Severe Storms

No Mesoscale Discussions are in effect as of Sat Feb 4 20:34:01 UTC 2023.

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0111 PM CST Sat Feb 04 2023 Valid 042000Z - 051200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected through tonight. No changes were made to the previous outlook, as thunderstorm chances in general remain low. A few convective showers may linger over far southern Florida, with a better chance of lightning tonight over northern California as an upper trough moves ashore. Weak instability profiles will preclude any severe threat. ..Jewell.. 02/04/2023 .PREV DISCUSSION... /ISSUED 1022 AM CST Sat Feb 04 2023/ ...Northern CA... A shortwave impulse embedded within a broader northeast Pacific upper trough will impinge on the northern half of the CA coast tonight. The warm conveyor region ahead of this wave will yield an eastward-moving precipitation band crossing the coast this evening and into the Sierras tonight. Scant elevated buoyancy may develop within the upslope flow regime along the western Sierras and support very isolated thunderstorms. Otherwise, cooling mid-level temperatures and steepening lapse rates will foster scant surface-based instability along the northern CA coast in the early morning. Isolated thunderstorms will be possible; embedded within scattered, post-frontal low-topped convection. ...Southeast FL... Very poor mid-level lapse rates of 4-5 C/km sampled in 12Z observed soundings will curtail thunderstorm potential today. Low-level flow will shift from east-northeasterlies to southeasterlies tonight and result in gradual moistening. This should support scattered low-topped showers overnight with perhaps a thunderstorm or two in the early morning. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1152 AM CST Sat Feb 04 2023 Valid 051200Z - 061200Z The previous forecast remains largely on track. Main change was to expand the Elevated area to reflect the latest guidance consensus. Overall, fuels still appear mediocre in terms of supporting significant wildfire spread potential. But relatively dry and breezy conditions during the afternoon atop parched, dry grasses suggests that at least some potential exists for wildfire spread. ..Squitieri.. 02/04/2023 .PREV DISCUSSION... /ISSUED 0200 AM CST Sat Feb 04 2023/ ...Synopsis... An amplified large-scale trough accompanied by strong deep-layer west-southwesterly flow will overspread the western CONUS -- impinging on the central/southern Rockies by the evening hours. In response, surface lee troughing will deepen over the central/southern High Plains, promoting a corridor of 15-20 mph sustained southwesterly surface winds (with higher gusts) over northeastern NM into the western TX Panhandle. These breezy/gusty surface winds, coupled with 15-20 percent RH, will yield elevated to spotty critical conditions during the afternoon. Given continued drying of fine fuels and a lack of precipitation through this corridor, Elevated highlights have been added. While elevated to locally critical meteorological conditions are also possible farther north along the I-25 corridor in southern CO and south into southeastern NM, fuels do not appear as receptive to wildfire spread in these areas given recent precipitation/snowpack. ...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 1052 AM CST Sat Feb 04 2023 Valid 051200Z - 061200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms appear unlikely on Sunday. ...Synopsis... An upper trough will move across the western states on Sunday, taking on a positive tilt overnight across the Four Corners states. Strong cooling aloft will occur north of the midlevel jet max during the day over northern CA and NV, and heating may lead to weak instability. Scattered convective showers and a few thunderstorms are anticipated over coastal northern CA, and from the central valleys into the Sierra where westerly upslope may aid lift. Severe weather is unlikely due to weak low-level wind fields, however, cold air aloft may support graupel. Elsewhere, rain showers and a few thunderstorms may occur over parts of the FL Peninsula, where weak lift may develop in association with an upper trough extending south into the northern Gulf of Mexico. Mid 60s F dewpoints and heating will lead to weak instability, but midlevel lapse rates will remain poor, limiting storm strength. The veering low-level jet will likely focus most of the convection over the Atlantic Ocean as well. ..Jewell.. 02/04/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1022 AM CST Sat Feb 04 2023 Valid 041630Z - 051200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected through tonight. ...Northern CA... A shortwave impulse embedded within a broader northeast Pacific upper trough will impinge on the northern half of the CA coast tonight. The warm conveyor region ahead of this wave will yield an eastward-moving precipitation band crossing the coast this evening and into the Sierras tonight. Scant elevated buoyancy may develop within the upslope flow regime along the western Sierras and support very isolated thunderstorms. Otherwise, cooling mid-level temperatures and steepening lapse rates will foster scant surface-based instability along the northern CA coast in the early morning. Isolated thunderstorms will be possible; embedded within scattered, post-frontal low-topped convection. ...Southeast FL... Very poor mid-level lapse rates of 4-5 C/km sampled in 12Z observed soundings will curtail thunderstorm potential today. Low-level flow will shift from east-northeasterlies to southeasterlies tonight and result in gradual moistening. This should support scattered low-topped showers overnight with perhaps a thunderstorm or two in the early morning. ..Grams/Lyons.. 02/04/2023 Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0142 PM CST Fri Feb 03 2023 Valid 032000Z - 041200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected today or tonight. ...20Z Update... The general thunderstorm area has been trimmed with this outlook update, to account for the southward progression of convection along the outflow-reinforced cold front moving across the FL Peninsula. Thunderstorms earlier produced 40-50 mph gusts in the Melbourne vicinity, though the stronger storms have subsequently weakened or moved offshore. Any remaining thunderstorm activity across the southern FL Peninsula is expected to be generally weak and isolated, as low-level flow continues to veer and weaken ahead of the southward-moving front. ..Dean.. 02/03/2023 .PREV DISCUSSION... /ISSUED 0943 AM CST Fri Feb 03 2023/ ...Central/south FL... Scattered showers and isolated thunderstorms are ongoing along and just ahead of a cold front pushing south into central FL. 12Z observed and forecast mid-level lapse rates are weak. With only modest boundary-layer heating, limited instability will mitigate robust updrafts. Veered low-level winds ahead of the front will curtail hodograph curvature. However, the southern periphery of stronger mid-level westerlies attendant to the low-amplitude, positive-tilt shortwave trough over the Southeast will maintain 40-50 kt effective shear. Locally gusty winds and small hail are possible in the deepest storms through sunset, before onset of nocturnal cooling and weakening low-level convergence yield diminishing convection this evening in south FL. Read more

No watches are valid as of Fri Feb 3 19:46:02 UTC 2023.

No Mesoscale Discussions are in effect as of Fri Feb 3 19:46:02 UTC 2023.

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook RESENT 1 NWS Storm Prediction Center Norman OK 0109 PM CST Fri Feb 03 2023 Valid 031700Z - 041200Z ...NO CRITICAL AREAS... The previous forecast is on track. Locally elevated fire weather conditions are expected this afternoon across northeastern New Mexico and the western Texas and Oklahoma panhandles. However, only marginally dry fuels preclude adding an Elevated risk area. See the previous discussion for more details. ..Supinie.. 02/03/2023 .PREV DISCUSSION... /ISSUED 1245 AM CST Fri Feb 03 2023/ ...Synopsis... Midlevel ridging will weaken over the southern Rockies, as a low-amplitude shortwave trough overspreads the area. In response, a weak lee surface low will develop over southeastern CO, promoting 15-20 mph sustained southwesterly surface winds from northeastern NM into the TX/OK Panhandles. These winds, coupled with 20 percent minimum RH could support locally elevated conditions during the afternoon. However, given marginally receptive fuels through this corridor, Elevated highlights have been withheld. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook RESENT 1 NWS Storm Prediction Center Norman OK 0104 PM CST Fri Feb 03 2023 Valid 041200Z - 051200Z ...NO CRITICAL AREAS... The previous forecast is largely on track. A low-amplitude shortwave trough is expected to push a weak cold front through northeastern New Mexico and the Texas and Oklahoma Panhandles Saturday afternoon. The strongest winds are expected ahead of the front, while the lowest RH is expected behind the front, and this displacement precludes outlining any Elevated areas on this outlook. See the previous discussion for more details. ..Supinie.. 02/03/2023 .PREV DISCUSSION... /ISSUED 1245 AM CST Fri Feb 03 2023/ ...Synopsis... A low-amplitude shortwave trough will track eastward from the central/southern Plains into the middle MS Valley. In its wake, broad/enhanced west-northwesterly midlevel flow will persist across the central/southern Rockies -- favoring continued lee troughing and breezy surface winds over the southern Plains. While locally elevated conditions are possible over northeastern NM into the TX/OK Panhandles, the stronger surface winds should be displaced east of the more substantial RH reductions -- precluding Elevated highlights at this time. ...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 1100 AM CST Fri Feb 03 2023 Valid 041200Z - 051200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The severe-thunderstorm threat is expected to be low on Saturday. ...Synopsis... Dry and stable conditions will limit thunderstorm potential over most of the CONUS on Saturday. Isolated thunderstorms will be possible over parts of the FL Keys and southern FL Peninsula, as low-level moisture begins to recover Saturday afternoon into Saturday night in the wake of a D1/Friday cold frontal passage. Weak midlevel lapse rates should limit any severe potential with this convection. Elsewhere, low-topped convection with sporadic lightning flashes will be possible Saturday night across coastal areas of northern CA, as a mid/upper-level trough moves onshore from the eastern Pacific. ..Dean.. 02/03/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0943 AM CST Fri Feb 03 2023 Valid 031630Z - 041200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected today. ...Central/south FL... Scattered showers and isolated thunderstorms are ongoing along and just ahead of a cold front pushing south into central FL. 12Z observed and forecast mid-level lapse rates are weak. With only modest boundary-layer heating, limited instability will mitigate robust updrafts. Veered low-level winds ahead of the front will curtail hodograph curvature. However, the southern periphery of stronger mid-level westerlies attendant to the low-amplitude, positive-tilt shortwave trough over the Southeast will maintain 40-50 kt effective shear. Locally gusty winds and small hail are possible in the deepest storms through sunset, before onset of nocturnal cooling and weakening low-level convergence yield diminishing convection this evening in south FL. ..Grams/Jewell.. 02/03/2023 Read more

No watches are valid as of Thu Feb 2 20:15:02 UTC 2023.

No Mesoscale Discussions are in effect as of Thu Feb 2 20:15:02 UTC 2023.

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0157 PM CST Thu Feb 02 2023 Valid 022000Z - 031200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS MAINLY LATE TONIGHT ACROSS PARTS OF THE FLORIDA PANHANDLE... ...SUMMARY... A couple of strong thunderstorms may impact parts of the Florida Panhandle late tonight, perhaps accompanied by gusty winds. ...20Z Update... The primary change with this update is to trim the general thunderstorm line from areas where buoyancy appears too minimal for more than very isolated/sporadic lightning production. No changes have been made to the Marginal Risk area over the Florida Peninsula, where a couple of strong storms are possible tonight, with locally gusty winds possible. See the previous discussion below for more information. ..Dean.. 02/02/2023 .PREV DISCUSSION... /ISSUED 1056 AM CST Thu Feb 02 2023/ ...Synopsis... Split flow across the eastern Pacific has become less amplified, with one generally zonal belt emanating from the southern mid-latitudes likely to become increasingly influential across the U.S. today into this weekend. This will coincide with the eastward acceleration of the prominent downstream Arctic low, which has been centered near/northeast of Hudson Bay for the past week or so, and the suppression of the subtropical ridging which has been centered over the Caribbean vicinity. In response to a couple of vigorous short wave impulses digging around its western and southern periphery, the Arctic low is forecast to redevelop southward and southeastward, across Hudson Bay into Quebec, today through tonight, within larger-scale mid-level troughing amplifying southward across much of the Northeast. It appears that this will be accompanied by the initiation of strong surface cyclogenesis across southern Quebec through the lower St. Lawrence Valley, and a significant trailing intrusion of cold air across most areas east of the Rockies. An initially stalled or slower moving lead front across the Southeast into the northwestern Gulf of Mexico may slowly accelerate southeastward across much of the remainder of the eastern Gulf and south Atlantic Coast states (including northern Florida) later today through tonight, before increasingly being overtaken by the trailing front. This will occur as an upstream short wave trough continues to progress eastward, in phase with a branch of westerlies emanating from the subtropical eastern Pacific. However, this perturbation will become increasingly sheared within an increasingly confluent regime across and east of the lower Mississippi Valley, and any associated wave development along the surface front is still forecast to remain quite weak. ...Florida Panhandle vicinity... Along/ahead of the lead surface front, mid/upper 60s F surface dew points spreading inland across coastal areas between Apalachicola and Pensacola will contribute to boundary-layer destabilization today. However, CAPE is likely to remain weak, with convective development suppressed due to warm layers with weak lapse rates aloft, associated with the subtropical ridging. It is possible that forcing for ascent may increase in close proximity to the surface front as it begins to advance eastward through the Florida Panhandle late this evening and overnight. Coupled with cooling aloft, this may support increasing thunderstorm development in the presence of strong deep-layer shear. However, by this time, low-level hodographs are forecast to become more linear, with wind fields in the lowest few kilometers above ground level remaining somewhat modest (on the order of 30-40 kt around 850 mb). While a couple of storms with gusty winds approaching severe limits might not be out of the question, the risk for severe weather appears generally low. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0123 PM CST Thu Feb 02 2023 Valid 031200Z - 041200Z ...NO CRITICAL AREAS... The previous forecast is largely on track. A consensus of GFS, RAP, and ECMWF guidance suggests RH may be in the 20-30% range across northeastern New Mexico and the western Texas and Oklahoma Panhandles with gusts of 20-25 mph. When combined with marginally dry fine fuels, any elevated fire risk in this region will be localized and transient. See the previous forecast for further details. ..Supinie.. 02/02/2023 .PREV DISCUSSION... /ISSUED 0101 AM CST Thu Feb 02 2023/ ...Synopsis... Shortwave ridging is forecast to weaken quickly and shift eastward as mostly zonal westerly flow returns across the southern Plains. A shortwave trough embedded within the modest westerly flow is expected to cross the southern Rockies D2/Friday afternoon. In response to weak height falls and a slight increase in mid-level flow, a surface lee low should form across portions of southeastern CO and western KS. Aided by locally stronger downslope flow, southwest surface winds over portions of eastern NM and the western Panhandles may gust to 20 mph through the afternoon. Diurnal mixing may also support afternoon RH values below 30%. Despite the somewhat favorable meteorological conditions, recent precipitation and cold weather have limited available fuels. Some drying will likely occur as the remnant arctic airmass is quickly modified by the increase in downslope flow. However, the limited available fuels and localized nature of any fire-weather conditions suggests concerns will be low through the forecast period. ...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 1123 AM CST Thu Feb 02 2023 Valid 031200Z - 041200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The severe-thunderstorm threat appears low on Friday. ...Florida Peninsula... A deep upper-level trough will move eastward across the eastern CONUS on Friday, as a cold front sweeps through the Florida Peninsula. Along/south of the front, relatively rich low-level moisture will support modest buoyancy (MLCAPE around 500 J/kg), with rather strong midlevel flow supporting sufficient deep-layer shear for some storm organization. However, very weak midlevel lapse rates will tend to limit updraft intensity, while weakening and veering low-level flow will limit frontal convergence and storm coverage. Given these negative factors, thunderstorm coverage along/ahead of the front is expected to be isolated at best, with limited severe potential, though locally gusty winds may accompany the strongest convection across the FL Peninsula during the morning/afternoon. ..Dean.. 02/02/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook CORR 1 NWS Storm Prediction Center Norman OK 1056 AM CST Thu Feb 02 2023 Valid 021630Z - 031200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS MAINLY LATE TONIGHT ACROSS PARTS OF THE FLORIDA PANHANDLE... CORRECTED NDFD GRAPHICS ...SUMMARY... A couple of strong thunderstorms may impact parts of the Florida Panhandle late tonight, perhaps accompanied by gusty winds. ...Synopsis... Split flow across the eastern Pacific has become less amplified, with one generally zonal belt emanating from the southern mid-latitudes likely to become increasingly influential across the U.S. today into this weekend. This will coincide with the eastward acceleration of the prominent downstream Arctic low, which has been centered near/northeast of Hudson Bay for the past week or so, and the suppression of the subtropical ridging which has been centered over the Caribbean vicinity. In response to a couple of vigorous short wave impulses digging around its western and southern periphery, the Arctic low is forecast to redevelop southward and southeastward, across Hudson Bay into Quebec, today through tonight, within larger-scale mid-level troughing amplifying southward across much of the Northeast. It appears that this will be accompanied by the initiation of strong surface cyclogenesis across southern Quebec through the lower St. Lawrence Valley, and a significant trailing intrusion of cold air across most areas east of the Rockies. An initially stalled or slower moving lead front across the Southeast into the northwestern Gulf of Mexico may slowly accelerate southeastward across much of the remainder of the eastern Gulf and south Atlantic Coast states (including northern Florida) later today through tonight, before increasingly being overtaken by the trailing front. This will occur as an upstream short wave trough continues to progress eastward, in phase with a branch of westerlies emanating from the subtropical eastern Pacific. However, this perturbation will become increasingly sheared within an increasingly confluent regime across and east of the lower Mississippi Valley, and any associated wave development along the surface front is still forecast to remain quite weak. ...Florida Panhandle vicinity... Along/ahead of the lead surface front, mid/upper 60s F surface dew points spreading inland across coastal areas between Apalachicola and Pensacola will contribute to boundary-layer destabilization today. However, CAPE is likely to remain weak, with convective development suppressed due to warm layers with weak lapse rates aloft, associated with the subtropical ridging. It is possible that forcing for ascent may increase in close proximity to the surface front as it begins to advance eastward through the Florida Panhandle late this evening and overnight. Coupled with cooling aloft, this may support increasing thunderstorm development in the presence of strong deep-layer shear. However, by this time, low-level hodographs are forecast to become more linear, with wind fields in the lowest few kilometers above ground level remaining somewhat modest (on the order of 30-40 kt around 850 mb). While a couple of storms with gusty winds approaching severe limits might not be out of the question, the risk for severe weather appears generally low. ..Kerr.. 02/02/2023 Read more

No watches are valid as of Wed Feb 1 20:19:02 UTC 2023.

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0148 PM CST Wed Feb 01 2023 Valid 012000Z - 021200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast through tonight across the contiguous United States. No changes have been made to the outlook; see the previous discussion below for more information. ..Dean.. 02/01/2023 .PREV DISCUSSION... /ISSUED 1017 AM CST Wed Feb 01 2023/ ...Discussion... An upper low remains centered over the Baja Peninsula, contributing to broad southwesterly flow aloft which will persist across the southern Plains today. This southwesterly flow aloft supports a large area of stratiform precipitation extending from far west TX eastward/northeastward through the Arklatex towards the Mid-South. The upper low is forecast more progressive today through tomorrow morning, moving across northern Mexico and into the southern High Plains. As it does warm-air advection/isentropic ascent will increase ahead of it over the southern Plains, with an attendant increase in elevated buoyancy. This buoyancy supports the potential for deeper convective elements capable of lightning production, mainly after 06Z. Read more