Severe Storms

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1003 AM CST Fri Jan 06 2023 Valid 061700Z - 071200Z ...NO CRITICAL AREAS... The previous forecast is largely on track. Expect far eastern New Mexico into the Texas and Oklahoma panhandles to see spotty and transient elevated fire conditions, with gusts up to 20-25 kts and RH near 15-20% this afternoon. However, ERCs near seasonal averages prevent the introduction of Elevated risk areas. In south Florida, ERCs are near the 90th percentile, and RH is expected to be low (25-30%) this afternoon with diurnal mixing. However, weak winds will keep elevated fire risk localized. See the previous discussion for more details. ..Supinie/Lyons.. 01/06/2023 .PREV DISCUSSION... /ISSUED 1004 PM CST Thu Jan 05 2023/ ...Synopsis... A mid-level trough will traverse the southern Rockies and overspread portions of the south-central U.S. today, prompting surface low development across the southern Plains. To the west of the surface low, dry and breezy conditions should develop across the southern High Plains due to both gradient and downslope components of flow. 15-25 percent RH overlapping 15+ mph sustained westerly surface winds are expected by afternoon peaking heating across portions of far eastern New Mexico into western Texas and the Texas/Oklahoma Panhandle area. While such conditions typically necessitate the introduction of Elevated highlights, fuels are marginally receptive (at best) to wildfire spread, so fire weather highlights have been withheld this outlook. ...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 0103 PM CST Thu Jan 05 2023 Valid 061200Z - 071200Z ...NO CRITICAL AREAS... The previous discussion remains on track with no changes required. Latest ensemble guidance continues to show relatively weak signals for sustained elevated conditions across eastern NM/western TX away from prominent terrain features, suggesting that localized and/or transient elevated wind/RH conditions are probable. See the previous discussion below for additional details. ...Southern Florida... A northerly flow regime with 10-15 mph winds is expected Friday afternoon across southern FL. Strong diurnal warming/mixing coupled with dry down-peninsula flow may result in RH values falling into the 25-35% range. Fire weather concerns may emerge where elevated wind/RH conditions can overlap with modestly dry fuels over the region. ..Moore.. 01/05/2023 .PREV DISCUSSION... /ISSUED 1233 AM CST Thu Jan 05 2023/ ...Synopsis... A mid-level trough will eject into the southern High Plains by late afternoon Friday. A surface low is expected to develop in southeast Colorado and shift into southwestern Kansas/northwestern Oklahoma. Ahead of a Pacific cold front, dry and windy conditions are at least possible locally within parts of eastern New Mexico and West Texas. Guidance continues to show a low probability of sustained overlap of strong winds and low RH. The strongest winds (15-25 mph) are likely to occur in northeast New Mexico into the Texas/Oklahoma Panhandles. However, RH below 20% may be brief and fine fuels are somewhat less receptive with northward extent. Higher confidence in low RH exists in southeast New Mexico into the Permian Basin/South Plains, but winds may struggle to reach much more than 15 mph away from the terrain. Locally elevated conditions are probable for some parts of the region. Confidence in where several hours of these conditions will occur is too low for highlights. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

No watches are valid as of Thu Jan 5 19:05:02 UTC 2023.

No Mesoscale Discussions are in effect as of Thu Jan 5 19:05:02 UTC 2023.

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1110 AM CST Thu Jan 05 2023 Valid 061200Z - 071200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected on Friday. ...Synopsis... A somewhat progressive upper pattern is anticipated on Friday as a pair of shortwave troughs, one initially extending from the Upper OH Valley into the Mid-Atlantic and the other from the eastern Great Basin into AZ, both move eastward across the CONUS. The lead wave is forecast to move off the Northeast coast by Friday evening while the wave in its wake moves into the central and southern Plains. Some moisture return is expected ahead of the Plains shortwave, with 60s dewpoints likely in place across much of southern, central, and east TX by Saturday morning. However, warm temperatures aloft should limit thunderstorm development within this return flow. Dry and stable conditions will preclude thunderstorm development elsewhere east of the Rockies. The upper pattern over the western CONUS should begin amplifying Friday evening into Saturday morning as another strong shortwave trough approaching the West Coast. Strong ascent and a well-defined frontal band will approach the northern CA coast Saturday morning, but any deeper convective cores capable of lightning should remain offshore. ..Mosier.. 01/05/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1025 AM CST Thu Jan 05 2023 Valid 051630Z - 061200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected today. ...Synopsis... A midlevel cyclone, evident in water vapor imagery will continue eastward across the Great Lakes vicinity through the period, while related large-scale troughing persists over the eastern CONUS. An embedded midlevel speed maximum will lift northeastward from the Southeast and eventually off the Mid-Atlantic coast, allowing the tail-end of a cold front to continue southward across the central/southern FL Peninsula. Moist/unstable boundary-layer conditions will continue supporting isolated thunderstorms along/immediately ahead of the southward-moving front today. While 30-40 kt of effective shear obliquely-oriented to the front could favor a loosely organized multicell cluster or two over central FL early this afternoon, limited large-scale ascent and poor midlevel lapse rates should temper the severe risk. Farther west, water vapor imagery and regional VWP data depict a pronounced, midlevel shortwave trough accompanied by strong west-southwesterly flow aloft tracking eastward over the CA coast. As associated strong midlevel height-falls (90m per 12hr) continue overspreading CA and parts of the Great Basin, isolated to widely scattered thunderstorms should spread eastward across the region into the overnight hours. Cold midlevel temperatures atop lower 50s boundary-layer dewpoints could yield pockets of weak surface-based instability (especially over the western portions of CA this afternoon). These conditions, coupled with 25-35 kt of effective shear, could support a few embedded cells capable of small hail and locally strong gusts. However, the weak instability/poor low-level lapse rates should generally limit storm intensity -- precluding severe probabilities. ..Weinman/Mosier.. 01/05/2023 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0944 AM CST Thu Jan 05 2023 Valid 051700Z - 061200Z ...NO CRITICAL AREAS... The previous forecast remains on track with no changes needed. Despite dry boundary-layer conditions sampled in morning soundings across west TX, the potential for widespread, sustained 15+ mph winds outside of terrain-favored locations remains very limited across the southern High Plains. See the previous discussion for additional details. ..Moore.. 01/05/2023 .PREV DISCUSSION... /ISSUED 1232 AM CST Thu Jan 05 2023/ ...Synopsis... Shortwave ridging will occur over the southern High Plains today. To the west, another upper-level shortwave trough will move into the Four Corners. As the trough approaches, weak lee troughing will occur in the southern High Plains. Given the overall light winds and marginally low RH, fire weather concerns in the region will remain low. Elsewhere, no fire weather concerns are expected. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0145 PM CST Wed Jan 04 2023 Valid 042000Z - 051200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF NORTHERN FL AND SOUTHEAST GA AS WELL AS EASTERN NC AND FAR SOUTHEAST VA... ...SUMMARY... Strong to severe thunderstorms are forecast today over portions of the Southeast and Mid-Atlantic. Damaging gusts and a couple of tornadoes are possible, mainly over parts of Georgia, the Florida Panhandle and the Carolinas. ...20Z Update... ...Southeast into the Mid-Atlantic... A broken line of showers and thunderstorms extends from eastern NC southwestward into northern FL. Strongest storms within this line are currently located over northern FL. Warm and moist conditions exist ahead of this line, supporting the potential for strong to severe storms capable of hail, damaging wind gusts, and/or brief tornadoes. Farther north, temperatures have warmed into mid 70s across northeast NC, helping to support moderate buoyancy ahead of an arcing line of thunderstorms. A few strong to severe storms are possible within this line as it continue northeastward through the remainder of northeast NC and into far southeast VA. Primary hazards with these storms are damaging wind gusts and a tornado or two. ...Central California Coast... Convectively enhanced damaging wind gusts are still possible tonight across the central CA coast as a strong frontal band moves onshore. Most recent guidance indicates the band will likely impact the region from 02Z to 09Z. ..Mosier.. 01/04/2023 .PREV DISCUSSION... /ISSUED 1027 AM CST Wed Jan 04 2023/ ...Southeast into the Mid-Atlantic... A midlevel cyclone (evident in water vapor imagery) currently centered over southern MN will move slowly east-southeastward into southern WI through the period. Peripheral to this cyclone, broad/enhanced cyclonic flow aloft will persist across the eastern CONUS, while an embedded southwesterly midlevel speed max lifts northeastward from the TN Valley toward the Northeast and weakens with time. At the surface, a cold front, currently extending from the Ohio Valley south-southwestward into the central Gulf Coast, will advance eastward toward the East Coast. Ahead of the cold front, a QLCS extending from SC south-southwestward into the FL Panhandle will continue tracking eastward this afternoon. Upper 60s boundary-layer dewpoints and pockets of diurnal heating/destabilization ahead of the convective line will continue to support surface-based inflow for this activity as it continues toward the coast. And, 40-50 kt of effective shear oriented mostly parallel to the leading-edge gust front will favor a continued organized/linear mode with a primary risk of damaging gusts and perhaps a couple of embedded mesovortex tornadoes. The tornado and damaging-wind risk should be maximized with any north-south-oriented segments of the line, where deep-layer flow/shear will be more favorably oriented to the gust front. For details regarding the ongoing severe risk over this area, refer to Tornado Watch 13 and Mesoscale Discussion 34. Farther north into eastern North Carolina, additional thunderstorm development is underway along the eastern edge of widespread cloud coverage extending across western North Carolina. During the next couple of hours, continued diurnal destabilization across the warm sector will yield moderate instability amid strong deep-layer southwesterly flow, with 45-55 kt of effective shear and modest low-level hodograph curvature. As a result, storms should gradually intensify as they intercept this favorable environment this afternoon. A mixed-mode, consisting of supercell clusters and line segments, will pose a risk of locally damaging gusts and a couple of tornadoes this afternoon. For more details, refer to Tornado Watch 14. ...California Coast... While cloud coverage will generally limit diurnal heating along the CA coast today, at least pockets of heating/mixing amid lower/middle 50s dewpoints should yield weak surface-based instability by the evening/overnight hours. Strong DCVA ahead of an approaching midlevel trough and a strengthening low-level jet should aid isolated thunderstorm development during the evening/overnight hours. 40+ kt of deep-layer shear should support a loosely organized frontal band of convection capable of strong to locally damaging gusts. Read more

No Mesoscale Discussions are in effect as of Wed Jan 4 19:49:03 UTC 2023.

WW 0014 Status Updates
STATUS REPORT ON WW 14 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 50 SE CRE TO 30 NNE CRE TO 10 NNE OAJ. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 0036 ..WEINMAN..01/04/23 ATTN...WFO...ILM...RAH... STATUS REPORT FOR WT 14 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS NCC019-129-141-042040- NC . NORTH CAROLINA COUNTIES INCLUDED ARE BRUNSWICK NEW HANOVER PENDER AMZ250-252-042040- CW . ADJACENT COASTAL WATERS INCLUDED ARE COASTAL WATERS FROM SURF CITY TO CAPE FEAR NC OUT 20 NM COASTAL WATERS FROM CAPE FEAR NC TO LITTLE RIVER INLET SC OUT 20 NM THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more

WW 14 TORNADO NC SC CW 041620Z - 042200Z
URGENT - IMMEDIATE BROADCAST REQUESTED Tornado Watch Number 14 NWS Storm Prediction Center Norman OK 1020 AM CST Wed Jan 4 2023 The NWS Storm Prediction Center has issued a * Tornado Watch for portions of Southeast North Carolina Northeast South Carolina Coastal Waters * Effective this Wednesday morning and afternoon from 1020 AM until 400 PM CST. * Primary threats include... A couple tornadoes possible Scattered damaging wind gusts to 70 mph possible SUMMARY...A line of thunderstorms capable of locally damaging wind gusts and a few brief tornadoes will track eastward across the watch area this afternoon. The tornado watch area is approximately along and 65 statute miles north and south of a line from 35 miles west southwest of Florence SC to 15 miles south southeast of Wilmington NC. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU4). 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. && OTHER WATCH INFORMATION...CONTINUE...WW 12...WW 13... AVIATION...Tornadoes and a few severe thunderstorms with hail surface and aloft to 0.5 inches. Extreme turbulence and surface wind gusts to 60 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 25035. ...Hart Read more

WW 0013 Status Updates
STATUS REPORT ON WW 13 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 40 W CTY TO 30 SSE VDI TO 15 ESE SAV. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 0035 ..WEINMAN..01/04/23 ATTN...WFO...JAX...TAE...CHS...CAE...FFC... STATUS REPORT FOR WT 13 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS FLC003-023-047-067-089-121-041940- FL . FLORIDA COUNTIES INCLUDED ARE BAKER COLUMBIA HAMILTON LAFAYETTE NASSAU SUWANNEE GAC001-005-025-039-049-051-065-101-127-179-183-191-229-299-305- 041940- GA . GEORGIA COUNTIES INCLUDED ARE APPLING BACON BRANTLEY CAMDEN CHARLTON CHATHAM CLINCH ECHOLS GLYNN LIBERTY LONG MCINTOSH PIERCE WARE WAYNE SCC015-019-041940- Read more

WW 13 TORNADO FL GA SC CW 041335Z - 041900Z
URGENT - IMMEDIATE BROADCAST REQUESTED Tornado Watch Number 13 NWS Storm Prediction Center Norman OK 835 AM EST Wed Jan 4 2023 The NWS Storm Prediction Center has issued a * Tornado Watch for portions of Northern Florida and eastern Florida Panhandle Eastern and southern Georgia Southern and central South Carolina Coastal Waters * Effective this Wednesday morning and afternoon from 835 AM until 200 PM EST. * Primary threats include... A couple tornadoes possible Scattered damaging wind gusts to 70 mph possible SUMMARY...A line of strong-severe thunderstorms should proceed eastward out of tornado watch 12 and across this area, offering damaging winds and the potential for a couple tornadoes before it weakens later today. The tornado watch area is approximately along and 60 statute miles east and west of a line from 40 miles southeast of Tallahassee FL to 35 miles north northeast of Columbia SC. 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. && OTHER WATCH INFORMATION...CONTINUE...WW 12... AVIATION...Tornadoes and a few severe thunderstorms with hail surface and aloft to 1 inch. Extreme turbulence and surface wind gusts to 60 knots. A few cumulonimbi with maximum tops to 450. Mean storm motion vector 24035. ...Edwards Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1221 PM CST Wed Jan 04 2023 Valid 051200Z - 061200Z ...NO CRITICAL AREAS... The previous forecast remains on track with no changes required. Latest guidance maintains weak winds (10-15 mph) across the southern High Plains amid RH in the low to mid 20s with minimal signal for sustained elevated fire weather conditions. See the previous discussion for further details. ..Moore.. 01/04/2023 .PREV DISCUSSION... /ISSUED 1246 AM CST Wed Jan 04 2023/ ...Synopsis... Shortwave ridging will shift eastward out of the Southwest and into the southern Plains through the day on Thursday. Two upper-level troughs will bookend this feature. At the surface, a weak lee trough will develop in the southern High Plains. Despite the lee trough, weak surface winds across the region and RH above critical thresholds will keep fire weather concerns low. Elsewhere in the U.S. fire weather concerns are not expected. ...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 1221 PM CST Wed Jan 04 2023 Valid 051200Z - 061200Z ...NO CRITICAL AREAS... The previous forecast remains on track with no changes required. Latest guidance maintains weak winds (10-15 mph) across the southern High Plains amid RH in the low to mid 20s with minimal signal for sustained elevated fire weather conditions. See the previous discussion for further details. ..Moore.. 01/04/2023 .PREV DISCUSSION... /ISSUED 1246 AM CST Wed Jan 04 2023/ ...Synopsis... Shortwave ridging will shift eastward out of the Southwest and into the southern Plains through the day on Thursday. Two upper-level troughs will bookend this feature. At the surface, a weak lee trough will develop in the southern High Plains. Despite the lee trough, weak surface winds across the region and RH above critical thresholds will keep fire weather concerns low. Elsewhere in the U.S. fire weather concerns are not expected. ...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 1108 AM CST Wed Jan 04 2023 Valid 051200Z - 061200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected on Thursday. ...Synopsis... A mature mid-latitude cyclone is forecast to be centered near the IA/IL/WI border intersection early Thursday morning. This cyclone is expected to trend more progressive throughout the day, moving eastward across the Great Lakes and into the Northeast. During the same period, a strong shortwave trough (accompanied by a robust mid-level jet streak) will move through the base of the this cyclone. This overall evolution will lead to a deamplification of the upper pattern east of the Rockies, as well as reinforcement of the dry and stable conditions already in place across much of the central/eastern CONUS. This will preclude thunderstorm development in these areas, with the exception of the central FL Peninsula, where a weak, southward-progressing may help initiate a few thunderstorms during the afternoon. Farther west, a deep upper trough will likely extend along the length of the West Coast early Thursday morning. Bifurcation of this upper trough is anticipated throughout the period, as a shortwave trough embedded within the large upper troughing progresses through central and southern CA. By the early Friday morning, this shortwave is expected to extend across the Great Basin into the Lower CO River Valley. Strong forcing for ascent and cold mid-level temperatures will contribute to the potential for isolated lightning strikes across much of central and southern CA. The highest thunderstorm coverage across central CA is expected from Thursday morning into the late afternoon, while the highest coverage across southern CA is expected Thursday afternoon through the evening. ..Mosier.. 01/04/2023 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1108 AM CST Wed Jan 04 2023 Valid 051200Z - 061200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected on Thursday. ...Synopsis... A mature mid-latitude cyclone is forecast to be centered near the IA/IL/WI border intersection early Thursday morning. This cyclone is expected to trend more progressive throughout the day, moving eastward across the Great Lakes and into the Northeast. During the same period, a strong shortwave trough (accompanied by a robust mid-level jet streak) will move through the base of the this cyclone. This overall evolution will lead to a deamplification of the upper pattern east of the Rockies, as well as reinforcement of the dry and stable conditions already in place across much of the central/eastern CONUS. This will preclude thunderstorm development in these areas, with the exception of the central FL Peninsula, where a weak, southward-progressing may help initiate a few thunderstorms during the afternoon. Farther west, a deep upper trough will likely extend along the length of the West Coast early Thursday morning. Bifurcation of this upper trough is anticipated throughout the period, as a shortwave trough embedded within the large upper troughing progresses through central and southern CA. By the early Friday morning, this shortwave is expected to extend across the Great Basin into the Lower CO River Valley. Strong forcing for ascent and cold mid-level temperatures will contribute to the potential for isolated lightning strikes across much of central and southern CA. The highest thunderstorm coverage across central CA is expected from Thursday morning into the late afternoon, while the highest coverage across southern CA is expected Thursday afternoon through the evening. ..Mosier.. 01/04/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1027 AM CST Wed Jan 04 2023 Valid 041630Z - 051200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF NORTHERN FLORIDA...SOUTHEAST GEORGIA...AND THE EASTERN CAROLINAS... ...SUMMARY... Strong to severe thunderstorms are forecast today over portions of the Southeast and Mid-Atlantic. Damaging gusts and a couple of tornadoes are possible, mainly over parts of Georgia, the Florida Panhandle and the Carolinas. ...Southeast into the Mid-Atlantic... A midlevel cyclone (evident in water vapor imagery) currently centered over southern MN will move slowly east-southeastward into southern WI through the period. Peripheral to this cyclone, broad/enhanced cyclonic flow aloft will persist across the eastern CONUS, while an embedded southwesterly midlevel speed max lifts northeastward from the TN Valley toward the Northeast and weakens with time. At the surface, a cold front, currently extending from the Ohio Valley south-southwestward into the central Gulf Coast, will advance eastward toward the East Coast. Ahead of the cold front, a QLCS extending from SC south-southwestward into the FL Panhandle will continue tracking eastward this afternoon. Upper 60s boundary-layer dewpoints and pockets of diurnal heating/destabilization ahead of the convective line will continue to support surface-based inflow for this activity as it continues toward the coast. And, 40-50 kt of effective shear oriented mostly parallel to the leading-edge gust front will favor a continued organized/linear mode with a primary risk of damaging gusts and perhaps a couple of embedded mesovortex tornadoes. The tornado and damaging-wind risk should be maximized with any north-south-oriented segments of the line, where deep-layer flow/shear will be more favorably oriented to the gust front. For details regarding the ongoing severe risk over this area, refer to Tornado Watch 13 and Mesoscale Discussion 34. Farther north into eastern North Carolina, additional thunderstorm development is underway along the eastern edge of widespread cloud coverage extending across western North Carolina. During the next couple of hours, continued diurnal destabilization across the warm sector will yield moderate instability amid strong deep-layer southwesterly flow, with 45-55 kt of effective shear and modest low-level hodograph curvature. As a result, storms should gradually intensify as they intercept this favorable environment this afternoon. A mixed-mode, consisting of supercell clusters and line segments, will pose a risk of locally damaging gusts and a couple of tornadoes this afternoon. For more details, refer to Tornado Watch 14. ...California Coast... While cloud coverage will generally limit diurnal heating along the CA coast today, at least pockets of heating/mixing amid lower/middle 50s dewpoints should yield weak surface-based instability by the evening/overnight hours. Strong DCVA ahead of an approaching midlevel trough and a strengthening low-level jet should aid isolated thunderstorm development during the evening/overnight hours. 40+ kt of deep-layer shear should support a loosely organized frontal band of convection capable of strong to locally damaging gusts. ..Weinman/Goss.. 01/04/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1027 AM CST Wed Jan 04 2023 Valid 041630Z - 051200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF NORTHERN FLORIDA...SOUTHEAST GEORGIA...AND THE EASTERN CAROLINAS... ...SUMMARY... Strong to severe thunderstorms are forecast today over portions of the Southeast and Mid-Atlantic. Damaging gusts and a couple of tornadoes are possible, mainly over parts of Georgia, the Florida Panhandle and the Carolinas. ...Southeast into the Mid-Atlantic... A midlevel cyclone (evident in water vapor imagery) currently centered over southern MN will move slowly east-southeastward into southern WI through the period. Peripheral to this cyclone, broad/enhanced cyclonic flow aloft will persist across the eastern CONUS, while an embedded southwesterly midlevel speed max lifts northeastward from the TN Valley toward the Northeast and weakens with time. At the surface, a cold front, currently extending from the Ohio Valley south-southwestward into the central Gulf Coast, will advance eastward toward the East Coast. Ahead of the cold front, a QLCS extending from SC south-southwestward into the FL Panhandle will continue tracking eastward this afternoon. Upper 60s boundary-layer dewpoints and pockets of diurnal heating/destabilization ahead of the convective line will continue to support surface-based inflow for this activity as it continues toward the coast. And, 40-50 kt of effective shear oriented mostly parallel to the leading-edge gust front will favor a continued organized/linear mode with a primary risk of damaging gusts and perhaps a couple of embedded mesovortex tornadoes. The tornado and damaging-wind risk should be maximized with any north-south-oriented segments of the line, where deep-layer flow/shear will be more favorably oriented to the gust front. For details regarding the ongoing severe risk over this area, refer to Tornado Watch 13 and Mesoscale Discussion 34. Farther north into eastern North Carolina, additional thunderstorm development is underway along the eastern edge of widespread cloud coverage extending across western North Carolina. During the next couple of hours, continued diurnal destabilization across the warm sector will yield moderate instability amid strong deep-layer southwesterly flow, with 45-55 kt of effective shear and modest low-level hodograph curvature. As a result, storms should gradually intensify as they intercept this favorable environment this afternoon. A mixed-mode, consisting of supercell clusters and line segments, will pose a risk of locally damaging gusts and a couple of tornadoes this afternoon. For more details, refer to Tornado Watch 14. ...California Coast... While cloud coverage will generally limit diurnal heating along the CA coast today, at least pockets of heating/mixing amid lower/middle 50s dewpoints should yield weak surface-based instability by the evening/overnight hours. Strong DCVA ahead of an approaching midlevel trough and a strengthening low-level jet should aid isolated thunderstorm development during the evening/overnight hours. 40+ kt of deep-layer shear should support a loosely organized frontal band of convection capable of strong to locally damaging gusts. ..Weinman/Goss.. 01/04/2023 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0912 AM CST Wed Jan 04 2023 Valid 041700Z - 051200Z ...NO CRITICAL AREAS... Morning observations indicate that the previous forecast is on track. Only transient elevated conditions are expected across the Permian basin, where fuels are at seasonal dryness levels. Farther east across south-central Texas, where 10-hour fuels are drier, guidance indicates conditions will remain well below elevated fire risk thresholds. See the previous discussion for more details. ..Supinie/Moore.. 01/04/2023 .PREV DISCUSSION... /ISSUED 1243 AM CST Wed Jan 04 2023/ ...Synopsis... An upper-level low will slowly progress eastward in the Midwest while a ridge builds into the Four Corners. Strong northwesterly mid-level winds will develop from the central Rockies into the southern Plains today as a result. At the surface, the pressure gradient within the southern Plains will remain rather weak. Some areas of 15-20 mph winds may develop for a couple of hours. The most likely place for this will be from east-central New Mexico into the Permian Basin underneath a belt of stronger 850 mb winds. RH may reach 20% at least briefly as well. Given continued model spread, low ensemble probabilities for sustain elevated conditions, and only modestly dry fuels, only locally elevated conditions are expected. ...Please see www.spc.noaa.gov/fire for graphic product... Read more