the northern Plains to the Midwest, Ohio Valley, and Carolinas. A more concentrated severe wind threat is possible across portions of the Corn Belt. ...Synopsis... On Tuesday, a mid-level trough across the western CONUS will start to advance east across the northern Rockies. This will start to deamplify the mid-level ridge across the northern Plains while another weak trough will advance east across the central Appalachians. At the surface, lee troughing will strengthen somewhat across the Plains with rich moisture extending from the Gulf of Mexico to the Upper Midwest. This will result in a broad region of moderate to strong instability along and south of a stationary boundary which will extend from the Ohio Valley to the Northern Plains. ...Iowa, Northeast Missouri, and West/Northwest Illinois... A remnant convective complex from D1/Monday will likely be in the vicinity of western Iowa at 12Z Tuesday. As the low-level jet weakens Tuesday morning, the convective complex will likely weaken with potentially remnant outflow boundaries in the region. Some guidance indicates a supercell or two persisting along the outflow boundary through the morning and into the afternoon. This is possible given forecast soundings show inhibition eroding by late morning. However, given the lack of greater forcing across the region, this scenario remains uncertain. Some weak ascent is expected across northern Iowa late Tuesday afternoon/evening as a weak shortwave trough approaches from the west and the low-level jet begins to strengthen. Assuming morning convection has not grown upscale and augmented the environment, a very favorable environment should be present with forecast soundings suggesting 3000 to 4000 J/kg MLCAPE, 40 knots of effective shear, and 8.5 to 9 C/km mid-level lapse rates. If storms can develop within this environment, severe weather is likely with rapid growth upscale into a severe wind producing MCS. Despite a pattern favorable for a severe MCS, uncertainties remain given the lack of a clear forcing signal and likely significant impacts from the Day 1 convection. A slight risk has been introduced for the region with the most favorable environment, but adjustments/upgrades may be necessary in later outlooks, once the most favorable corridor becomes more clear. ...Ohio Valley to the Carolinas... A MCS will likely be ongoing at the beginning of the period across Kentucky/Tennessee. Forecast soundings indicate only minimal heating will be needed ahead of this convective complex to erode inhibition with most guidance showing minimal CINH by 15-16Z. Therefore, it is possible this MCS will continue east through the day and eventually reach the Atlantic Coast. Even if the MCS does not strengthen during the late morning and maintain itself through the day, additional thunderstorms are expected (perhaps along a remnant MCV leftover from the MCS) and within the uncapped airmass. 2500-3000 J/kg MLCAPE and around 25 knots of shear (as forecast by NAM/RAP forecast soundings) will be sufficient for a few strong to severe storms Tuesday afternoon/evening. ...Northern Plains... Weak height falls amid moderate to strong instability may lead to some thunderstorm development along a surface trough/dryline across the Dakotas Tuesday afternoon. Given the lack of a consolidated mid-level speed max, deep-layer shear varies significantly within model guidance during the afternoon/evening. This will affect storm organization and intensity. If stronger mid-level flow (30-35+ knots) can overspread the warm sector during the afternoon/evening, a greater severe weather threat may materialize. However, that scenario remains uncertain at this time. ..Bentley.. 07/29/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1259 AM CDT Mon Jul 29 2024 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE DAKOTAS INTO NORTHERN NEBRASKA...AND ALSO ACROSS SOUTHERN ILLINOIS/INDIANA INTO CENTRAL KENTUCKY... ...SUMMARY... Scattered strong to severe storms are possible across parts of the central and northern Plains this afternoon and evening, and also across parts of the Midwest and Ohio Valley through the day. ...Northern/central Great Plains into the Upper Midwest... A broad upper trough with multiple embedded shortwaves will again be in place across parts of the northern Rockies into the central/northern Plains today. Steep midlevel lapse rates and strong heating will support moderate to locally strong buoyancy by afternoon across parts of the Dakotas into Nebraska. As MLCINH decreases through the afternoon, most guidance suggests at least widely scattered storm development near a surface trough from the western Dakotas into northwest NE. Effective shear of 35-45 kt will support some threat for supercells, with an attendant threat of large hail (possibly in excess of 2 inches in diameter) and localized severe gusts. With time, evolution into one or more outflow driven clusters will be possible, with an increasing threat of damaging/severe gusts (potentially in excess of 75 mph). Longevity for any of these potential clusters into late tonight is uncertain, but some threat for damaging/locally severe gusts could spread into parts of IA and southern MN before a more definitive weakening trend occurs. ...Parts of the OH/MS Valley into the TN Valley and Southeast... An MCS may be ongoing at the start of the period somewhere from far eastern MO into IL. While the organization and severity of this system during the morning is uncertain, at least isolated damaging gusts could spread southeastward into parts of the OH/TN Valley through midday. In the wake of morning convection, moderate westerly low-level flow will help to modify the remnant outflow, with redevelopment possible by late afternoon into the evening within a warm-advection regime. Most guidance suggests a tendency toward clustering and possible MCS redevelopment by early evening, with a renewed threat for damaging wind. A couple supercells could also evolve within the modifying outflow regime, with an attendant threat for isolated hail and a tornado or two. A Slight Risk has been added from southern IL/IN into central KY, where confidence is currently greatest in some severe threat from both the morning convection and later redevelopment. Some adjustments will likely be needed based on the evolution of early-day convection. Farther southeast, some threat for a few strong storms with isolated damaging-wind potential appears evident from the TN Valley into parts of GA and the Carolinas, within a modest northwesterly flow regime. ...Northern Mid Atlantic vicinity... As a midlevel cyclone moves northward across New England through the day today, strengthening northwesterly mid/upper-level flow will overspread parts of the Mid Atlantic. A few strong storms could develop within this regime during the afternoon, with moderate buoyancy and effective shear of 30-35 kt supporting some potential for isolated damaging gusts and hail. ..Dean/Weinman.. 07/29/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1259 AM CDT Mon Jul 29 2024 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE DAKOTAS INTO NORTHERN NEBRASKA...AND ALSO ACROSS SOUTHERN ILLINOIS/INDIANA INTO CENTRAL KENTUCKY... ...SUMMARY... Scattered strong to severe storms are possible across parts of the central and northern Plains this afternoon and evening, and also across parts of the Midwest and Ohio Valley through the day. ...Northern/central Great Plains into the Upper Midwest... A broad upper trough with multiple embedded shortwaves will again be in place across parts of the northern Rockies into the central/northern Plains today. Steep midlevel lapse rates and strong heating will support moderate to locally strong buoyancy by afternoon across parts of the Dakotas into Nebraska. As MLCINH decreases through the afternoon, most guidance suggests at least widely scattered storm development near a surface trough from the western Dakotas into northwest NE. Effective shear of 35-45 kt will support some threat for supercells, with an attendant threat of large hail (possibly in excess of 2 inches in diameter) and localized severe gusts. With time, evolution into one or more outflow driven clusters will be possible, with an increasing threat of damaging/severe gusts (potentially in excess of 75 mph). Longevity for any of these potential clusters into late tonight is uncertain, but some threat for damaging/locally severe gusts could spread into parts of IA and southern MN before a more definitive weakening trend occurs. ...Parts of the OH/MS Valley into the TN Valley and Southeast... An MCS may be ongoing at the start of the period somewhere from far eastern MO into IL. While the organization and severity of this system during the morning is uncertain, at least isolated damaging gusts could spread southeastward into parts of the OH/TN Valley through midday. In the wake of morning convection, moderate westerly low-level flow will help to modify the remnant outflow, with redevelopment possible by late afternoon into the evening within a warm-advection regime. Most guidance suggests a tendency toward clustering and possible MCS redevelopment by early evening, with a renewed threat for damaging wind. A couple supercells could also evolve within the modifying outflow regime, with an attendant threat for isolated hail and a tornado or two. A Slight Risk has been added from southern IL/IN into central KY, where confidence is currently greatest in some severe threat from both the morning convection and later redevelopment. Some adjustments will likely be needed based on the evolution of early-day convection. Farther southeast, some threat for a few strong storms with isolated damaging-wind potential appears evident from the TN Valley into parts of GA and the Carolinas, within a modest northwesterly flow regime. ...Northern Mid Atlantic vicinity... As a midlevel cyclone moves northward across New England through the day today, strengthening northwesterly mid/upper-level flow will overspread parts of the Mid Atlantic. A few strong storms could develop within this regime during the afternoon, with moderate buoyancy and effective shear of 30-35 kt supporting some potential for isolated damaging gusts and hail. ..Dean/Weinman.. 07/29/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1259 AM CDT Mon Jul 29 2024 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE DAKOTAS INTO NORTHERN NEBRASKA...AND ALSO ACROSS SOUTHERN ILLINOIS/INDIANA INTO CENTRAL KENTUCKY... ...SUMMARY... Scattered strong to severe storms are possible across parts of the central and northern Plains this afternoon and evening, and also across parts of the Midwest and Ohio Valley through the day. ...Northern/central Great Plains into the Upper Midwest... A broad upper trough with multiple embedded shortwaves will again be in place across parts of the northern Rockies into the central/northern Plains today. Steep midlevel lapse rates and strong heating will support moderate to locally strong buoyancy by afternoon across parts of the Dakotas into Nebraska. As MLCINH decreases through the afternoon, most guidance suggests at least widely scattered storm development near a surface trough from the western Dakotas into northwest NE. Effective shear of 35-45 kt will support some threat for supercells, with an attendant threat of large hail (possibly in excess of 2 inches in diameter) and localized severe gusts. With time, evolution into one or more outflow driven clusters will be possible, with an increasing threat of damaging/severe gusts (potentially in excess of 75 mph). Longevity for any of these potential clusters into late tonight is uncertain, but some threat for damaging/locally severe gusts could spread into parts of IA and southern MN before a more definitive weakening trend occurs. ...Parts of the OH/MS Valley into the TN Valley and Southeast... An MCS may be ongoing at the start of the period somewhere from far eastern MO into IL. While the organization and severity of this system during the morning is uncertain, at least isolated damaging gusts could spread southeastward into parts of the OH/TN Valley through midday. In the wake of morning convection, moderate westerly low-level flow will help to modify the remnant outflow, with redevelopment possible by late afternoon into the evening within a warm-advection regime. Most guidance suggests a tendency toward clustering and possible MCS redevelopment by early evening, with a renewed threat for damaging wind. A couple supercells could also evolve within the modifying outflow regime, with an attendant threat for isolated hail and a tornado or two. A Slight Risk has been added from southern IL/IN into central KY, where confidence is currently greatest in some severe threat from both the morning convection and later redevelopment. Some adjustments will likely be needed based on the evolution of early-day convection. Farther southeast, some threat for a few strong storms with isolated damaging-wind potential appears evident from the TN Valley into parts of GA and the Carolinas, within a modest northwesterly flow regime. ...Northern Mid Atlantic vicinity... As a midlevel cyclone moves northward across New England through the day today, strengthening northwesterly mid/upper-level flow will overspread parts of the Mid Atlantic. A few strong storms could develop within this regime during the afternoon, with moderate buoyancy and effective shear of 30-35 kt supporting some potential for isolated damaging gusts and hail. ..Dean/Weinman.. 07/29/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1259 AM CDT Mon Jul 29 2024 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE DAKOTAS INTO NORTHERN NEBRASKA...AND ALSO ACROSS SOUTHERN ILLINOIS/INDIANA INTO CENTRAL KENTUCKY... ...SUMMARY... Scattered strong to severe storms are possible across parts of the central and northern Plains this afternoon and evening, and also across parts of the Midwest and Ohio Valley through the day. ...Northern/central Great Plains into the Upper Midwest... A broad upper trough with multiple embedded shortwaves will again be in place across parts of the northern Rockies into the central/northern Plains today. Steep midlevel lapse rates and strong heating will support moderate to locally strong buoyancy by afternoon across parts of the Dakotas into Nebraska. As MLCINH decreases through the afternoon, most guidance suggests at least widely scattered storm development near a surface trough from the western Dakotas into northwest NE. Effective shear of 35-45 kt will support some threat for supercells, with an attendant threat of large hail (possibly in excess of 2 inches in diameter) and localized severe gusts. With time, evolution into one or more outflow driven clusters will be possible, with an increasing threat of damaging/severe gusts (potentially in excess of 75 mph). Longevity for any of these potential clusters into late tonight is uncertain, but some threat for damaging/locally severe gusts could spread into parts of IA and southern MN before a more definitive weakening trend occurs. ...Parts of the OH/MS Valley into the TN Valley and Southeast... An MCS may be ongoing at the start of the period somewhere from far eastern MO into IL. While the organization and severity of this system during the morning is uncertain, at least isolated damaging gusts could spread southeastward into parts of the OH/TN Valley through midday. In the wake of morning convection, moderate westerly low-level flow will help to modify the remnant outflow, with redevelopment possible by late afternoon into the evening within a warm-advection regime. Most guidance suggests a tendency toward clustering and possible MCS redevelopment by early evening, with a renewed threat for damaging wind. A couple supercells could also evolve within the modifying outflow regime, with an attendant threat for isolated hail and a tornado or two. A Slight Risk has been added from southern IL/IN into central KY, where confidence is currently greatest in some severe threat from both the morning convection and later redevelopment. Some adjustments will likely be needed based on the evolution of early-day convection. Farther southeast, some threat for a few strong storms with isolated damaging-wind potential appears evident from the TN Valley into parts of GA and the Carolinas, within a modest northwesterly flow regime. ...Northern Mid Atlantic vicinity... As a midlevel cyclone moves northward across New England through the day today, strengthening northwesterly mid/upper-level flow will overspread parts of the Mid Atlantic. A few strong storms could develop within this regime during the afternoon, with moderate buoyancy and effective shear of 30-35 kt supporting some potential for isolated damaging gusts and hail. ..Dean/Weinman.. 07/29/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1259 AM CDT Mon Jul 29 2024 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE DAKOTAS INTO NORTHERN NEBRASKA...AND ALSO ACROSS SOUTHERN ILLINOIS/INDIANA INTO CENTRAL KENTUCKY... ...SUMMARY... Scattered strong to severe storms are possible across parts of the central and northern Plains this afternoon and evening, and also across parts of the Midwest and Ohio Valley through the day. ...Northern/central Great Plains into the Upper Midwest... A broad upper trough with multiple embedded shortwaves will again be in place across parts of the northern Rockies into the central/northern Plains today. Steep midlevel lapse rates and strong heating will support moderate to locally strong buoyancy by afternoon across parts of the Dakotas into Nebraska. As MLCINH decreases through the afternoon, most guidance suggests at least widely scattered storm development near a surface trough from the western Dakotas into northwest NE. Effective shear of 35-45 kt will support some threat for supercells, with an attendant threat of large hail (possibly in excess of 2 inches in diameter) and localized severe gusts. With time, evolution into one or more outflow driven clusters will be possible, with an increasing threat of damaging/severe gusts (potentially in excess of 75 mph). Longevity for any of these potential clusters into late tonight is uncertain, but some threat for damaging/locally severe gusts could spread into parts of IA and southern MN before a more definitive weakening trend occurs. ...Parts of the OH/MS Valley into the TN Valley and Southeast... An MCS may be ongoing at the start of the period somewhere from far eastern MO into IL. While the organization and severity of this system during the morning is uncertain, at least isolated damaging gusts could spread southeastward into parts of the OH/TN Valley through midday. In the wake of morning convection, moderate westerly low-level flow will help to modify the remnant outflow, with redevelopment possible by late afternoon into the evening within a warm-advection regime. Most guidance suggests a tendency toward clustering and possible MCS redevelopment by early evening, with a renewed threat for damaging wind. A couple supercells could also evolve within the modifying outflow regime, with an attendant threat for isolated hail and a tornado or two. A Slight Risk has been added from southern IL/IN into central KY, where confidence is currently greatest in some severe threat from both the morning convection and later redevelopment. Some adjustments will likely be needed based on the evolution of early-day convection. Farther southeast, some threat for a few strong storms with isolated damaging-wind potential appears evident from the TN Valley into parts of GA and the Carolinas, within a modest northwesterly flow regime. ...Northern Mid Atlantic vicinity... As a midlevel cyclone moves northward across New England through the day today, strengthening northwesterly mid/upper-level flow will overspread parts of the Mid Atlantic. A few strong storms could develop within this regime during the afternoon, with moderate buoyancy and effective shear of 30-35 kt supporting some potential for isolated damaging gusts and hail. ..Dean/Weinman.. 07/29/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1259 AM CDT Mon Jul 29 2024 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE DAKOTAS INTO NORTHERN NEBRASKA...AND ALSO ACROSS SOUTHERN ILLINOIS/INDIANA INTO CENTRAL KENTUCKY... ...SUMMARY... Scattered strong to severe storms are possible across parts of the central and northern Plains this afternoon and evening, and also across parts of the Midwest and Ohio Valley through the day. ...Northern/central Great Plains into the Upper Midwest... A broad upper trough with multiple embedded shortwaves will again be in place across parts of the northern Rockies into the central/northern Plains today. Steep midlevel lapse rates and strong heating will support moderate to locally strong buoyancy by afternoon across parts of the Dakotas into Nebraska. As MLCINH decreases through the afternoon, most guidance suggests at least widely scattered storm development near a surface trough from the western Dakotas into northwest NE. Effective shear of 35-45 kt will support some threat for supercells, with an attendant threat of large hail (possibly in excess of 2 inches in diameter) and localized severe gusts. With time, evolution into one or more outflow driven clusters will be possible, with an increasing threat of damaging/severe gusts (potentially in excess of 75 mph). Longevity for any of these potential clusters into late tonight is uncertain, but some threat for damaging/locally severe gusts could spread into parts of IA and southern MN before a more definitive weakening trend occurs. ...Parts of the OH/MS Valley into the TN Valley and Southeast... An MCS may be ongoing at the start of the period somewhere from far eastern MO into IL. While the organization and severity of this system during the morning is uncertain, at least isolated damaging gusts could spread southeastward into parts of the OH/TN Valley through midday. In the wake of morning convection, moderate westerly low-level flow will help to modify the remnant outflow, with redevelopment possible by late afternoon into the evening within a warm-advection regime. Most guidance suggests a tendency toward clustering and possible MCS redevelopment by early evening, with a renewed threat for damaging wind. A couple supercells could also evolve within the modifying outflow regime, with an attendant threat for isolated hail and a tornado or two. A Slight Risk has been added from southern IL/IN into central KY, where confidence is currently greatest in some severe threat from both the morning convection and later redevelopment. Some adjustments will likely be needed based on the evolution of early-day convection. Farther southeast, some threat for a few strong storms with isolated damaging-wind potential appears evident from the TN Valley into parts of GA and the Carolinas, within a modest northwesterly flow regime. ...Northern Mid Atlantic vicinity... As a midlevel cyclone moves northward across New England through the day today, strengthening northwesterly mid/upper-level flow will overspread parts of the Mid Atlantic. A few strong storms could develop within this regime during the afternoon, with moderate buoyancy and effective shear of 30-35 kt supporting some potential for isolated damaging gusts and hail. ..Dean/Weinman.. 07/29/2024 Read more

000
ABPZ20 KNHC 290501
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 PM PDT Sun Jul 28 2024

For the eastern North Pacific...east of 140 degrees west longitude:

South of Southern Mexico:
An area of disorganized showers and thunderstorms located a few
hundred miles south of the southern coast of Mexico is associated
with a tropical wave. Environmental conditions appear conducive for
gradual development of this system, and a tropical depression is
likely to form during the middle part of the week. The system is
forecast to move westward to west-northwestward at 10 to 15 mph
during the next several days, remaining offshore of the southern
coast of Mexico.
* Formation chance through 48 hours...low...20 percent.
* Formation chance through 7 days...high...80 percent.

Western East Pacific:
Another tropical wave located well to the southwest of the southern
tip of the Baja California Peninsula continues to produce some
disorganized showers and thunderstorms. Gradual development of
this system is possible during the middle and latter parts of the
week while it moves westward to west-northwestward at about 10 mph
across the western portion of the basin.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...low...30 percent.

South of Central America and Southern Mexico:
An area of low pressure could form offshore of the coast of Central
America and southern Mexico towards the end of the week. Some
gradual development of this system is possible thereafter while it
moves generally westward.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...low...30 percent.

$$
Forecaster Blake

MD 1723 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR PORTIONS OF SOUTHERN SOUTH DAKOTA INTO FAR NORTH-CENTRAL NEBRASKA
Mesoscale Discussion 1723 NWS Storm Prediction Center Norman OK 0900 PM CDT Sun Jul 28 2024 Areas affected...Portions of southern South Dakota into far north-central Nebraska Concerning...Severe potential...Watch possible Valid 290200Z - 290400Z Probability of Watch Issuance...40 percent SUMMARY...The potential for a few severe wind gusts and isolated large hail may persist across portions of southern South Dakota into far north-central Nebraska for the next few hours. The need for a watch is still uncertain. DISCUSSION...As of 0150Z, thunderstorms have recently increased in coverage and intensity across portions of southwestern South Dakota -- where a large cold pool has developed. These storms are beginning to intercept a plume of post-frontal/recycled boundary-layer moisture (lower/middle 60s dewpoints) north of a surface low centered over central Nebraska. Steep midlevel lapse rates (sampled by regional 00Z soundings) above the destabilized boundary layer could support the maintenance or perhaps intensification of these storms as they continue east-southeastward during the next few hours. And, a long/straight hodograph (around 45 kt of 0-6km shear per the KUDX VWP) will conditionally support organized convection, including the potential for supercell structures and/or line segments. Isolated large hail (some possibly very large) and severe gusts are possible with any longer-lived storms. Generally weak large-scale ascent and gradually increasing nocturnal stability cast uncertainty on the overall coverage of severe threat. Therefore, convective trends will be monitored closely. ..Weinman/Hart.. 07/29/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...FSD...ABR...LBF...UNR... LAT...LON 43230243 43430308 43630341 43840341 43980334 44150299 44220250 44270187 44270115 44069983 43629870 43139863 42879907 42890016 43230243 Read more

MD 1722 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PARTS OF NORTHWESTERN INTO CENTRAL KANSAS
Mesoscale Discussion 1722 NWS Storm Prediction Center Norman OK 0849 PM CDT Sun Jul 28 2024 Areas affected...parts of northwestern into central Kansas Concerning...Severe potential...Watch unlikely Valid 290149Z - 290345Z Probability of Watch Issuance...20 percent SUMMARY...An isolated long-lived supercell has been producing large hail and locally severe wind gusts along its path now approaching the Hayes KS vicinity. This may persist into the 9-10 PM CDT time frame, before a rapid weakening commences. DISCUSSION...Within a favorable lower/mid-tropospheric warm advection regime, near the northeastern periphery of mid/upper ridging shifting east of the Rockies, an isolated supercell has been maintained for a couple of hours now. Despite the presence of lingering inhibition beneath warm/warming mid-levels, strong shear beneath a broadly anticyclonic upper jet (including 50-70 kt around 300 mb) nosing across the Colorado Rockies through northwestern Kansas probably has contributed to the sustenance of this cell, coupled with persistent moderate south/southeasterly inflow of unstable air. Inflow appears to have been characterized by CAPE on the order of 1500 J/kg, as the storm has taken on an increasing rightward propagation toward the Hayes KS vicinity. However, based on observational data and objective analysis, it appears that it may begin to acquire at least somewhat drier and less unstable inflow within the next hour or two. Coupled with increasing inhibition associated with the loss of daytime heating, the cell seems likely to weaken, and weakening/dissipation may be fairly rapid once this begins. ..Kerr/Hart.. 07/29/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...ICT...GID...DDC...GLD... LAT...LON 39300008 38929892 38689886 38619947 38890026 39300008 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0800 PM CDT Sun Jul 28 2024 Valid 290100Z - 291200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE CENTRAL/NORTHERN PLAINS INTO IOWA... ...SUMMARY... Scattered strong to severe thunderstorms remain possible tonight for parts of the northern/central Plains into the Upper Midwest. Large hail and severe/damaging winds are expected be the main threats. ...Parts of SD/NE/KS... Storms have generally remained rather isolated this afternoon and early evening from parts of SD into southwest NE/northwest KS. However, a conditionally favorable environment for organized storms will persist across the region through much of tonight, despite gradually increasing MLCINH. MLCAPE of 1000-2000 J/kg and effective shear of 30-40 kt will support a continued threat of isolated supercells this evening, with continued potential for hail and localized severe gusts. It remains possible that the cluster of storms across western SD could undergo modest upscale growth and propagate east-southeastward tonight with a more organized severe wind threat. However, this scenario continues to be uncertain, given increasing MLCINH and the lack of stronger low-level flow (with the primary low-level jet displaced well to the southeast). Farther south, some increase in storm coverage remains possible across parts of NE into northwest KS through mid evening, before MLCINH becomes increasingly prohibitive later tonight. Any stronger cells/clusters in this region would pose some risk of hail and strong to severe gusts. ...IA/MO... A persistent cluster of storms associated with an MCV across northwest IA has remained subsevere thus far today, though some threat for locally damaging wind cannot be ruled out this evening in association with this cluster. Some further increase in storm coverage is possible with time tonight, as a low-level jet becomes focused into the region. While deep-layer will remain rather modest, there is some potential for a larger MCS to evolve out of the ongoing convection, which could eventually propagate southeastward into a moderately unstable environment across parts of southeast IA, northeast MO, and western IL, with some threat of isolated damaging gusts. ...MN... A few stronger storms remain possible across parts of MN, where moderate buoyancy persists this evening outside of areas already influenced by substantial convection. Rather weak deep-layer shear should tend to limit storm organization, but locally damaging gusts cannot be ruled out before convection generally weakens later tonight. ..Dean.. 07/29/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0800 PM CDT Sun Jul 28 2024 Valid 290100Z - 291200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE CENTRAL/NORTHERN PLAINS INTO IOWA... ...SUMMARY... Scattered strong to severe thunderstorms remain possible tonight for parts of the northern/central Plains into the Upper Midwest. Large hail and severe/damaging winds are expected be the main threats. ...Parts of SD/NE/KS... Storms have generally remained rather isolated this afternoon and early evening from parts of SD into southwest NE/northwest KS. However, a conditionally favorable environment for organized storms will persist across the region through much of tonight, despite gradually increasing MLCINH. MLCAPE of 1000-2000 J/kg and effective shear of 30-40 kt will support a continued threat of isolated supercells this evening, with continued potential for hail and localized severe gusts. It remains possible that the cluster of storms across western SD could undergo modest upscale growth and propagate east-southeastward tonight with a more organized severe wind threat. However, this scenario continues to be uncertain, given increasing MLCINH and the lack of stronger low-level flow (with the primary low-level jet displaced well to the southeast). Farther south, some increase in storm coverage remains possible across parts of NE into northwest KS through mid evening, before MLCINH becomes increasingly prohibitive later tonight. Any stronger cells/clusters in this region would pose some risk of hail and strong to severe gusts. ...IA/MO... A persistent cluster of storms associated with an MCV across northwest IA has remained subsevere thus far today, though some threat for locally damaging wind cannot be ruled out this evening in association with this cluster. Some further increase in storm coverage is possible with time tonight, as a low-level jet becomes focused into the region. While deep-layer will remain rather modest, there is some potential for a larger MCS to evolve out of the ongoing convection, which could eventually propagate southeastward into a moderately unstable environment across parts of southeast IA, northeast MO, and western IL, with some threat of isolated damaging gusts. ...MN... A few stronger storms remain possible across parts of MN, where moderate buoyancy persists this evening outside of areas already influenced by substantial convection. Rather weak deep-layer shear should tend to limit storm organization, but locally damaging gusts cannot be ruled out before convection generally weakens later tonight. ..Dean.. 07/29/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0800 PM CDT Sun Jul 28 2024 Valid 290100Z - 291200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE CENTRAL/NORTHERN PLAINS INTO IOWA... ...SUMMARY... Scattered strong to severe thunderstorms remain possible tonight for parts of the northern/central Plains into the Upper Midwest. Large hail and severe/damaging winds are expected be the main threats. ...Parts of SD/NE/KS... Storms have generally remained rather isolated this afternoon and early evening from parts of SD into southwest NE/northwest KS. However, a conditionally favorable environment for organized storms will persist across the region through much of tonight, despite gradually increasing MLCINH. MLCAPE of 1000-2000 J/kg and effective shear of 30-40 kt will support a continued threat of isolated supercells this evening, with continued potential for hail and localized severe gusts. It remains possible that the cluster of storms across western SD could undergo modest upscale growth and propagate east-southeastward tonight with a more organized severe wind threat. However, this scenario continues to be uncertain, given increasing MLCINH and the lack of stronger low-level flow (with the primary low-level jet displaced well to the southeast). Farther south, some increase in storm coverage remains possible across parts of NE into northwest KS through mid evening, before MLCINH becomes increasingly prohibitive later tonight. Any stronger cells/clusters in this region would pose some risk of hail and strong to severe gusts. ...IA/MO... A persistent cluster of storms associated with an MCV across northwest IA has remained subsevere thus far today, though some threat for locally damaging wind cannot be ruled out this evening in association with this cluster. Some further increase in storm coverage is possible with time tonight, as a low-level jet becomes focused into the region. While deep-layer will remain rather modest, there is some potential for a larger MCS to evolve out of the ongoing convection, which could eventually propagate southeastward into a moderately unstable environment across parts of southeast IA, northeast MO, and western IL, with some threat of isolated damaging gusts. ...MN... A few stronger storms remain possible across parts of MN, where moderate buoyancy persists this evening outside of areas already influenced by substantial convection. Rather weak deep-layer shear should tend to limit storm organization, but locally damaging gusts cannot be ruled out before convection generally weakens later tonight. ..Dean.. 07/29/2024 Read more