Aggregator

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1152 PM CDT Sun Apr 21 2024 Valid 221200Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE SOUTHEAST FLORIDA PENINSULA... ...SUMMARY... Strong to locally severe thunderstorms, capable of marginally severe wind gusts and hail, will be possible across the southeast Florida Peninsula this afternoon. ...South Florida... An upper trough oriented from the Carolinas to the Southeast will shift east over the Atlantic waters by 00z. A belt of enhanced mid/upper westerly flow associated with the trough will overspread much of FL. At the surface, a cold front located over central FL will shift south through late afternoon. Ahead of the front, a moist airmass is already in place, with surface dewpoints in the upper 60s F. Modestly steep midlevel lapse rates atop this moist boundary-layer, coupled with daytime heating, will foster MLCAPE values to around 1000-1500 J/kg. The greatest instability will be focused near the southeast FL coast. Low-level flow will remain light and mainly parallel to the surface front, limiting convergence. Still, inhibition is forecast to be weak and thunderstorms are expected by afternoon near the surface front. Elongated hodographs, and around 35 kt effective shear magnitudes suggest supercells are possible. However, given weak forcing and possible strong outflows given steep low-level lapse rates beneath 850 mb, clustering may also be possible. Strongest convection will likely be confined to near the southeast FL coast. Locally strong/damaging gusts and perhaps marginally severe hail possible through late afternoon. ...Central Plains... An upper shortwave trough will migrate across the northern Plains, with height falls extending into the central Plains this afternoon/evening. A dearth of boundary-layer moisture is forecast in the wake of a cold frontal intrusion deep into the Gulf of Mexico and a large area of surface high pressure extending from the southern Plains to the Mid-South/TN Valley. Nevertheless, modest midlevel moisture is forecast over the region amid a plume of steep mid and low-level lapse rates. Minor elevated instability (generally 750 J/kg MUCAPE or less) is evident in forecast soundings above a warm layer around 700 mb. Some weak convection is expected and a few strong gusts or small hail is possible across southern NE into northern KS. However, longevity of stronger updrafts appears limited and coverage of convection is expected to be low, precluding marginal severe probabilities at this time. ..Leitman/Weinman.. 04/22/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1152 PM CDT Sun Apr 21 2024 Valid 221200Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE SOUTHEAST FLORIDA PENINSULA... ...SUMMARY... Strong to locally severe thunderstorms, capable of marginally severe wind gusts and hail, will be possible across the southeast Florida Peninsula this afternoon. ...South Florida... An upper trough oriented from the Carolinas to the Southeast will shift east over the Atlantic waters by 00z. A belt of enhanced mid/upper westerly flow associated with the trough will overspread much of FL. At the surface, a cold front located over central FL will shift south through late afternoon. Ahead of the front, a moist airmass is already in place, with surface dewpoints in the upper 60s F. Modestly steep midlevel lapse rates atop this moist boundary-layer, coupled with daytime heating, will foster MLCAPE values to around 1000-1500 J/kg. The greatest instability will be focused near the southeast FL coast. Low-level flow will remain light and mainly parallel to the surface front, limiting convergence. Still, inhibition is forecast to be weak and thunderstorms are expected by afternoon near the surface front. Elongated hodographs, and around 35 kt effective shear magnitudes suggest supercells are possible. However, given weak forcing and possible strong outflows given steep low-level lapse rates beneath 850 mb, clustering may also be possible. Strongest convection will likely be confined to near the southeast FL coast. Locally strong/damaging gusts and perhaps marginally severe hail possible through late afternoon. ...Central Plains... An upper shortwave trough will migrate across the northern Plains, with height falls extending into the central Plains this afternoon/evening. A dearth of boundary-layer moisture is forecast in the wake of a cold frontal intrusion deep into the Gulf of Mexico and a large area of surface high pressure extending from the southern Plains to the Mid-South/TN Valley. Nevertheless, modest midlevel moisture is forecast over the region amid a plume of steep mid and low-level lapse rates. Minor elevated instability (generally 750 J/kg MUCAPE or less) is evident in forecast soundings above a warm layer around 700 mb. Some weak convection is expected and a few strong gusts or small hail is possible across southern NE into northern KS. However, longevity of stronger updrafts appears limited and coverage of convection is expected to be low, precluding marginal severe probabilities at this time. ..Leitman/Weinman.. 04/22/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1152 PM CDT Sun Apr 21 2024 Valid 221200Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE SOUTHEAST FLORIDA PENINSULA... ...SUMMARY... Strong to locally severe thunderstorms, capable of marginally severe wind gusts and hail, will be possible across the southeast Florida Peninsula this afternoon. ...South Florida... An upper trough oriented from the Carolinas to the Southeast will shift east over the Atlantic waters by 00z. A belt of enhanced mid/upper westerly flow associated with the trough will overspread much of FL. At the surface, a cold front located over central FL will shift south through late afternoon. Ahead of the front, a moist airmass is already in place, with surface dewpoints in the upper 60s F. Modestly steep midlevel lapse rates atop this moist boundary-layer, coupled with daytime heating, will foster MLCAPE values to around 1000-1500 J/kg. The greatest instability will be focused near the southeast FL coast. Low-level flow will remain light and mainly parallel to the surface front, limiting convergence. Still, inhibition is forecast to be weak and thunderstorms are expected by afternoon near the surface front. Elongated hodographs, and around 35 kt effective shear magnitudes suggest supercells are possible. However, given weak forcing and possible strong outflows given steep low-level lapse rates beneath 850 mb, clustering may also be possible. Strongest convection will likely be confined to near the southeast FL coast. Locally strong/damaging gusts and perhaps marginally severe hail possible through late afternoon. ...Central Plains... An upper shortwave trough will migrate across the northern Plains, with height falls extending into the central Plains this afternoon/evening. A dearth of boundary-layer moisture is forecast in the wake of a cold frontal intrusion deep into the Gulf of Mexico and a large area of surface high pressure extending from the southern Plains to the Mid-South/TN Valley. Nevertheless, modest midlevel moisture is forecast over the region amid a plume of steep mid and low-level lapse rates. Minor elevated instability (generally 750 J/kg MUCAPE or less) is evident in forecast soundings above a warm layer around 700 mb. Some weak convection is expected and a few strong gusts or small hail is possible across southern NE into northern KS. However, longevity of stronger updrafts appears limited and coverage of convection is expected to be low, precluding marginal severe probabilities at this time. ..Leitman/Weinman.. 04/22/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1152 PM CDT Sun Apr 21 2024 Valid 221200Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE SOUTHEAST FLORIDA PENINSULA... ...SUMMARY... Strong to locally severe thunderstorms, capable of marginally severe wind gusts and hail, will be possible across the southeast Florida Peninsula this afternoon. ...South Florida... An upper trough oriented from the Carolinas to the Southeast will shift east over the Atlantic waters by 00z. A belt of enhanced mid/upper westerly flow associated with the trough will overspread much of FL. At the surface, a cold front located over central FL will shift south through late afternoon. Ahead of the front, a moist airmass is already in place, with surface dewpoints in the upper 60s F. Modestly steep midlevel lapse rates atop this moist boundary-layer, coupled with daytime heating, will foster MLCAPE values to around 1000-1500 J/kg. The greatest instability will be focused near the southeast FL coast. Low-level flow will remain light and mainly parallel to the surface front, limiting convergence. Still, inhibition is forecast to be weak and thunderstorms are expected by afternoon near the surface front. Elongated hodographs, and around 35 kt effective shear magnitudes suggest supercells are possible. However, given weak forcing and possible strong outflows given steep low-level lapse rates beneath 850 mb, clustering may also be possible. Strongest convection will likely be confined to near the southeast FL coast. Locally strong/damaging gusts and perhaps marginally severe hail possible through late afternoon. ...Central Plains... An upper shortwave trough will migrate across the northern Plains, with height falls extending into the central Plains this afternoon/evening. A dearth of boundary-layer moisture is forecast in the wake of a cold frontal intrusion deep into the Gulf of Mexico and a large area of surface high pressure extending from the southern Plains to the Mid-South/TN Valley. Nevertheless, modest midlevel moisture is forecast over the region amid a plume of steep mid and low-level lapse rates. Minor elevated instability (generally 750 J/kg MUCAPE or less) is evident in forecast soundings above a warm layer around 700 mb. Some weak convection is expected and a few strong gusts or small hail is possible across southern NE into northern KS. However, longevity of stronger updrafts appears limited and coverage of convection is expected to be low, precluding marginal severe probabilities at this time. ..Leitman/Weinman.. 04/22/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0740 PM CDT Sun Apr 21 2024 Valid 220100Z - 221200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorm potential will remain low through tonight. ...Southeast GA/North FL... Severe probabilities have been removed from southeast GA/northern FL with the 01z update. Weakening large-scale ascent, poor low-level convergence, and a cooling/stabilizing boundary layer post-sunset will suppress severe thunderstorm potential the remainder of the evening. However, sufficient elevated instability may support isolated non-severe thunderstorm near the southward sagging surface front for a few more hours. ..Leitman.. 04/22/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0740 PM CDT Sun Apr 21 2024 Valid 220100Z - 221200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorm potential will remain low through tonight. ...Southeast GA/North FL... Severe probabilities have been removed from southeast GA/northern FL with the 01z update. Weakening large-scale ascent, poor low-level convergence, and a cooling/stabilizing boundary layer post-sunset will suppress severe thunderstorm potential the remainder of the evening. However, sufficient elevated instability may support isolated non-severe thunderstorm near the southward sagging surface front for a few more hours. ..Leitman.. 04/22/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0740 PM CDT Sun Apr 21 2024 Valid 220100Z - 221200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorm potential will remain low through tonight. ...Southeast GA/North FL... Severe probabilities have been removed from southeast GA/northern FL with the 01z update. Weakening large-scale ascent, poor low-level convergence, and a cooling/stabilizing boundary layer post-sunset will suppress severe thunderstorm potential the remainder of the evening. However, sufficient elevated instability may support isolated non-severe thunderstorm near the southward sagging surface front for a few more hours. ..Leitman.. 04/22/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0740 PM CDT Sun Apr 21 2024 Valid 220100Z - 221200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorm potential will remain low through tonight. ...Southeast GA/North FL... Severe probabilities have been removed from southeast GA/northern FL with the 01z update. Weakening large-scale ascent, poor low-level convergence, and a cooling/stabilizing boundary layer post-sunset will suppress severe thunderstorm potential the remainder of the evening. However, sufficient elevated instability may support isolated non-severe thunderstorm near the southward sagging surface front for a few more hours. ..Leitman.. 04/22/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0740 PM CDT Sun Apr 21 2024 Valid 220100Z - 221200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorm potential will remain low through tonight. ...Southeast GA/North FL... Severe probabilities have been removed from southeast GA/northern FL with the 01z update. Weakening large-scale ascent, poor low-level convergence, and a cooling/stabilizing boundary layer post-sunset will suppress severe thunderstorm potential the remainder of the evening. However, sufficient elevated instability may support isolated non-severe thunderstorm near the southward sagging surface front for a few more hours. ..Leitman.. 04/22/2024 Read more

No watches are valid as of Sun Apr 21 22:17:02 UTC 2024.

No Mesoscale Discussions are in effect as of Sun Apr 21 22:17:02 UTC 2024.

MD 0504 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR SOUTHEAST GA...FAR NORTHEAST FL
Mesoscale Discussion 0504 NWS Storm Prediction Center Norman OK 0245 PM CDT Sun Apr 21 2024 Areas affected...Southeast GA...Far Northeast FL Concerning...Severe potential...Watch unlikely Valid 211945Z - 212145Z Probability of Watch Issuance...20 percent SUMMARY...Ongoing convective line may produce isolated damaging gusts from 45 to 60 mph as it continue eastward across southeast Georgia and far northeast Florida. DISCUSSION...Recent regional radar imagery has shown an increase in intensity of the convective line that extends from extreme southern SC southwestward across southeast GA, just ahead of a southeastward-progressing cold front. Modest buoyancy exists downstream of this line, supported by surface temperatures in the upper 70s and dewpoints in the mid 60s. Additionally, a shortwave trough is moving quickly across the Southeast, contributing to increasing large-scale ascent and deep-layer vertical shear across the region. These factors are expected to result in maintenance, or perhaps even some modest strengthening, of the ongoing line as it moves eastward. Primary threat from this line is isolated damaging gusts from 45 to 60 mph. Limited spatial extent and intensity of this threat is expected to preclude the need for a watch. ..Mosier/Smith.. 04/21/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...CHS...JAX...FFC...TAE... LAT...LON 31608254 32278187 32488103 32208068 31818100 31468115 31058131 30358141 30298227 30608344 31608254 Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0414 PM CDT Sun Apr 21 2024 Valid 231200Z - 291200Z Upper-level ridging over the Plains will promote relatively quiescent fire weather conditions during the middle of the week. By Thursday into the weekend though, a series of mid-level troughs will eject into the southern Plains, supporting the development of multiple surface cyclones and accompanying eastward surges of a dryline over the southern High Plains each day. In the post-dryline environment, Critical overlapping surface westerly winds and RH are expected, with guidance consensus showing the best chance at such conditions occurring along the CO/KS/TX/NM border areas by Thursday-Saturday afternoon peak heating. Here, 70 percent critical probabilities have been introduced for Days 5-7 (Thursday-Saturday), though Critical fire weather concerns may persist into early next week. Higher Critical probabilities may be needed for Sunday and perhaps beyond over the southern High Plains if guidance consensus shows the continued critically dry and windy conditions with any consistency. ..Squitieri.. 04/21/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0414 PM CDT Sun Apr 21 2024 Valid 231200Z - 291200Z Upper-level ridging over the Plains will promote relatively quiescent fire weather conditions during the middle of the week. By Thursday into the weekend though, a series of mid-level troughs will eject into the southern Plains, supporting the development of multiple surface cyclones and accompanying eastward surges of a dryline over the southern High Plains each day. In the post-dryline environment, Critical overlapping surface westerly winds and RH are expected, with guidance consensus showing the best chance at such conditions occurring along the CO/KS/TX/NM border areas by Thursday-Saturday afternoon peak heating. Here, 70 percent critical probabilities have been introduced for Days 5-7 (Thursday-Saturday), though Critical fire weather concerns may persist into early next week. Higher Critical probabilities may be needed for Sunday and perhaps beyond over the southern High Plains if guidance consensus shows the continued critically dry and windy conditions with any consistency. ..Squitieri.. 04/21/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0414 PM CDT Sun Apr 21 2024 Valid 231200Z - 291200Z Upper-level ridging over the Plains will promote relatively quiescent fire weather conditions during the middle of the week. By Thursday into the weekend though, a series of mid-level troughs will eject into the southern Plains, supporting the development of multiple surface cyclones and accompanying eastward surges of a dryline over the southern High Plains each day. In the post-dryline environment, Critical overlapping surface westerly winds and RH are expected, with guidance consensus showing the best chance at such conditions occurring along the CO/KS/TX/NM border areas by Thursday-Saturday afternoon peak heating. Here, 70 percent critical probabilities have been introduced for Days 5-7 (Thursday-Saturday), though Critical fire weather concerns may persist into early next week. Higher Critical probabilities may be needed for Sunday and perhaps beyond over the southern High Plains if guidance consensus shows the continued critically dry and windy conditions with any consistency. ..Squitieri.. 04/21/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0414 PM CDT Sun Apr 21 2024 Valid 231200Z - 291200Z Upper-level ridging over the Plains will promote relatively quiescent fire weather conditions during the middle of the week. By Thursday into the weekend though, a series of mid-level troughs will eject into the southern Plains, supporting the development of multiple surface cyclones and accompanying eastward surges of a dryline over the southern High Plains each day. In the post-dryline environment, Critical overlapping surface westerly winds and RH are expected, with guidance consensus showing the best chance at such conditions occurring along the CO/KS/TX/NM border areas by Thursday-Saturday afternoon peak heating. Here, 70 percent critical probabilities have been introduced for Days 5-7 (Thursday-Saturday), though Critical fire weather concerns may persist into early next week. Higher Critical probabilities may be needed for Sunday and perhaps beyond over the southern High Plains if guidance consensus shows the continued critically dry and windy conditions with any consistency. ..Squitieri.. 04/21/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0414 PM CDT Sun Apr 21 2024 Valid 231200Z - 291200Z Upper-level ridging over the Plains will promote relatively quiescent fire weather conditions during the middle of the week. By Thursday into the weekend though, a series of mid-level troughs will eject into the southern Plains, supporting the development of multiple surface cyclones and accompanying eastward surges of a dryline over the southern High Plains each day. In the post-dryline environment, Critical overlapping surface westerly winds and RH are expected, with guidance consensus showing the best chance at such conditions occurring along the CO/KS/TX/NM border areas by Thursday-Saturday afternoon peak heating. Here, 70 percent critical probabilities have been introduced for Days 5-7 (Thursday-Saturday), though Critical fire weather concerns may persist into early next week. Higher Critical probabilities may be needed for Sunday and perhaps beyond over the southern High Plains if guidance consensus shows the continued critically dry and windy conditions with any consistency. ..Squitieri.. 04/21/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0414 PM CDT Sun Apr 21 2024 Valid 231200Z - 291200Z Upper-level ridging over the Plains will promote relatively quiescent fire weather conditions during the middle of the week. By Thursday into the weekend though, a series of mid-level troughs will eject into the southern Plains, supporting the development of multiple surface cyclones and accompanying eastward surges of a dryline over the southern High Plains each day. In the post-dryline environment, Critical overlapping surface westerly winds and RH are expected, with guidance consensus showing the best chance at such conditions occurring along the CO/KS/TX/NM border areas by Thursday-Saturday afternoon peak heating. Here, 70 percent critical probabilities have been introduced for Days 5-7 (Thursday-Saturday), though Critical fire weather concerns may persist into early next week. Higher Critical probabilities may be needed for Sunday and perhaps beyond over the southern High Plains if guidance consensus shows the continued critically dry and windy conditions with any consistency. ..Squitieri.. 04/21/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0414 PM CDT Sun Apr 21 2024 Valid 231200Z - 291200Z Upper-level ridging over the Plains will promote relatively quiescent fire weather conditions during the middle of the week. By Thursday into the weekend though, a series of mid-level troughs will eject into the southern Plains, supporting the development of multiple surface cyclones and accompanying eastward surges of a dryline over the southern High Plains each day. In the post-dryline environment, Critical overlapping surface westerly winds and RH are expected, with guidance consensus showing the best chance at such conditions occurring along the CO/KS/TX/NM border areas by Thursday-Saturday afternoon peak heating. Here, 70 percent critical probabilities have been introduced for Days 5-7 (Thursday-Saturday), though Critical fire weather concerns may persist into early next week. Higher Critical probabilities may be needed for Sunday and perhaps beyond over the southern High Plains if guidance consensus shows the continued critically dry and windy conditions with any consistency. ..Squitieri.. 04/21/2024 ...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 0251 PM CDT Sun Apr 21 2024 Valid 221200Z - 231200Z ...NO CRITICAL AREAS... The previous forecast remains on track. Guidance consensus continues to show solidly Elevated equivalent winds and RH to overspread portions of the northern High Plains tomorrow afternoon. Still, fuels appear too poorly receptive to support significant wildfire spread, with fire weather highlights withheld this outlook. A dry thunderstorm or two may also occur along portions of the central High Plains tomorrow afternoon, where fuels are at least modestly receptive to wildfire spread. However, confidence in storm coverage to prompt more than a localized wildfire-spread threat via lightning-induced ignitions is too low to introduce isolated dry thunderstorm highlights at this time. ..Squitieri.. 04/21/2024 .PREV DISCUSSION... /ISSUED 0154 AM CDT Sun Apr 21 2024/ ...Synopsis... Along the southern periphery of a midlevel low tracking eastward across southern Canada, a swath of strong deep-layer westerly flow will overspread the northern/central Plains into the Upper MS Valley. At the same time, a cold front will move eastward across the region. Behind the front, 20-30 mph sustained west-northwesterly surface winds (with higher gusts) will overlap the northern edge of low boundary-layer RH across eastern MT into the Dakotas. While this may lead to localized fire-weather concerns, preceding rainfall atop already marginal fuels for some areas, and uncertainty regarding RH reductions, limit confidence in the fire-weather threat -- precluding Elevated highlights at this time. Ahead of the front from the southern Plains into the Midwest, a tight pressure gradient beneath a strong low-level jet will yield 20-25 mph sustained southwesterly surface winds (with gusts upwards of 35 mph). However, RH reductions generally appear marginal across this corridor. Nevertheless, the strong/gusty winds may still promote locally elevated fire-weather conditions where fuels are receptive to fire spread. ...Please see www.spc.noaa.gov/fire for graphic product... Read more