Severe Storms

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1218 PM CDT Mon Oct 03 2022 Valid 041200Z - 051200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not forecast across the contiguous United States on Tuesday. ...Synopsis... A mid-level low over the Mid-Atlantic states will slowly move east into the adjacent Atlantic during the period as a mid-level low shifts slowly east across the Dakotas. An extension of the mid-level trough over the north-central U.S. will protrude farther southwest into NM. A plume of modest moisture and heating will promote isolated to scattered showers/thunderstorms from the Desert Southwest north-northeastward into parts of the Upper Midwest. A few lightning flashes cannot be ruled out near the immediate coast from NJ to Cape Cod. ..Smith.. 10/03/2022 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1133 AM CDT Mon Oct 03 2022 Valid 031700Z - 041200Z ...Central and Southern Plains... The previous forecast generally remains on track with only minor adjustments. Higher than expected humidity recoveries have developed farther north across portions of northeastern NE and eastern SD. Low-level drying may be somewhat delayed resulting in RH values above 25% this afternoon. Locally gusty winds may still support a few hours near-elevated fire weather concerns within very dry fuels, but widespread elevated conditions are no longer expected. Dry and breezy conditions conducive to sustained fire weather concerns are most likely across portions of western KS near the lee trough this afternoon. ..Lyons.. 10/03/2022 .PREV DISCUSSION... /ISSUED 0153 AM CDT Mon Oct 03 2022/ ...Synopsis... A mid-level trough will impinge on the northern Plains today, encouraging the persistence of surface lee troughing and associated dry southerly flow. Across the central Plains, a narrow corridor exists where Elevated dry and windy conditions will overspread receptive fuels in the absence of rainfall. Elevated highlights have been maintained in this corridor, mainly for early afternoon into early evening. ...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 1120 AM CDT Mon Oct 03 2022 Valid 031630Z - 041200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS NORTHERN ARIZONA... ...SUMMARY... A few strong to locally severe thunderstorms may occur over northern Arizona through early evening. ...Northern Arizona... A positive-tilt upper trough centered over southern Nevada will continue east-southeastward toward the Four Corners area through tonight. Steep mid-level lapse rates accompany the trough-related mid-level cold core (-14C at 500 mb). As further boundary layer heating/destabilization occurs into this afternoon, some stronger storms may develop and persist even with relatively weak winds aloft. A few of these storms could episodically produce hail to near severe levels through the afternoon before weakening by around sunset. ...North-central High Plains... Isolated stronger storms may also form later today over the Black Hills and the Nebraska Panhandle. Stronger winds aloft will promote some risk of more persistent structures, but limited low-level moisture will keep CAPE values rather low today. Nevertheless, small hail or gusty winds cannot be ruled out in a storm or two. ..Guyer/Wendt.. 10/03/2022 Read more

No watches are valid as of Sun Oct 2 18:10:02 UTC 2022.

MD 1855 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR FAR NORTHERN AZ INTO SOUTHERN/EASTERN UT AND WESTERN CO
Mesoscale Discussion 1855 NWS Storm Prediction Center Norman OK 0108 PM CDT Sun Oct 02 2022 Areas affected...far northern AZ into southern/eastern UT and western CO Concerning...Severe potential...Watch unlikely Valid 021808Z - 022115Z Probability of Watch Issuance...20 percent SUMMARY...Sporadic strong thunderstorms may produce hail and strong gusts through the afternoon from far northern AZ into southern/eastern UT and western CO. DISCUSSION...Convection is beginning to develop near the higher terrain of southern/central UT and northern AZ at midday as lower elevation temperatures warm into the 60s and 70s. Thunderstorms should slowly increase in coverage and intensity over the next few hours. Effective shear magnitudes around 25-35 kt and steepening low/midlevel lapse rates will support at least periodically organized cells, with some high-based supercell structures possible. Meager boundary-layer moisture will limit instability, resulting in transient stronger cells through the afternoon. Sporadic severe hail and strong outflow gusts will be possible as convection shifts east/northeast. Given the transient and isolated nature of any more intense convection, a watch is not expected at this time. ..Leitman/Guyer.. 10/02/2022 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...GJT...FGZ...SLC...VEF... LAT...LON 37931380 39651140 40890925 40960865 40900802 40460765 39650768 38060857 37010992 36641179 36591335 36901359 37421377 37931380 Read more

No Mesoscale Discussions are in effect as of Sun Oct 2 17:53:02 UTC 2022.

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1222 PM CDT Sun Oct 02 2022 Valid 031200Z - 041200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not forecast for Monday across the contiguous United States. ...Synopsis... A weak mid- to upper-level trough will migrate slowly east across MT/WY into the Dakotas through Tuesday morning. A surface trough will extend from the Dakotas southward into the central High Plains while high pressure influences weather conditions across much of the central and eastern U.S. Near the surface trough, a narrow plume of modest moisture (surface dewpoints in the 40s and lower 50s) and heating will yield MLCAPE around 750 J/kg from SD into NE along the wind shift, beneath relatively weak midlevel southwesterlies below 30 kt. Scattered convection is likely to form off the Front Range, producing small hail and locally gusty winds. Given the relatively dry air mass and weak low-level winds, it appears convection will be sub severe. Farther southwest in the Four Corners, primarily diurnal storm activity will result in widely scattered to scattered storms during the afternoon to early evening. ..Smith.. 10/02/2022 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1222 PM CDT Sun Oct 02 2022 Valid 031200Z - 041200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not forecast for Monday across the contiguous United States. ...Synopsis... A weak mid- to upper-level trough will migrate slowly east across MT/WY into the Dakotas through Tuesday morning. A surface trough will extend from the Dakotas southward into the central High Plains while high pressure influences weather conditions across much of the central and eastern U.S. Near the surface trough, a narrow plume of modest moisture (surface dewpoints in the 40s and lower 50s) and heating will yield MLCAPE around 750 J/kg from SD into NE along the wind shift, beneath relatively weak midlevel southwesterlies below 30 kt. Scattered convection is likely to form off the Front Range, producing small hail and locally gusty winds. Given the relatively dry air mass and weak low-level winds, it appears convection will be sub severe. Farther southwest in the Four Corners, primarily diurnal storm activity will result in widely scattered to scattered storms during the afternoon to early evening. ..Smith.. 10/02/2022 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1138 AM CDT Sun Oct 02 2022 Valid 021700Z - 031200Z Higher than expected humidity recoveries developed overnight across northern portions of the Elevated area across central Nebraska and northwestern Kansas. Higher RH and lingering clouds may limit some warming and drying through the afternoon. However, gusty southerly winds and very dry fuels may still support a few hours of locally elevated fire weather conditions across portions of the central Plains. The previous outlook remains valid with no appreciable changes. See the previous discussion. ..Lyons.. 10/02/2022 .PREV DISCUSSION... /ISSUED 0117 AM CDT Sun Oct 02 2022/ ...Synopsis... An upper low will impinge on the northern High Plains while upper ridging remains in place across the Plains States today. Surface lee troughing will encourage dry southerly flow across the Plains with the approaching of the upper low. Latest guidance consensus depicts Elevated overlapping sustained surface winds and RH for at least a few hours this afternoon across the central Plains. Elevated highlights have been introduced where fuels are at least modestly receptive to fire spread and are devoid of recent appreciable rainfall accumulations. ...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 1138 AM CDT Sun Oct 02 2022 Valid 021700Z - 031200Z Higher than expected humidity recoveries developed overnight across northern portions of the Elevated area across central Nebraska and northwestern Kansas. Higher RH and lingering clouds may limit some warming and drying through the afternoon. However, gusty southerly winds and very dry fuels may still support a few hours of locally elevated fire weather conditions across portions of the central Plains. The previous outlook remains valid with no appreciable changes. See the previous discussion. ..Lyons.. 10/02/2022 .PREV DISCUSSION... /ISSUED 0117 AM CDT Sun Oct 02 2022/ ...Synopsis... An upper low will impinge on the northern High Plains while upper ridging remains in place across the Plains States today. Surface lee troughing will encourage dry southerly flow across the Plains with the approaching of the upper low. Latest guidance consensus depicts Elevated overlapping sustained surface winds and RH for at least a few hours this afternoon across the central Plains. Elevated highlights have been introduced where fuels are at least modestly receptive to fire spread and are devoid of recent appreciable rainfall accumulations. ...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 1125 AM CDT Sun Oct 02 2022 Valid 021630Z - 031200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM UTAH/FOUR CORNERS TO THE NORTHERN HIGH PLAINS... ...SUMMARY... Isolated severe hail and wind-producing storms may occur from Utah northeastward into the northern High Plains this afternoon and early evening. ...Utah/Four Corners to northern High Plains... A closed upper low centered over southern Montana will gradually open and spread slowly eastward, with a southern peripheral belt of moderately strong westerlies over the Great Basin and central Rockies. A few areas of showers/thunderstorms are ongoing early today, but in general, relatively cloud-free skies will allow for ample early autumn heating and related boundary layer destabilization this afternoon from southern/eastern Utah into southern/eastern Wyoming and the nearby High Plains areas including the Black Hills vicinity. Destabilizing boundary layer aside, the right-entrance region of a cyclonically curved mid-level jet will influence thunderstorm development particularly across southern/eastern Utah. The strength of mid/high-level west-southwesterly winds (35+ kt effective shear) could yield some high-based supercells aside from sustained multicells. Severe hail and severe-caliber winds gusts can be expected on an isolated basis. Other storms will also increase over the mountains/interior Wyoming and move into eastern Wyoming/western South Dakota vicinity later this afternoon. Meager low-level moisture will limit CAPE and overall updraft strength. However, moderately strong winds aloft and steep lapse rates will promote gusty winds and perhaps some hail in the strongest storms. ..Guyer/Wendt.. 10/02/2022 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1125 AM CDT Sun Oct 02 2022 Valid 021630Z - 031200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM UTAH/FOUR CORNERS TO THE NORTHERN HIGH PLAINS... ...SUMMARY... Isolated severe hail and wind-producing storms may occur from Utah northeastward into the northern High Plains this afternoon and early evening. ...Utah/Four Corners to northern High Plains... A closed upper low centered over southern Montana will gradually open and spread slowly eastward, with a southern peripheral belt of moderately strong westerlies over the Great Basin and central Rockies. A few areas of showers/thunderstorms are ongoing early today, but in general, relatively cloud-free skies will allow for ample early autumn heating and related boundary layer destabilization this afternoon from southern/eastern Utah into southern/eastern Wyoming and the nearby High Plains areas including the Black Hills vicinity. Destabilizing boundary layer aside, the right-entrance region of a cyclonically curved mid-level jet will influence thunderstorm development particularly across southern/eastern Utah. The strength of mid/high-level west-southwesterly winds (35+ kt effective shear) could yield some high-based supercells aside from sustained multicells. Severe hail and severe-caliber winds gusts can be expected on an isolated basis. Other storms will also increase over the mountains/interior Wyoming and move into eastern Wyoming/western South Dakota vicinity later this afternoon. Meager low-level moisture will limit CAPE and overall updraft strength. However, moderately strong winds aloft and steep lapse rates will promote gusty winds and perhaps some hail in the strongest storms. ..Guyer/Wendt.. 10/02/2022 Read more

No watches are valid as of Sat Oct 1 17:47:02 UTC 2022.

No Mesoscale Discussions are in effect as of Sat Oct 1 17:47:02 UTC 2022.

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1217 PM CDT Sat Oct 01 2022 Valid 021200Z - 031200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated strong storms with gusty winds and small hail may occur from eastern Utah northeast into the central High Plains on Sunday, however the overall severe risk appears low. ...Synopsis... An upper-level low over the northern Rockies will lift slowly northeast Sunday while an upper trough persists along the vicinity of the east coast. In between, a ridge of high pressure will extend from the southern Plains north into the upper Midwest. Over much of the CONUS east of the Rockies, low-level moisture/instability will be lacking and thunderstorms are not expected. Available moisture coupled with diurnal heating will result in sufficient instability for thunderstorm development from Arizona northeast through the Rockies and central/northern high Plains. Cool mid-level temperatures and modestly enhanced flow associated with the upper low may result in a few stronger storms across eastern UT and western CO, and also across the central high Plains as an embedded impulse within southwesterly mid-level flow lifts northeast. Small hail and gusty winds will be possible, however weak buoyancy should limit the overall severe potential. ..Bunting.. 10/01/2022 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1109 AM CDT Sat Oct 01 2022 Valid 011630Z - 021200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE FOUR CORNERS AREA... ...SUMMARY... Isolated damaging wind gusts and hail may accompany the stronger storms across parts of the Four Corners today, including portions of southern Utah into Colorado. ...Four Corners to eastern Colorado/Wyoming... Within an amplified large-scale pattern over CONUS, a prominent closed upper low over the northern Intermountain region will tend to gradually weaken and spread slowly northward through tonight. Within its base, a belt of moderately strong cyclonic flow aloft will persist over the region. An east-northeastward pivoting vort max appears to be influencing scattered showers/thunderstorms early today across eastern Utah/western Colorado. Additional storms are expected to redevelop later this afternoon near the front across southern Utah into southwest Colorado. Despite dewpoints only in the 40s F, strong heating and steep low/mid-level lapse rates will result in weak but sufficient CAPE for a few high-based storms capable of gusty/locally damaging winds and perhaps hail. This activity will spread eastward into western Colorado later today before weakening after sunset. Farther east, a few stronger storms may also occur or persist into eastern portions of Wyoming/Colorado this afternoon. Sufficient low-level moisture and buoyancy should exist for some stronger/sustained updrafts, although modest mid-level lapse rates by Front Range/High Plains standards may temper updraft intensity a bit. While some gusty winds/small hail could occur with these mostly linear clusters, organized/sustained severe storms are not currently expected. ..Guyer/Moore.. 10/01/2022 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1051 AM CDT Sat Oct 01 2022 Valid 011700Z - 021200Z ...NO CRITICAL AREAS... Brief elevated fire weather conditions are possible east of a lee trough across portions of the High Plains this afternoon. RH values in the teens to low 20% range may temporarily overlap with sustained winds of 15 mph and higher gusts. Winds are forecast to remain gusty overnight, though humidity values should quickly recover to near 60%. Limited spatial coverage and the brevity of elevated conditions suggest low confidence in sustained elevated fire weather concerns this afternoon. ..Lyons.. 10/01/2022 .PREV DISCUSSION... /ISSUED 1237 AM CDT Sat Oct 01 2022/ ...Synopsis... A lee trough across the Central Plains will continue the dry and breezy conditions on Saturday. Corridors of elevated fire-weather conditions will be possible, mainly across western Kansas where relative humidity will drop to around 15-20 percent with sustained winds at 15-20 mph. The coverage and period of elevated fire-weather conditions. Due to this threat being brief and isolated, no critical areas are included at this time. In this area, fuels remain in the 80th to 90th percentile. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

MD 1849 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR SOUTHERN TO EASTERN UTAH AND WESTERN COLORADO
Mesoscale Discussion 1849 NWS Storm Prediction Center Norman OK 0102 PM CDT Fri Sep 30 2022 Areas affected...Southern to eastern Utah and western Colorado Concerning...Severe potential...Watch unlikely Valid 301802Z - 302000Z Probability of Watch Issuance...20 percent SUMMARY...Thunderstorms developing across southern and eastern Utah will gradually increase in intensity through the afternoon. These storms may produce strong to severe wind gusts, but will most likely remain too limited in coverage to require watch issuance. DISCUSSION...Convection across central/southern UT has shown signs of gradual intensification over the past 1-2 hours with deepening echo tops and a steady increase in lightning counts. This trend is likely being driven by a diurnal increase in buoyancy coupled with broad, but persistent lift ahead of an upper-level perturbation embedded within the circulation of the upper low over ID. As this perturbation continues to pivot east into UT, deep-layer shear will increase to around 30-40 knots and support storm organization. Modest low-level moisture will limit overall instability, but steep mid-level lapse rates (sampled by the 12 UTC SLC and GJT soundings) will support 500-1000 J/kg MUCAPE by mid/late afternoon. The low boundary-layer moisture content will also support steep low-level lapse rates where skies remain mostly clear. Latest RAP mesoanalysis estimates suggest 0-3 km lapse rates may already be as high as 8 C/km ahead of the deepening convection, which will support downdraft acceleration. A few instances of marginally severe hail are possible given the thermodynamic and somewhat elongated wind profiles, but strong to severe wind gusts will likely be the predominant hazard given the low-level thermodynamics. The isolated to scattered nature of the convection, coupled with the modulating effects of modest buoyancy, should limit the overall severe potential and the need for a watch this afternoon. ..Moore/Bunting.. 09/30/2022 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...GJT...SLC... LAT...LON 39121095 39771010 40030929 39950858 39600806 38760768 37700816 37430902 37181051 37141166 37111248 37851264 38331214 39121095 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1203 PM CDT Fri Sep 30 2022 Valid 011200Z - 021200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The severe-thunderstorm threat is expected to remain low on Saturday. ...Synopsis... The remnants of Ian are forecast to drift north/northeast on Saturday across western/central NC/VA toward the Chesapeake Bay vicinity. While moderate low-level winds and vertical shear will reside over the region, limited heating due to cloud cover and widespread precipitation will limit destabilization. Any stronger surface-based instability is expected to remain offshore the Mid-Atlantic coast through the period, limiting tornado potential across the Delmarva region. To the west, an upper low will meander over ID/WY/MT, while an upper ridge remains oriented from the lower MO Valley into the central/southern Plains. Several mid/upper shortwave impulses will rotate around the western upper low in the vicinity of the central/northern high Plains. Southeasterly upslope low-level winds will transport modest boundary-layer moisture northward into northeast CO into western NE. Stronger heating will reside to the east of this meager moist axis, but some weak destabilization will occur, aided by steep midlevel lapse rates. Modest vertical shear and weak instability should limit thunderstorm organization/intensity and overall severe potential, though some gusty outflow winds will be possible. ..Leitman.. 09/30/2022 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1139 AM CDT Fri Sep 30 2022 Valid 301700Z - 011200Z The previous forecast remains valid with only minor expansion of the Elevated area farther north based on the latest guidance. Elevated to locally critical fire weather concerns will be possible with gusty winds and dry surface conditions near a lee trough this afternoon. Please see the previous discussion for more information. ..Lyons.. 09/30/2022 .PREV DISCUSSION... /ISSUED 1257 AM CDT Fri Sep 30 2022/ ...Synopsis... An upper level low will continue a gradual shift southward across the northern Rockies through the day on Friday. A surface low will deepen across the Central Plains with dry and windy conditions aiding in the potential for spread of any new fires that develop. ...Central Plains and Southeastern California... As the surface low deepens across the Central Plains, increased surface pressure gradients may result in increased south to southwesterly flow around 15-20 mph. Elevated fire-weather conditions will spread across the Central Plains as afternoon minimum relative humidity around 15-20 percent across the Texas and Oklahoma Panhandles. Elevated conditions will stretch as far north as western Kansas and southeastern Colorado. A few stations across western Kansas may briefly approach critical fire-weather conditions with relative humidity dropping to 15% and sustained winds at 20 mph. ERCs across the Central Plains into eastern Colorado remain in the 80-90th percentile. ...Please see www.spc.noaa.gov/fire for graphic product... Read more