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NorthGeorgiaWX

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  1. SPC 2000Z Day 1 Outlook Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Tue Mar 26 2024 Valid 262000Z - 271200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF LOWER MICHIGAN...EASTERN INDIANA...AND WESTERN OHIO... ...SUMMARY... Damaging wind gusts remain possible late this afternoon into the evening over parts of the Lower Michigan/southern Great Lakes region, and the eastern Gulf Coastal Plain. ...20Z Update... Severe probabilities have been trimmed across parts of IN and southwest lower MI, in the wake of a cold frontal passage. Otherwise, no changes have been made. See the previous discussion below and MCD 307 for more details. A small part of the Marginal Risk has been trimmed across the FL Panhandle, based on the progression of ongoing convection. See the previous discussion below for more details regarding the threat across the FL Peninsula and south GA. ..Dean.. 03/26/2024 .PREV DISCUSSION... /ISSUED 1101 AM CDT Tue Mar 26 2024/ ...FL Panhandle and Vicinity... A surface cold front continues to sag southward across parts of AL and the FL Panhandle. Scattered thunderstorms are occurring along the front (mainly offshore), with occasional updrafts showing some organization. It is expected that the bulk of this activity will remain offshore due to widespread clouds and limited destabilization inland. However, there is some chance of a strong storm or two this afternoon. After dark, most model guidance suggest the frontal convection will strengthen, with a continued risk of a few strong storms into north FL. ...Lower MI/IN/Western OH... A strong cold front is sweeping eastward into western IN late this morning, and will move across Lower MI/IN/western OH through the day. Widespread clouds and meager low-level moisture ahead of the front will limit destabilization, with forecast soundings suggesting the convective layer may remain too shallow to support much lightning. Nevertheless, strong winds just above the surface coupled with cold temperatures aloft may be sufficient for a few strong storms later today, capable of damaging wind gusts. The time period of greatest concern should roughly be from 22-02z. Read more View the full article
  2. SPC 2000Z Day 1 Outlook Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Tue Mar 26 2024 Valid 262000Z - 271200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF LOWER MICHIGAN...EASTERN INDIANA...AND WESTERN OHIO... ...SUMMARY... Damaging wind gusts remain possible late this afternoon into the evening over parts of the Lower Michigan/southern Great Lakes region, and the eastern Gulf Coastal Plain. ...20Z Update... Severe probabilities have been trimmed across parts of IN and southwest lower MI, in the wake of a cold frontal passage. Otherwise, no changes have been made. See the previous discussion below and MCD 307 for more details. A small part of the Marginal Risk has been trimmed across the FL Panhandle, based on the progression of ongoing convection. See the previous discussion below for more details regarding the threat across the FL Peninsula and south GA. ..Dean.. 03/26/2024 .PREV DISCUSSION... /ISSUED 1101 AM CDT Tue Mar 26 2024/ ...FL Panhandle and Vicinity... A surface cold front continues to sag southward across parts of AL and the FL Panhandle. Scattered thunderstorms are occurring along the front (mainly offshore), with occasional updrafts showing some organization. It is expected that the bulk of this activity will remain offshore due to widespread clouds and limited destabilization inland. However, there is some chance of a strong storm or two this afternoon. After dark, most model guidance suggest the frontal convection will strengthen, with a continued risk of a few strong storms into north FL. ...Lower MI/IN/Western OH... A strong cold front is sweeping eastward into western IN late this morning, and will move across Lower MI/IN/western OH through the day. Widespread clouds and meager low-level moisture ahead of the front will limit destabilization, with forecast soundings suggesting the convective layer may remain too shallow to support much lightning. Nevertheless, strong winds just above the surface coupled with cold temperatures aloft may be sufficient for a few strong storms later today, capable of damaging wind gusts. The time period of greatest concern should roughly be from 22-02z. Read more View the full article
  3. SPC Day 2 Fire Weather Outlook Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0243 PM CDT Tue Mar 26 2024 Valid 271200Z - 281200Z ...20z Update... Newest forecast guidance has shown the cold front moving slightly farther south than expected over parts of west TX. As such, the elevated area has been shifted south toward more concentrated dry and breezy conditions. Elevated fire-weather concerns remain possible over West TX and the Trans Pecos. See the previous discussion for more information. ..Lyons.. 03/26/2024 .PREV DISCUSSION... /ISSUED 0203 AM CDT Tue Mar 26 2024/ ...Synopsis... The western periphery of a mid-level trough will overspread the southern High Plains tomorrow/Wednesday, encouraging weak surface low development and deep-layer northwesterly flow over portions of southeastern New Mexico into western Texas. Dry downslope winds should occur west of the surface low, promoting some wildfire-spread potential given modestly receptive fuels. By afternoon peak heating, northwesterly sustained surface winds of 15-25 mph will coincide with 10-15 percent RH for at least a few hours Wednesday afternoon. Since fuel ERCs are only around the 50th percentile, Elevated highlights have been introduced. ...Please see www.spc.noaa.gov/fire for graphic product... Read more View the full article
  4. SPC Day 2 Fire Weather Outlook Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0243 PM CDT Tue Mar 26 2024 Valid 271200Z - 281200Z ...20z Update... Newest forecast guidance has shown the cold front moving slightly farther south than expected over parts of west TX. As such, the elevated area has been shifted south toward more concentrated dry and breezy conditions. Elevated fire-weather concerns remain possible over West TX and the Trans Pecos. See the previous discussion for more information. ..Lyons.. 03/26/2024 .PREV DISCUSSION... /ISSUED 0203 AM CDT Tue Mar 26 2024/ ...Synopsis... The western periphery of a mid-level trough will overspread the southern High Plains tomorrow/Wednesday, encouraging weak surface low development and deep-layer northwesterly flow over portions of southeastern New Mexico into western Texas. Dry downslope winds should occur west of the surface low, promoting some wildfire-spread potential given modestly receptive fuels. By afternoon peak heating, northwesterly sustained surface winds of 15-25 mph will coincide with 10-15 percent RH for at least a few hours Wednesday afternoon. Since fuel ERCs are only around the 50th percentile, Elevated highlights have been introduced. ...Please see www.spc.noaa.gov/fire for graphic product... Read more View the full article
  5. MD 0307 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR MUCH OF LOWER MICHIGAN...NORTHEASTERN INDIANA...NORTHWESTERN OHIO Mesoscale Discussion 0307 NWS Storm Prediction Center Norman OK 0108 PM CDT Tue Mar 26 2024 Areas affected...much of lower Michigan...northeastern Indiana...northwestern Ohio Concerning...Severe potential...Watch unlikely Valid 261808Z - 262045Z Probability of Watch Issuance...20 percent SUMMARY...An increasingly organized band of showers, and developing thunderstorms, may be accompanied by increasing potential for strong to locally severe surface gusts by 4-5 PM EDT. It is still not clear that a severe weather watch is needed, but trends are being monitored for this possibility. DISCUSSION...Weak destabilization within a narrow pre-frontal corridor of low-level warming and moistening, coupled with large-scale ascent aided by warm advection, has contributed to increasing showers across western lower Michigan southward toward the Indianapolis IN vicinity. Some lightning has recently been noted southeast of South Bend, but low-level lapse rates are still relatively modest and the moistening is only contributing to very weak CAPE. This may be slow to improve, but breaks in cloud cover may allow for at least some continuing insolation during the next few hours. Perhaps more notably, within the left exit region of an intensifying mid-level jet (in excess of 100 kt around 500 mb) nosing north-northeastward through the lower Ohio Valley, strengthening low-level frontogenetic forcing is forecast along the eastward advancing front across central lower Michigan through the Indiana/Ohio border area by 20-21Z. This may support a consolidating and deepening band of convection with increasing potential to produce lightning. In the presence of fairly strong (and strongly sheared) south-southwesterly lower/mid-tropospheric flow (including 40-50+ kt mean ambient flow in the lowest 3-6 km AGL), activity may become increasingly organized. Downward mixing of momentum may contribute to potentially damaging wind gusts reaching the surface in northeastward surging segments, while the line advances eastward toward the lower Great Lakes region through late afternoon. ..Kerr/Hart.. 03/26/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...CLE...ILN...DTX...APX...IWX...GRR... LAT...LON 40428544 42978529 44938539 44928356 43948281 41398341 40408392 40428544 Read more View the full article
  6. SPC 1730Z Day 2 Outlook Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1229 PM CDT Tue Mar 26 2024 Valid 271200Z - 281200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS NORTH FLORIDA AND ALSO ACROSS PARTS OF NORTH-CENTRAL TEXAS... ...SUMMARY... Isolated strong to severe thunderstorms may occur Wednesday across north Florida, and also across parts of north-central Texas. Isolated hail and damaging winds should be the main hazards for both areas. ...Florida into the Carolinas... A cold front is forecast to gradually move eastward across parts of Florida into the Carolinas on Wednesday, in conjunction with the southern portion of a deep upper-level trough moving into the eastern CONUS. Early-day convection and related cloudiness may tend to limit destabilization, but some diurnal heating along the eastern periphery of the morning convection may support MLCAPE increasing above 1000 J/kg by early afternoon. Favorable deep-layer shear will support potential for a few strong storms through the forecast period, with potential for isolated hail and damaging gusts. Multiple rounds of storms will be possible in some areas, with some convection lingering through the morning, and later redevelopment possible in areas where stronger heating occurs, and also potentially along the trailing cold front. Farther north, a strong storm or two cannot be ruled out from southeast GA into the coastal Carolinas vicinity, along/ahead of the cold front. However, there is greater uncertainty regarding potential for destabilization across these areas in the wake of morning convection. If some diurnal heating/destabilization can occur in advance of the front, then an isolated severe threat could eventually evolve, though uncertainty remains too high to include severe probabilities at this time. ...Parts of north into central TX... Despite generally meager low-level moisture across the region, cold temperatures aloft (500 mb temperatures around -25C) will support modest diurnal destabilization from north into central TX. Isolated to widely scattered thunderstorm development is expected by late afternoon. Deep-layer shear will be sufficient for some storm organization, and a southeastward-moving supercell or two will be possible. Hail may be the most likely hazard, given the cold temperature profiles, but steep lapse rates could also support isolated strong/damaging gusts. ..Dean.. 03/26/2024 Read more View the full article
  7. SPC 1730Z Day 2 Outlook Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1229 PM CDT Tue Mar 26 2024 Valid 271200Z - 281200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS NORTH FLORIDA AND ALSO ACROSS PARTS OF NORTH-CENTRAL TEXAS... ...SUMMARY... Isolated strong to severe thunderstorms may occur Wednesday across north Florida, and also across parts of north-central Texas. Isolated hail and damaging winds should be the main hazards for both areas. ...Florida into the Carolinas... A cold front is forecast to gradually move eastward across parts of Florida into the Carolinas on Wednesday, in conjunction with the southern portion of a deep upper-level trough moving into the eastern CONUS. Early-day convection and related cloudiness may tend to limit destabilization, but some diurnal heating along the eastern periphery of the morning convection may support MLCAPE increasing above 1000 J/kg by early afternoon. Favorable deep-layer shear will support potential for a few strong storms through the forecast period, with potential for isolated hail and damaging gusts. Multiple rounds of storms will be possible in some areas, with some convection lingering through the morning, and later redevelopment possible in areas where stronger heating occurs, and also potentially along the trailing cold front. Farther north, a strong storm or two cannot be ruled out from southeast GA into the coastal Carolinas vicinity, along/ahead of the cold front. However, there is greater uncertainty regarding potential for destabilization across these areas in the wake of morning convection. If some diurnal heating/destabilization can occur in advance of the front, then an isolated severe threat could eventually evolve, though uncertainty remains too high to include severe probabilities at this time. ...Parts of north into central TX... Despite generally meager low-level moisture across the region, cold temperatures aloft (500 mb temperatures around -25C) will support modest diurnal destabilization from north into central TX. Isolated to widely scattered thunderstorm development is expected by late afternoon. Deep-layer shear will be sufficient for some storm organization, and a southeastward-moving supercell or two will be possible. Hail may be the most likely hazard, given the cold temperature profiles, but steep lapse rates could also support isolated strong/damaging gusts. ..Dean.. 03/26/2024 Read more View the full article
  8. MD 0306 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR CENTRAL FLORIDA PANHANDLE Mesoscale Discussion 0306 NWS Storm Prediction Center Norman OK 1204 PM CDT Tue Mar 26 2024 Areas affected...central Florida Panhandle Concerning...Severe potential...Watch unlikely Valid 261704Z - 261900Z Probability of Watch Issuance...5 percent SUMMARY...Marginal risk of wind and a tornado through the afternoon. DISCUSSION...A broken line of convection is ongoing this afternoon across southern Alabama into the central Florida Panhandle. This activity remains elevated, with surface inhibition evident from modified 12z observed soundings from Tallahassee and in forecast RAP soundings along the Gulf. In addition, extensive mid-level cloud cover remains in place across much of the Panhandle this afternoon, limiting destabilization. As a result, the most favorable warm sector remains offshore, with minimal MLCAPE observed inland. Over the next couple of hours as this convection moves eastward, a few instances of more robust embedded storms may be possible where the warm sector can creep inland. Wind profiles indicate deep layer shear around 55-60 kts. Given that convection is likely rooted above the surface, much of the low-level cyclonic curvature of hodographs will not be realized. Should the warm sector move inland and a storm could become surface based, an isolated tornado could be possible, though weak low-level lapse rates and strong surface inhibition will likely work to further inhibit this potential. Otherwise, the main threats will remain occasional gusty winds. A watch is unlikely to be needed at this time. ..Thornton/Hart.. 03/26/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...TAE...MOB... LAT...LON 30458635 30858593 30958555 30918513 30548400 30268382 30138382 29808431 29598493 29688548 29748581 30048640 30178664 30458635 Read more View the full article
  9. SPC Day 1 Fire Weather Outlook Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1147 AM CDT Tue Mar 26 2024 Valid 261700Z - 271200Z ...NO CRITICAL AREAS... ...17z Update... No changes, see the previous discussion for more information. ..Lyons.. 03/26/2024 .PREV DISCUSSION... /ISSUED 0129 AM CDT Tue Mar 26 2024/ ...Synopsis... Surface high pressure and associated cooler air will overspread the Plains states as a mid-level trough and accompanying surface low progress toward the eastern U.S. and Canada today. Generally quiescent fire weather conditions are expected for most of the U.S. One small exception may be portions of western Texas during the afternoon hours, where locally dry and breezy conditions may occur. Nonetheless, wildfire-spread potential should remain localized, since RH may not dip below 20 percent on a widespread basis. ...Please see www.spc.noaa.gov/fire for graphic product... Read more View the full article
  10. SPC Day 1 Fire Weather Outlook Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1147 AM CDT Tue Mar 26 2024 Valid 261700Z - 271200Z ...NO CRITICAL AREAS... ...17z Update... No changes, see the previous discussion for more information. ..Lyons.. 03/26/2024 .PREV DISCUSSION... /ISSUED 0129 AM CDT Tue Mar 26 2024/ ...Synopsis... Surface high pressure and associated cooler air will overspread the Plains states as a mid-level trough and accompanying surface low progress toward the eastern U.S. and Canada today. Generally quiescent fire weather conditions are expected for most of the U.S. One small exception may be portions of western Texas during the afternoon hours, where locally dry and breezy conditions may occur. Nonetheless, wildfire-spread potential should remain localized, since RH may not dip below 20 percent on a widespread basis. ...Please see www.spc.noaa.gov/fire for graphic product... Read more View the full article
  11. SPC 1630Z Day 1 Outlook Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1101 AM CDT Tue Mar 26 2024 Valid 261630Z - 271200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON OVER PORTIONS OF LOWER MICHIGAN...EASTERN INDIANA...AND WESTERN OHIO.... ...SUMMARY... Damaging wind gusts are possible today over parts of the Lower Michigan/southern Great Lakes region, and the eastern Gulf Coastal Plain. ...FL Panhandle and Vicinity... A surface cold front continues to sag southward across parts of AL and the FL Panhandle. Scattered thunderstorms are occurring along the front (mainly offshore), with occasional updrafts showing some organization. It is expected that the bulk of this activity will remain offshore due to widespread clouds and limited destabilization inland. However, there is some chance of a strong storm or two this afternoon. After dark, most model guidance suggest the frontal convection will strengthen, with a continued risk of a few strong storms into north FL. ...Lower MI/IN/Western OH... A strong cold front is sweeping eastward into western IN late this morning, and will move across Lower MI/IN/western OH through the day. Widespread clouds and meager low-level moisture ahead of the front will limit destabilization, with forecast soundings suggesting the convective layer may remain too shallow to support much lightning. Nevertheless, strong winds just above the surface coupled with cold temperatures aloft may be sufficient for a few strong storms later today, capable of damaging wind gusts. The time period of greatest concern should roughly be from 22-02z. ..Hart/Thornton.. 03/26/2024 Read more View the full article
  12. SPC 1630Z Day 1 Outlook Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1101 AM CDT Tue Mar 26 2024 Valid 261630Z - 271200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON OVER PORTIONS OF LOWER MICHIGAN...EASTERN INDIANA...AND WESTERN OHIO.... ...SUMMARY... Damaging wind gusts are possible today over parts of the Lower Michigan/southern Great Lakes region, and the eastern Gulf Coastal Plain. ...FL Panhandle and Vicinity... A surface cold front continues to sag southward across parts of AL and the FL Panhandle. Scattered thunderstorms are occurring along the front (mainly offshore), with occasional updrafts showing some organization. It is expected that the bulk of this activity will remain offshore due to widespread clouds and limited destabilization inland. However, there is some chance of a strong storm or two this afternoon. After dark, most model guidance suggest the frontal convection will strengthen, with a continued risk of a few strong storms into north FL. ...Lower MI/IN/Western OH... A strong cold front is sweeping eastward into western IN late this morning, and will move across Lower MI/IN/western OH through the day. Widespread clouds and meager low-level moisture ahead of the front will limit destabilization, with forecast soundings suggesting the convective layer may remain too shallow to support much lightning. Nevertheless, strong winds just above the surface coupled with cold temperatures aloft may be sufficient for a few strong storms later today, capable of damaging wind gusts. The time period of greatest concern should roughly be from 22-02z. ..Hart/Thornton.. 03/26/2024 Read more View the full article
  13. Flood Warning issued March 26 at 11:23AM EDT by NWS Charleston SCView the full article
  14. Flood Warning issued March 26 at 11:23AM EDT by NWS Charleston SCView the full article
  15. Flood Warning issued March 26 at 11:23AM EDT until March 28 at 8:00PM EDT by NWS Charleston SCView the full article
  16. Flood Warning issued March 26 at 10:28AM EDT by NWS Jacksonville FLView the full article
  17. Flood Warning issued March 26 at 10:28AM EDT by NWS Jacksonville FLView the full article
  18. SPC 1300Z Day 1 Outlook Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0749 AM CDT Tue Mar 26 2024 Valid 261300Z - 271200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE MICHIANA REGION TO EASTERN INDIANA...WESTERN OHIO AND CENTRAL LOWER MICHIGAN... ...SUMMARY... Damaging to severe thunderstorm gusts are possible today over parts of the Lower Michigan/southern Great Lakes region, and the eastern Gulf Coastal Plain. ...Synopsis... In mid/upper levels, mean troughing will shift eastward into the central CONUS, as northern- and southern-stream perturbations move into phase. The northern-stream system -- now manifest as a complex, closed cyclone over central Canada -- should remain nearly in place, but with intensification of its southern part into a distinct, closed 500-mb low over the southern MB/SK line by 18Z today. The low then should dig southeastward and eastward over the northern international border region, reaching northern MN and adjoining northwestern ON by 12Z tomorrow. To its southeast, a mid/upper-level cyclone over IA is devolving into an open-wave trough, and will pivot across the upper Mississippi Valley today. By 00Z, that trough should extend from western Lake Superior across WI to northwestern IN. By 12Z, a weakened version will have ejected to northern ON. In the southern stream, a series of mostly low-amplitude shortwave troughs and vorticity maxima will pivot from the Desert Southwest across TX to the lower Mississippi and Tennessee Valley regions, shifting that part of the larger-scale trough to Coahuila and west-central TX by the end of the period. The 11Z surface analysis showed a strong/sub-989-mb low over west- central WI, with polar cold front across western IL, to near MEM, then southwestward over southwestern LA and the northwestern Gulf. The low should occlude and move northeastward to near MQT by 00Z, with polar front overtaking a leading/Pacific boundary across eastern Lower MI and western OH, then extending across middle TN to southeastern LA. The outflow-reinforced, Pacific front will shift from its present position over parts of southern AL and northwestern Fl Panhandle eastward across the Southeast, reaching western SC, central GA and the AAF area by 00Z. The combined front should reach central SC, southeastern GA and the FL coastal bend by 12Z. ...Southern Great Lakes, Lower MI... Surface-based convection is expected to develop this afternoon over western parts of the outlook area, in a zone of favorable low-level convergence near the arctic front, into a corridor of diurnal heating behind a plume of morning clouds/precip. Though buoyancy will be modest (MLCAPE generally under 500 J/kg), and much of the convection may not even deepen enough to produce lightning, fast cell motions and downward momentum transport from intense flow aloft may result in sporadic damaging to severe downdrafts. Even with activity being low-topped, 50-60 kt cloud-layer shear vectors aligned nearly parallel to the front will support an organized, quasi-linear convective system (QLCS). Convection should race northeastward across parts of IN, Lower MI and western OH while backbuilding somewhat, spreading a threat for strong/locally severe gusts over the region for a few hours. Activity should weaken this evening as it encounters both weaker ambient theta-e and nocturnal diabatic stabilization. ...Eastern Gulf Coastal Plain... A swath of precip, with scattered embedded thunderstorms, will continue to shift eastward across southern parts of AL/GA and the FL Panhandle through the period. Most of this activity should remain behind the outflow-reinforced front, keeping severe potential marginal. Though the overall threat appears to have decreased for this morning, isolated strong-severe gusts or a brief tornado still are possible with the convection as it shifts eastward across the outlook area through today and tonight. The net vector motion of the boundary remains to the right of flow aloft. Accordingly, anafrontal convective behavior has persisted for several hours as cells form either on the boundary or just to its east, then move to the cold side before deepening substantially. Isolated/brief strengthening of any such cells to severe limits remains possible, but conditional. Farther east, forecast soundings reasonably suggest that elevated buoyancy developing this afternoon and evening will transition to effectively surface-based late overnight (after about 08Z), and spread inland across the eastern Panhandle, coastal bend and southern GA region ahead of the boundary. A wind shift near the surface, from southeasterly off the relatively stable FL Peninsula to southerly and south-southwesterly off the Gulf, appears responsible for that, and may increase boundary-layer moisture/theta-e enough to yield 500-1000 J/kg MLCAPE. Some reintensification of the convection therefore is possible for a few hours before the start of the day-2 period. ...Central AZ... Isolated to widely scattered thunderstorms are expected today, particularly along and north of the Mogollon Rim. A few cells may produce strong gusts or small hail. The last in a series of shortwaves -- apparent in moisture-channel imagery over the Sierra and western NV -- should shift southeastward across this region today, contributing to cold air aloft (-25 deg C or less at 500 mb) and steep midlevel lapse rates. Meanwhile, diurnal heating of higher elevations on/above the rim will destabilize the boundary later and remove CINH, contributing to a field of up to about 500 J/kg MLCAPE. While low/middle-level flow will be nearly unidirectional and not very strong (generally less than 25 kt from surface to 500 mb), with effective-shear magnitudes only around 20-30 kt, intense upper/anvil-level flow may aid with some storm organization. Severe potential appears too low and conditional for an outlook area at this time. ..Edwards/Leitman.. 03/26/2024 Read more View the full article
  19. SPC 1300Z Day 1 Outlook Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0749 AM CDT Tue Mar 26 2024 Valid 261300Z - 271200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE MICHIANA REGION TO EASTERN INDIANA...WESTERN OHIO AND CENTRAL LOWER MICHIGAN... ...SUMMARY... Damaging to severe thunderstorm gusts are possible today over parts of the Lower Michigan/southern Great Lakes region, and the eastern Gulf Coastal Plain. ...Synopsis... In mid/upper levels, mean troughing will shift eastward into the central CONUS, as northern- and southern-stream perturbations move into phase. The northern-stream system -- now manifest as a complex, closed cyclone over central Canada -- should remain nearly in place, but with intensification of its southern part into a distinct, closed 500-mb low over the southern MB/SK line by 18Z today. The low then should dig southeastward and eastward over the northern international border region, reaching northern MN and adjoining northwestern ON by 12Z tomorrow. To its southeast, a mid/upper-level cyclone over IA is devolving into an open-wave trough, and will pivot across the upper Mississippi Valley today. By 00Z, that trough should extend from western Lake Superior across WI to northwestern IN. By 12Z, a weakened version will have ejected to northern ON. In the southern stream, a series of mostly low-amplitude shortwave troughs and vorticity maxima will pivot from the Desert Southwest across TX to the lower Mississippi and Tennessee Valley regions, shifting that part of the larger-scale trough to Coahuila and west-central TX by the end of the period. The 11Z surface analysis showed a strong/sub-989-mb low over west- central WI, with polar cold front across western IL, to near MEM, then southwestward over southwestern LA and the northwestern Gulf. The low should occlude and move northeastward to near MQT by 00Z, with polar front overtaking a leading/Pacific boundary across eastern Lower MI and western OH, then extending across middle TN to southeastern LA. The outflow-reinforced, Pacific front will shift from its present position over parts of southern AL and northwestern Fl Panhandle eastward across the Southeast, reaching western SC, central GA and the AAF area by 00Z. The combined front should reach central SC, southeastern GA and the FL coastal bend by 12Z. ...Southern Great Lakes, Lower MI... Surface-based convection is expected to develop this afternoon over western parts of the outlook area, in a zone of favorable low-level convergence near the arctic front, into a corridor of diurnal heating behind a plume of morning clouds/precip. Though buoyancy will be modest (MLCAPE generally under 500 J/kg), and much of the convection may not even deepen enough to produce lightning, fast cell motions and downward momentum transport from intense flow aloft may result in sporadic damaging to severe downdrafts. Even with activity being low-topped, 50-60 kt cloud-layer shear vectors aligned nearly parallel to the front will support an organized, quasi-linear convective system (QLCS). Convection should race northeastward across parts of IN, Lower MI and western OH while backbuilding somewhat, spreading a threat for strong/locally severe gusts over the region for a few hours. Activity should weaken this evening as it encounters both weaker ambient theta-e and nocturnal diabatic stabilization. ...Eastern Gulf Coastal Plain... A swath of precip, with scattered embedded thunderstorms, will continue to shift eastward across southern parts of AL/GA and the FL Panhandle through the period. Most of this activity should remain behind the outflow-reinforced front, keeping severe potential marginal. Though the overall threat appears to have decreased for this morning, isolated strong-severe gusts or a brief tornado still are possible with the convection as it shifts eastward across the outlook area through today and tonight. The net vector motion of the boundary remains to the right of flow aloft. Accordingly, anafrontal convective behavior has persisted for several hours as cells form either on the boundary or just to its east, then move to the cold side before deepening substantially. Isolated/brief strengthening of any such cells to severe limits remains possible, but conditional. Farther east, forecast soundings reasonably suggest that elevated buoyancy developing this afternoon and evening will transition to effectively surface-based late overnight (after about 08Z), and spread inland across the eastern Panhandle, coastal bend and southern GA region ahead of the boundary. A wind shift near the surface, from southeasterly off the relatively stable FL Peninsula to southerly and south-southwesterly off the Gulf, appears responsible for that, and may increase boundary-layer moisture/theta-e enough to yield 500-1000 J/kg MLCAPE. Some reintensification of the convection therefore is possible for a few hours before the start of the day-2 period. ...Central AZ... Isolated to widely scattered thunderstorms are expected today, particularly along and north of the Mogollon Rim. A few cells may produce strong gusts or small hail. The last in a series of shortwaves -- apparent in moisture-channel imagery over the Sierra and western NV -- should shift southeastward across this region today, contributing to cold air aloft (-25 deg C or less at 500 mb) and steep midlevel lapse rates. Meanwhile, diurnal heating of higher elevations on/above the rim will destabilize the boundary later and remove CINH, contributing to a field of up to about 500 J/kg MLCAPE. While low/middle-level flow will be nearly unidirectional and not very strong (generally less than 25 kt from surface to 500 mb), with effective-shear magnitudes only around 20-30 kt, intense upper/anvil-level flow may aid with some storm organization. Severe potential appears too low and conditional for an outlook area at this time. ..Edwards/Leitman.. 03/26/2024 Read more View the full article
  20. SPC 1300Z Day 1 Outlook Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0749 AM CDT Tue Mar 26 2024 Valid 261300Z - 271200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE MICHIANA REGION TO EASTERN INDIANA...WESTERN OHIO AND CENTRAL LOWER MICHIGAN... ...SUMMARY... Damaging to severe thunderstorm gusts are possible today over parts of the Lower Michigan/southern Great Lakes region, and the eastern Gulf Coastal Plain. ...Synopsis... In mid/upper levels, mean troughing will shift eastward into the central CONUS, as northern- and southern-stream perturbations move into phase. The northern-stream system -- now manifest as a complex, closed cyclone over central Canada -- should remain nearly in place, but with intensification of its southern part into a distinct, closed 500-mb low over the southern MB/SK line by 18Z today. The low then should dig southeastward and eastward over the northern international border region, reaching northern MN and adjoining northwestern ON by 12Z tomorrow. To its southeast, a mid/upper-level cyclone over IA is devolving into an open-wave trough, and will pivot across the upper Mississippi Valley today. By 00Z, that trough should extend from western Lake Superior across WI to northwestern IN. By 12Z, a weakened version will have ejected to northern ON. In the southern stream, a series of mostly low-amplitude shortwave troughs and vorticity maxima will pivot from the Desert Southwest across TX to the lower Mississippi and Tennessee Valley regions, shifting that part of the larger-scale trough to Coahuila and west-central TX by the end of the period. The 11Z surface analysis showed a strong/sub-989-mb low over west- central WI, with polar cold front across western IL, to near MEM, then southwestward over southwestern LA and the northwestern Gulf. The low should occlude and move northeastward to near MQT by 00Z, with polar front overtaking a leading/Pacific boundary across eastern Lower MI and western OH, then extending across middle TN to southeastern LA. The outflow-reinforced, Pacific front will shift from its present position over parts of southern AL and northwestern Fl Panhandle eastward across the Southeast, reaching western SC, central GA and the AAF area by 00Z. The combined front should reach central SC, southeastern GA and the FL coastal bend by 12Z. ...Southern Great Lakes, Lower MI... Surface-based convection is expected to develop this afternoon over western parts of the outlook area, in a zone of favorable low-level convergence near the arctic front, into a corridor of diurnal heating behind a plume of morning clouds/precip. Though buoyancy will be modest (MLCAPE generally under 500 J/kg), and much of the convection may not even deepen enough to produce lightning, fast cell motions and downward momentum transport from intense flow aloft may result in sporadic damaging to severe downdrafts. Even with activity being low-topped, 50-60 kt cloud-layer shear vectors aligned nearly parallel to the front will support an organized, quasi-linear convective system (QLCS). Convection should race northeastward across parts of IN, Lower MI and western OH while backbuilding somewhat, spreading a threat for strong/locally severe gusts over the region for a few hours. Activity should weaken this evening as it encounters both weaker ambient theta-e and nocturnal diabatic stabilization. ...Eastern Gulf Coastal Plain... A swath of precip, with scattered embedded thunderstorms, will continue to shift eastward across southern parts of AL/GA and the FL Panhandle through the period. Most of this activity should remain behind the outflow-reinforced front, keeping severe potential marginal. Though the overall threat appears to have decreased for this morning, isolated strong-severe gusts or a brief tornado still are possible with the convection as it shifts eastward across the outlook area through today and tonight. The net vector motion of the boundary remains to the right of flow aloft. Accordingly, anafrontal convective behavior has persisted for several hours as cells form either on the boundary or just to its east, then move to the cold side before deepening substantially. Isolated/brief strengthening of any such cells to severe limits remains possible, but conditional. Farther east, forecast soundings reasonably suggest that elevated buoyancy developing this afternoon and evening will transition to effectively surface-based late overnight (after about 08Z), and spread inland across the eastern Panhandle, coastal bend and southern GA region ahead of the boundary. A wind shift near the surface, from southeasterly off the relatively stable FL Peninsula to southerly and south-southwesterly off the Gulf, appears responsible for that, and may increase boundary-layer moisture/theta-e enough to yield 500-1000 J/kg MLCAPE. Some reintensification of the convection therefore is possible for a few hours before the start of the day-2 period. ...Central AZ... Isolated to widely scattered thunderstorms are expected today, particularly along and north of the Mogollon Rim. A few cells may produce strong gusts or small hail. The last in a series of shortwaves -- apparent in moisture-channel imagery over the Sierra and western NV -- should shift southeastward across this region today, contributing to cold air aloft (-25 deg C or less at 500 mb) and steep midlevel lapse rates. Meanwhile, diurnal heating of higher elevations on/above the rim will destabilize the boundary later and remove CINH, contributing to a field of up to about 500 J/kg MLCAPE. While low/middle-level flow will be nearly unidirectional and not very strong (generally less than 25 kt from surface to 500 mb), with effective-shear magnitudes only around 20-30 kt, intense upper/anvil-level flow may aid with some storm organization. Severe potential appears too low and conditional for an outlook area at this time. ..Edwards/Leitman.. 03/26/2024 Read more View the full article
  21. Day 4-8 Outlook Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0400 AM CDT Tue Mar 26 2024 Valid 291200Z - 031200Z ...DISCUSSION... The potential for severe thunderstorms across the CONUS appears low from Day 4/Friday into at least Day 5/Saturday. An upper trough/low should dig southward along/near the West Coast in this time frame. Low-level moisture is forecast to gradually return northward across the southern/central Plains, lower/mid MS Valley, and OH Valley through the upcoming weekend. Medium-range guidance is starting to come into better agreement regarding the evolution and eventual ejection of this upper trough/low across the western and central states, with a more positively tilted solution somewhat more probable based on latest ensemble guidance. Regardless, it seems likely that a substantial warm sector will be in place across much of the southern Plains into the lower/mid MS Valley, and perhaps even the OH Valley by Day 6/Sunday and Day 7/Monday. If a northern-stream upper trough over central Canada can phase with the ejecting lower-latitude trough over the western CONUS, as some guidance suggests, then a more organized severe threat may exist, focused on Day 7/Monday and Day 8/Tuesday. At this point, the regions of interest include locations along/east of a surface dryline over the southern/central Plains, and along/south of a warm front draped across the OH Valley. Both instability and deep-layer shear appear strong enough for severe convection. But, there are still some substantial differences in the location of greatest severe risk next Monday and Tuesday. Trends in guidance will be closely monitored. If deterministic and ensemble guidance can come into better agreement regarding the evolution of the upper trough, along with related surface features, then a broad 15% severe area may be needed for next Monday and/or Tuesday in later outlooks. Read more View the full article
  22. Day 4-8 Outlook Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0400 AM CDT Tue Mar 26 2024 Valid 291200Z - 031200Z ...DISCUSSION... The potential for severe thunderstorms across the CONUS appears low from Day 4/Friday into at least Day 5/Saturday. An upper trough/low should dig southward along/near the West Coast in this time frame. Low-level moisture is forecast to gradually return northward across the southern/central Plains, lower/mid MS Valley, and OH Valley through the upcoming weekend. Medium-range guidance is starting to come into better agreement regarding the evolution and eventual ejection of this upper trough/low across the western and central states, with a more positively tilted solution somewhat more probable based on latest ensemble guidance. Regardless, it seems likely that a substantial warm sector will be in place across much of the southern Plains into the lower/mid MS Valley, and perhaps even the OH Valley by Day 6/Sunday and Day 7/Monday. If a northern-stream upper trough over central Canada can phase with the ejecting lower-latitude trough over the western CONUS, as some guidance suggests, then a more organized severe threat may exist, focused on Day 7/Monday and Day 8/Tuesday. At this point, the regions of interest include locations along/east of a surface dryline over the southern/central Plains, and along/south of a warm front draped across the OH Valley. Both instability and deep-layer shear appear strong enough for severe convection. But, there are still some substantial differences in the location of greatest severe risk next Monday and Tuesday. Trends in guidance will be closely monitored. If deterministic and ensemble guidance can come into better agreement regarding the evolution of the upper trough, along with related surface features, then a broad 15% severe area may be needed for next Monday and/or Tuesday in later outlooks. Read more View the full article
  23. Day 4-8 Outlook Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0400 AM CDT Tue Mar 26 2024 Valid 291200Z - 031200Z ...DISCUSSION... The potential for severe thunderstorms across the CONUS appears low from Day 4/Friday into at least Day 5/Saturday. An upper trough/low should dig southward along/near the West Coast in this time frame. Low-level moisture is forecast to gradually return northward across the southern/central Plains, lower/mid MS Valley, and OH Valley through the upcoming weekend. Medium-range guidance is starting to come into better agreement regarding the evolution and eventual ejection of this upper trough/low across the western and central states, with a more positively tilted solution somewhat more probable based on latest ensemble guidance. Regardless, it seems likely that a substantial warm sector will be in place across much of the southern Plains into the lower/mid MS Valley, and perhaps even the OH Valley by Day 6/Sunday and Day 7/Monday. If a northern-stream upper trough over central Canada can phase with the ejecting lower-latitude trough over the western CONUS, as some guidance suggests, then a more organized severe threat may exist, focused on Day 7/Monday and Day 8/Tuesday. At this point, the regions of interest include locations along/east of a surface dryline over the southern/central Plains, and along/south of a warm front draped across the OH Valley. Both instability and deep-layer shear appear strong enough for severe convection. But, there are still some substantial differences in the location of greatest severe risk next Monday and Tuesday. Trends in guidance will be closely monitored. If deterministic and ensemble guidance can come into better agreement regarding the evolution of the upper trough, along with related surface features, then a broad 15% severe area may be needed for next Monday and/or Tuesday in later outlooks. Read more View the full article
  24. SPC 0730Z Day 3 Outlook Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0220 AM CDT Tue Mar 26 2024 Valid 281200Z - 291200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not forecast on Thursday. ...Synopsis and Discussion... A southern-stream upper trough will continue to progress eastward over the Gulf and Southeast on Thursday. A weak surface low near the NC/SC Coast should likewise develop eastward over the western Atlantic through the day, while a trailing cold front sweeps southeastward across FL. Limited low-level convergence along this front should keep any thunderstorm potential quite isolated, and the overall threat appears too low to include any severe probabilities at this time. Generally elevated thunderstorms may also occur across parts of coastal GA/SC/NC through early Thursday afternoon, as pronounced forcing for ascent associated with the upper trough overlaps weak MUCAPE. Occasional lightning flashes may also occur Thursday across parts of both the coastal and interior Northwest, as well as northern California. An upper trough is forecast to move eastward across these areas through the period, with cold mid-level temperatures (around -24 to -30C at 500 mb) aiding in weak destabilization. Limited moisture and instability are expected to preclude severe thunderstorms. ..Gleason.. 03/26/2024 Read more View the full article
  25. SPC 0730Z Day 3 Outlook Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0220 AM CDT Tue Mar 26 2024 Valid 281200Z - 291200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not forecast on Thursday. ...Synopsis and Discussion... A southern-stream upper trough will continue to progress eastward over the Gulf and Southeast on Thursday. A weak surface low near the NC/SC Coast should likewise develop eastward over the western Atlantic through the day, while a trailing cold front sweeps southeastward across FL. Limited low-level convergence along this front should keep any thunderstorm potential quite isolated, and the overall threat appears too low to include any severe probabilities at this time. Generally elevated thunderstorms may also occur across parts of coastal GA/SC/NC through early Thursday afternoon, as pronounced forcing for ascent associated with the upper trough overlaps weak MUCAPE. Occasional lightning flashes may also occur Thursday across parts of both the coastal and interior Northwest, as well as northern California. An upper trough is forecast to move eastward across these areas through the period, with cold mid-level temperatures (around -24 to -30C at 500 mb) aiding in weak destabilization. Limited moisture and instability are expected to preclude severe thunderstorms. ..Gleason.. 03/26/2024 Read more View the full article
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