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NorthGeorgiaWX

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  1. SPC Day 2 Fire Weather Outlook Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0147 PM CDT Thu Mar 28 2024 Valid 291200Z - 301200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF EASTERN NEW MEXICO... ...19z Update... Added critical area for parts of eastern NM. Confidence has increased that more widespread winds of 20-25 mph will overlap with RH below 10% for several hours Friday afternoon. While some uncertainty regarding fuel states remains, drying today and delayed green up in fine fuels west of the Caprock should support some critical fire-weather risk across parts of eastern NM and potentially the TX Panhandle. Elsewhere, southwest surface winds and low humidity should support widespread elevated fire-weather potential over much of the southern High Plains and into southern CO. See the previous discussion for more information. ..Lyons.. 03/28/2024 .PREV DISCUSSION... /ISSUED 0154 AM CDT Thu Mar 28 2024/ ...Synopsis... Surface cyclone development is expected across the southern High Plains as a mid-level trough amplifies across the Southwest tomorrow (Friday). Downslope flow will increase in the process, with much of the southern High Plains experiencing widespread 10-15 percent RH and 15-20 mph sustained westerly surface winds by afternoon peak heating. Given multiple days of dry and windy conditions, fine fuels will continue to cure further, supporting at least widespread "high-end" Elevated conditions, especially over eastern New Mexico into western Texas. If fuel receptiveness increases at a greater rate than currently anticipated, Critical highlights may be needed in future outlooks. ...Please see www.spc.noaa.gov/fire for graphic product... Read more View the full article
  2. Frost Advisory issued March 28 at 2:39PM EDT until March 29 at 8:00AM EDT by NWS Peachtree City GAView the full article
  3. Special Weather Statement issued March 28 at 2:33PM EDT by NWS Greenville-Spartanburg SCView the full article
  4. Special Weather Statement issued March 28 at 2:22PM EDT by NWS Peachtree City GAView the full article
  5. SPC 1730Z Day 2 Outlook Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1155 AM CDT Thu Mar 28 2024 Valid 291200Z - 301200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected on Friday. ...Synopsis... A deep upper-level trough over the eastern CONUS is forecast to continue moving eastward on Friday. Upstream, an upper-level trough will continue to amplify across the West, as a deep-layer cyclone moves southeastward just offshore of the central CA coast. Between the eastern and western troughs, multiple low-amplitude shortwaves will move northeastward across parts of the central/northern Plains and upper Midwest. The greatest relative thunderstorm potential is currently expected over parts of the Midwest/Mid-Upper MS Valley within a warm-advection regime, and near the central CA coast in association with the offshore cyclone. ...Parts of the Midwest/Mid-Upper MS Valley... Modest low-level moisture return (surface dewpoints in the low 50s F) is expected across parts of MO/IA into western/northern IL, as a weak surface low moves from the east-central Great Plains toward southern WI. Modest MLCAPE (increasing to near/above 500 J/kg) may develop in the warm sector of the surface low, though capping is currently expected to limit the potential for surface-based storm development. Elevated thunderstorm development will become increasingly possible with time Friday evening, within a low-level warm-advection regime. While increasing effective shear will be sufficient for some storm organization, rather weak elevated buoyancy (MUCAPE generally 500-1000 J/kg) is currently expected to limit severe-hail potential. If elevated buoyancy trends larger than currently forecast, and/or if surface-based storm development becomes more of a concern, then low-end severe probabilities may eventually be needed. ..Dean.. 03/28/2024 Read more View the full article
  6. SPC Day 1 Fire Weather Outlook Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Thu Mar 28 2024 Valid 281700Z - 291200Z ...17z Update... No major changes have been assessed to the outlook. The Elevated area was expanded slightly south and east across parts of the TX Big Bend. Here, southerly surface winds of 15-20 mph will briefly overlap with RH below 20%. Brief elevated fire-weather conditions are possible given recent drying of fuels. ..Lyons.. 03/28/2024 .PREV DISCUSSION... /ISSUED 0135 AM CDT Thu Mar 28 2024/ ...Synopsis... Surface lee troughing will intensify over the southern High Plains today in tandem with an increase in mid-level flow/upper-level support. Dry downslope flow is expected across the southern High Plains during the afternoon. Across eastern New Mexico into western Texas, 15-25 mph sustained southwesterly surface winds and 10-20 percent RH atop modestly receptive fuels will support some wildfire spread potential, necessitating the maintenance of Elevated highlights. ...Please see www.spc.noaa.gov/fire for graphic product... Read more View the full article
  7. SPC Day 1 Fire Weather Outlook Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Thu Mar 28 2024 Valid 281700Z - 291200Z ...17z Update... No major changes have been assessed to the outlook. The Elevated area was expanded slightly south and east across parts of the TX Big Bend. Here, southerly surface winds of 15-20 mph will briefly overlap with RH below 20%. Brief elevated fire-weather conditions are possible given recent drying of fuels. ..Lyons.. 03/28/2024 .PREV DISCUSSION... /ISSUED 0135 AM CDT Thu Mar 28 2024/ ...Synopsis... Surface lee troughing will intensify over the southern High Plains today in tandem with an increase in mid-level flow/upper-level support. Dry downslope flow is expected across the southern High Plains during the afternoon. Across eastern New Mexico into western Texas, 15-25 mph sustained southwesterly surface winds and 10-20 percent RH atop modestly receptive fuels will support some wildfire spread potential, necessitating the maintenance of Elevated highlights. ...Please see www.spc.noaa.gov/fire for graphic product... Read more View the full article
  8. SPC 1630Z Day 1 Outlook Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1118 AM CDT Thu Mar 28 2024 Valid 281630Z - 291200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected. Relatively dry and stable conditions are expected today over most of the CONUS, with only a few areas of thunderstorm activity. A cold front will depart the Carolinas and FL region this afternoon, with associated showers and thunderstorms moving offshore by mid-afternoon. Other scattered showers and isolated thunderstorms may occur over parts of the northwestern US where cold mid-level temperatures and marginal afternoon instability will be present. No severe storms are anticipated in either region. ..Hart/Thornton.. 03/28/2024 Read more View the full article
  9. SPC 1630Z Day 1 Outlook Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1118 AM CDT Thu Mar 28 2024 Valid 281630Z - 291200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected. Relatively dry and stable conditions are expected today over most of the CONUS, with only a few areas of thunderstorm activity. A cold front will depart the Carolinas and FL region this afternoon, with associated showers and thunderstorms moving offshore by mid-afternoon. Other scattered showers and isolated thunderstorms may occur over parts of the northwestern US where cold mid-level temperatures and marginal afternoon instability will be present. No severe storms are anticipated in either region. ..Hart/Thornton.. 03/28/2024 Read more View the full article
  10. Flood Warning issued March 28 at 10:24AM EDT by NWS Charleston SCView the full article
  11. Flood Warning issued March 28 at 10:24AM EDT by NWS Charleston SCView the full article
  12. Flood Warning issued March 28 at 9:18AM EDT by NWS Jacksonville FLView the full article
  13. Flood Warning issued March 28 at 9:17AM EDT by NWS Jacksonville FLView the full article
  14. SPC 1300Z Day 1 Outlook Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0747 AM CDT Thu Mar 28 2024 Valid 281300Z - 291200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected. ...Synopsis/Discussion... The mid/upper-level pattern will remain progressive, but deamplify temporarily, through the end of the period. This will occur as a strong synoptic-scale trough -- initially extending from northern ON across the Ohio/Tennessee Valleys to the central Gulf -- pivots preferentially faster eastward in its southern parts. By 12Z tomorrow, the synoptic trough will become negatively tilted from a low over James bay across the NYC area, then to a basal shortwave trough offshore from the Atlantic Coast farther south. That shortwave -- now apparent in moisture-channel imagery over the central Gulf Coast -- will follow a cold front offshore. Before that, however, a few more hours of general thunder potential are possible over coastal NC, including the sounds and Outer Banks. Isolated thunderstorms also are possible over much of the FL Peninsula amid favorable moisture along/ahead of the front, but with coverage limited by modest lift. Mid/upper-level winds and deep shear remain strong across the region, and a few cells moving through a diurnally destabilizing thermodynamic profile inland may produce strong gusts or small hail. Elsewhere, a large mid/upper-level cyclone was centered about 300 nm west of HQM, with synoptic trough extending south-southeastward offshore from the West Coast. As a strengthening shortwave trough south of the Gulf of Alaska digs southeastward to west of north- central CA through the period, the cyclone will weaken, but the larger-scale trough will be maintained. Several variably sized/ shaped shortwave perturbations were noted in downstream southwest flow over the Pacific Coast States and Intermountain West. Related large-scale ascent and steep midlevel lapse rates, with patches of weak but adequate low/middle-level moisture, will combine to support isolated general-thunder potential over parts of the West. This includes the Northwest Coast, where the cool but moist Pacific marine layer will underlie coldest air aloft. ..Edwards/Leitman.. 03/28/2024 Read more View the full article
  15. SPC 1300Z Day 1 Outlook Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0747 AM CDT Thu Mar 28 2024 Valid 281300Z - 291200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected. ...Synopsis/Discussion... The mid/upper-level pattern will remain progressive, but deamplify temporarily, through the end of the period. This will occur as a strong synoptic-scale trough -- initially extending from northern ON across the Ohio/Tennessee Valleys to the central Gulf -- pivots preferentially faster eastward in its southern parts. By 12Z tomorrow, the synoptic trough will become negatively tilted from a low over James bay across the NYC area, then to a basal shortwave trough offshore from the Atlantic Coast farther south. That shortwave -- now apparent in moisture-channel imagery over the central Gulf Coast -- will follow a cold front offshore. Before that, however, a few more hours of general thunder potential are possible over coastal NC, including the sounds and Outer Banks. Isolated thunderstorms also are possible over much of the FL Peninsula amid favorable moisture along/ahead of the front, but with coverage limited by modest lift. Mid/upper-level winds and deep shear remain strong across the region, and a few cells moving through a diurnally destabilizing thermodynamic profile inland may produce strong gusts or small hail. Elsewhere, a large mid/upper-level cyclone was centered about 300 nm west of HQM, with synoptic trough extending south-southeastward offshore from the West Coast. As a strengthening shortwave trough south of the Gulf of Alaska digs southeastward to west of north- central CA through the period, the cyclone will weaken, but the larger-scale trough will be maintained. Several variably sized/ shaped shortwave perturbations were noted in downstream southwest flow over the Pacific Coast States and Intermountain West. Related large-scale ascent and steep midlevel lapse rates, with patches of weak but adequate low/middle-level moisture, will combine to support isolated general-thunder potential over parts of the West. This includes the Northwest Coast, where the cool but moist Pacific marine layer will underlie coldest air aloft. ..Edwards/Leitman.. 03/28/2024 Read more View the full article
  16. SPC 1300Z Day 1 Outlook Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0747 AM CDT Thu Mar 28 2024 Valid 281300Z - 291200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected. ...Synopsis/Discussion... The mid/upper-level pattern will remain progressive, but deamplify temporarily, through the end of the period. This will occur as a strong synoptic-scale trough -- initially extending from northern ON across the Ohio/Tennessee Valleys to the central Gulf -- pivots preferentially faster eastward in its southern parts. By 12Z tomorrow, the synoptic trough will become negatively tilted from a low over James bay across the NYC area, then to a basal shortwave trough offshore from the Atlantic Coast farther south. That shortwave -- now apparent in moisture-channel imagery over the central Gulf Coast -- will follow a cold front offshore. Before that, however, a few more hours of general thunder potential are possible over coastal NC, including the sounds and Outer Banks. Isolated thunderstorms also are possible over much of the FL Peninsula amid favorable moisture along/ahead of the front, but with coverage limited by modest lift. Mid/upper-level winds and deep shear remain strong across the region, and a few cells moving through a diurnally destabilizing thermodynamic profile inland may produce strong gusts or small hail. Elsewhere, a large mid/upper-level cyclone was centered about 300 nm west of HQM, with synoptic trough extending south-southeastward offshore from the West Coast. As a strengthening shortwave trough south of the Gulf of Alaska digs southeastward to west of north- central CA through the period, the cyclone will weaken, but the larger-scale trough will be maintained. Several variably sized/ shaped shortwave perturbations were noted in downstream southwest flow over the Pacific Coast States and Intermountain West. Related large-scale ascent and steep midlevel lapse rates, with patches of weak but adequate low/middle-level moisture, will combine to support isolated general-thunder potential over parts of the West. This includes the Northwest Coast, where the cool but moist Pacific marine layer will underlie coldest air aloft. ..Edwards/Leitman.. 03/28/2024 Read more View the full article
  17. Day 4-8 Outlook Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0400 AM CDT Thu Mar 28 2024 Valid 311200Z - 051200Z ...DISCUSSION... ...Day 4/Sunday: Mid Mississippi Valley into the Central/Southern Plains... The upper trough/low over the western states should slowly advance eastward towards the Southwest and southern/central High Plains on Sunday. Upper ridging is forecast to remain over the central/ southern Plains through Sunday night, which in tandem with a low-level temperature inversion should tend to suppress most convection. One possible exception may be along a sharpening warm front across MO/IL, where some guidance suggests elevated convection may form either Sunday morning, and/or Sunday night with strong low-level warm advection/lift occurring. Steepening mid-level lapse rates are forecast to overspread the mid MS Valley from the southwest through the period. These lapse rates, along with increasing moisture/instability in the presence of strong deep-layer shear, may support a risk for isolated supercells with associated threat for large hail. Regardless, confidence remains too low in this mainly elevated convection occurring, given upper ridging persisting, to add a 15% severe area for Sunday along/near the warm front in MO/IL at this time. ...Day 5/Monday: Southern/Central Plains into the Mid Mississippi and Ohio Valleys... Even though some differences remain in medium-range guidance regarding the ejection of an upper trough over the central CONUS on Monday, confidence has increased in the general location of relevant surface features, including the primary low, position of a southward-extending dryline, and northward extent of the warm front into the OH Valley. Even though the overall upper trough orientation may remain somewhat positively tilted, most deterministic guidance shows that a mid-level speed max and associated shortwave trough will eject northeastward over the southern/central Plains through Monday evening. Low-level mass response should encourage the eastward development of a surface low to the OK/KS vicinity in a similar time frame. Favorable low-level trajectories emanating from the Gulf will act to increase low-level moisture in tandem with steepening mid-level lapse rates and daytime heating across a broad warm sector extending from the southern/central Plains into the lower/mid MS Valley and OH Valley. A favorable thermodynamic and kinematic environment for organized severe convection will exist across much of these regions, with supercells capable of producing large hail and tornadoes possible initially. With time Monday evening/night, some upscale growth seems probable across the mid MS and OH Valleys, as mid-level flow should become increasingly parallel to a surface cold front. Therefore, a 15% severe area has been introduced for Monday where confidence is greatest that robust convection will develop in a parameter space characterized by weak/moderate instability and strong deep-layer shear. A nocturnal minimum in severe convective potential may be realized Monday night into early Tuesday morning across parts of the lower MS Valley into Mid-South, given the positively tilted nature of the upper trough. ...Day 6/Tuesday: Ohio/Tennessee Valleys into the Appalachians... Some severe threat should continue Tuesday over parts of the OH/TN Valleys into the Appalachians as the upper trough continues eastward. Even though there is still some uncertainty with the exact placement of the primary surface low and evolution of the upper trough, enough confidence exists in a fairly narrow corridor across these regions to add a 15% severe area for Tuesday. Rich low-level moisture should be in place ahead of an eastward-moving cold front. Redevelopment and/or re-intensification of convection seems probable by Tuesday afternoon. Strong deep-layer shear and weak instability should be sufficient for organized severe convection posing some threat for damaging winds, and perhaps tornadoes given the forecast strength of a low-level jet focused over parts of the OH/TN Valleys. The northward extent of the severe risk across OH and vicinity remains uncertain, as the placement of the warm front varies in model guidance. Similarly, convection should eventually encounter a less unstable airmass across the Appalachians. But, an isolated severe risk may continue Tuesday evening into early Wednesday morning across the southern/central Appalachians into portions of the Southeast. ...Day 7/Wednesday and Day 8/Thursday... Predictability remains too low to include a 15% severe delineation for Wednesday across the Mid-Atlantic/Southeast along/ahead of a cold front. By this extended time frame, there are significant differences in model guidance regarding the evolution of the upper trough, including its possible interaction/merging with a northern-stream trough, and placement of relevant surface features. Still, at least an isolated severe risk may persist Wednesday along/ahead of the eastward-sweeping cold front. Once this front clears the East Coast, severe potential appears minimal across the CONUS next Thursday. Read more View the full article
  18. Day 4-8 Outlook Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0400 AM CDT Thu Mar 28 2024 Valid 311200Z - 051200Z ...DISCUSSION... ...Day 4/Sunday: Mid Mississippi Valley into the Central/Southern Plains... The upper trough/low over the western states should slowly advance eastward towards the Southwest and southern/central High Plains on Sunday. Upper ridging is forecast to remain over the central/ southern Plains through Sunday night, which in tandem with a low-level temperature inversion should tend to suppress most convection. One possible exception may be along a sharpening warm front across MO/IL, where some guidance suggests elevated convection may form either Sunday morning, and/or Sunday night with strong low-level warm advection/lift occurring. Steepening mid-level lapse rates are forecast to overspread the mid MS Valley from the southwest through the period. These lapse rates, along with increasing moisture/instability in the presence of strong deep-layer shear, may support a risk for isolated supercells with associated threat for large hail. Regardless, confidence remains too low in this mainly elevated convection occurring, given upper ridging persisting, to add a 15% severe area for Sunday along/near the warm front in MO/IL at this time. ...Day 5/Monday: Southern/Central Plains into the Mid Mississippi and Ohio Valleys... Even though some differences remain in medium-range guidance regarding the ejection of an upper trough over the central CONUS on Monday, confidence has increased in the general location of relevant surface features, including the primary low, position of a southward-extending dryline, and northward extent of the warm front into the OH Valley. Even though the overall upper trough orientation may remain somewhat positively tilted, most deterministic guidance shows that a mid-level speed max and associated shortwave trough will eject northeastward over the southern/central Plains through Monday evening. Low-level mass response should encourage the eastward development of a surface low to the OK/KS vicinity in a similar time frame. Favorable low-level trajectories emanating from the Gulf will act to increase low-level moisture in tandem with steepening mid-level lapse rates and daytime heating across a broad warm sector extending from the southern/central Plains into the lower/mid MS Valley and OH Valley. A favorable thermodynamic and kinematic environment for organized severe convection will exist across much of these regions, with supercells capable of producing large hail and tornadoes possible initially. With time Monday evening/night, some upscale growth seems probable across the mid MS and OH Valleys, as mid-level flow should become increasingly parallel to a surface cold front. Therefore, a 15% severe area has been introduced for Monday where confidence is greatest that robust convection will develop in a parameter space characterized by weak/moderate instability and strong deep-layer shear. A nocturnal minimum in severe convective potential may be realized Monday night into early Tuesday morning across parts of the lower MS Valley into Mid-South, given the positively tilted nature of the upper trough. ...Day 6/Tuesday: Ohio/Tennessee Valleys into the Appalachians... Some severe threat should continue Tuesday over parts of the OH/TN Valleys into the Appalachians as the upper trough continues eastward. Even though there is still some uncertainty with the exact placement of the primary surface low and evolution of the upper trough, enough confidence exists in a fairly narrow corridor across these regions to add a 15% severe area for Tuesday. Rich low-level moisture should be in place ahead of an eastward-moving cold front. Redevelopment and/or re-intensification of convection seems probable by Tuesday afternoon. Strong deep-layer shear and weak instability should be sufficient for organized severe convection posing some threat for damaging winds, and perhaps tornadoes given the forecast strength of a low-level jet focused over parts of the OH/TN Valleys. The northward extent of the severe risk across OH and vicinity remains uncertain, as the placement of the warm front varies in model guidance. Similarly, convection should eventually encounter a less unstable airmass across the Appalachians. But, an isolated severe risk may continue Tuesday evening into early Wednesday morning across the southern/central Appalachians into portions of the Southeast. ...Day 7/Wednesday and Day 8/Thursday... Predictability remains too low to include a 15% severe delineation for Wednesday across the Mid-Atlantic/Southeast along/ahead of a cold front. By this extended time frame, there are significant differences in model guidance regarding the evolution of the upper trough, including its possible interaction/merging with a northern-stream trough, and placement of relevant surface features. Still, at least an isolated severe risk may persist Wednesday along/ahead of the eastward-sweeping cold front. Once this front clears the East Coast, severe potential appears minimal across the CONUS next Thursday. Read more View the full article
  19. Day 4-8 Outlook Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0400 AM CDT Thu Mar 28 2024 Valid 311200Z - 051200Z ...DISCUSSION... ...Day 4/Sunday: Mid Mississippi Valley into the Central/Southern Plains... The upper trough/low over the western states should slowly advance eastward towards the Southwest and southern/central High Plains on Sunday. Upper ridging is forecast to remain over the central/ southern Plains through Sunday night, which in tandem with a low-level temperature inversion should tend to suppress most convection. One possible exception may be along a sharpening warm front across MO/IL, where some guidance suggests elevated convection may form either Sunday morning, and/or Sunday night with strong low-level warm advection/lift occurring. Steepening mid-level lapse rates are forecast to overspread the mid MS Valley from the southwest through the period. These lapse rates, along with increasing moisture/instability in the presence of strong deep-layer shear, may support a risk for isolated supercells with associated threat for large hail. Regardless, confidence remains too low in this mainly elevated convection occurring, given upper ridging persisting, to add a 15% severe area for Sunday along/near the warm front in MO/IL at this time. ...Day 5/Monday: Southern/Central Plains into the Mid Mississippi and Ohio Valleys... Even though some differences remain in medium-range guidance regarding the ejection of an upper trough over the central CONUS on Monday, confidence has increased in the general location of relevant surface features, including the primary low, position of a southward-extending dryline, and northward extent of the warm front into the OH Valley. Even though the overall upper trough orientation may remain somewhat positively tilted, most deterministic guidance shows that a mid-level speed max and associated shortwave trough will eject northeastward over the southern/central Plains through Monday evening. Low-level mass response should encourage the eastward development of a surface low to the OK/KS vicinity in a similar time frame. Favorable low-level trajectories emanating from the Gulf will act to increase low-level moisture in tandem with steepening mid-level lapse rates and daytime heating across a broad warm sector extending from the southern/central Plains into the lower/mid MS Valley and OH Valley. A favorable thermodynamic and kinematic environment for organized severe convection will exist across much of these regions, with supercells capable of producing large hail and tornadoes possible initially. With time Monday evening/night, some upscale growth seems probable across the mid MS and OH Valleys, as mid-level flow should become increasingly parallel to a surface cold front. Therefore, a 15% severe area has been introduced for Monday where confidence is greatest that robust convection will develop in a parameter space characterized by weak/moderate instability and strong deep-layer shear. A nocturnal minimum in severe convective potential may be realized Monday night into early Tuesday morning across parts of the lower MS Valley into Mid-South, given the positively tilted nature of the upper trough. ...Day 6/Tuesday: Ohio/Tennessee Valleys into the Appalachians... Some severe threat should continue Tuesday over parts of the OH/TN Valleys into the Appalachians as the upper trough continues eastward. Even though there is still some uncertainty with the exact placement of the primary surface low and evolution of the upper trough, enough confidence exists in a fairly narrow corridor across these regions to add a 15% severe area for Tuesday. Rich low-level moisture should be in place ahead of an eastward-moving cold front. Redevelopment and/or re-intensification of convection seems probable by Tuesday afternoon. Strong deep-layer shear and weak instability should be sufficient for organized severe convection posing some threat for damaging winds, and perhaps tornadoes given the forecast strength of a low-level jet focused over parts of the OH/TN Valleys. The northward extent of the severe risk across OH and vicinity remains uncertain, as the placement of the warm front varies in model guidance. Similarly, convection should eventually encounter a less unstable airmass across the Appalachians. But, an isolated severe risk may continue Tuesday evening into early Wednesday morning across the southern/central Appalachians into portions of the Southeast. ...Day 7/Wednesday and Day 8/Thursday... Predictability remains too low to include a 15% severe delineation for Wednesday across the Mid-Atlantic/Southeast along/ahead of a cold front. By this extended time frame, there are significant differences in model guidance regarding the evolution of the upper trough, including its possible interaction/merging with a northern-stream trough, and placement of relevant surface features. Still, at least an isolated severe risk may persist Wednesday along/ahead of the eastward-sweeping cold front. Once this front clears the East Coast, severe potential appears minimal across the CONUS next Thursday. Read more View the full article
  20. Day 4-8 Outlook Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0400 AM CDT Thu Mar 28 2024 Valid 311200Z - 051200Z ...DISCUSSION... ...Day 4/Sunday: Mid Mississippi Valley into the Central/Southern Plains... The upper trough/low over the western states should slowly advance eastward towards the Southwest and southern/central High Plains on Sunday. Upper ridging is forecast to remain over the central/ southern Plains through Sunday night, which in tandem with a low-level temperature inversion should tend to suppress most convection. One possible exception may be along a sharpening warm front across MO/IL, where some guidance suggests elevated convection may form either Sunday morning, and/or Sunday night with strong low-level warm advection/lift occurring. Steepening mid-level lapse rates are forecast to overspread the mid MS Valley from the southwest through the period. These lapse rates, along with increasing moisture/instability in the presence of strong deep-layer shear, may support a risk for isolated supercells with associated threat for large hail. Regardless, confidence remains too low in this mainly elevated convection occurring, given upper ridging persisting, to add a 15% severe area for Sunday along/near the warm front in MO/IL at this time. ...Day 5/Monday: Southern/Central Plains into the Mid Mississippi and Ohio Valleys... Even though some differences remain in medium-range guidance regarding the ejection of an upper trough over the central CONUS on Monday, confidence has increased in the general location of relevant surface features, including the primary low, position of a southward-extending dryline, and northward extent of the warm front into the OH Valley. Even though the overall upper trough orientation may remain somewhat positively tilted, most deterministic guidance shows that a mid-level speed max and associated shortwave trough will eject northeastward over the southern/central Plains through Monday evening. Low-level mass response should encourage the eastward development of a surface low to the OK/KS vicinity in a similar time frame. Favorable low-level trajectories emanating from the Gulf will act to increase low-level moisture in tandem with steepening mid-level lapse rates and daytime heating across a broad warm sector extending from the southern/central Plains into the lower/mid MS Valley and OH Valley. A favorable thermodynamic and kinematic environment for organized severe convection will exist across much of these regions, with supercells capable of producing large hail and tornadoes possible initially. With time Monday evening/night, some upscale growth seems probable across the mid MS and OH Valleys, as mid-level flow should become increasingly parallel to a surface cold front. Therefore, a 15% severe area has been introduced for Monday where confidence is greatest that robust convection will develop in a parameter space characterized by weak/moderate instability and strong deep-layer shear. A nocturnal minimum in severe convective potential may be realized Monday night into early Tuesday morning across parts of the lower MS Valley into Mid-South, given the positively tilted nature of the upper trough. ...Day 6/Tuesday: Ohio/Tennessee Valleys into the Appalachians... Some severe threat should continue Tuesday over parts of the OH/TN Valleys into the Appalachians as the upper trough continues eastward. Even though there is still some uncertainty with the exact placement of the primary surface low and evolution of the upper trough, enough confidence exists in a fairly narrow corridor across these regions to add a 15% severe area for Tuesday. Rich low-level moisture should be in place ahead of an eastward-moving cold front. Redevelopment and/or re-intensification of convection seems probable by Tuesday afternoon. Strong deep-layer shear and weak instability should be sufficient for organized severe convection posing some threat for damaging winds, and perhaps tornadoes given the forecast strength of a low-level jet focused over parts of the OH/TN Valleys. The northward extent of the severe risk across OH and vicinity remains uncertain, as the placement of the warm front varies in model guidance. Similarly, convection should eventually encounter a less unstable airmass across the Appalachians. But, an isolated severe risk may continue Tuesday evening into early Wednesday morning across the southern/central Appalachians into portions of the Southeast. ...Day 7/Wednesday and Day 8/Thursday... Predictability remains too low to include a 15% severe delineation for Wednesday across the Mid-Atlantic/Southeast along/ahead of a cold front. By this extended time frame, there are significant differences in model guidance regarding the evolution of the upper trough, including its possible interaction/merging with a northern-stream trough, and placement of relevant surface features. Still, at least an isolated severe risk may persist Wednesday along/ahead of the eastward-sweeping cold front. Once this front clears the East Coast, severe potential appears minimal across the CONUS next Thursday. Read more View the full article
  21. Special Weather Statement issued March 28 at 3:42AM EDT by NWS Peachtree City GAView the full article
  22. Special Weather Statement issued March 28 at 3:32AM EDT by NWS Greenville-Spartanburg SCView the full article
  23. SPC 0730Z Day 3 Outlook Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0226 AM CDT Thu Mar 28 2024 Valid 301200Z - 311200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not forecast on Saturday. ...Synopsis and Discussion... A deep, closed upper low initially off the coast of central CA should move slowly southward along/near the southern CA Coast on Saturday. Cold mid-level temperatures and strong forcing for ascent associated with an enhanced mid/upper-level jet should support weak instability, and the potential for isolated lighting flashes with any low-topped convection that can develop from parts of central into southern CA. Organized severe thunderstorms appear unlikely across this region given the meager MUCAPE forecast. Isolated thunderstorms may occur Saturday over parts of the southern Great Lakes/OH Valley, as a low-amplitude shortwave trough moves east-southeastward across these areas. A weak surface low is also forecast to develop eastward over this region in tandem with the shortwave trough. Limited low-level moisture, with surface dewpoints generally in the low 50s, should temper how much instability can develop through Saturday afternoon given the presence of modest to poor mid-level lapse rates. This will likely hinder the overall severe threat across the OH Valley, even though deep-layer shear conditionally supports the potential for organized convection. Finally, occasional lightning flashes may occur with elevated convection that develops late Saturday night into early Sunday morning across parts of NE into southwestern IA and northern MO. Low-level moisture is expected to gradually return northward across the southern/central Plains through the day, and this area will be on northern fringe of this process. Strong forcing associated with a southerly low-level jet may provide sufficient lift for parcels to reach their LFC. Still, forecast MUCAPE appears too weak to support a meaningful hail threat through the end of the period (early Sunday morning). ..Gleason.. 03/28/2024 Read more View the full article
  24. SPC 0730Z Day 3 Outlook Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0226 AM CDT Thu Mar 28 2024 Valid 301200Z - 311200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not forecast on Saturday. ...Synopsis and Discussion... A deep, closed upper low initially off the coast of central CA should move slowly southward along/near the southern CA Coast on Saturday. Cold mid-level temperatures and strong forcing for ascent associated with an enhanced mid/upper-level jet should support weak instability, and the potential for isolated lighting flashes with any low-topped convection that can develop from parts of central into southern CA. Organized severe thunderstorms appear unlikely across this region given the meager MUCAPE forecast. Isolated thunderstorms may occur Saturday over parts of the southern Great Lakes/OH Valley, as a low-amplitude shortwave trough moves east-southeastward across these areas. A weak surface low is also forecast to develop eastward over this region in tandem with the shortwave trough. Limited low-level moisture, with surface dewpoints generally in the low 50s, should temper how much instability can develop through Saturday afternoon given the presence of modest to poor mid-level lapse rates. This will likely hinder the overall severe threat across the OH Valley, even though deep-layer shear conditionally supports the potential for organized convection. Finally, occasional lightning flashes may occur with elevated convection that develops late Saturday night into early Sunday morning across parts of NE into southwestern IA and northern MO. Low-level moisture is expected to gradually return northward across the southern/central Plains through the day, and this area will be on northern fringe of this process. Strong forcing associated with a southerly low-level jet may provide sufficient lift for parcels to reach their LFC. Still, forecast MUCAPE appears too weak to support a meaningful hail threat through the end of the period (early Sunday morning). ..Gleason.. 03/28/2024 Read more View the full article
  25. SPC 0730Z Day 3 Outlook Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0226 AM CDT Thu Mar 28 2024 Valid 301200Z - 311200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not forecast on Saturday. ...Synopsis and Discussion... A deep, closed upper low initially off the coast of central CA should move slowly southward along/near the southern CA Coast on Saturday. Cold mid-level temperatures and strong forcing for ascent associated with an enhanced mid/upper-level jet should support weak instability, and the potential for isolated lighting flashes with any low-topped convection that can develop from parts of central into southern CA. Organized severe thunderstorms appear unlikely across this region given the meager MUCAPE forecast. Isolated thunderstorms may occur Saturday over parts of the southern Great Lakes/OH Valley, as a low-amplitude shortwave trough moves east-southeastward across these areas. A weak surface low is also forecast to develop eastward over this region in tandem with the shortwave trough. Limited low-level moisture, with surface dewpoints generally in the low 50s, should temper how much instability can develop through Saturday afternoon given the presence of modest to poor mid-level lapse rates. This will likely hinder the overall severe threat across the OH Valley, even though deep-layer shear conditionally supports the potential for organized convection. Finally, occasional lightning flashes may occur with elevated convection that develops late Saturday night into early Sunday morning across parts of NE into southwestern IA and northern MO. Low-level moisture is expected to gradually return northward across the southern/central Plains through the day, and this area will be on northern fringe of this process. Strong forcing associated with a southerly low-level jet may provide sufficient lift for parcels to reach their LFC. Still, forecast MUCAPE appears too weak to support a meaningful hail threat through the end of the period (early Sunday morning). ..Gleason.. 03/28/2024 Read more View the full article
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