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SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1142 PM CST Thu Feb 22 2024 Valid 231200Z - 241200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PARTS OF SC INTO SOUTHEAST NC... ...SUMMARY... A few strong to severe storms are possible during the afternoon and early evening over parts of South Carolina into southeast North Carolina. ...Carolinas... A mid/upper-level trough is forecast to amplify over the eastern CONUS through the day, as a strong upper-level jet (150 kt at 300 mb) intensifies near the base of the trough across the Southeast. A cold front initially draped from the central Appalachians southwestward to the FL Panhandle will move eastward through the day, as a surface low moves off of the Mid Atlantic coast and begins to deepen offshore by evening. Destabilization in advance of the cold front will generally be limited by early-day cloudiness/precipitation and modest low-level moisture. However, in the wake of morning convection, modest diurnal heating beneath cooling temperatures aloft will steepen lapse rates and allow for MLCAPE to potentially increase to around 500 J/kg. Thunderstorm development will be possible during the afternoon along/ahead of the cold front, with the greatest relative storm coverage expected from SC into southeast NC. While convection will likely remain rather low-topped, effective shear of 30-40 kt may support a few stronger cells and/or clusters, with an attendant threat of small to marginally severe hail and localized strong/damaging gusts. ..Dean/Lyons.. 02/23/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1142 PM CST Thu Feb 22 2024 Valid 231200Z - 241200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PARTS OF SC INTO SOUTHEAST NC... ...SUMMARY... A few strong to severe storms are possible during the afternoon and early evening over parts of South Carolina into southeast North Carolina. ...Carolinas... A mid/upper-level trough is forecast to amplify over the eastern CONUS through the day, as a strong upper-level jet (150 kt at 300 mb) intensifies near the base of the trough across the Southeast. A cold front initially draped from the central Appalachians southwestward to the FL Panhandle will move eastward through the day, as a surface low moves off of the Mid Atlantic coast and begins to deepen offshore by evening. Destabilization in advance of the cold front will generally be limited by early-day cloudiness/precipitation and modest low-level moisture. However, in the wake of morning convection, modest diurnal heating beneath cooling temperatures aloft will steepen lapse rates and allow for MLCAPE to potentially increase to around 500 J/kg. Thunderstorm development will be possible during the afternoon along/ahead of the cold front, with the greatest relative storm coverage expected from SC into southeast NC. While convection will likely remain rather low-topped, effective shear of 30-40 kt may support a few stronger cells and/or clusters, with an attendant threat of small to marginally severe hail and localized strong/damaging gusts. ..Dean/Lyons.. 02/23/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1142 PM CST Thu Feb 22 2024 Valid 231200Z - 241200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PARTS OF SC INTO SOUTHEAST NC... ...SUMMARY... A few strong to severe storms are possible during the afternoon and early evening over parts of South Carolina into southeast North Carolina. ...Carolinas... A mid/upper-level trough is forecast to amplify over the eastern CONUS through the day, as a strong upper-level jet (150 kt at 300 mb) intensifies near the base of the trough across the Southeast. A cold front initially draped from the central Appalachians southwestward to the FL Panhandle will move eastward through the day, as a surface low moves off of the Mid Atlantic coast and begins to deepen offshore by evening. Destabilization in advance of the cold front will generally be limited by early-day cloudiness/precipitation and modest low-level moisture. However, in the wake of morning convection, modest diurnal heating beneath cooling temperatures aloft will steepen lapse rates and allow for MLCAPE to potentially increase to around 500 J/kg. Thunderstorm development will be possible during the afternoon along/ahead of the cold front, with the greatest relative storm coverage expected from SC into southeast NC. While convection will likely remain rather low-topped, effective shear of 30-40 kt may support a few stronger cells and/or clusters, with an attendant threat of small to marginally severe hail and localized strong/damaging gusts. ..Dean/Lyons.. 02/23/2024 Read more

The Lower Colorado River Authority unanimously adopted a resolution that would permit customers to water outdoors only once per week while water storage in both Lake Travis and Lake Buchanan combined remain at less than 1.1 million acre-feet of water. The new rule, which will take effect on May 1, was needed as drought worsened, water use was high due to the increasing population in the Hill Country and lake levels were low. The combined water storage in Lake Travis and Lake Buchanan was 842,342 acre-feet on Feb. 1, which was nearly 200,000 acre-feet lower than one year ago. KVUE News Online (Austin, Texas), Feb 22, 2024

MD 0156 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PORTIONS OF CENTRAL ARKANSAS INTO NORTHWEST MISSISSIPPI AND FAR SOUTHWEST TENNESSEE
Mesoscale Discussion 0156 NWS Storm Prediction Center Norman OK 0612 PM CST Thu Feb 22 2024 Areas affected...portions of central Arkansas into northwest Mississippi and far southwest Tennessee Concerning...Severe potential...Watch unlikely Valid 230012Z - 230215Z Probability of Watch Issuance...20 percent SUMMARY...Isolated strong to severe storms may pose a risk for marginally severe hail and gusty winds this evening. A watch is not expected. DISCUSSION...As of 00z, regional radar analysis showed isolated thunderstorms over parts of central and northern AR. Over the past 30-45 min, a few of these storms have shown occasional weak supercell characteristics and deeper reflectively cores. The environment is still relatively limited with only 500-1000 J/kg of MUCAPE and 25-30 kt of effective shear. While not overly robust, the environment should remain capable of supporting marginal storm organization for a few hours this evening as storms move southeastward. Mid-level lapse rates around 7 c/km and 25-30 kt of effective shear may allow for marginally severe hail and or strong outflow winds from the strongest storms. The severe threat should gradually wane through the later evening hours as the loss of diurnal heating and nocturnal stabilization work to weaken ongoing storms. Given the limited potential for storm organization, and the isolated nature of the severe threat, a weather watch is unlikely. ..Lyons/Thompson.. 02/23/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...MEG...JAN...LZK...TSA... LAT...LON 35049424 35359424 35889333 35869222 35779123 35759110 35258993 34898958 33918983 33359061 33419208 34379390 35049424 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0649 PM CST Thu Feb 22 2024 Valid 230100Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM ARKANSAS INTO PARTS OF THE MID SOUTH... ...SUMMARY... Strong thunderstorms will continue to overspread parts of the Mid South this evening, and perhaps pose some risk for damaging wind gusts and severe hail. ...Parts of Arkansas into the Mid South... Multiple bands of thunderstorms are ongoing this evening from parts of AR into southeast MO and western KY, in association with a gradually deepening mid/upper-level trough and related cold front. MUCAPE of 500-1000 J/kg and effective shear of 25-35 kt will remain supportive of at least weakly organized convection through the evening, supporting a continued risk of isolated hail as storms move southeastward. Some modest clustering and upscale growth will be possible as storms approach western TN and northwest MS, which could pose a threat of localized strong/damaging gusts. See MCD 156 for more information. ..Dean.. 02/23/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0649 PM CST Thu Feb 22 2024 Valid 230100Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM ARKANSAS INTO PARTS OF THE MID SOUTH... ...SUMMARY... Strong thunderstorms will continue to overspread parts of the Mid South this evening, and perhaps pose some risk for damaging wind gusts and severe hail. ...Parts of Arkansas into the Mid South... Multiple bands of thunderstorms are ongoing this evening from parts of AR into southeast MO and western KY, in association with a gradually deepening mid/upper-level trough and related cold front. MUCAPE of 500-1000 J/kg and effective shear of 25-35 kt will remain supportive of at least weakly organized convection through the evening, supporting a continued risk of isolated hail as storms move southeastward. Some modest clustering and upscale growth will be possible as storms approach western TN and northwest MS, which could pose a threat of localized strong/damaging gusts. See MCD 156 for more information. ..Dean.. 02/23/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0649 PM CST Thu Feb 22 2024 Valid 230100Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM ARKANSAS INTO PARTS OF THE MID SOUTH... ...SUMMARY... Strong thunderstorms will continue to overspread parts of the Mid South this evening, and perhaps pose some risk for damaging wind gusts and severe hail. ...Parts of Arkansas into the Mid South... Multiple bands of thunderstorms are ongoing this evening from parts of AR into southeast MO and western KY, in association with a gradually deepening mid/upper-level trough and related cold front. MUCAPE of 500-1000 J/kg and effective shear of 25-35 kt will remain supportive of at least weakly organized convection through the evening, supporting a continued risk of isolated hail as storms move southeastward. Some modest clustering and upscale growth will be possible as storms approach western TN and northwest MS, which could pose a threat of localized strong/damaging gusts. See MCD 156 for more information. ..Dean.. 02/23/2024 Read more

The Missouri Senate is considering a bill that would prohibit anyone from exporting water outside of the state without a permit. Missouri Net (Jefferson City, Mo.), Feb 22, 2024

No watches are valid as of Thu Feb 22 22:46:01 UTC 2024.

No Mesoscale Discussions are in effect as of Thu Feb 22 22:46:01 UTC 2024.

MD 0155 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR SOUTHERN MISSOURI INTO NORTHERN ARKANSAS AND FAR WESTERN TENNESSEE
Mesoscale Discussion 0155 NWS Storm Prediction Center Norman OK 0141 PM CST Thu Feb 22 2024 Areas affected...southern Missouri into northern Arkansas and far western Tennessee Concerning...Severe potential...Watch unlikely Valid 221941Z - 222245Z Probability of Watch Issuance...20 percent SUMMARY...Scattered storms are forecast to gradually form near a cold front as it moves from southern Missouri into northern Arkansas. A few storms may produce marginally severe hail. DISCUSSION...Visible satellite imagery shows a mixture of cloud cover across the area, with distinct areas of heating. Recently, low-topped convection has begun to form along western portions of the area along the front, within a convergence zone. Area VWPs indicate the front is several km deep, which will aid boundary-layer lift and eventual cap breakage. As gradual low-level warming occurs from the southwest, inhibition will eventually be eroded near the front/surface trough. Although moisture is limited with less than 1.00" PWAT and dewpoints in the 50s F, cool temperatures aloft will allow for 500 to perhaps as much as 1000 J/kg MLCAPE. Low-level winds are relatively weak, but favorable deep-layer shear exists primarily above 500 mb. As such, a few storms this afternoon and into the early evening may produce marginal severe hail, with strong wind potential most likely late as storms produce aggregate outflow and propagate east/southeast toward northern MS. ..Jewell/Kerr.. 02/22/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...PAH...MEG...LZK...SGF...TSA... LAT...LON 35739376 36179356 36409259 37009063 37028986 36368942 35798966 35279068 34939214 34959328 35249362 35739376 Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0349 PM CST Thu Feb 22 2024 Valid 241200Z - 011200Z An upper-level ridge will build in across the western US with downstream troughing across the east D3/Saturday through D4/Sunday. Surface high pressure across the central US will keep winds generally light where the driest conditions are expected in the central and southern high Plains. As such, fire weather concerns will remain low through the weekend for much of the CONUS, though spotty elevated conditions in the lee of terrain features will be possible Sunday across the southern and central High Plains. Confidence is increasing in Elevated to Critical fire weather conditions returning to the High Plains on D5/Monday. Late D4/Sunday into D5/Monday an upper-level low will begin to phase with the Polar jet stream, with the western ridge drifting east and westerly flow aloft overspreading the Rockies. This pattern will favor strengthening lee troughing east of the Rockies and a return of windy/dry westerly downslope flow into the central/southern Plains. Afternoon relative humidity reductions to 10-20 percent will overlap sustained winds at 20-30 mph (gusting 40-50 mph). Recent fuel analysis indicates fuels across much of western Texas and eastern New Mexico are nearing average to above average dryness, given recent warm/dry/windy conditions from the last 2-3 days. As such, 70 percent probabilities were added across the regions of highest confidence in drying fuels that will support fire spread from eastern New Mexico south into far western Texas and north into the Texas Panhandles. Late in the period D6/Tuesday into D7/Wednesday, a deeper trough may develop across the western US before moving eastward across the Rockies, with potential for development of a strong lee cyclone and attendant cold front shifting southward. Long range guidance differences in location and speed of this developing low leading to uncertainty in how widespread lower afternoon relative humidity values will be. As such a 40 percent delineation was added, due to the strength of the forecast surface winds where medium confidence was overlap of windy/dry conditions. This threat will need to be monitored in the coming days. ..Thornton.. 02/22/2024 ...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 0349 PM CST Thu Feb 22 2024 Valid 241200Z - 011200Z An upper-level ridge will build in across the western US with downstream troughing across the east D3/Saturday through D4/Sunday. Surface high pressure across the central US will keep winds generally light where the driest conditions are expected in the central and southern high Plains. As such, fire weather concerns will remain low through the weekend for much of the CONUS, though spotty elevated conditions in the lee of terrain features will be possible Sunday across the southern and central High Plains. Confidence is increasing in Elevated to Critical fire weather conditions returning to the High Plains on D5/Monday. Late D4/Sunday into D5/Monday an upper-level low will begin to phase with the Polar jet stream, with the western ridge drifting east and westerly flow aloft overspreading the Rockies. This pattern will favor strengthening lee troughing east of the Rockies and a return of windy/dry westerly downslope flow into the central/southern Plains. Afternoon relative humidity reductions to 10-20 percent will overlap sustained winds at 20-30 mph (gusting 40-50 mph). Recent fuel analysis indicates fuels across much of western Texas and eastern New Mexico are nearing average to above average dryness, given recent warm/dry/windy conditions from the last 2-3 days. As such, 70 percent probabilities were added across the regions of highest confidence in drying fuels that will support fire spread from eastern New Mexico south into far western Texas and north into the Texas Panhandles. Late in the period D6/Tuesday into D7/Wednesday, a deeper trough may develop across the western US before moving eastward across the Rockies, with potential for development of a strong lee cyclone and attendant cold front shifting southward. Long range guidance differences in location and speed of this developing low leading to uncertainty in how widespread lower afternoon relative humidity values will be. As such a 40 percent delineation was added, due to the strength of the forecast surface winds where medium confidence was overlap of windy/dry conditions. This threat will need to be monitored in the coming days. ..Thornton.. 02/22/2024 ...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 0349 PM CST Thu Feb 22 2024 Valid 241200Z - 011200Z An upper-level ridge will build in across the western US with downstream troughing across the east D3/Saturday through D4/Sunday. Surface high pressure across the central US will keep winds generally light where the driest conditions are expected in the central and southern high Plains. As such, fire weather concerns will remain low through the weekend for much of the CONUS, though spotty elevated conditions in the lee of terrain features will be possible Sunday across the southern and central High Plains. Confidence is increasing in Elevated to Critical fire weather conditions returning to the High Plains on D5/Monday. Late D4/Sunday into D5/Monday an upper-level low will begin to phase with the Polar jet stream, with the western ridge drifting east and westerly flow aloft overspreading the Rockies. This pattern will favor strengthening lee troughing east of the Rockies and a return of windy/dry westerly downslope flow into the central/southern Plains. Afternoon relative humidity reductions to 10-20 percent will overlap sustained winds at 20-30 mph (gusting 40-50 mph). Recent fuel analysis indicates fuels across much of western Texas and eastern New Mexico are nearing average to above average dryness, given recent warm/dry/windy conditions from the last 2-3 days. As such, 70 percent probabilities were added across the regions of highest confidence in drying fuels that will support fire spread from eastern New Mexico south into far western Texas and north into the Texas Panhandles. Late in the period D6/Tuesday into D7/Wednesday, a deeper trough may develop across the western US before moving eastward across the Rockies, with potential for development of a strong lee cyclone and attendant cold front shifting southward. Long range guidance differences in location and speed of this developing low leading to uncertainty in how widespread lower afternoon relative humidity values will be. As such a 40 percent delineation was added, due to the strength of the forecast surface winds where medium confidence was overlap of windy/dry conditions. This threat will need to be monitored in the coming days. ..Thornton.. 02/22/2024 ...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 0349 PM CST Thu Feb 22 2024 Valid 241200Z - 011200Z An upper-level ridge will build in across the western US with downstream troughing across the east D3/Saturday through D4/Sunday. Surface high pressure across the central US will keep winds generally light where the driest conditions are expected in the central and southern high Plains. As such, fire weather concerns will remain low through the weekend for much of the CONUS, though spotty elevated conditions in the lee of terrain features will be possible Sunday across the southern and central High Plains. Confidence is increasing in Elevated to Critical fire weather conditions returning to the High Plains on D5/Monday. Late D4/Sunday into D5/Monday an upper-level low will begin to phase with the Polar jet stream, with the western ridge drifting east and westerly flow aloft overspreading the Rockies. This pattern will favor strengthening lee troughing east of the Rockies and a return of windy/dry westerly downslope flow into the central/southern Plains. Afternoon relative humidity reductions to 10-20 percent will overlap sustained winds at 20-30 mph (gusting 40-50 mph). Recent fuel analysis indicates fuels across much of western Texas and eastern New Mexico are nearing average to above average dryness, given recent warm/dry/windy conditions from the last 2-3 days. As such, 70 percent probabilities were added across the regions of highest confidence in drying fuels that will support fire spread from eastern New Mexico south into far western Texas and north into the Texas Panhandles. Late in the period D6/Tuesday into D7/Wednesday, a deeper trough may develop across the western US before moving eastward across the Rockies, with potential for development of a strong lee cyclone and attendant cold front shifting southward. Long range guidance differences in location and speed of this developing low leading to uncertainty in how widespread lower afternoon relative humidity values will be. As such a 40 percent delineation was added, due to the strength of the forecast surface winds where medium confidence was overlap of windy/dry conditions. This threat will need to be monitored in the coming days. ..Thornton.. 02/22/2024 ...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 0349 PM CST Thu Feb 22 2024 Valid 241200Z - 011200Z An upper-level ridge will build in across the western US with downstream troughing across the east D3/Saturday through D4/Sunday. Surface high pressure across the central US will keep winds generally light where the driest conditions are expected in the central and southern high Plains. As such, fire weather concerns will remain low through the weekend for much of the CONUS, though spotty elevated conditions in the lee of terrain features will be possible Sunday across the southern and central High Plains. Confidence is increasing in Elevated to Critical fire weather conditions returning to the High Plains on D5/Monday. Late D4/Sunday into D5/Monday an upper-level low will begin to phase with the Polar jet stream, with the western ridge drifting east and westerly flow aloft overspreading the Rockies. This pattern will favor strengthening lee troughing east of the Rockies and a return of windy/dry westerly downslope flow into the central/southern Plains. Afternoon relative humidity reductions to 10-20 percent will overlap sustained winds at 20-30 mph (gusting 40-50 mph). Recent fuel analysis indicates fuels across much of western Texas and eastern New Mexico are nearing average to above average dryness, given recent warm/dry/windy conditions from the last 2-3 days. As such, 70 percent probabilities were added across the regions of highest confidence in drying fuels that will support fire spread from eastern New Mexico south into far western Texas and north into the Texas Panhandles. Late in the period D6/Tuesday into D7/Wednesday, a deeper trough may develop across the western US before moving eastward across the Rockies, with potential for development of a strong lee cyclone and attendant cold front shifting southward. Long range guidance differences in location and speed of this developing low leading to uncertainty in how widespread lower afternoon relative humidity values will be. As such a 40 percent delineation was added, due to the strength of the forecast surface winds where medium confidence was overlap of windy/dry conditions. This threat will need to be monitored in the coming days. ..Thornton.. 02/22/2024 ...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 0349 PM CST Thu Feb 22 2024 Valid 241200Z - 011200Z An upper-level ridge will build in across the western US with downstream troughing across the east D3/Saturday through D4/Sunday. Surface high pressure across the central US will keep winds generally light where the driest conditions are expected in the central and southern high Plains. As such, fire weather concerns will remain low through the weekend for much of the CONUS, though spotty elevated conditions in the lee of terrain features will be possible Sunday across the southern and central High Plains. Confidence is increasing in Elevated to Critical fire weather conditions returning to the High Plains on D5/Monday. Late D4/Sunday into D5/Monday an upper-level low will begin to phase with the Polar jet stream, with the western ridge drifting east and westerly flow aloft overspreading the Rockies. This pattern will favor strengthening lee troughing east of the Rockies and a return of windy/dry westerly downslope flow into the central/southern Plains. Afternoon relative humidity reductions to 10-20 percent will overlap sustained winds at 20-30 mph (gusting 40-50 mph). Recent fuel analysis indicates fuels across much of western Texas and eastern New Mexico are nearing average to above average dryness, given recent warm/dry/windy conditions from the last 2-3 days. As such, 70 percent probabilities were added across the regions of highest confidence in drying fuels that will support fire spread from eastern New Mexico south into far western Texas and north into the Texas Panhandles. Late in the period D6/Tuesday into D7/Wednesday, a deeper trough may develop across the western US before moving eastward across the Rockies, with potential for development of a strong lee cyclone and attendant cold front shifting southward. Long range guidance differences in location and speed of this developing low leading to uncertainty in how widespread lower afternoon relative humidity values will be. As such a 40 percent delineation was added, due to the strength of the forecast surface winds where medium confidence was overlap of windy/dry conditions. This threat will need to be monitored in the coming days. ..Thornton.. 02/22/2024 ...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 0152 PM CST Thu Feb 22 2024 Valid 222000Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE MID-SOUTH... ...SUMMARY... Strong thunderstorms may develop and overspread parts of the Mid South late this afternoon/evening, and perhaps pose some risk for damaging wind gusts and severe hail. ...20Z Update... Heating along the surface boundary in southern Missouri has promoted some weak convective development. Confidence in the potential for marginally severe hail has increased within this corridor for expansion of 5% hail probabilities. See MCD #155 for greater mesoscale details in regards to this threat. Much of western Tennessee remains cloudy. Confidence in sufficient destabilization for an appreciable severe threat is low. ..Wendt.. 02/22/2024 .PREV DISCUSSION... /ISSUED 1020 AM CST Thu Feb 22 2024/ ...Synopsis... A couple of short wave perturbations of Arctic origins (currently west of Hudson Bay) are forecast to continue to consolidate into a vigorous digging short wave trough to the southwest through south of Hudson Bay into the James Bay vicinity today through tonight. It still appears that this will contribute to larger-scale mid/upper trough amplification across the northern into mid-latitudes of eastern North America (and accompanied by a significant cold front crossing the Canadian/U.S. border into the northern Great Plains through upper Great Lakes region by late tonight). In phase with this regime, models indicate that the stronger westerlies across the southern mid- and subtropical latitudes will trend broadly cyclonic across the southern Great Plains through the Southeast, with one or two consolidating embedded lower amplitude perturbations digging from the central Great Plains/Ozark Plateau and lower Ohio Valley through the lower Mississippi/Tennessee Valleys and southern Appalachians by 12Z Friday. While there may be some further deepening of surface troughing shifting from the southern Great Plains through lower Ohio Valley into the Southeast through Mid Atlantic, models indicate that any embedded cyclogenesis will remain negligible, at least until it shifts offshore Friday through Friday night. In the wake of initially more amplified mid-level troughing now beginning to accelerate away from the Atlantic Seaboard, boundary-layer modification over the Gulf of Mexico has been slow. A limited moisture return is ongoing on moderately strong southerly return flow preceding the surface trough, but substantive further improvement still appears unlikely through this period. ...Mid South and Ohio/Tennessee Valleys... Observed and forecast soundings suggest that moistening supportive of thunderstorm development, with large-scale ascent, is generally occurring above a stable boundary, and beneath warm/dry capping layers aloft, with profiles supportive of only weak CAPE. It appears that this will remain the case as forcing for ascent begins to support increasing thunderstorm activity ahead of the digging mid-level troughing, southeast of the lower Ohio Valley through the Tennessee Valley and portions of the lower Mississippi Valley later today through tonight. However, at least some model output, perhaps most notably the High Resolution Rapid Refresh, suggests that a somewhat better moist (and potentially unstable) inflow to the southwestern flank of this forcing could enhance thunderstorm development this evening across parts of the Mid South into Gulf States. The HRRR depiction of convection includes an organizing cluster with 45+ kt rear inflow developing near or above the 850-800 mb layer. Even if this verifies, the potential efficiency of downward momentum transport to the surface remains unclear based on forecast soundings, but a few locally strong/damaging wind gusts might not be out of the question. Read more