Severe Storms

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1220 PM CDT Wed Sep 14 2022 Valid 151200Z - 161200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE SOUTHERN AND CENTRAL PLAINS... ...SUMMARY... Isolated to widely scattered high-based storms capable of damaging wind gusts are possible from the Texas Panhandle, to central Kansas, and into central/eastern Nebraska Thursday. ...Southern and central Plains... Broad troughing across the western US is forecast to continue through Thursday as high pressure shifts eastward. Embedded within the broader trough, a subtle shortwave is expected to move over the southern and central Plains Thursday afternoon and evening. Trailing from a weak surface low across the Dakotas, a lee trough/low will support increasing southerly flow across much of the Plains. Modest moisture return (surface dewpoints in the 50s to low 60s F) will filter westward toward the surface boundary where plentiful diurnal heating is expected. Storms will be possible along the entire corridor from NE into the TX Panhandle, though there remains some uncertainty on convective coverage given the subtle forcing for ascent. Current hi-res guidance suggests the greatest storm coverage will remain closer to the surface low across central and eastern NE, where low-level flow is expected to be locally stronger. By early to mid afternoon, convective development along the length of the lee trough is expected. With only modest surface moisture return forecast, regional model soundings show weak buoyancy profiles generally less than 1000 J/kg of MLCAPE. Modest flow aloft associated with the shortwave trough should also limit effective shear to 20-25 kt. Storm organization potential will likely remain localized and tied to consolidating outflow/clustering of any multi-cell storms that persist. Should this occur, a well-mixed boundary layer with steep low-level lapse rates and LCLs near 2 km may support an isolated risk for damaging outflow winds given the potential for stronger downdrafts. ...Rest of US... Scattered to numerous thunderstorms are also anticipated across the FL Peninsula, as a moist low-level airmass interacts with a weak stationary front across the region. Weak vertical shear will keep storms unorganized with only locally stronger wind gusts expected. Isolated to scattered thunderstorms are also expected across the northern Rockies and Great Basin, ahead of a low-amplitude shortwave trough over the western CONUS. Limited buoyancy and shear should preclude severe storms. ..Lyons/Jewell.. 09/14/2022 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1053 AM CDT Wed Sep 14 2022 Valid 141630Z - 151200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND EVENING OVER PORTIONS OF THE SOUTHERN HIGH PLAINS... ...SUMMARY... Storms capable of isolated severe gusts will be possible this afternoon and evening over portions of the southern High Plains. ...Southern High Plains... A weak/broad trough is present today over the western US, with weak but cyclonic flow across the southern High Plains. Strong heating over the higher terrain of eastern NM will lead to scattered thunderstorms by late afternoon, spreading slowly eastward into west TX. Winds aloft are rather weak, but steep low-level lapse rates and CAM solutions of growing clusters of storms may result in localized gusty/damaging winds for a few hours this evening. ..Hart/Moore.. 09/14/2022 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1050 AM CDT Wed Sep 14 2022 Valid 141700Z - 151200Z ...NO CRITICAL AREAS... The previous forecast remains on track. The latest guidance consensus suggests that a couple of hours of widespread Elevated conditions may occur across western Nebraska into far northwest Kansas. However, clouds and occasional showers will continue to overspread the central Plains through the day, with potentially heavier rains possible through Day 2/tomorrow. As such, significant wildfire-spread potential should be somewhat limited, precluding the addition of any fire weather highlights. ..Squitieri.. 09/14/2022 .PREV DISCUSSION... /ISSUED 0138 AM CDT Wed Sep 14 2022/ ...Synopsis... A large-scale ridge will remain centered over the MS Valley, while broad midlevel troughing and enhanced west-southwesterly flow aloft persist over the western states. Embedded within the west-southwesterly flow, a series of low-amplitude shortwave troughs will cross the Rockies, reinforcing a surface lee trough over the northern and central High Plains. ...Central High Plains... Southerly surface winds will strengthen across the Plains in response to the deepening lee trough. At the same time, increasing boundary-layer moisture and scattered to broken mid/high-level clouds may limit RH reductions where the breezy winds are expected. Despite the marginal RH reductions, 20-25 mph sustained southerly surface winds (with 30-35 mph gusts) could yield locally elevated fire-weather conditions during the late morning/early afternoon hours. This will especially be the case over parts of northeast CO, northwest KS, and southwest NE -- where pockets of 25 percent minimum RH will be possible prior to the development of showers and storms. With that said, the aforementioned cloud coverage, widely scattered showers and storms, and marginal fuels cast uncertainty on the overall fire-weather threat -- precluding Elevated highlights at this time. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

No watches are valid as of Tue Sep 13 18:01:02 UTC 2022.

No Mesoscale Discussions are in effect as of Tue Sep 13 18:01:02 UTC 2022.

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1212 PM CDT Tue Sep 13 2022 Valid 141200Z - 151200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Scattered to numerous thunderstorms are possible across the Florida Peninsula as well as over the Great Basin and central Rockies Wednesday. A few thunderstorms are also possible across the northern Plains Wednesday afternoon into early Thursday morning. Severe-thunderstorm potential is low. ...Western and central US... Broad mid-level troughing across the western US is forecast to move eastward as high pressure over the central Plains weakens and shifts south. Ahead of the trough, lee cyclogenesis is expected over the western Dakotas with broad southerly flow likely over the Plains. In the wake of the previous cold front, deep surface moisture will be slow to return. However, increasing mid-level tropical moisture associated with the western us trough will support several areas of scattered to numerous thunderstorms across the Great Basin and central Rockies, onto the Plains. Convective coverage is expected to remain the greatest farther west where orographic lift and mid-level moisture will be best aligned. Mid-level flow is expected to remain modest keeping vertical shear low and storm organization potential low. Across the Plains, the more limited moisture will support lesser storm coverage, with the best chances expected near the surface low across the eastern Dakotas. Here only a few storms are expected, with limited severe potential from marginal buoyancy and shear. ...Florida... South of a stalled cold front, a seasonably warm and moist airmass will support scattered to numerous thunderstorms across the Peninsula Wednesday afternoon. In the absence of stronger forcing for ascent, primary lift for thunderstorms will be local and tied to sea-breeze interactions. A few stronger multi-cell clusters may emerge as convective outflow consolidates later in the afternoon. However, the lack of vertical shear and stronger forcing should keep any storm organization and severe potential short lived and minimal. ..Lyons/Jewell.. 09/13/2022 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1109 AM CDT Tue Sep 13 2022 Valid 131630Z - 141200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NEW ENGLAND REGION... ...SUMMARY... Thunderstorms capable of damaging wind gusts, isolated hail and a brief tornado or two are possible today from eastern New York into parts of New England, mainly this afternoon into the early evening. ...Synopsis... An upper-level low over Lake Erie will gradually shift east/northeast through the day into the northeastern CONUS. As this occurs, a weak surface low will undergo some deepening as it moves northeast across the New England region. A trailing cold front, analyzed in latest surface observations from central NY southward along the East Coast, will focus thunderstorm development through the afternoon and evening hours. Across the western U.S., an upper-level trough over the Great Basin will phase with a shortwave disturbance moving into the Pacific Northwest. Ample moisture and lift ahead of these features will support scattered thunderstorm development across a broad swath of the inter-mountain West. A few strong wind gusts and marginally severe hail are possible with this activity, especially across portions of AZ/NM where deeper boundary-layer mixing is expected, but marginal wind profiles will limit the potential for widespread organized convection. ...New England... Thunderstorm development along the cold front is already underway at 16 UTC across parts of central NY. The 12 UTC ALB sounding sampled poor low and mid-level lapse rates, but ample moisture throughout the profile. Extensive cloud cover will likely limit the influence of daytime heating, but most model solutions suggest that only modest diurnal warming into the mid 70s is needed to support surface-based parcels with minimal inhibition and 500-1500 J/kg SBCAPE. Overall buoyancy magnitudes may be modulated by the poor mid-level lapse rates, and should generally decrease with northwestward extent away from the coast and the higher-quality moisture. The approach of the upper wave through the day will strengthen mid to upper-level winds and elongate hodographs. Nearly straight hodographs featuring effective bulk shear values near 35-45 knots will support storm organization, including the potential for supercell or two. Low-level flow is expected to remain fairly weak below 2-3 km, but may exhibit sufficient curvature to support low-level rotation and a brief/weak tornado threat. ..Moore/Hart.. 09/13/2022 Read more

No Mesoscale Discussions are in effect as of Mon Sep 12 17:55:02 UTC 2022.

No watches are valid as of Mon Sep 12 17:55:02 UTC 2022.

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1212 PM CDT Mon Sep 12 2022 Valid 131200Z - 141200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF NEW ENGLAND AND THE NORTHEAST... ...SUMMARY... Isolated severe thunderstorms capable of damaging wind gusts and a brief weak tornado are possible across New England on Tuesday. ...Northeastern CONUS and New England... A compact upper low over the northern OH Valley and Great Lakes will transition to an open wave early Tuesday, as it is re-absorbed into stronger westerly flow over the northeastern CONUS. A moderate H5 jet along the southern periphery of the wave will spread dynamic lift eastward through much of Tuesday morning. At the surface, an occluded cyclone over the northern Great Lakes will slowly fill as a secondary surface low over southern ON/QC deepens and draws 60s and 70s F surface dewpoints northward. A cold front associated with the new surface low will strengthen as it shifts eastward, providing the main impetus for strong to severe storms Tuesday afternoon. With persistent lift from the upper low and jet streak overspreading the region early, widespread cloud cover and precipitation are expected Tuesday morning. Regional model soundings show deep saturated surface layers with dewpoints in the upper 60s to low 70s F. Buoyancy is expected to be weak owing to widespread cloud cover and poor mid-level lapse rates, but modest destabilization (MLCAPE ~500 J/kg) is still possible given the degree of low-level moistening. Deep-layer vertical shear of 40-50 kt will be favorable for organized storms with the upper jet overhead. While the strong frontal forcing will favor a more linear band of convection with northern extent, a pre-frontal supercell or two is possible across southern New England. Confidence in severe storm development is relatively low given the potential for early morning storms delaying destabilization. High-res guidance shows the most coverage of potential strong/severe storms along the cold front closer to the surface low across upstate NY, VT and NH. Here, the primary risk will be isolated damaging wind gusts given the moderate low and mid-level wind fields. Damaging gusts and a brief/weak tornado will be also be possible farther south across CT/RI/MA where greater backed surface flow may locally enhance low-level shear. However, this is conditional upon any supercells able to evolve ahead of the main cold front. ...Southwest/Great Basin/Intermountain West... The remains of Tropical Cyclone Kay will progress eastward across the Great Basin towards the northern/central Rockies as a remnant trough Tuesday. Lift and moisture attendant to this system will result in widespread thunderstorms, with the highest storm coverage anticipated over northern AZ and northwest NM. Weak buoyancy and vertical shear within the modified tropical airmass should serve to limit the overall severe potential. ..Lyons/Gleason.. 09/12/2022 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1118 AM CDT Mon Sep 12 2022 Valid 121630Z - 131200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE MID-ATLANTIC AND SOUTHERN TO CENTRAL ARIZONA... ...SUMMARY... Isolated strong to severe thunderstorms may occur across parts of the Mid-Atlantic and Northeast, and over portions of Arizona. ...Synopsis... A surface cold front, recently analyzed from the upper OH River Valley into the lower MS River Valley, will continue to push east into the Northeast, Mid-Atlantic, and Southeast Coast over the next 24 hours. Aloft, an upper trough has begun to slowly migrate east, which will resulting in modest surface pressure falls along/ahead of the front across the Mid-Atlantic region this evening. The eastward progression of the wave and the slight deepening of the low will result in increasing shear that may support organized convection as thunderstorms develop along and just ahead of the front. Across the Southwest, an upper low will continue to meander off the coast of southern California. A persistent influx of unseasonably high moisture into AZ will support thunderstorm development off the terrain of southern/southeast AZ. ...Mid-Atlantic... Early morning fog/low stratus is quickly mixing out across VA/MD, allowing temperatures to warm into the upper 70s and low 80s from the Carolinas into north-central MD. These temperatures are warmer than expected by most guidance by 16 UTC, suggesting that surface-based instability and low-level lapse rates may be higher/steeper than indicated by morning model runs. Despite the clearing skies, poor low and mid-level lapse rates sampled by 12 UTC soundings will likely limit overall buoyancy values to near 1000 J/kg MLCAPE this afternoon. Combined with increasing deep-layer shear, a few strong to severe storms are expected along the front. Semi-organized clusters and/or linear segments will pose a damaging wind threat, and any discrete cells may acquire sufficient organization to pose a hail and brief/weak tornado threat. ...Arizona... Thunderstorm development off the Mogollon Rim and the Chiricahua/Pinaleno mountains is expected by late afternoon amid a persistent influx of unseasonably high low-level moisture (dewpoint values in the upper 60s are near the 90th percentile for mid-September). Despite modest flow aloft, ample daytime heating will promote steep low-level lapse rates/deep boundary-layer mixing favorable for a few strong to severe gusts as convection propagates off the terrain. ..Moore/Hart.. 09/12/2022 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1035 AM CDT Mon Sep 12 2022 Valid 121700Z - 131200Z The previous forecast remains on track, with only minor changes made to the isolated dry thunderstorm highlights to reflect the latest guidance consensus. Please see the previous forecast below for more details. ..Squitieri.. 09/12/2022 .PREV DISCUSSION... /ISSUED 0156 AM CDT Mon Sep 12 2022/ ...Synopsis... The northwestern periphery of an amplified large-scale ridge centered over the western states will break down in response to an eastward-advancing midlevel trough over the Pacific Northwest. At the surface, low pressure will track east-northeastward from SK into ON Canada, while a trailing cold front sweeps southward across the northern Plains. ...Dry Thunderstorms... Preceding the midlevel trough over the Pacific Northwest, an embedded shortwave impulse will track northeastward across the northern Great Basin. As strengthening large-scale ascent accompanying this feature overspreads a plume of midlevel moisture emanating from the eastern Pacific, isolated to widely scattered high-based thunderstorms should develop. Deep boundary-layer mixing beneath the midlevel moisture will result in inverted-V thermodynamic profiles -- supporting dry thunderstorms initially. Given receptive fuels over the northern Great Basin, isolated lightning-induced ignitions will be possible -- especially during the early stages of storm development and away from any heavier precipitation cores. Strong/erratic outflow winds could also develop with the more robust storms. ...Northern Plains... Behind the southward-advancing cold front over the northern Plains, breezy northerly surface winds near 15 mph will be possible. Those, coupled with 15-20 percent RH, will favor elevated fire-weather conditions over eastern MT, western ND, and far northwestern SD during the afternoon/early evening hours. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

No watches are valid as of Sun Sep 11 17:53:01 UTC 2022.

No Mesoscale Discussions are in effect as of Sun Sep 11 17:53:01 UTC 2022.

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 PM CDT Sun Sep 11 2022 Valid 121200Z - 131200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MID-ATLANTIC INTO NORTH CAROLINA...AND PORTIONS OF ARIZONA... ...SUMMARY... Isolated strong to severe thunderstorms may occur across parts of the Mid-Atlantic into North Carolina on Monday, with occasional damaging winds the main threat. A few severe thunderstorms also appear possible across portions of Arizona. ...Mid-Atlantic into North Carolina... A closed mid/upper-level cyclone will be present over the Midwest and Great Lakes on Monday. This feature is forecast to advance slowly eastward across these regions through the period. At the surface, a weak low initially over southern WI/northern IL should further occlude as it develops eastward across the Great Lakes and OH Valley through Monday evening. A cold front should move east-southeastward across much of the eastern CONUS and Southeast. A moist low-level airmass is expected to be in place ahead of the front across much of the Mid-Atlantic and Southeast. Due to occluded nature of the cyclone, mid-level lapse rates should generally remain poor across the warm sector. Even so, daytime heating is forecast to aid in the development of weak to locally moderate instability, with MLCAPE increasing into the 1000-2000 J/kg range by Monday afternoon. Thunderstorms should gradually develop through the day both along the surface cold front and ahead of it along weak low-level confluence bands. The best potential for robust convection appears to extend across portions of PA/NJ southward into MD/DE/VA and NC. This region should have some enhancement to mid-level southwesterly winds, even with the strongest flow aloft forecast to generally lag behind the cold front across the OH Valley. It appears that around 25-35 kt of deep-layer shear will be present to support updraft organization. Multicell clusters capable of producing isolated strong to damaging winds should be the main severe threat as they spread eastward through Monday evening. Where the deep-layer shear is forecast to be strongest (VA/MD/DC vicinity), marginal supercells may occur and pose a threat for both isolated hail and perhaps a brief tornado. ...Arizona... The remnants of a tropical cyclone should spread northward from southern CA into the Great Basin on Monday. A belt of modestly enhanced mid-level southerly flow is expected to be in place between this feature and upper ridging centered over the Four Corners. A rather moist low-level airmass should be present over the lower elevations of AZ. Diurnal heating of this airmass and persistent southerly mid-level flow should aid in the development of scattered to numerous thunderstorms Monday afternoon and evening across parts of southeastern into central and northern AZ. Although deep-layer shear appears marginal for thunderstorm organization, some clustering may occur. Isolated severe wind gusts appear possible with any thunderstorms that can develop as low-level lapse rates steepen. Occasional hail may also occur with the strongest cores. ..Gleason.. 09/11/2022 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1103 AM CDT Sun Sep 11 2022 Valid 111630Z - 121200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe-thunderstorm potential appears minimal today and tonight. ...Synopsis... Mid-morning surface observations and satellite imagery clearly show the east/southeastward progression of a cold front into the MS River Valley. Modest cold advection following this front will continue to drive weak height falls aloft over the central CONUS over the next 24 hours, leading to a gradual deepening of the upper wave over the Midwest. Surface analyses also show the front surging relatively faster across the lower MS River Valley/eastern southern Plains compared to locations closer to the surface low over southern Lake Michigan. This suggests that the occlusion process has likely begun and will continue through the day. Despite this, the amplification of the upper air regime will support gradual deepening of the nearly stationary surface low over northeast IL through tonight. Thunderstorms have already begun to develop along the cold front, and will expand in coverage through the afternoon hours as the front pushes east through the OH Valley region. Across the northern Gulf coast, a decaying cut-off low will migrate east/northeast through the day. Ample moisture advection associated with this feature combined with weak/broad ascent and areas of daytime heating/surface-based destabilization will support another day of scattered thunderstorms from FL northward to the Mid-Atlantic coast. Unseasonably high moisture associated with the remnants of Tropical Storm Kay will continue to foster thunderstorm chances across a broad area of the Southwest today. Stronger wind gusts are possible with any thunderstorm moving into a well-mixed region, but weak flow aloft will limit the probability of numerous severe gusts. ...Middle OH River Valley.. Morning RAOBs ahead of the cold front across the OH River Valley show ample boundary-layer moisture, but weak low and mid-level lapse rates. Extensive cloud cover will likely hinder surface-based destabilization for much of the day. However, evidence of elevated instability with limited inhibition is noted in observed and forecast soundings, as well as latest satellite trends. The deepening of the upper low will support increasing flow and elongating hodographs above 3 km through the day, which may provide adequate effective shear for a few stronger, more organized cells or clusters. If storms can become rooted within the boundary, a few strong wind gusts may occur. This will be most likely for areas that can see surface temperatures warm through the mid/upper 70s, but confidence in a sufficiently widespread severe risk remains too limited to introduce probabilities. ..Moore/Hart.. 09/11/2022 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1035 AM CDT Sun Sep 11 2022 Valid 111700Z - 121200Z ...NO CRITICAL AREAS... The previous forecast (see below) remains on track, with no changes or additions made. ..Squitieri.. 09/11/2022 .PREV DISCUSSION... /ISSUED 0149 AM CDT Sun Sep 11 2022/ ...Synopsis... An expansive mid/upper-level ridge will encompass the western CONUS, while a belt of moderate westerly midlevel flow crosses the northern Rockies along the northern periphery of the ridge. As the enhanced westerly midlevel flow intercepts the Lewis Range in northern MT, 10-15 mph sustained surface winds amid 10-15 percent RH could lead to locally elevated conditions. However, current indications are that fuels are only receptive on a spotty basis owing to recent precipitation -- precluding Elevated highlights. Elsewhere, a minimal overlap of strong winds and low RH should generally limit the fire-weather risk outside of terrain-favored areas along the Cascades. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

No watches are valid as of Sat Sep 10 17:56:01 UTC 2022.

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1206 PM CDT Sat Sep 10 2022 Valid 111200Z - 121200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A few stronger thunderstorms are possible across the Ohio Valley, Lower Colorado River Valley, and the Florida Big Bend to southeast Virginia region Sunday morning into early Monday morning. Severe thunderstorm potential is low. ...Mid-MS/OH Valley Vicinity... An upper low is expected to develop Sunday as an early morning shortwave trough over the lower MO Valley spreads eastward across the Mid-MS/Lower OH Valley vicinity. This will result in modest vertical shear across the region as mid/upper flow increases. At the surface, a moist airmass will be in place ahead of an eastward-advancing cold front across parts of IL/IN/OH/KY. Widespread cloud cover and ongoing showers/thunderstorms will limit heating. Furthermore, low/midlevel lapse rates will remain poor. Together, this will limit stronger instability from developing, with around 500-750 J/kg MLCAPE forecast. Some locally gusty winds may accompany stronger storms within clusters or line segments, but overall severe potential is expected to remain low. ...FL Big Bend to the Coastal Carolinas/Southeast VA... A weakening shortwave trough over the Lower MS Valley will spread eastward across the southeastern U.S. Vertical shear will remain weak across the region, with some modest enhancement of mid/upper southwesterly flow. Nevertheless, a very moist airmass will be in place, with afternoon temperatures warming into the upper 70s to upper 80s, supporting weak destabilization. Organized severe storms are expected to remain limited by modest instability and poor lapse rates, but locally strong gusts could occur, aided by water-loaded downdrafts in thunderstorm clusters. ...Southern CA into AZ... The remnants of TC Kay will continue to impact the region, with increased low and midlevel moisture persisting across southern CA into AZ/NM. This will support isolated thunderstorm development, especially near higher terrain. The greatest thunderstorm coverage will likely be across parts of the higher terrain of AZ into west-central NM. A few locally strong gusts could accompany this activity if storms can persist as they move off the higher terrain into the lower deserts where steep low level lapse rates are expected. Even so, warm temperatures aloft and modest vertical shear will limit overall severe potential. ..Leitman.. 09/10/2022 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CDT Sat Sep 10 2022 Valid 101630Z - 111200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE SOUTHEAST AND DESERT SOUTHWEST STATES.... ...SUMMARY... Isolated, marginally severe convective gusts, or a brief tornado, may occur over parts of the southeast states, and the desert southwest. ...Southeast... A persistent upper low remains over LA today, with a plume of deep, moist southerly flow across much of the southeast states. Widespread showers and thunderstorms have been occurring this morning over the eastern Gulf of Mexico. This activity will spread inland this afternoon and affect much of FL/GA. Other more isolated storms will affect parts of the Carolinas this afternoon. Wind fields are modest, but ample moisture and localized enhancements to shear may result in locally damaging wind gusts or perhaps a tornado or two. Refer to MCDs #1773 and #1774 for further small-scale details. ...NV/CA... A band of relatively strong easterly mid-level winds extends across northern AZ into southern NV today. Most 12z CAM guidance shows increasing thunderstorm activity along this corridor this afternoon. Forecast soundings show unusually high PWAT values, promoting a risk of gusty/damaging wind gusts in the strongest cells. The area of highest threat appears to extend from northern Death Valley into the deserts of southwest NV. ..Hart/Moore.. 09/10/2022 Read more