Severe Storms

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0230 AM CDT Sun May 05 2024 Valid 071200Z - 081200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MID-SOUTH INTO THE OHIO VALLEY... ...SUMMARY... Scattered severe thunderstorms appear possible Tuesday from the Mid-South northeastward into parts of the Ohio Valley. ...Synopsis... A large, closed upper cyclone over the northern Plains should move little on Tuesday. A lead mid-level shortwave trough with attendant enhanced mid-level jet is forecast to move quickly northeastward across the Upper Midwest and Great Lakes through the day. The southern fringe of this shortwave trough and modest large-scale ascent should overspread parts of the Mid-South into the OH Valley Tuesday afternoon. At the surface, a deep low over ND should slowly occlude, while a weak secondary low develops northeastward in tandem with the shortwave trough across parts of the Upper Midwest and Great Lakes. A moist and unstable airmass should exist along and southeast of a convectively reinforced surface front, generally extending northeastward from the ArkLaTex vicinity into parts of the mid MS and OH Valleys. ...Mid-South into the Ohio Valley... A line of thunderstorms will probably be ongoing Tuesday morning over parts of AR/MO/IL, associated with convection that developed on Monday across the Plains. This activity may tend to weaken though the morning. But, it could still pose an isolated strong/gusty wind threat. Weak to moderate instability should develop ahead of and to the southwest of these early-day thunderstorms, with greater instability forecast across the Mid-South and lower OH Valley. Deep-layer shear is forecast to be strong enough to support organized convection, including some supercells. However, with mid-level flow generally aligned with the forecast position of the surface boundary, tendency may be for clusters/bowing line segments to prevail. Regardless, scattered strong to severe thunderstorms should spread east-northeastward across the OH Valley Tuesday afternoon and evening, posing a threat for mainly damaging winds and severe hail. Across the Mid-South/TN Valley into AR, the severe threat appears more conditional, owing to this region generally being displaced to the south of the better forcing aloft. An isolated threat for severe hail may develop late in the period (early Wednesday morning) across the Ozarks as low-level flow/ascent increases with a strengthening low-level jet. Given latest model trends and the likelihood for morning convection across the mid MS Valley, it appears that the potential for appreciable destabilization and severe thunderstorms is lower across much of IA, MO, and IL. Have therefore reduced severe probabilities across these areas. ..Gleason.. 05/05/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0230 AM CDT Sun May 05 2024 Valid 071200Z - 081200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MID-SOUTH INTO THE OHIO VALLEY... ...SUMMARY... Scattered severe thunderstorms appear possible Tuesday from the Mid-South northeastward into parts of the Ohio Valley. ...Synopsis... A large, closed upper cyclone over the northern Plains should move little on Tuesday. A lead mid-level shortwave trough with attendant enhanced mid-level jet is forecast to move quickly northeastward across the Upper Midwest and Great Lakes through the day. The southern fringe of this shortwave trough and modest large-scale ascent should overspread parts of the Mid-South into the OH Valley Tuesday afternoon. At the surface, a deep low over ND should slowly occlude, while a weak secondary low develops northeastward in tandem with the shortwave trough across parts of the Upper Midwest and Great Lakes. A moist and unstable airmass should exist along and southeast of a convectively reinforced surface front, generally extending northeastward from the ArkLaTex vicinity into parts of the mid MS and OH Valleys. ...Mid-South into the Ohio Valley... A line of thunderstorms will probably be ongoing Tuesday morning over parts of AR/MO/IL, associated with convection that developed on Monday across the Plains. This activity may tend to weaken though the morning. But, it could still pose an isolated strong/gusty wind threat. Weak to moderate instability should develop ahead of and to the southwest of these early-day thunderstorms, with greater instability forecast across the Mid-South and lower OH Valley. Deep-layer shear is forecast to be strong enough to support organized convection, including some supercells. However, with mid-level flow generally aligned with the forecast position of the surface boundary, tendency may be for clusters/bowing line segments to prevail. Regardless, scattered strong to severe thunderstorms should spread east-northeastward across the OH Valley Tuesday afternoon and evening, posing a threat for mainly damaging winds and severe hail. Across the Mid-South/TN Valley into AR, the severe threat appears more conditional, owing to this region generally being displaced to the south of the better forcing aloft. An isolated threat for severe hail may develop late in the period (early Wednesday morning) across the Ozarks as low-level flow/ascent increases with a strengthening low-level jet. Given latest model trends and the likelihood for morning convection across the mid MS Valley, it appears that the potential for appreciable destabilization and severe thunderstorms is lower across much of IA, MO, and IL. Have therefore reduced severe probabilities across these areas. ..Gleason.. 05/05/2024 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0155 AM CDT Sun May 05 2024 Valid 061200Z - 071200Z ...CRITICAL FIRE WEATHER AREA FOR EASTERN NEW MEXICO INTO THE TEXAS AND OKLAHOMA PANHANDLES... ...Synopsis... An active fire-weather pattern will continue on D2/Monday as a powerful mid-level trough ejects through the Central Plains. Associated dry, windy conditions to the west of a dryline will lead to critical fire-weather conditions across central/eastern NM and the TX/OK Panhandles. By peak heating on Tuesday afternoon, the mid-level trough is expected to become negatively tilted and centered from eastern MT southeastward through central NE/KS. Upstream of the trough axis, a belt of 50-60+ kt westerly mid-level flow is expected from northeastern AZ through the TX/OK Panhandles. Downward momentum mixing, in conjunction with a tightening surface pressure gradient and strong isallobaric flow, will yield persistent and strong surface flow around 20-30 mph during the afternoon and evening. Very dry conditions are also anticipated, with relative humidities as low as 5-10 percent. As a result, high confidence exists in critical meteorological fire-weather conditions across the delineated area. Locally extremely critical conditions are possible, but a few factors preclude highlighting a specific area, including: 1. local fuel state due to bands of wetting precipitation from thunderstorms on Saturday night and Sunday morning, and, 2. whether sustained surface winds will meet extremely critical conditions (30+ mph) for an extended period of time. Elevated/critical meteorological fire-weather conditions will likely develop to the northeast (e.g., southeastern CO and southwestern KS) and east (e.g., eastern TX/OK Panhandles) of the delineated areas as the dryline mixes eastward on Monday. However, much of these areas received around 0.5+ inches of precipitation recently, which should temper the fire-weather threat immediately behind the dryline. ..Flournoy.. 05/05/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0155 AM CDT Sun May 05 2024 Valid 061200Z - 071200Z ...CRITICAL FIRE WEATHER AREA FOR EASTERN NEW MEXICO INTO THE TEXAS AND OKLAHOMA PANHANDLES... ...Synopsis... An active fire-weather pattern will continue on D2/Monday as a powerful mid-level trough ejects through the Central Plains. Associated dry, windy conditions to the west of a dryline will lead to critical fire-weather conditions across central/eastern NM and the TX/OK Panhandles. By peak heating on Tuesday afternoon, the mid-level trough is expected to become negatively tilted and centered from eastern MT southeastward through central NE/KS. Upstream of the trough axis, a belt of 50-60+ kt westerly mid-level flow is expected from northeastern AZ through the TX/OK Panhandles. Downward momentum mixing, in conjunction with a tightening surface pressure gradient and strong isallobaric flow, will yield persistent and strong surface flow around 20-30 mph during the afternoon and evening. Very dry conditions are also anticipated, with relative humidities as low as 5-10 percent. As a result, high confidence exists in critical meteorological fire-weather conditions across the delineated area. Locally extremely critical conditions are possible, but a few factors preclude highlighting a specific area, including: 1. local fuel state due to bands of wetting precipitation from thunderstorms on Saturday night and Sunday morning, and, 2. whether sustained surface winds will meet extremely critical conditions (30+ mph) for an extended period of time. Elevated/critical meteorological fire-weather conditions will likely develop to the northeast (e.g., southeastern CO and southwestern KS) and east (e.g., eastern TX/OK Panhandles) of the delineated areas as the dryline mixes eastward on Monday. However, much of these areas received around 0.5+ inches of precipitation recently, which should temper the fire-weather threat immediately behind the dryline. ..Flournoy.. 05/05/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0155 AM CDT Sun May 05 2024 Valid 061200Z - 071200Z ...CRITICAL FIRE WEATHER AREA FOR EASTERN NEW MEXICO INTO THE TEXAS AND OKLAHOMA PANHANDLES... ...Synopsis... An active fire-weather pattern will continue on D2/Monday as a powerful mid-level trough ejects through the Central Plains. Associated dry, windy conditions to the west of a dryline will lead to critical fire-weather conditions across central/eastern NM and the TX/OK Panhandles. By peak heating on Tuesday afternoon, the mid-level trough is expected to become negatively tilted and centered from eastern MT southeastward through central NE/KS. Upstream of the trough axis, a belt of 50-60+ kt westerly mid-level flow is expected from northeastern AZ through the TX/OK Panhandles. Downward momentum mixing, in conjunction with a tightening surface pressure gradient and strong isallobaric flow, will yield persistent and strong surface flow around 20-30 mph during the afternoon and evening. Very dry conditions are also anticipated, with relative humidities as low as 5-10 percent. As a result, high confidence exists in critical meteorological fire-weather conditions across the delineated area. Locally extremely critical conditions are possible, but a few factors preclude highlighting a specific area, including: 1. local fuel state due to bands of wetting precipitation from thunderstorms on Saturday night and Sunday morning, and, 2. whether sustained surface winds will meet extremely critical conditions (30+ mph) for an extended period of time. Elevated/critical meteorological fire-weather conditions will likely develop to the northeast (e.g., southeastern CO and southwestern KS) and east (e.g., eastern TX/OK Panhandles) of the delineated areas as the dryline mixes eastward on Monday. However, much of these areas received around 0.5+ inches of precipitation recently, which should temper the fire-weather threat immediately behind the dryline. ..Flournoy.. 05/05/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0155 AM CDT Sun May 05 2024 Valid 061200Z - 071200Z ...CRITICAL FIRE WEATHER AREA FOR EASTERN NEW MEXICO INTO THE TEXAS AND OKLAHOMA PANHANDLES... ...Synopsis... An active fire-weather pattern will continue on D2/Monday as a powerful mid-level trough ejects through the Central Plains. Associated dry, windy conditions to the west of a dryline will lead to critical fire-weather conditions across central/eastern NM and the TX/OK Panhandles. By peak heating on Tuesday afternoon, the mid-level trough is expected to become negatively tilted and centered from eastern MT southeastward through central NE/KS. Upstream of the trough axis, a belt of 50-60+ kt westerly mid-level flow is expected from northeastern AZ through the TX/OK Panhandles. Downward momentum mixing, in conjunction with a tightening surface pressure gradient and strong isallobaric flow, will yield persistent and strong surface flow around 20-30 mph during the afternoon and evening. Very dry conditions are also anticipated, with relative humidities as low as 5-10 percent. As a result, high confidence exists in critical meteorological fire-weather conditions across the delineated area. Locally extremely critical conditions are possible, but a few factors preclude highlighting a specific area, including: 1. local fuel state due to bands of wetting precipitation from thunderstorms on Saturday night and Sunday morning, and, 2. whether sustained surface winds will meet extremely critical conditions (30+ mph) for an extended period of time. Elevated/critical meteorological fire-weather conditions will likely develop to the northeast (e.g., southeastern CO and southwestern KS) and east (e.g., eastern TX/OK Panhandles) of the delineated areas as the dryline mixes eastward on Monday. However, much of these areas received around 0.5+ inches of precipitation recently, which should temper the fire-weather threat immediately behind the dryline. ..Flournoy.. 05/05/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0155 AM CDT Sun May 05 2024 Valid 061200Z - 071200Z ...CRITICAL FIRE WEATHER AREA FOR EASTERN NEW MEXICO INTO THE TEXAS AND OKLAHOMA PANHANDLES... ...Synopsis... An active fire-weather pattern will continue on D2/Monday as a powerful mid-level trough ejects through the Central Plains. Associated dry, windy conditions to the west of a dryline will lead to critical fire-weather conditions across central/eastern NM and the TX/OK Panhandles. By peak heating on Tuesday afternoon, the mid-level trough is expected to become negatively tilted and centered from eastern MT southeastward through central NE/KS. Upstream of the trough axis, a belt of 50-60+ kt westerly mid-level flow is expected from northeastern AZ through the TX/OK Panhandles. Downward momentum mixing, in conjunction with a tightening surface pressure gradient and strong isallobaric flow, will yield persistent and strong surface flow around 20-30 mph during the afternoon and evening. Very dry conditions are also anticipated, with relative humidities as low as 5-10 percent. As a result, high confidence exists in critical meteorological fire-weather conditions across the delineated area. Locally extremely critical conditions are possible, but a few factors preclude highlighting a specific area, including: 1. local fuel state due to bands of wetting precipitation from thunderstorms on Saturday night and Sunday morning, and, 2. whether sustained surface winds will meet extremely critical conditions (30+ mph) for an extended period of time. Elevated/critical meteorological fire-weather conditions will likely develop to the northeast (e.g., southeastern CO and southwestern KS) and east (e.g., eastern TX/OK Panhandles) of the delineated areas as the dryline mixes eastward on Monday. However, much of these areas received around 0.5+ inches of precipitation recently, which should temper the fire-weather threat immediately behind the dryline. ..Flournoy.. 05/05/2024 ...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 0105 AM CDT Sun May 05 2024 Valid 051200Z - 061200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF NEW MEXICO AND SOUTHEASTERN ARIZONA... ...Synopsis... Critical fire-weather conditions are expected later today across portions of the Desert Southwest, particularly from central/western NM into extreme southeastern AZ. Sustained surface winds around 20-25 mph and relative humidities approaching the single digits are forecast across the region, collocated with fuels supporting fire spread. These conditions will be present throughout the afternoon and evening across the delineated Critical and Elevated areas. The meteorological setup will be strongly influenced by a potent upper-level trough moving eastward toward the Desert Southwest today. The associated surface cyclone -- expected to deepen in the northern Rockies -- will yield strong westerly surface flow across AZ/NM. Despite some possible upper-level cloud cover, deep boundary-layer mixing and drying are anticipated. Surface relative humidities around 10-15 percent, and perhaps in the single digits in some locations, are expected by mid-afternoon. These dry and windy conditions are anticipated across a region with fuels supporting large-fire spread (e.g., ERCs generally around 70 percent or greater, increasing with southward extent). These critical fire-weather conditions are anticipated from mid-afternoon until sunset, particularly from around Albuquerque south-southwest to the Chiricahua Mountains. ..Flournoy.. 05/05/2024 ...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 0105 AM CDT Sun May 05 2024 Valid 051200Z - 061200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF NEW MEXICO AND SOUTHEASTERN ARIZONA... ...Synopsis... Critical fire-weather conditions are expected later today across portions of the Desert Southwest, particularly from central/western NM into extreme southeastern AZ. Sustained surface winds around 20-25 mph and relative humidities approaching the single digits are forecast across the region, collocated with fuels supporting fire spread. These conditions will be present throughout the afternoon and evening across the delineated Critical and Elevated areas. The meteorological setup will be strongly influenced by a potent upper-level trough moving eastward toward the Desert Southwest today. The associated surface cyclone -- expected to deepen in the northern Rockies -- will yield strong westerly surface flow across AZ/NM. Despite some possible upper-level cloud cover, deep boundary-layer mixing and drying are anticipated. Surface relative humidities around 10-15 percent, and perhaps in the single digits in some locations, are expected by mid-afternoon. These dry and windy conditions are anticipated across a region with fuels supporting large-fire spread (e.g., ERCs generally around 70 percent or greater, increasing with southward extent). These critical fire-weather conditions are anticipated from mid-afternoon until sunset, particularly from around Albuquerque south-southwest to the Chiricahua Mountains. ..Flournoy.. 05/05/2024 ...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 0105 AM CDT Sun May 05 2024 Valid 051200Z - 061200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF NEW MEXICO AND SOUTHEASTERN ARIZONA... ...Synopsis... Critical fire-weather conditions are expected later today across portions of the Desert Southwest, particularly from central/western NM into extreme southeastern AZ. Sustained surface winds around 20-25 mph and relative humidities approaching the single digits are forecast across the region, collocated with fuels supporting fire spread. These conditions will be present throughout the afternoon and evening across the delineated Critical and Elevated areas. The meteorological setup will be strongly influenced by a potent upper-level trough moving eastward toward the Desert Southwest today. The associated surface cyclone -- expected to deepen in the northern Rockies -- will yield strong westerly surface flow across AZ/NM. Despite some possible upper-level cloud cover, deep boundary-layer mixing and drying are anticipated. Surface relative humidities around 10-15 percent, and perhaps in the single digits in some locations, are expected by mid-afternoon. These dry and windy conditions are anticipated across a region with fuels supporting large-fire spread (e.g., ERCs generally around 70 percent or greater, increasing with southward extent). These critical fire-weather conditions are anticipated from mid-afternoon until sunset, particularly from around Albuquerque south-southwest to the Chiricahua Mountains. ..Flournoy.. 05/05/2024 ...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 0105 AM CDT Sun May 05 2024 Valid 051200Z - 061200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF NEW MEXICO AND SOUTHEASTERN ARIZONA... ...Synopsis... Critical fire-weather conditions are expected later today across portions of the Desert Southwest, particularly from central/western NM into extreme southeastern AZ. Sustained surface winds around 20-25 mph and relative humidities approaching the single digits are forecast across the region, collocated with fuels supporting fire spread. These conditions will be present throughout the afternoon and evening across the delineated Critical and Elevated areas. The meteorological setup will be strongly influenced by a potent upper-level trough moving eastward toward the Desert Southwest today. The associated surface cyclone -- expected to deepen in the northern Rockies -- will yield strong westerly surface flow across AZ/NM. Despite some possible upper-level cloud cover, deep boundary-layer mixing and drying are anticipated. Surface relative humidities around 10-15 percent, and perhaps in the single digits in some locations, are expected by mid-afternoon. These dry and windy conditions are anticipated across a region with fuels supporting large-fire spread (e.g., ERCs generally around 70 percent or greater, increasing with southward extent). These critical fire-weather conditions are anticipated from mid-afternoon until sunset, particularly from around Albuquerque south-southwest to the Chiricahua Mountains. ..Flournoy.. 05/05/2024 ...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 0105 AM CDT Sun May 05 2024 Valid 051200Z - 061200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF NEW MEXICO AND SOUTHEASTERN ARIZONA... ...Synopsis... Critical fire-weather conditions are expected later today across portions of the Desert Southwest, particularly from central/western NM into extreme southeastern AZ. Sustained surface winds around 20-25 mph and relative humidities approaching the single digits are forecast across the region, collocated with fuels supporting fire spread. These conditions will be present throughout the afternoon and evening across the delineated Critical and Elevated areas. The meteorological setup will be strongly influenced by a potent upper-level trough moving eastward toward the Desert Southwest today. The associated surface cyclone -- expected to deepen in the northern Rockies -- will yield strong westerly surface flow across AZ/NM. Despite some possible upper-level cloud cover, deep boundary-layer mixing and drying are anticipated. Surface relative humidities around 10-15 percent, and perhaps in the single digits in some locations, are expected by mid-afternoon. These dry and windy conditions are anticipated across a region with fuels supporting large-fire spread (e.g., ERCs generally around 70 percent or greater, increasing with southward extent). These critical fire-weather conditions are anticipated from mid-afternoon until sunset, particularly from around Albuquerque south-southwest to the Chiricahua Mountains. ..Flournoy.. 05/05/2024 ...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 0100 AM CDT Sun May 05 2024 Valid 061200Z - 071200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF WESTERN/CENTRAL OKLAHOMA AND SOUTH-CENTRAL KANSAS... ...SUMMARY... Numerous severe thunderstorms are expected to develop and move eastward Monday afternoon through Monday night across parts of the southern/central Plains. Multiple strong/potentially long-track tornadoes, very large to giant hail, and severe/damaging winds all appear likely. ...Synopsis... A negatively tilted upper trough with embedded 50-70 kt mid-level speed maximum will eject northeastward across the northern/central Plains on Monday. At the surface, the primary low will consolidate over the northern High Plains of eastern MT into western ND/SD and vicinity, with a secondary surface low forecast to develop over the central High Plains by Monday evening. A rather moist low-level airmass, with surface dewpoints generally in the mid 60s to low 70s, will spread northward across the southern/central Plains ahead of an eastward-mixing dryline and southeastward-moving cold front. A warm front should eventually reach eastward across parts of NE/IA. This warm front should be the northern limit of appreciable severe-thunderstorm potential through Monday night. ...Southern/Central Plains... Confidence has increased in a corridor of greater potential for strong tornadoes and very large hail, with multiple supercells likely to develop across south-central KS and western/central OK late Monday afternoon and continuing through much of the evening. Accordingly, a Moderate Risk has been introduced for this area. Daytime heating of the moist low-level airmass, coupled with steep mid-level lapse rates, will foster moderate to strong instability developing along/east of the dryline Monday afternoon. Peak pre-convective MLCAPE will likely reach 2500-4000 J/kg across much of central KS into western/central OK and northwest TX. Strong deep-layer shear of 40-50 kt will easily support supercells with initial thunderstorm development. Convective initiation appears likely by early Monday afternoon as ascent with the lead shortwave trough overspreads NE/KS. Very large hail will be a threat initially, but most guidance suggests a fairly quick transition to a more linear mode with time Monday afternoon/evening, especially as the cold front overtakes the dryline. An increasing threat for damaging winds and embedded tornadic circulations will likely occur as this mode transition occurs, in tandem with strengthening boundary-layer shear associated with a strengthening southerly low-level jet. This damaging-wind/tornado threat may continue into the overnight hours into parts of IA/MO, and the Slight Risk has been expanded eastward to account for this potential. Farther south across western OK and south-central KS, more modest large-scale ascent and related mid-level height falls associated with a more westerly mid/upper-level jet will eventually overspread the dryline and warm sector by late Monday afternoon. Although overall convective coverage will likely be lower compared to locations farther north, there should be a better chance for supercell structures to be maintained, as deep-layer shear vectors appear more orthogonal to the initiating boundary (dryline). A southerly low-level jet should strengthen to around 40-45 kt through early Monday evening across this area, greatly enhancing corresponding low-level shear and effective SRH. The best chance for strong, potentially long-track tornadoes and giant hail (3-4 inches) should exist with any supercells that can persist Monday evening in a very favorable thermodynamic and kinematic parameter space. Similar to locations farther north in KS/NE, upscale growth should eventually occur across central/eastern OK. A threat for damaging winds and tornadoes (some potentially strong) should continue Monday night into early Tuesday with eastward extent across the southern Plains given a sufficiently unstable and strongly sheared environment. ..Gleason.. 05/05/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Sun May 05 2024 Valid 061200Z - 071200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF WESTERN/CENTRAL OKLAHOMA AND SOUTH-CENTRAL KANSAS... ...SUMMARY... Numerous severe thunderstorms are expected to develop and move eastward Monday afternoon through Monday night across parts of the southern/central Plains. Multiple strong/potentially long-track tornadoes, very large to giant hail, and severe/damaging winds all appear likely. ...Synopsis... A negatively tilted upper trough with embedded 50-70 kt mid-level speed maximum will eject northeastward across the northern/central Plains on Monday. At the surface, the primary low will consolidate over the northern High Plains of eastern MT into western ND/SD and vicinity, with a secondary surface low forecast to develop over the central High Plains by Monday evening. A rather moist low-level airmass, with surface dewpoints generally in the mid 60s to low 70s, will spread northward across the southern/central Plains ahead of an eastward-mixing dryline and southeastward-moving cold front. A warm front should eventually reach eastward across parts of NE/IA. This warm front should be the northern limit of appreciable severe-thunderstorm potential through Monday night. ...Southern/Central Plains... Confidence has increased in a corridor of greater potential for strong tornadoes and very large hail, with multiple supercells likely to develop across south-central KS and western/central OK late Monday afternoon and continuing through much of the evening. Accordingly, a Moderate Risk has been introduced for this area. Daytime heating of the moist low-level airmass, coupled with steep mid-level lapse rates, will foster moderate to strong instability developing along/east of the dryline Monday afternoon. Peak pre-convective MLCAPE will likely reach 2500-4000 J/kg across much of central KS into western/central OK and northwest TX. Strong deep-layer shear of 40-50 kt will easily support supercells with initial thunderstorm development. Convective initiation appears likely by early Monday afternoon as ascent with the lead shortwave trough overspreads NE/KS. Very large hail will be a threat initially, but most guidance suggests a fairly quick transition to a more linear mode with time Monday afternoon/evening, especially as the cold front overtakes the dryline. An increasing threat for damaging winds and embedded tornadic circulations will likely occur as this mode transition occurs, in tandem with strengthening boundary-layer shear associated with a strengthening southerly low-level jet. This damaging-wind/tornado threat may continue into the overnight hours into parts of IA/MO, and the Slight Risk has been expanded eastward to account for this potential. Farther south across western OK and south-central KS, more modest large-scale ascent and related mid-level height falls associated with a more westerly mid/upper-level jet will eventually overspread the dryline and warm sector by late Monday afternoon. Although overall convective coverage will likely be lower compared to locations farther north, there should be a better chance for supercell structures to be maintained, as deep-layer shear vectors appear more orthogonal to the initiating boundary (dryline). A southerly low-level jet should strengthen to around 40-45 kt through early Monday evening across this area, greatly enhancing corresponding low-level shear and effective SRH. The best chance for strong, potentially long-track tornadoes and giant hail (3-4 inches) should exist with any supercells that can persist Monday evening in a very favorable thermodynamic and kinematic parameter space. Similar to locations farther north in KS/NE, upscale growth should eventually occur across central/eastern OK. A threat for damaging winds and tornadoes (some potentially strong) should continue Monday night into early Tuesday with eastward extent across the southern Plains given a sufficiently unstable and strongly sheared environment. ..Gleason.. 05/05/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Sun May 05 2024 Valid 061200Z - 071200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF WESTERN/CENTRAL OKLAHOMA AND SOUTH-CENTRAL KANSAS... ...SUMMARY... Numerous severe thunderstorms are expected to develop and move eastward Monday afternoon through Monday night across parts of the southern/central Plains. Multiple strong/potentially long-track tornadoes, very large to giant hail, and severe/damaging winds all appear likely. ...Synopsis... A negatively tilted upper trough with embedded 50-70 kt mid-level speed maximum will eject northeastward across the northern/central Plains on Monday. At the surface, the primary low will consolidate over the northern High Plains of eastern MT into western ND/SD and vicinity, with a secondary surface low forecast to develop over the central High Plains by Monday evening. A rather moist low-level airmass, with surface dewpoints generally in the mid 60s to low 70s, will spread northward across the southern/central Plains ahead of an eastward-mixing dryline and southeastward-moving cold front. A warm front should eventually reach eastward across parts of NE/IA. This warm front should be the northern limit of appreciable severe-thunderstorm potential through Monday night. ...Southern/Central Plains... Confidence has increased in a corridor of greater potential for strong tornadoes and very large hail, with multiple supercells likely to develop across south-central KS and western/central OK late Monday afternoon and continuing through much of the evening. Accordingly, a Moderate Risk has been introduced for this area. Daytime heating of the moist low-level airmass, coupled with steep mid-level lapse rates, will foster moderate to strong instability developing along/east of the dryline Monday afternoon. Peak pre-convective MLCAPE will likely reach 2500-4000 J/kg across much of central KS into western/central OK and northwest TX. Strong deep-layer shear of 40-50 kt will easily support supercells with initial thunderstorm development. Convective initiation appears likely by early Monday afternoon as ascent with the lead shortwave trough overspreads NE/KS. Very large hail will be a threat initially, but most guidance suggests a fairly quick transition to a more linear mode with time Monday afternoon/evening, especially as the cold front overtakes the dryline. An increasing threat for damaging winds and embedded tornadic circulations will likely occur as this mode transition occurs, in tandem with strengthening boundary-layer shear associated with a strengthening southerly low-level jet. This damaging-wind/tornado threat may continue into the overnight hours into parts of IA/MO, and the Slight Risk has been expanded eastward to account for this potential. Farther south across western OK and south-central KS, more modest large-scale ascent and related mid-level height falls associated with a more westerly mid/upper-level jet will eventually overspread the dryline and warm sector by late Monday afternoon. Although overall convective coverage will likely be lower compared to locations farther north, there should be a better chance for supercell structures to be maintained, as deep-layer shear vectors appear more orthogonal to the initiating boundary (dryline). A southerly low-level jet should strengthen to around 40-45 kt through early Monday evening across this area, greatly enhancing corresponding low-level shear and effective SRH. The best chance for strong, potentially long-track tornadoes and giant hail (3-4 inches) should exist with any supercells that can persist Monday evening in a very favorable thermodynamic and kinematic parameter space. Similar to locations farther north in KS/NE, upscale growth should eventually occur across central/eastern OK. A threat for damaging winds and tornadoes (some potentially strong) should continue Monday night into early Tuesday with eastward extent across the southern Plains given a sufficiently unstable and strongly sheared environment. ..Gleason.. 05/05/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Sun May 05 2024 Valid 061200Z - 071200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF WESTERN/CENTRAL OKLAHOMA AND SOUTH-CENTRAL KANSAS... ...SUMMARY... Numerous severe thunderstorms are expected to develop and move eastward Monday afternoon through Monday night across parts of the southern/central Plains. Multiple strong/potentially long-track tornadoes, very large to giant hail, and severe/damaging winds all appear likely. ...Synopsis... A negatively tilted upper trough with embedded 50-70 kt mid-level speed maximum will eject northeastward across the northern/central Plains on Monday. At the surface, the primary low will consolidate over the northern High Plains of eastern MT into western ND/SD and vicinity, with a secondary surface low forecast to develop over the central High Plains by Monday evening. A rather moist low-level airmass, with surface dewpoints generally in the mid 60s to low 70s, will spread northward across the southern/central Plains ahead of an eastward-mixing dryline and southeastward-moving cold front. A warm front should eventually reach eastward across parts of NE/IA. This warm front should be the northern limit of appreciable severe-thunderstorm potential through Monday night. ...Southern/Central Plains... Confidence has increased in a corridor of greater potential for strong tornadoes and very large hail, with multiple supercells likely to develop across south-central KS and western/central OK late Monday afternoon and continuing through much of the evening. Accordingly, a Moderate Risk has been introduced for this area. Daytime heating of the moist low-level airmass, coupled with steep mid-level lapse rates, will foster moderate to strong instability developing along/east of the dryline Monday afternoon. Peak pre-convective MLCAPE will likely reach 2500-4000 J/kg across much of central KS into western/central OK and northwest TX. Strong deep-layer shear of 40-50 kt will easily support supercells with initial thunderstorm development. Convective initiation appears likely by early Monday afternoon as ascent with the lead shortwave trough overspreads NE/KS. Very large hail will be a threat initially, but most guidance suggests a fairly quick transition to a more linear mode with time Monday afternoon/evening, especially as the cold front overtakes the dryline. An increasing threat for damaging winds and embedded tornadic circulations will likely occur as this mode transition occurs, in tandem with strengthening boundary-layer shear associated with a strengthening southerly low-level jet. This damaging-wind/tornado threat may continue into the overnight hours into parts of IA/MO, and the Slight Risk has been expanded eastward to account for this potential. Farther south across western OK and south-central KS, more modest large-scale ascent and related mid-level height falls associated with a more westerly mid/upper-level jet will eventually overspread the dryline and warm sector by late Monday afternoon. Although overall convective coverage will likely be lower compared to locations farther north, there should be a better chance for supercell structures to be maintained, as deep-layer shear vectors appear more orthogonal to the initiating boundary (dryline). A southerly low-level jet should strengthen to around 40-45 kt through early Monday evening across this area, greatly enhancing corresponding low-level shear and effective SRH. The best chance for strong, potentially long-track tornadoes and giant hail (3-4 inches) should exist with any supercells that can persist Monday evening in a very favorable thermodynamic and kinematic parameter space. Similar to locations farther north in KS/NE, upscale growth should eventually occur across central/eastern OK. A threat for damaging winds and tornadoes (some potentially strong) should continue Monday night into early Tuesday with eastward extent across the southern Plains given a sufficiently unstable and strongly sheared environment. ..Gleason.. 05/05/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Sun May 05 2024 Valid 061200Z - 071200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF WESTERN/CENTRAL OKLAHOMA AND SOUTH-CENTRAL KANSAS... ...SUMMARY... Numerous severe thunderstorms are expected to develop and move eastward Monday afternoon through Monday night across parts of the southern/central Plains. Multiple strong/potentially long-track tornadoes, very large to giant hail, and severe/damaging winds all appear likely. ...Synopsis... A negatively tilted upper trough with embedded 50-70 kt mid-level speed maximum will eject northeastward across the northern/central Plains on Monday. At the surface, the primary low will consolidate over the northern High Plains of eastern MT into western ND/SD and vicinity, with a secondary surface low forecast to develop over the central High Plains by Monday evening. A rather moist low-level airmass, with surface dewpoints generally in the mid 60s to low 70s, will spread northward across the southern/central Plains ahead of an eastward-mixing dryline and southeastward-moving cold front. A warm front should eventually reach eastward across parts of NE/IA. This warm front should be the northern limit of appreciable severe-thunderstorm potential through Monday night. ...Southern/Central Plains... Confidence has increased in a corridor of greater potential for strong tornadoes and very large hail, with multiple supercells likely to develop across south-central KS and western/central OK late Monday afternoon and continuing through much of the evening. Accordingly, a Moderate Risk has been introduced for this area. Daytime heating of the moist low-level airmass, coupled with steep mid-level lapse rates, will foster moderate to strong instability developing along/east of the dryline Monday afternoon. Peak pre-convective MLCAPE will likely reach 2500-4000 J/kg across much of central KS into western/central OK and northwest TX. Strong deep-layer shear of 40-50 kt will easily support supercells with initial thunderstorm development. Convective initiation appears likely by early Monday afternoon as ascent with the lead shortwave trough overspreads NE/KS. Very large hail will be a threat initially, but most guidance suggests a fairly quick transition to a more linear mode with time Monday afternoon/evening, especially as the cold front overtakes the dryline. An increasing threat for damaging winds and embedded tornadic circulations will likely occur as this mode transition occurs, in tandem with strengthening boundary-layer shear associated with a strengthening southerly low-level jet. This damaging-wind/tornado threat may continue into the overnight hours into parts of IA/MO, and the Slight Risk has been expanded eastward to account for this potential. Farther south across western OK and south-central KS, more modest large-scale ascent and related mid-level height falls associated with a more westerly mid/upper-level jet will eventually overspread the dryline and warm sector by late Monday afternoon. Although overall convective coverage will likely be lower compared to locations farther north, there should be a better chance for supercell structures to be maintained, as deep-layer shear vectors appear more orthogonal to the initiating boundary (dryline). A southerly low-level jet should strengthen to around 40-45 kt through early Monday evening across this area, greatly enhancing corresponding low-level shear and effective SRH. The best chance for strong, potentially long-track tornadoes and giant hail (3-4 inches) should exist with any supercells that can persist Monday evening in a very favorable thermodynamic and kinematic parameter space. Similar to locations farther north in KS/NE, upscale growth should eventually occur across central/eastern OK. A threat for damaging winds and tornadoes (some potentially strong) should continue Monday night into early Tuesday with eastward extent across the southern Plains given a sufficiently unstable and strongly sheared environment. ..Gleason.. 05/05/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1237 AM CDT Sun May 05 2024 Valid 051200Z - 061200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF SOUTH TEXAS... ...SUMMARY... Scattered strong to severe thunderstorms are possible across parts of South Texas today. A few strong, to locally severe, storms are also possible across the Mid-South and upper Ohio Valley. ...South TX to Mid-South... Southern Plains short-wave trough will progress into east TX by sunrise then eject across the Arklatex during the afternoon as a weakening 500mb speed max translates into the lower MS Valley. Low-level warm advection is not expected to be particularly strong ahead of this feature, but a modest LLJ will shift across the Arklatex into the middle TN Valley during the overnight hours. Early this morning, an expansive MCS has evolved ahead of the short wave over the southern Plains. This complex will propagate toward the lower Sabine River Valley then possibly weaken early in the period. Some airmass recovery is expected ahead of the MCS with modest heating expected from northern LA into northern MS by mid day. Of more concern is the trailing southwestern flank of the MCS across south-central TX. Early-day convection will likely extend across the TX Coastal Plain with more isolated activity farther west. However, convective outflow will sag south and serve as the focus for potential renewed robust convection later in the day. Surface temperatures should only warm through the 80s across deep south TX as east-southeasterly low-level flow will limit low-level lapse rates. However, the boundary may prove adequate for isolated supercells to develop within a sufficiently sheared environment for sustained rotating updrafts. Large hail and damaging winds would be the primary risk with the south TX activity. Isolated-scattered convection is expected to evolve across the Mid-South. While forecast lapse rates are poor, a few strong/severe storms could evolve ahead of the aforementioned short wave. Locally damaging winds and perhaps marginally severe hail are possible. ...Ohio Valley... Strong short-wave trough will advance across the upper Great Lakes into western QC by the end of the period. Southern influence of this feature will glance the upper OH Valley such that a few strong storms could evolve during the day. Surface front will be the primary focus for convective development, but forecast soundings show only modest surface-6km bulk shear, and do not exhibit particularly steep lapse rates (6-6.5 C/km). Gusty winds and marginally severe hail are the primary risks. ..Darrow/Flournoy.. 05/05/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1237 AM CDT Sun May 05 2024 Valid 051200Z - 061200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF SOUTH TEXAS... ...SUMMARY... Scattered strong to severe thunderstorms are possible across parts of South Texas today. A few strong, to locally severe, storms are also possible across the Mid-South and upper Ohio Valley. ...South TX to Mid-South... Southern Plains short-wave trough will progress into east TX by sunrise then eject across the Arklatex during the afternoon as a weakening 500mb speed max translates into the lower MS Valley. Low-level warm advection is not expected to be particularly strong ahead of this feature, but a modest LLJ will shift across the Arklatex into the middle TN Valley during the overnight hours. Early this morning, an expansive MCS has evolved ahead of the short wave over the southern Plains. This complex will propagate toward the lower Sabine River Valley then possibly weaken early in the period. Some airmass recovery is expected ahead of the MCS with modest heating expected from northern LA into northern MS by mid day. Of more concern is the trailing southwestern flank of the MCS across south-central TX. Early-day convection will likely extend across the TX Coastal Plain with more isolated activity farther west. However, convective outflow will sag south and serve as the focus for potential renewed robust convection later in the day. Surface temperatures should only warm through the 80s across deep south TX as east-southeasterly low-level flow will limit low-level lapse rates. However, the boundary may prove adequate for isolated supercells to develop within a sufficiently sheared environment for sustained rotating updrafts. Large hail and damaging winds would be the primary risk with the south TX activity. Isolated-scattered convection is expected to evolve across the Mid-South. While forecast lapse rates are poor, a few strong/severe storms could evolve ahead of the aforementioned short wave. Locally damaging winds and perhaps marginally severe hail are possible. ...Ohio Valley... Strong short-wave trough will advance across the upper Great Lakes into western QC by the end of the period. Southern influence of this feature will glance the upper OH Valley such that a few strong storms could evolve during the day. Surface front will be the primary focus for convective development, but forecast soundings show only modest surface-6km bulk shear, and do not exhibit particularly steep lapse rates (6-6.5 C/km). Gusty winds and marginally severe hail are the primary risks. ..Darrow/Flournoy.. 05/05/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1237 AM CDT Sun May 05 2024 Valid 051200Z - 061200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF SOUTH TEXAS... ...SUMMARY... Scattered strong to severe thunderstorms are possible across parts of South Texas today. A few strong, to locally severe, storms are also possible across the Mid-South and upper Ohio Valley. ...South TX to Mid-South... Southern Plains short-wave trough will progress into east TX by sunrise then eject across the Arklatex during the afternoon as a weakening 500mb speed max translates into the lower MS Valley. Low-level warm advection is not expected to be particularly strong ahead of this feature, but a modest LLJ will shift across the Arklatex into the middle TN Valley during the overnight hours. Early this morning, an expansive MCS has evolved ahead of the short wave over the southern Plains. This complex will propagate toward the lower Sabine River Valley then possibly weaken early in the period. Some airmass recovery is expected ahead of the MCS with modest heating expected from northern LA into northern MS by mid day. Of more concern is the trailing southwestern flank of the MCS across south-central TX. Early-day convection will likely extend across the TX Coastal Plain with more isolated activity farther west. However, convective outflow will sag south and serve as the focus for potential renewed robust convection later in the day. Surface temperatures should only warm through the 80s across deep south TX as east-southeasterly low-level flow will limit low-level lapse rates. However, the boundary may prove adequate for isolated supercells to develop within a sufficiently sheared environment for sustained rotating updrafts. Large hail and damaging winds would be the primary risk with the south TX activity. Isolated-scattered convection is expected to evolve across the Mid-South. While forecast lapse rates are poor, a few strong/severe storms could evolve ahead of the aforementioned short wave. Locally damaging winds and perhaps marginally severe hail are possible. ...Ohio Valley... Strong short-wave trough will advance across the upper Great Lakes into western QC by the end of the period. Southern influence of this feature will glance the upper OH Valley such that a few strong storms could evolve during the day. Surface front will be the primary focus for convective development, but forecast soundings show only modest surface-6km bulk shear, and do not exhibit particularly steep lapse rates (6-6.5 C/km). Gusty winds and marginally severe hail are the primary risks. ..Darrow/Flournoy.. 05/05/2024 Read more