660 ACUS01 KWNS 020053 SWODY1 SPC AC 020052 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0652 PM CST Sun Dec 01 2024 Valid 020100Z - 021200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not expected through tonight. ...Synopsis... Broad mid-level troughing over the eastern CONUS continues to support widespread surface high pressure and associated cooler, stable conditions across the U.S., with no appreciable threat for thunderstorms apparent. A couple of lightning flashes remain possible over or immediately east of Lakes Ontario and Erie with lake effect snow bands. However, thunder coverage should be too sparse to warrant thunderstorm highlights this outlook. ..Squitieri.. 12/02/2024 $$  119 ACUS01 KWNS 020548 SWODY1 SPC AC 020547 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1147 PM CST Sun Dec 01 2024 Valid 021200Z - 031200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms will be possible today across deep south Texas and portions of the Great Lakes. Severe storms are not expected. ...Synopsis... A mid-level trough will persist across the eastern CONUS, with surface high pressure and colder air remaining in place over most of the U.S. Static stability will limit thunderstorm potential over most areas. A couple of lightning flashes may occur across parts of deep-south Texas, where some residual low-level moisture will remain in place. Low-topped convective snow bands are also expected over portions of the Great Lakes during the day, where a couple of lightning flashes cannot be ruled out. ..Squitieri.. 12/02/2024 $$  009 ACUS02 KWNS 020702 SWODY2 SPC AC 020701 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0101 AM CST Mon Dec 02 2024 Valid 031200Z - 041200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are possible along the Texas Coast and into portions of East Texas. No severe thunderstorms are expected. ...Synopsis... An upper-level trough will move off the east coast on Tuesday. Surface high pressure will progress east in its wake with a strong anticyclone moving from the Ozarks to the southern Appalachians through the weekend. Easterly flow across the Gulf of Mexico on the southern periphery of the anticyclone will result in some moisture making it inland across far south Texas. A few thunderstorms will be possible along the immediate coastal areas during the morning and early afternoon hours. As low-level flow becomes southerly and strengthens somewhat, moisture advection around 1 km will result in increasing elevated instability. A few elevated thunderstorms are possible in this warm-air advection regime early Wednesday morning. ..Bentley.. 12/02/2024 $$  982 ACUS03 KWNS 020828 SWODY3 SPC AC 020827 Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0227 AM CST Mon Dec 02 2024 Valid 041200Z - 051200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A few thunderstorms are possible from East Texas into the ArkLaMiss on Wednesday. No severe thunderstorms are expected. ...Synopsis... A strong mid-level jet streak will move out of the Canadian Prairies on Wednesday morning and into the central Ozarks by early Thursday morning. As this occurs, a southwesterly low-level jet will strengthen across East Texas on Wednesday and into Louisiana Wednesday night. This strengthening low-level jet and corresponding isentropic ascent in a region with weak (500-1000 J/kg MUCAPE) elevated instability may result in isolated thunderstorms across east Texas during the day Wednesday and into Louisiana, far southern Arkansas, and far western Mississippi on Wednesday night. Elsewhere, a dry, continental polar airmass will be in place with no thunderstorm potential. ..Bentley.. 12/02/2024 $$  737 ACUS48 KWNS 020856 SWOD48 SPC AC 020855 Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0255 AM CST Mon Dec 02 2024 Valid 051200Z - 101200Z ...DISCUSSION... A strong cold front will move into the Gulf on Thursday morning with a dry, continental polar airmass to spread across the eastern CONUS in its wake. This will keep thunderstorm activity limited to far south Texas late this week and into the early part of the weekend. Eventually, the moist sector will advect inland across Texas and the ArkLaTex ahead of an approaching mid-level trough late on Saturday and on Sunday. The associated cold front will likely trigger some thunderstorm activity on Sunday and Monday. However, instability appears quite limited at this time, and therefore, a substantial severe weather threat appears unlikely during the Day 4 to 8 period. ..Bentley.. 12/02/2024  883 ACUS01 KWNS 021252 SWODY1 SPC AC 021250 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0650 AM CST Mon Dec 02 2024 Valid 021300Z - 031200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected through tonight. ...Discussion... Longwave troughing will remain prevalent over the East with continued surface high pressure and mostly dry/stable conditions east of the Rockies. This scenario will considerably limit deep convective potential. A couple of lightning flashes could occur across parts of Deep South Texas, in conjunction with relatively rich low-level moisture and weak but persistent forcing for ascent. Low-topped convective snow bands, potentially including a couple of lightning flashes, are also expected over portions of the Great Lakes today. ..Guyer/Broyles.. 12/02/2024 $$  976 ACUS01 KWNS 021622 SWODY1 SPC AC 021620 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1020 AM CST Mon Dec 02 2024 Valid 021630Z - 031200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected through tonight. ...Synopsis and Discussion... A large-scale upper trough will persist over the eastern states today, while developing slowly eastward towards the western Atlantic through tonight. Rather cold mid-level temperatures will be present across the Great Lakes, which may support sporadic lightning flashes with ongoing lake effect snow bands. The best chance for isolated lightning appears to be with the band over Lake Huron. Across deep south TX, the potential for thunderstorms over land appears lower than earlier, as a stout cap noted on the observed 12Z BRO sounding will likely inhibit deep convection. While there may still be some chance for thunderstorms along/near a coastal surface front, the better lightning potential should tend to remain offshore through the end of the period. ..Gleason/Wendt.. 12/02/2024 $$  015 ACUS02 KWNS 021717 SWODY2 SPC AC 021715 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1115 AM CST Mon Dec 02 2024 Valid 031200Z - 041200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are possible along the Texas Coast. No severe thunderstorms are expected. ...Synopsis and Discussion... Upper troughing extending from the northern Mid-Atlantic states into the north-central Gulf of Mexico early Tuesday is forecast to progress eastward off the East Coast throughout the day. In its wake, a strong shortwave trough is expected to drop through the Canadian Prairies into the northern Plains/Upper Midwest late Tuesday/early Wednesday. Strong surface ridging associated with a continental polar airmass ushered in by lead troughing is also forecast to shift eastward from the Mid-South into central Appalachians throughout the day. A reinforcing surge of cold air associated with the Canadian Prairies shortwave trough will move into the northern/central Plains and Upper Midwest late Tuesday night through early Wednesday morning. This overall pattern will maintain largely stable conditions across the central and eastern CONUS while also supporting easterly flow across the Gulf of Mexico, which will result in some modest low-level moisture advection into TX Gulf Coast. Additionally, low to mid-level flow will increase across this region late Tuesday/early Wednesday in response to a deepening surface low and large-scale mass response. The resulting warm-air advection could result in a few isolated thunderstorms along the TX Coast, beginning across south TX early Tuesday before gradually shifting northward throughout the period. ..Mosier.. 12/02/2024 $$  428 ACUS03 KWNS 021927 SWODY3 SPC AC 021925 Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0125 PM CST Mon Dec 02 2024 Valid 041200Z - 051200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A few thunderstorms are possible from East Texas into the ArkLaMiss on Wednesday. No severe thunderstorms are expected. ...Synopsis and Discussion... A strong shortwave trough and accompanying intense jet streak are forecast to progress quickly southeastward from the Canadian Prairies/northern Plains through the Upper Midwest, Upper Great Lakes, and Ohio Valley on Wednesday. By early Thursday morning, the mid-latitude cyclone associated with this shortwave is forecast to be over the Lower Great Lakes, with the strong jet streak (i.e. over 120 kt at 500 mb) stretching through its base from IN through the Mid-Atlantic. Strong height falls and cold mid-level temperatures will spread eastward with this system, but the cold, dry, and stable airmass in place across the region will preclude thunderstorm development. Some moderate low-level moisture advection is anticipated from the TX Coast into the Lower MS Valley, with mid 60s dewpoints likely extending from the Middle TX Coastal Plain into far southwest LA by late Wednesday afternoon. Enhanced low/mid-level flow will persist throughout the day across this region, contributing to a large area of precipitation from the Middle TX Coast through east and much of LA and southern AR. A few deeper updrafts are possible embedded within this larger area of precipitation, with occasional lightning flashes possible throughout the afternoon and overnight. ..Mosier.. 12/02/2024 $$  942 ACUS01 KWNS 021946 SWODY1 SPC AC 021945 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0145 PM CST Mon Dec 02 2024 Valid 022000Z - 031200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected through tonight. ...20z Update... No changes are needed to the current D1 Convective Outlook. See previous discussion below for more information. ..Thornton.. 12/02/2024 .PREV DISCUSSION... /ISSUED 1020 AM CST Mon Dec 02 2024/ ...Synopsis and Discussion... A large-scale upper trough will persist over the eastern states today, while developing slowly eastward towards the western Atlantic through tonight. Rather cold mid-level temperatures will be present across the Great Lakes, which may support sporadic lightning flashes with ongoing lake effect snow bands. The best chance for isolated lightning appears to be with the band over Lake Huron. Across deep south TX, the potential for thunderstorms over land appears lower than earlier, as a stout cap noted on the observed 12Z BRO sounding will likely inhibit deep convection. While there may still be some chance for thunderstorms along/near a coastal surface front, the better lightning potential should tend to remain offshore through the end of the period. $$