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SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0215 PM CDT Sun Apr 30 2023 Valid 011200Z - 021200Z No changes are needed to the D2 Fire Weather Outlook. See previous discussion below. ..Thornton.. 04/30/2023 .PREV DISCUSSION... /ISSUED 0153 AM CDT Sun Apr 30 2023/ ...Synopsis... As ridging builds over the Rockies and Great Basin with the aforementioned omega block, stronger southwesterly flow aloft will begin to develop across portions of the Southwest on the fringes of an upper low off the West Coast. A deepening surface low over the Great Basin will enhance southerly winds across portions of southern AZ and NM. Here, warm and dry surface conditions are also expected with afternoon RH values below 15% possible. With wind speeds of 15-20 mph overlapping low humidity and somewhat receptive fuels, a few hours of Elevated fire-weather conditions appear likely Monday. The best overlap of drying fuels and windy/dry conditions will be possible across southern Arizona and far southwestern New Mexico, where ERCs are approaching the 75th percentile with poor overnight recoveries expected. While favorable meteorological conditions will likely extended farther north, fuel conditions remain too prohibitive for highlights, given the early season. ...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 0215 PM CDT Sun Apr 30 2023 Valid 011200Z - 021200Z No changes are needed to the D2 Fire Weather Outlook. See previous discussion below. ..Thornton.. 04/30/2023 .PREV DISCUSSION... /ISSUED 0153 AM CDT Sun Apr 30 2023/ ...Synopsis... As ridging builds over the Rockies and Great Basin with the aforementioned omega block, stronger southwesterly flow aloft will begin to develop across portions of the Southwest on the fringes of an upper low off the West Coast. A deepening surface low over the Great Basin will enhance southerly winds across portions of southern AZ and NM. Here, warm and dry surface conditions are also expected with afternoon RH values below 15% possible. With wind speeds of 15-20 mph overlapping low humidity and somewhat receptive fuels, a few hours of Elevated fire-weather conditions appear likely Monday. The best overlap of drying fuels and windy/dry conditions will be possible across southern Arizona and far southwestern New Mexico, where ERCs are approaching the 75th percentile with poor overnight recoveries expected. While favorable meteorological conditions will likely extended farther north, fuel conditions remain too prohibitive for highlights, given the early season. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1211 PM CDT Sun Apr 30 2023 Valid 011200Z - 021200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The severe-thunderstorm threat is expected to be low on Monday. ...Synopsis... The upper-air pattern is forecast to evolve into an omega block as a mid-level low remains nearly stationary over the Great Lakes while a mid-level low migrates southward from near the Vancouver/WA coast to San Francisco Bay by early Tuesday morning. In between these two features, a mid-level ridge will reside over the Rockies/High Plains. In the low levels, surface high pressure will influence conditions across much of the Gulf Coast north-northwestward into the Upper Midwest. Low-topped convection in the form of scattered showers and perhaps a few thunderstorms are possible near the mid-level cold core over Upstate NY. Isolated thunderstorms are also likely to develop across the central Rockies and from eastern WA/ID southward through OR into northwest NV. Small hail perhaps could develop where buoyancy is greatest during the afternoon in western ID and near the Sangre de Cristos, but storm intensity is not expected to reach severe limits. ..Smith.. 04/30/2023 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1211 PM CDT Sun Apr 30 2023 Valid 011200Z - 021200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The severe-thunderstorm threat is expected to be low on Monday. ...Synopsis... The upper-air pattern is forecast to evolve into an omega block as a mid-level low remains nearly stationary over the Great Lakes while a mid-level low migrates southward from near the Vancouver/WA coast to San Francisco Bay by early Tuesday morning. In between these two features, a mid-level ridge will reside over the Rockies/High Plains. In the low levels, surface high pressure will influence conditions across much of the Gulf Coast north-northwestward into the Upper Midwest. Low-topped convection in the form of scattered showers and perhaps a few thunderstorms are possible near the mid-level cold core over Upstate NY. Isolated thunderstorms are also likely to develop across the central Rockies and from eastern WA/ID southward through OR into northwest NV. Small hail perhaps could develop where buoyancy is greatest during the afternoon in western ID and near the Sangre de Cristos, but storm intensity is not expected to reach severe limits. ..Smith.. 04/30/2023 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1141 AM CDT Sun Apr 30 2023 Valid 301700Z - 011200Z No changes are needed to the D1 Fire Weather Outlook. See previous discussion below. ..Thornton.. 04/30/2023 .PREV DISCUSSION... /ISSUED 0151 AM CDT Sun Apr 30 2023/ ...Synopsis... An omega block with a broad mid-level cyclone will dominate the flow pattern for the eastern half of the country through the forecast period. Northwesterly flow aloft is expected over the Plains supporting dry and breezy conditions. Meanwhile, ridging and weaker winds are expected over portions of the Southwest and Rockies, while a cold front moves south. ...Central Plains... In the wake of a cold front moving south across the Plains, dry northwesterly flow is expected over portions of southern NE and northern KS. Surface winds gusting to near 20 mph will overlap with afternoon RH values of 20-25% for a few hours during peak heating. Occurring in a relative minimum of recent precipitation, area fuels are somewhat conducive to fire spread. A few hours of elevated to locally critical fire-weather conditions are possible through the afternoon. ...West TX and eastern NM... Ahead of the surface cold front, westerly downslope winds are expected through the day across portions of eastern NM and west TX. While not overly strong, occasional gusts near 15-20 mph will likely overlap with surface humidity values below 20%. A few hours of locally elevated fire-weather conditions are possible within the dry fuels. However, confidence in spatial coverage is low owing to the modest surface winds. ...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 1141 AM CDT Sun Apr 30 2023 Valid 301700Z - 011200Z No changes are needed to the D1 Fire Weather Outlook. See previous discussion below. ..Thornton.. 04/30/2023 .PREV DISCUSSION... /ISSUED 0151 AM CDT Sun Apr 30 2023/ ...Synopsis... An omega block with a broad mid-level cyclone will dominate the flow pattern for the eastern half of the country through the forecast period. Northwesterly flow aloft is expected over the Plains supporting dry and breezy conditions. Meanwhile, ridging and weaker winds are expected over portions of the Southwest and Rockies, while a cold front moves south. ...Central Plains... In the wake of a cold front moving south across the Plains, dry northwesterly flow is expected over portions of southern NE and northern KS. Surface winds gusting to near 20 mph will overlap with afternoon RH values of 20-25% for a few hours during peak heating. Occurring in a relative minimum of recent precipitation, area fuels are somewhat conducive to fire spread. A few hours of elevated to locally critical fire-weather conditions are possible through the afternoon. ...West TX and eastern NM... Ahead of the surface cold front, westerly downslope winds are expected through the day across portions of eastern NM and west TX. While not overly strong, occasional gusts near 15-20 mph will likely overlap with surface humidity values below 20%. A few hours of locally elevated fire-weather conditions are possible within the dry fuels. However, confidence in spatial coverage is low owing to the modest surface winds. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1126 AM CDT Sun Apr 30 2023 Valid 301630Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON FROM NORTHEAST SC ACROSS EASTERN NC TO SOUTHEAST VA... ...SUMMARY... Isolated damaging thunderstorm winds and marginally severe hail will be possible this afternoon from northeast South Carolina to southeast Virginia. ...Northeast SC into eastern NC/southeast VA this afternoon... Around the southeast periphery of a deep low over Lake MI, a pronounced shortwave trough will eject quickly northeastward today across the Carolinas and Mid-Atlantic. An associated surface cyclone will likewise move northeastward and deepen from the Carolina Piedmont to the Mid-Atlantic by this evening, as a trailing cold front moves off the Southeast Atlantic Coast. Prior to frontal passage, there will be a window of opportunity for destabilization from northeast SC into eastern NC, in the wake of ongoing rain/clouds across eastern NC. Boundary-layer dewpoints in the mid-upper 60s, surface temperatures warming into the low-mid 70s, and cooling midlevel temperatures will result in MLCAPE of 1000-1500 J/kg and minimal convective inhibition this afternoon. Ongoing thunderstorms in SC along the front and on the nose of the midlevel dry slot will expand some in coverage while spreading northeastward into eastern NC/southeast VA this afternoon. These storms will pose a threat for wind damage and large hail, given the moderate buoyancy/cool midlevel temperatures and straight hodographs. ..Thompson/Squitieri.. 04/30/2023 Read more

Drought across Nebraska left the Missouri and Platte rivers at low flows, reducing the flood concern. However, dry conditions were causing problems for farmers. The Nebraska Farm Bureau president, who farms in Merrick County in the east central part of the state, noted that conditions were as dry as they have ever been this spring and thought that there may be too little soil moisture to germinate seed. While the subsoil held some moisture last year, this year it did not. The ground was too hard in some areas to get the planter in the ground. Omaha World-Herald (Neb.), April 29, 2023

No Mesoscale Discussions are in effect as of Sat Apr 29 21:30:05 UTC 2023.

WW 0183 Status Updates
STATUS REPORT ON WW 183 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 70 SSW CTY TO 25 S VLD. ..MOORE..04/29/23 ATTN...WFO...JAX...MLB...TBW...TAE... STATUS REPORT FOR WT 183 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS FLC001-007-009-017-019-027-029-035-041-049-053-055-057-061-069- 075-081-083-085-093-095-097-101-103-105-107-109-111-115-117-119- 125-127-292140- FL . FLORIDA COUNTIES INCLUDED ARE ALACHUA BRADFORD BREVARD CITRUS CLAY DESOTO DIXIE FLAGLER GILCHRIST HARDEE HERNANDO HIGHLANDS HILLSBOROUGH INDIAN RIVER LAKE LEVY MANATEE MARION MARTIN OKEECHOBEE ORANGE OSCEOLA PASCO PINELLAS POLK PUTNAM ST. JOHNS ST. LUCIE SARASOTA SEMINOLE SUMTER UNION VOLUSIA AMZ454-550-552-555-GMZ830-850-853-292140- CW . ADJACENT COASTAL WATERS INCLUDED ARE Read more

WW 0183 Status Updates
STATUS REPORT ON WW 183 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 70 SSW CTY TO 25 S VLD. ..MOORE..04/29/23 ATTN...WFO...JAX...MLB...TBW...TAE... STATUS REPORT FOR WT 183 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS FLC001-007-009-017-019-027-029-035-041-049-053-055-057-061-069- 075-081-083-085-093-095-097-101-103-105-107-109-111-115-117-119- 125-127-292140- FL . FLORIDA COUNTIES INCLUDED ARE ALACHUA BRADFORD BREVARD CITRUS CLAY DESOTO DIXIE FLAGLER GILCHRIST HARDEE HERNANDO HIGHLANDS HILLSBOROUGH INDIAN RIVER LAKE LEVY MANATEE MARION MARTIN OKEECHOBEE ORANGE OSCEOLA PASCO PINELLAS POLK PUTNAM ST. JOHNS ST. LUCIE SARASOTA SEMINOLE SUMTER UNION VOLUSIA AMZ454-550-552-555-GMZ830-850-853-292140- CW . ADJACENT COASTAL WATERS INCLUDED ARE Read more

WW 183 TORNADO FL CW 291940Z - 300200Z
URGENT - IMMEDIATE BROADCAST REQUESTED Tornado Watch Number 183 NWS Storm Prediction Center Norman OK 340 PM EDT Sat Apr 29 2023 The NWS Storm Prediction Center has issued a * Tornado Watch for portions of Central and north Florida Coastal Waters * Effective this Saturday afternoon and evening from 340 PM until 1000 PM EDT. * Primary threats include... A couple tornadoes possible Scattered damaging wind gusts to 70 mph possible Isolated large hail events to 1.5 inches in diameter possible SUMMARY...Isolated severe storms will remain possible this afternoon close to the Atlantic coast with the sea breeze, and a larger cluster of storms will move inland from the northeast Gulf of Mexico later this afternoon. The initial storms near the Atlantic coast will pose a threat for isolated large hail/damaging gusts, while the Gulf storms moving inland will pose the threat for damaging winds. A couple of tornadoes will also be possible with storm interactions and embedded circulations. The tornado watch area is approximately along and 70 statute miles east and west of a line from 30 miles north of Gainesville FL to 40 miles south southwest of Avon Park FL. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU3). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Tornado Watch means conditions are favorable for tornadoes and severe thunderstorms in and close to the watch area. Persons in these areas should be on the lookout for threatening weather conditions and listen for later statements and possible warnings. && AVIATION...Tornadoes and a few severe thunderstorms with hail surface and aloft to 1.5 inches. Extreme turbulence and surface wind gusts to 60 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 26035. ...Thompson Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0259 PM CDT Sat Apr 29 2023 Valid 292000Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTION OF THE CENTRAL FLORIDA PENINSULA... ...SUMMARY... Two rounds of severe thunderstorms, with damaging winds, large hail, and a coup[e of tornadoes, are possible across parts of Florida and southern Georgia this afternoon, and again overnight. ...20Z Update... The primary change to this outlook was to confine the category 2/Slight risk to the FL peninsula. A widespread precipitation shield has overspread much of the FL Panhandle and surrounding region, limiting buoyancy inland. Offshore across the Gulf of Mexico, deeper convection associated with an MCS has resulted in tropospheric overturning, lowering confidence in airmass destabilization ahead of an approaching surface low/mid-level trough over the coastal Southeast. Still, an instance or two of damaging gusts, large hail, or a brief tornado remains possible. Otherwise, the previous forecast remains on track, with severe potential remaining in place across the FL Peninsula with the approach of the aforementioned MCS and preceding sea-breeze convection. A second round of strong to potentially severe storms may still occur across the FL Peninsula later tonight into tomorrow morning with the approach of a surface cold front. ..Squitieri.. 04/29/2023 .PREV DISCUSSION... /ISSUED 1125 AM CDT Sat Apr 29 2023/ ...FL area through tonight... A large cluster of thunderstorms over the northeast Gulf of Mexico appears to be developing into an MCS, in advance of a pronounced midlevel shortwave trough over the northwest Gulf coast. The developing MCS is expected to progress east-northeastward over central/north FL later this afternoon/evening, along and south of a stalled front. Boundary-layer dewpoints near 70 F and surface heating in cloud breaks will result in destabilization sufficient to maintain the MCS and an attendant threat for damaging winds late this afternoon. Aside from the MCS, cyclogenesis appears likely near the Southeast Atlantic coast along the stalled front by tonight, as the Gulf of Mexico shortwave trough begins to phase with a deep low over the Great Lakes. There will be some threat for additional storm development overnight in association with the primary Gulf of Mexico shortwave trough and cold front, in the wake of the afternoon MCS. Wind profiles will strengthen with time tonight with the approach of the shortwave trough and cyclogenesis. However, the main concern overnight will be any reductions in moisture/buoyancy by today's convection. Other storms may form this afternoon along the Atlantic coast sea breeze from southeast into east central FL. MLCAPE in excess of 2500 J/kg and effective bulk shear of 35-50 kt (driven by relatively weak low-level flow and stronger flow aloft) will support the potential for organized/supercell storms with the potential to produce isolated large hail and damaging winds. ...Coastal Carolinas late this afternoon into tonight... The surface warm/moist sector will remain near the Atlantic coast this afternoon, and an isolated strong storm may form along the boundary this afternoon in southern NC. By tonight, there will be a gradual increase in vertical shear in response to cyclogenesis, as well as the possibility of a remnant MCV emerging from the Gulf of Mexico MCS. There will be a conditional threat for organized/supercell storms, though the details of thunderstorm coverage/evolution will depend on the future influence of the Gulf of Mexico convection, which is still uncertain this far northeast. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0259 PM CDT Sat Apr 29 2023 Valid 292000Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTION OF THE CENTRAL FLORIDA PENINSULA... ...SUMMARY... Two rounds of severe thunderstorms, with damaging winds, large hail, and a coup[e of tornadoes, are possible across parts of Florida and southern Georgia this afternoon, and again overnight. ...20Z Update... The primary change to this outlook was to confine the category 2/Slight risk to the FL peninsula. A widespread precipitation shield has overspread much of the FL Panhandle and surrounding region, limiting buoyancy inland. Offshore across the Gulf of Mexico, deeper convection associated with an MCS has resulted in tropospheric overturning, lowering confidence in airmass destabilization ahead of an approaching surface low/mid-level trough over the coastal Southeast. Still, an instance or two of damaging gusts, large hail, or a brief tornado remains possible. Otherwise, the previous forecast remains on track, with severe potential remaining in place across the FL Peninsula with the approach of the aforementioned MCS and preceding sea-breeze convection. A second round of strong to potentially severe storms may still occur across the FL Peninsula later tonight into tomorrow morning with the approach of a surface cold front. ..Squitieri.. 04/29/2023 .PREV DISCUSSION... /ISSUED 1125 AM CDT Sat Apr 29 2023/ ...FL area through tonight... A large cluster of thunderstorms over the northeast Gulf of Mexico appears to be developing into an MCS, in advance of a pronounced midlevel shortwave trough over the northwest Gulf coast. The developing MCS is expected to progress east-northeastward over central/north FL later this afternoon/evening, along and south of a stalled front. Boundary-layer dewpoints near 70 F and surface heating in cloud breaks will result in destabilization sufficient to maintain the MCS and an attendant threat for damaging winds late this afternoon. Aside from the MCS, cyclogenesis appears likely near the Southeast Atlantic coast along the stalled front by tonight, as the Gulf of Mexico shortwave trough begins to phase with a deep low over the Great Lakes. There will be some threat for additional storm development overnight in association with the primary Gulf of Mexico shortwave trough and cold front, in the wake of the afternoon MCS. Wind profiles will strengthen with time tonight with the approach of the shortwave trough and cyclogenesis. However, the main concern overnight will be any reductions in moisture/buoyancy by today's convection. Other storms may form this afternoon along the Atlantic coast sea breeze from southeast into east central FL. MLCAPE in excess of 2500 J/kg and effective bulk shear of 35-50 kt (driven by relatively weak low-level flow and stronger flow aloft) will support the potential for organized/supercell storms with the potential to produce isolated large hail and damaging winds. ...Coastal Carolinas late this afternoon into tonight... The surface warm/moist sector will remain near the Atlantic coast this afternoon, and an isolated strong storm may form along the boundary this afternoon in southern NC. By tonight, there will be a gradual increase in vertical shear in response to cyclogenesis, as well as the possibility of a remnant MCV emerging from the Gulf of Mexico MCS. There will be a conditional threat for organized/supercell storms, though the details of thunderstorm coverage/evolution will depend on the future influence of the Gulf of Mexico convection, which is still uncertain this far northeast. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0212 PM CDT Sat Apr 29 2023 Valid 301200Z - 011200Z Only minor adjustments were made to the D2 Elevated to align with current trends. See previous discussion below for more information. ..Thornton.. 04/29/2023 .PREV DISCUSSION... /ISSUED 0208 AM CDT Sat Apr 29 2023/ ...Synopsis... Elevated fire weather conditions are expected to persist across the Plains on Sunday, but will mainly be focused across portions of NE and KS. Short to medium-range guidance shows a somewhat stagnant upper-level pattern over the next 48 hours, with a persistent surface low lingering over the upper MS Valley/Great Lakes region. This will maintain a strong pressure gradient over the Plains with another day of sustained 15-25 mph winds (gusting to 30-40 mph) likely. An influx of cooler continental air will limit the spatial extent of sub-25% RH reductions, and recent ensemble guidance suggests the highest probability for favorable overlap of dry/breezy conditions resides over parts of NE to northern KS. While parts of this region have received recent rainfall, local fuel analyses show ERCs generally in the 60-90th percentile range, which should support the fire weather concern. Forecast adjustments are possible given the potential for drying of fine grasses on D1/Saturday. ...Eastern New Mexico to West Texas... Localized elevated fire weather conditions are possible Sunday afternoon across parts of the southern High Plains. Increasing downslope flow off the southern Rockies will foster warming/drying across eastern NM to west TX. Winds near 15 mph, coupled with 15-20% RH, should allow for areas of elevated conditions. However, the displacement of this region from the stronger mid-level flow to the north casts some uncertainty onto the spatial coverage and duration of elevated conditions. Trends will be monitored, and an additional risk area may be needed considering the fairly dry fuels across parts of the region. ...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 0212 PM CDT Sat Apr 29 2023 Valid 301200Z - 011200Z Only minor adjustments were made to the D2 Elevated to align with current trends. See previous discussion below for more information. ..Thornton.. 04/29/2023 .PREV DISCUSSION... /ISSUED 0208 AM CDT Sat Apr 29 2023/ ...Synopsis... Elevated fire weather conditions are expected to persist across the Plains on Sunday, but will mainly be focused across portions of NE and KS. Short to medium-range guidance shows a somewhat stagnant upper-level pattern over the next 48 hours, with a persistent surface low lingering over the upper MS Valley/Great Lakes region. This will maintain a strong pressure gradient over the Plains with another day of sustained 15-25 mph winds (gusting to 30-40 mph) likely. An influx of cooler continental air will limit the spatial extent of sub-25% RH reductions, and recent ensemble guidance suggests the highest probability for favorable overlap of dry/breezy conditions resides over parts of NE to northern KS. While parts of this region have received recent rainfall, local fuel analyses show ERCs generally in the 60-90th percentile range, which should support the fire weather concern. Forecast adjustments are possible given the potential for drying of fine grasses on D1/Saturday. ...Eastern New Mexico to West Texas... Localized elevated fire weather conditions are possible Sunday afternoon across parts of the southern High Plains. Increasing downslope flow off the southern Rockies will foster warming/drying across eastern NM to west TX. Winds near 15 mph, coupled with 15-20% RH, should allow for areas of elevated conditions. However, the displacement of this region from the stronger mid-level flow to the north casts some uncertainty onto the spatial coverage and duration of elevated conditions. Trends will be monitored, and an additional risk area may be needed considering the fairly dry fuels across parts of the region. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1229 PM CDT Sat Apr 29 2023 Valid 301200Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF EASTERN NORTH CAROLINA INTO FAR SOUTHEAST VIRGINIA AND THE CENTRAL AND SOUTHERN FLORIDA PENINSULA... ...SUMMARY... Severe thunderstorms will be possible across parts of the Carolinas into the Mid Atlantic, and also across parts of central and south Florida. Damaging winds and a few tornadoes will be the primary hazards, though isolated hail will also be possible. ...Synopsis... A mid-level trough will eject into the Atlantic Ocean as a surface low deepens while traversing the Atlantic Seaboard. Before the surface cold front trailing the low moves offshore, adequate low-level moisture advection and veering/strengthening tropospheric winds ahead of the front will foster a risk for strong to severe thunderstorms across portions of the Carolina Piedmont and southern Mid Atlantic and central and southern portions of the FL Peninsula. ...Carolina Piedmont into the southern Mid Atlantic... A surface low is expected to be positioned roughly over NC at the start of the period, with southerly low-level flow advecting at least mid 60s F surface dewpoints beneath modest mid-level lapse rates, contributing to over 1000 J/kg MLCAPE. A 40+ kt low-level jet will overspread the Carolinas during the morning hours as an 80+ kt 500 mb jet streak impinges on the region, contributing to long, slightly curved hodographs and well over 50 kts of effective bulk shear. Damaging gusts and a couple of tornadoes are possible with the stronger discrete/semi-discrete supercells or line segments that can materialize around the start of the period. Later in the afternoon, enough insolation and boundary-layer modification behind the first round of convection may support additional storm development ahead of the cold front. While a tornado cannot be ruled out with this second round of storms, damaging gusts may be a relatively greater concern as the northward departure of the surface low will result in straighter hodographs compared to earlier in the day. Some severe threat may continue to spread northward in tandem with the surface low into the Mid Atlantic. However, accompanying buoyancy should be scant and the severe risk is expected to be isolated, with a damaging gust or tornado possible. ...Central and southern FL Peninsula... The severe threat will be confined to roughly the 12-20Z period, before the trailing surface cold front shunts the better quality low-level moisture offshore. From morning to early-afternoon, 70+ F surface dewpoints overspread by 6.5-7 C/km tropospheric lapse rates will contribute to 1500 + J/kg MLCAPE amid elongated, modestly curved hodographs (with over 50 kts of effective bulk shear and around 200 m2/s2 of effective SRH). As such, a mix of line segments and semi-discrete supercells may pose a damaging gust/tornado threat before the cold front moves offshore. ..Squitieri.. 04/29/2023 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1229 PM CDT Sat Apr 29 2023 Valid 301200Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF EASTERN NORTH CAROLINA INTO FAR SOUTHEAST VIRGINIA AND THE CENTRAL AND SOUTHERN FLORIDA PENINSULA... ...SUMMARY... Severe thunderstorms will be possible across parts of the Carolinas into the Mid Atlantic, and also across parts of central and south Florida. Damaging winds and a few tornadoes will be the primary hazards, though isolated hail will also be possible. ...Synopsis... A mid-level trough will eject into the Atlantic Ocean as a surface low deepens while traversing the Atlantic Seaboard. Before the surface cold front trailing the low moves offshore, adequate low-level moisture advection and veering/strengthening tropospheric winds ahead of the front will foster a risk for strong to severe thunderstorms across portions of the Carolina Piedmont and southern Mid Atlantic and central and southern portions of the FL Peninsula. ...Carolina Piedmont into the southern Mid Atlantic... A surface low is expected to be positioned roughly over NC at the start of the period, with southerly low-level flow advecting at least mid 60s F surface dewpoints beneath modest mid-level lapse rates, contributing to over 1000 J/kg MLCAPE. A 40+ kt low-level jet will overspread the Carolinas during the morning hours as an 80+ kt 500 mb jet streak impinges on the region, contributing to long, slightly curved hodographs and well over 50 kts of effective bulk shear. Damaging gusts and a couple of tornadoes are possible with the stronger discrete/semi-discrete supercells or line segments that can materialize around the start of the period. Later in the afternoon, enough insolation and boundary-layer modification behind the first round of convection may support additional storm development ahead of the cold front. While a tornado cannot be ruled out with this second round of storms, damaging gusts may be a relatively greater concern as the northward departure of the surface low will result in straighter hodographs compared to earlier in the day. Some severe threat may continue to spread northward in tandem with the surface low into the Mid Atlantic. However, accompanying buoyancy should be scant and the severe risk is expected to be isolated, with a damaging gust or tornado possible. ...Central and southern FL Peninsula... The severe threat will be confined to roughly the 12-20Z period, before the trailing surface cold front shunts the better quality low-level moisture offshore. From morning to early-afternoon, 70+ F surface dewpoints overspread by 6.5-7 C/km tropospheric lapse rates will contribute to 1500 + J/kg MLCAPE amid elongated, modestly curved hodographs (with over 50 kts of effective bulk shear and around 200 m2/s2 of effective SRH). As such, a mix of line segments and semi-discrete supercells may pose a damaging gust/tornado threat before the cold front moves offshore. ..Squitieri.. 04/29/2023 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1140 AM CDT Sat Apr 29 2023 Valid 291700Z - 301200Z The current D1 Fire Weather outlook is on track with no updates needed. See previous discussion below. ..Thornton.. 04/29/2023 .PREV DISCUSSION... /ISSUED 0135 AM CDT Sat Apr 29 2023/ ...Synopsis... Elevated fire weather conditions are expected this afternoon across parts of the central Plains. Latest water-vapor imagery and upper-air analyses show a strong upper jet associated with an approaching wave nosing into the northern Plains. Surface pressure falls associated with this feature are already noted across parts of the upper MS Valley region, and a diffuse surface low over the Great Lakes is forecast to deepen over the next 24 hours. This will augment regional pressure-gradient winds across much of the Plains this afternoon. Widespread sustained winds between 15-25 mph are anticipated from the Dakotas southward into KS with gusts up to 35-45 mph probable. Diurnal warming, coupled with an unseasonably dry air mass (dewpoint values near the 10th percentile for late April across central NE), will foster afternoon RH reductions into the low 20s to teens. Consequently, a broad swath of elevated fire weather conditions is expected with periodic critical conditions possible. However, fuels remain only somewhat receptive across the region after recent rainfall. The Elevated risk is maintained over areas where fuels should be most receptive and elevated/critical wind/RH conditions are expected. ...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 1140 AM CDT Sat Apr 29 2023 Valid 291700Z - 301200Z The current D1 Fire Weather outlook is on track with no updates needed. See previous discussion below. ..Thornton.. 04/29/2023 .PREV DISCUSSION... /ISSUED 0135 AM CDT Sat Apr 29 2023/ ...Synopsis... Elevated fire weather conditions are expected this afternoon across parts of the central Plains. Latest water-vapor imagery and upper-air analyses show a strong upper jet associated with an approaching wave nosing into the northern Plains. Surface pressure falls associated with this feature are already noted across parts of the upper MS Valley region, and a diffuse surface low over the Great Lakes is forecast to deepen over the next 24 hours. This will augment regional pressure-gradient winds across much of the Plains this afternoon. Widespread sustained winds between 15-25 mph are anticipated from the Dakotas southward into KS with gusts up to 35-45 mph probable. Diurnal warming, coupled with an unseasonably dry air mass (dewpoint values near the 10th percentile for late April across central NE), will foster afternoon RH reductions into the low 20s to teens. Consequently, a broad swath of elevated fire weather conditions is expected with periodic critical conditions possible. However, fuels remain only somewhat receptive across the region after recent rainfall. The Elevated risk is maintained over areas where fuels should be most receptive and elevated/critical wind/RH conditions are expected. ...Please see www.spc.noaa.gov/fire for graphic product... Read more