Severe Storms

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0744 PM CDT Wed Oct 11 2023 Valid 120100Z - 121200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER MUCH OF CENTRAL AND WESTERN FLORIDA TOWARD THE COASTAL BEND... ...SUMMARY... Damaging thunderstorm gusts and a few tornadoes are possible this evening and tonight over the western Florida Peninsula/coastal-bend region. Strong to severe thunderstorms over the central Plains and Midwest may be capable of marginal hail through late tonight. ...Much of the western FL Peninsula to the coastal FL Panhandle... A front currently extends across north-central FL, with cool and relatively stable air to the north. The 00Z JAX sounding shows poor lapse rates and no instability within this air mass. The TLH exhibits similar characteristics, north of the boundary. South of these areas, and where winds have a southerly component, upper 70s F dewpoints are contributing to modest instability, ahead of the developing areas of storms over the Gulf of Mexico. Shear profiles are strengthening across the entire area in anticipation of the approaching convectively enhanced low, and a few supercells perhaps with tornado risk will conditionally be possible with any storms that move ashore. This appears most likely late tonight from the Coastal Bend southeastward toward the Tampa Bay area as stronger instability develops with time. ...From NE into northern IL... The 00Z LBF sounding shows nearly 1000 J/kg MLCAPE present, with steep lapse rates aloft. Meanwhile, showers and thunderstorms currently extend from the western Panhandle into northeast CO. As the surface low deepens and low-level theta-e advection persists with backed boundary-layer winds, conditions should remain favorable for scattered storms to develop, with some likely producing hail. Large-scale ascent will remain favorable, with increasing storm coverage likely later this evening. Effective shear appears to further favor cellular storm modes which will be favorable for hail. Isolated strong gusts may also occur in proximity to the warm surface air near the warm front. ..Jewell.. 10/12/2023 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0754 PM CDT Tue Oct 10 2023 Valid 110100Z - 111200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected through tonight. Scattered storms are expected to develop later tonight over parts of the middle and lower Missouri Valley. Non-severe, diurnally driven storms over western TX are expected to wane this evening as the boundary layer cools. To the northeast, a band of elevated convection is forecast after 06Z from southeast NE into MO, in association with increasing theta-e advection with southwest 850 mb flow to 40 kt. Forecast soundings show cool midlevel temperatures, but overall marginal instability to support any hail over 1.00" diameter. While initial development could exhibit robust updrafts, effective shear does not appear to support anything long-lived enough to produce severe weather. ..Jewell.. 10/11/2023 Read more

No watches are valid as of Wed Oct 11 00:59:01 UTC 2023.

No Mesoscale Discussions are in effect as of Wed Oct 11 00:59:01 UTC 2023.

No watches are valid as of Tue Oct 10 23:49:02 UTC 2023.

No Mesoscale Discussions are in effect as of Tue Oct 10 23:49:02 UTC 2023.

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0307 PM CDT Tue Oct 10 2023 Valid 121200Z - 181200Z The period will begin with a mid-level trough ejecting from the Rockies and impinging on the Mississippi Valley late this week into the weekend, encouraging strong surface cyclone development across the central Plains. Trailing this cyclone will be a surface dryline and cold front, accompanied by dry and windy conditions across portions of the southern High Plains. 40 percent critical probabilities have been maintained across portions of the southern High Plains Day 3/Thursday, where confidence is highest in at least Elevated-equivalent dry and windy conditions occurring. High pressure building over the Interior West will encourage the strengthening of a surface pressure gradient over southern California on Thursday, supporting dry offshore flow, warranting the introduction of 40 percent Critical probabilities. For Friday into Saturday, the cold front and accompanying dry and breezy conditions will overspread portions of western Texas into the Lower Mississippi Valley. However, confidence in long-duration dry and windy conditions is low, with Critical probabilities withheld. After Saturday, surface high pressure and cooler surface temperatures will overspread much of the central and western CONUS, limiting significant wildfire-spread concerns. ..Squitieri.. 10/10/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0307 PM CDT Tue Oct 10 2023 Valid 121200Z - 181200Z The period will begin with a mid-level trough ejecting from the Rockies and impinging on the Mississippi Valley late this week into the weekend, encouraging strong surface cyclone development across the central Plains. Trailing this cyclone will be a surface dryline and cold front, accompanied by dry and windy conditions across portions of the southern High Plains. 40 percent critical probabilities have been maintained across portions of the southern High Plains Day 3/Thursday, where confidence is highest in at least Elevated-equivalent dry and windy conditions occurring. High pressure building over the Interior West will encourage the strengthening of a surface pressure gradient over southern California on Thursday, supporting dry offshore flow, warranting the introduction of 40 percent Critical probabilities. For Friday into Saturday, the cold front and accompanying dry and breezy conditions will overspread portions of western Texas into the Lower Mississippi Valley. However, confidence in long-duration dry and windy conditions is low, with Critical probabilities withheld. After Saturday, surface high pressure and cooler surface temperatures will overspread much of the central and western CONUS, limiting significant wildfire-spread concerns. ..Squitieri.. 10/10/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0307 PM CDT Tue Oct 10 2023 Valid 121200Z - 181200Z The period will begin with a mid-level trough ejecting from the Rockies and impinging on the Mississippi Valley late this week into the weekend, encouraging strong surface cyclone development across the central Plains. Trailing this cyclone will be a surface dryline and cold front, accompanied by dry and windy conditions across portions of the southern High Plains. 40 percent critical probabilities have been maintained across portions of the southern High Plains Day 3/Thursday, where confidence is highest in at least Elevated-equivalent dry and windy conditions occurring. High pressure building over the Interior West will encourage the strengthening of a surface pressure gradient over southern California on Thursday, supporting dry offshore flow, warranting the introduction of 40 percent Critical probabilities. For Friday into Saturday, the cold front and accompanying dry and breezy conditions will overspread portions of western Texas into the Lower Mississippi Valley. However, confidence in long-duration dry and windy conditions is low, with Critical probabilities withheld. After Saturday, surface high pressure and cooler surface temperatures will overspread much of the central and western CONUS, limiting significant wildfire-spread concerns. ..Squitieri.. 10/10/2023 ...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 0238 PM CDT Tue Oct 10 2023 Valid 102000Z - 111200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected through tonight. ...20z Update... No changes have been made to the outlook with the 20z update, and severe storms are not expected through tonight. ..Leitman.. 10/10/2023 .PREV DISCUSSION... /ISSUED 1108 AM CDT Tue Oct 10 2023/ ...Synopsis... Thunderstorm potential today/tonight will be primarily influenced by the deepening of an upper wave (noted off the Pacific Northwest coast in morning satellite imagery) as it moves into the inter-mountain West over the next 24 hours. ...Pacific Northwest to the Southern High Plains... Across the Pacific Northwest and northern Rockies, cooling temperatures aloft combined with strong dynamic ascent within the left-exit region of the attendant upper jet will support widespread rainfall with embedded convection through tomorrow morning. Along the OR/WA coasts, latest satellite imagery depicts cooler/drier air aloft moving onshore, which should bolster low to mid-level buoyancy through the day. While some low-level shear is noted in coastal forecast soundings, hodograph structure through tonight is forecast to remain somewhat poor with 0-1 km SRH values sub-100 m2/s2. Combined with a transient convective signal in latest CAM guidance, the coastal tornado potential remains too limited to introduce probabilities. Steep mid-level lapse rates and residual mid-level moisture sampled by 12 UTC soundings from the northern Great Basin into the Southwest may support very isolated thunderstorms through the afternoon from southern WY to northern NM amid continued mid-level height falls. However, the broad-scale nature of the ascent combined with very low PWAT values suggests any convection should be fairly isolated and short lived. Additionally, a lack of a convective signal in any 12 UTC guidance limits confidence in thunder occurrence and coverage outside of southwest CO where a relatively stronger convective signal is noted in HREF thunder probabilities. Thunderstorm potential is higher across the southern High Plains where weak moisture return is coincident with steady surface pressure falls. ...Kansas/Missouri... A weak band of isentropic ascent in the 850-700 mb layer should continue to support occasional lighting flashes across central/eastern KS this afternoon. A strengthening low-level jet will bolster thunderstorm coverage and intensity across northern MO later tonight. Deep-layer shear values may approach 25-30 knots and could foster some storm organization. Small hail is possible with stronger cells across northwest MO, but storm interactions/clustering should limit the overall severe threat. ...South Texas/South Florida... Isolated thunderstorms are possible across the southern FL Panhandle within a stalled, frontolytic cold front, but limited buoyancy and weak forcing for ascent should preclude a severe threat. Likewise, marginal buoyancy profiles across south TX should support lightning as a tropical low deepens over the western Gulf of Mexico later tonight, but the severe potential remains low. Read more

No watches are valid as of Mon Oct 9 23:16:01 UTC 2023.

No Mesoscale Discussions are in effect as of Mon Oct 9 23:16:01 UTC 2023.

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0318 PM CDT Mon Oct 09 2023 Valid 111200Z - 171200Z A mid-level trough will amplify over the central Rockies and eject into the Plains states during the Days 3-5/Wednesday-Friday period, supporting the deepening of a surface cyclone over the central High Plains. From Wednesday-Friday, the mid-level trough and surface cyclone will shift eastward toward the MS Valley, with strong, dry westerly surface winds expected in the post-cold front/dryline environment. While fuels are marginally receptive to fire spread overall, fuels appear more locally receptive across portions of central New Mexico, into far western Texas, eastern Colorado, and western Kansas. 40 percent critical probabilities have been added Days 3-4/Wednesday-Thursday for areas that should experience the best overlap of dry/windy surface conditions and relatively more receptive fuels. By late this week through the weekend, surface high pressure and associated cooler temperatures will overspread much of the central and southern CONUS, limiting significant wildfire-spread potential. ..Squitieri.. 10/09/2023 ...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 0252 PM CDT Mon Oct 09 2023 Valid 092000Z - 101200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected through tonight. ...20Z Update... No changes needed to the ongoing forecast. See previous outlook appended below for more forecast details. ..Mosier.. 10/09/2023 .PREV DISCUSSION... /ISSUED 1100 AM CDT Mon Oct 09 2023/ ...Synopsis... Mid-morning surface observations continue to depict cool and dry conditions across a majority of the country. The broad northwest flow regime over the eastern two-thirds of the CONUS will limit thunderstorm potential and maintain quiescent conditions with the exception of a few regions. Lingering low/mid-level moisture over the Southwest and steep mid-level lapse rates will foster another day of orographically-driven thunderstorms. Weak moisture return into the southern High Plains may support isolated thunderstorms across parts of CO, NM, and the OK/TX Panhandles late this afternoon. Deep boundary-layer mixing may support a few strong downbursts, but confidence in the potential for severe wind is too limited for probabilities. Isolated thunderstorms are also possible this evening/later tonight across the northern Great Basin/northern Rockies as ascent associated with an approaching upper wave overspreads the region. Across the southern FL Panhandle, a few thunderstorms are possible along/south of a stalled frontal boundary. 30-40 knot mid-level flow may support transient storm organization with sufficiently deep/mature convection, but as with previous days, forcing for ascent will likely be too weak/nebulous to support a substantial severe threat over land. Read more

No Mesoscale Discussions are in effect as of Sun Oct 8 22:36:02 UTC 2023.

No watches are valid as of Sun Oct 8 22:36:02 UTC 2023.

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0351 PM CDT Sun Oct 08 2023 Valid 101200Z - 161200Z A mid-level trough is expected to eject into the Atlantic Ocean early this week as a second mid-level trough amplifies over the Interior West and ejects into the Plains states/Mississippi Valley during the mid to late part of the week. As this occurs, strong surface cyclone development is expected across the Plains states, accompanied by ample southerly moisture return. As the trough shunts eastward toward the Appalachian mountains, a surface cold front will sweep across the central U.S., reinforced by high pressure and cooler/dry air. In the immediate post cold front/dryline environment, dry and windy conditions may prevail across the southern High Plains into central Texas during the Days 5-6/Thursday-Friday period. However, given recent rainfall, questions remain regarding how receptive fuels will be for fire spread. As such, the status of the finest (i.e. 1-10 h fuels) will continue to be monitored for drying trends and subsequent need for fire weather highlights. ..Squitieri.. 10/08/2023 ...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 0247 PM CDT Sun Oct 08 2023 Valid 082000Z - 091200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected through tonight. ...20Z Update... Minor expansions have been made to the general thunderstorm areas across the Southwest based on visible satellite trends, but the previous reasoning remains valid. See the previous discussion below for more information. ..Dean.. 10/08/2023 .PREV DISCUSSION... /ISSUED 1059 AM CDT Sun Oct 08 2023/ ...Synopsis... A cool, dry continental air mass remains in place across much of the CONUS, and will limit the potential for thunderstorms with the exception of a few regions. Over the lower Great Lakes, warm lake water temperatures coupled with cold temperatures aloft associated with an upper low will support sufficient buoyancy for a few lightning strikes. Steep lapse rates over the Southwest combined with a modest influx of low to mid-level moisture will support isolated to scattered terrain-driven thunderstorms. Given inverted-V thermodynamic profiles in the lowest 2-3 km, a few strong wind gusts are possible. Across the southern FL Panhandle, weak forcing for ascent along a southward-migrating cold front within a weakly capped environment should support isolated thunderstorms by mid/late afternoon. 30-40 knot mid-level flow may support transient storm organization, but confidence in storm coverage and residence time over land is fairly low and precludes introducing any severe probabilities. Read more

No Mesoscale Discussions are in effect as of Sat Oct 7 23:42:02 UTC 2023.

No watches are valid as of Sat Oct 7 23:42:02 UTC 2023.