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MFoland

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  1. SPC 2000Z Day 1 Outlook Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0256 PM CDT Wed Oct 16 2019 Valid 162000Z - 171200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTHERN NEW ENGLAND... ...SUMMARY... Locally gusty/damaging thunderstorm winds may occur over southern New England this evening into tonight. ...20Z Update... No changes have been made to the Marginal Risk across parts of southern New England. Strong to locally damaging thunderstorm winds and perhaps a brief tornado remain possible, mainly in the 00-06Z (8 PM - 2 AM EDT) time frame. ..Gleason.. 10/16/2019 .PREV DISCUSSION... /ISSUED 1108 AM CDT Wed Oct 16 2019/ ...Mid Atlantic Region... This morning's water vapor loop shows a vigorous shortwave trough tracking rapidly eastward across the northern Appalachians. The strong surface cold front associated with this trough is moving across WV and western PA, and will move into the Mid Atlantic region this afternoon. Fast-moving showers with gusty winds will be possible. Very isolated lightning strikes may occur with this activity through the afternoon, but current indications are that lightning coverage will remain below 10%. ...Southern New England... By late afternoon, the cold front will surge off the Mid Atlantic coast and begin affecting New England. Rapid cyclogenesis will be occurring off the NJ/Long Island coast during the evening, resulting in very strong low-level warm advection and impressive vertical shear profiles. Several 12z CAM solutions indicate some convective organization over parts of Long Island, CT, RI, and southeast MA. Forecast soundings suggest a window of opportunity for surface-based convection and perhaps a damaging wind gust or brief tornado in the 00-06z period this evening. Read more View SPC Outlook
  2. SPC 2000Z Day 1 Outlook Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0256 PM CDT Wed Oct 16 2019 Valid 162000Z - 171200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTHERN NEW ENGLAND... ...SUMMARY... Locally gusty/damaging thunderstorm winds may occur over southern New England this evening into tonight. ...20Z Update... No changes have been made to the Marginal Risk across parts of southern New England. Strong to locally damaging thunderstorm winds and perhaps a brief tornado remain possible, mainly in the 00-06Z (8 PM - 2 AM EDT) time frame. ..Gleason.. 10/16/2019 .PREV DISCUSSION... /ISSUED 1108 AM CDT Wed Oct 16 2019/ ...Mid Atlantic Region... This morning's water vapor loop shows a vigorous shortwave trough tracking rapidly eastward across the northern Appalachians. The strong surface cold front associated with this trough is moving across WV and western PA, and will move into the Mid Atlantic region this afternoon. Fast-moving showers with gusty winds will be possible. Very isolated lightning strikes may occur with this activity through the afternoon, but current indications are that lightning coverage will remain below 10%. ...Southern New England... By late afternoon, the cold front will surge off the Mid Atlantic coast and begin affecting New England. Rapid cyclogenesis will be occurring off the NJ/Long Island coast during the evening, resulting in very strong low-level warm advection and impressive vertical shear profiles. Several 12z CAM solutions indicate some convective organization over parts of Long Island, CT, RI, and southeast MA. Forecast soundings suggest a window of opportunity for surface-based convection and perhaps a damaging wind gust or brief tornado in the 00-06z period this evening. Read more View SPC Outlook
  3. SPC Day 2 Fire Weather Outlook Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0226 PM CDT Wed Oct 16 2019 Valid 171200Z - 181200Z ...CRITICAL FIRE WEATHER AREA FOR NORTHWEST COLORADO INTO SOUTH-CENTRAL WYOMING... The elevated areas were combined as elevated conditions are likely to develop across the Colorado Rockies with valleys/lower elevations of the high country favored. Additionally, elevated conditions (southerly sustained winds of 15-20 mph and RH values of 10-20%) are expected across more the central High Plains than previously forecast. Elevated conditions may develop across portions of southern Nevada and southwest Utah ahead of the approaching cold front, but there is too much uncertainty regarding duration and overlapping of elevated winds/RH to include an area at this time. ..Nauslar.. 10/16/2019 .PREV DISCUSSION... /ISSUED 0209 AM CDT Wed Oct 16 2019/ ...Synopsis... A large-scale trough across the Intermountain region will increase mid-level flow across a broad area from the southern to central Rockies and surrounding areas. A deepening surface cyclone in the northern Plains will also foster increased southerly/westerly flow across much of the High Plains. ...Northwestern Colorado into central/eastern Wyoming... A favorably timed mid-level wind maximum will impact the region during the afternoon. Efficient boundary-layer mixing depicted in forecast soundings will bring strong mid-level flow to the surface. To the east, a surface trough in the adjacent High Plains will further increase surface flow. Winds of 15-25 mph, with higher gusts, are expected. The corridor of strongest winds is forecast to impact far northwestern Colorado into parts of the Great Divide Basin. A critical area has been included for portions of these areas where enough dry fuel mass exists to support large fires. Elevated conditions are expected elsewhere due to a combination of lighter winds and higher RH. ...Portions of southeastern Colorado...Northeastern New Mexico...Adjacent areas of KS/OK/TX... A mid-level jet is also expected to impact this region during the afternoon. As the case farther north/west, lee troughing will further contribute to enhancing surface southwesterly downslope flow. Wind speeds will generally be 15-20 mph with RH likely in the 10-20% range. A corridor of stronger winds (potentially 20-25 mph) may develop in northeastern New Mexico into far northwest TX Panhandle and OK Panhandle. However, fuel receptiveness is too low to warrant the introduction of a critical area. ...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 0226 PM CDT Wed Oct 16 2019 Valid 171200Z - 181200Z ...CRITICAL FIRE WEATHER AREA FOR NORTHWEST COLORADO INTO SOUTH-CENTRAL WYOMING... The elevated areas were combined as elevated conditions are likely to develop across the Colorado Rockies with valleys/lower elevations of the high country favored. Additionally, elevated conditions (southerly sustained winds of 15-20 mph and RH values of 10-20%) are expected across more the central High Plains than previously forecast. Elevated conditions may develop across portions of southern Nevada and southwest Utah ahead of the approaching cold front, but there is too much uncertainty regarding duration and overlapping of elevated winds/RH to include an area at this time. ..Nauslar.. 10/16/2019 .PREV DISCUSSION... /ISSUED 0209 AM CDT Wed Oct 16 2019/ ...Synopsis... A large-scale trough across the Intermountain region will increase mid-level flow across a broad area from the southern to central Rockies and surrounding areas. A deepening surface cyclone in the northern Plains will also foster increased southerly/westerly flow across much of the High Plains. ...Northwestern Colorado into central/eastern Wyoming... A favorably timed mid-level wind maximum will impact the region during the afternoon. Efficient boundary-layer mixing depicted in forecast soundings will bring strong mid-level flow to the surface. To the east, a surface trough in the adjacent High Plains will further increase surface flow. Winds of 15-25 mph, with higher gusts, are expected. The corridor of strongest winds is forecast to impact far northwestern Colorado into parts of the Great Divide Basin. A critical area has been included for portions of these areas where enough dry fuel mass exists to support large fires. Elevated conditions are expected elsewhere due to a combination of lighter winds and higher RH. ...Portions of southeastern Colorado...Northeastern New Mexico...Adjacent areas of KS/OK/TX... A mid-level jet is also expected to impact this region during the afternoon. As the case farther north/west, lee troughing will further contribute to enhancing surface southwesterly downslope flow. Wind speeds will generally be 15-20 mph with RH likely in the 10-20% range. A corridor of stronger winds (potentially 20-25 mph) may develop in northeastern New Mexico into far northwest TX Panhandle and OK Panhandle. However, fuel receptiveness is too low to warrant the introduction of a critical area. ...Please see www.spc.noaa.gov/fire for graphic product... Read more View the full article
  5. SPC 1730Z Day 2 Outlook Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1218 PM CDT Wed Oct 16 2019 Valid 171200Z - 181200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms appear unlikely across the contiguous United States on Thursday. ...Synopsis and Discussion... A large-scale upper trough/low and associated surface low/Nor'easter will develop slowly northeastward across New England on Thursday. A related cold front is forecast to stall over the central FL Peninsula Thursday afternoon. Weak low-level convergence along the front will probably limit overall storm coverage through much of the day, although some guidance indicates potential for isolated convective development with a weak sea breeze along/near the east coast of the FL Peninsula by late afternoon. Modestly enhanced mid-level flow will be present across this region along with weak to moderate instability, but poor mid-level lapse rates should generally limit the threat for organized severe storms. Farther west, isolated storms may develop Thursday afternoon/evening from the Four Corners region into parts of the central Rockies as cooling mid-level temperatures and ascent preceding an upper trough overspread these areas. Isolated, low-topped convection will also be possible in a post-frontal regime across mainly coastal portions of the Pacific Northwest. Weak instability across all these regions is expected to preclude any meaningful severe threat. ...MAXIMUM RISK BY HAZARD... Tornado: <2% - None Wind: <5% - None Hail: <5% - None ..Gleason.. 10/16/2019 Read more View SPC Outlook
  6. SPC 1730Z Day 2 Outlook Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1218 PM CDT Wed Oct 16 2019 Valid 171200Z - 181200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms appear unlikely across the contiguous United States on Thursday. ...Synopsis and Discussion... A large-scale upper trough/low and associated surface low/Nor'easter will develop slowly northeastward across New England on Thursday. A related cold front is forecast to stall over the central FL Peninsula Thursday afternoon. Weak low-level convergence along the front will probably limit overall storm coverage through much of the day, although some guidance indicates potential for isolated convective development with a weak sea breeze along/near the east coast of the FL Peninsula by late afternoon. Modestly enhanced mid-level flow will be present across this region along with weak to moderate instability, but poor mid-level lapse rates should generally limit the threat for organized severe storms. Farther west, isolated storms may develop Thursday afternoon/evening from the Four Corners region into parts of the central Rockies as cooling mid-level temperatures and ascent preceding an upper trough overspread these areas. Isolated, low-topped convection will also be possible in a post-frontal regime across mainly coastal portions of the Pacific Northwest. Weak instability across all these regions is expected to preclude any meaningful severe threat. ...MAXIMUM RISK BY HAZARD... Tornado: <2% - None Wind: <5% - None Hail: <5% - None ..Gleason.. 10/16/2019 Read more View SPC Outlook
  7. SPC 1730Z Day 2 Outlook Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1218 PM CDT Wed Oct 16 2019 Valid 171200Z - 181200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms appear unlikely across the contiguous United States on Thursday. ...Synopsis and Discussion... A large-scale upper trough/low and associated surface low/Nor'easter will develop slowly northeastward across New England on Thursday. A related cold front is forecast to stall over the central FL Peninsula Thursday afternoon. Weak low-level convergence along the front will probably limit overall storm coverage through much of the day, although some guidance indicates potential for isolated convective development with a weak sea breeze along/near the east coast of the FL Peninsula by late afternoon. Modestly enhanced mid-level flow will be present across this region along with weak to moderate instability, but poor mid-level lapse rates should generally limit the threat for organized severe storms. Farther west, isolated storms may develop Thursday afternoon/evening from the Four Corners region into parts of the central Rockies as cooling mid-level temperatures and ascent preceding an upper trough overspread these areas. Isolated, low-topped convection will also be possible in a post-frontal regime across mainly coastal portions of the Pacific Northwest. Weak instability across all these regions is expected to preclude any meaningful severe threat. ...MAXIMUM RISK BY HAZARD... Tornado: <2% - None Wind: <5% - None Hail: <5% - None ..Gleason.. 10/16/2019 Read more View SPC Outlook
  8. SPC 1730Z Day 2 Outlook Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1218 PM CDT Wed Oct 16 2019 Valid 171200Z - 181200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms appear unlikely across the contiguous United States on Thursday. ...Synopsis and Discussion... A large-scale upper trough/low and associated surface low/Nor'easter will develop slowly northeastward across New England on Thursday. A related cold front is forecast to stall over the central FL Peninsula Thursday afternoon. Weak low-level convergence along the front will probably limit overall storm coverage through much of the day, although some guidance indicates potential for isolated convective development with a weak sea breeze along/near the east coast of the FL Peninsula by late afternoon. Modestly enhanced mid-level flow will be present across this region along with weak to moderate instability, but poor mid-level lapse rates should generally limit the threat for organized severe storms. Farther west, isolated storms may develop Thursday afternoon/evening from the Four Corners region into parts of the central Rockies as cooling mid-level temperatures and ascent preceding an upper trough overspread these areas. Isolated, low-topped convection will also be possible in a post-frontal regime across mainly coastal portions of the Pacific Northwest. Weak instability across all these regions is expected to preclude any meaningful severe threat. ...MAXIMUM RISK BY HAZARD... Tornado: <2% - None Wind: <5% - None Hail: <5% - None ..Gleason.. 10/16/2019 Read more View SPC Outlook
  9. SPC 1630Z Day 1 Outlook Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1108 AM CDT Wed Oct 16 2019 Valid 161630Z - 171200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF SOUTHERN NEW ENGLAND THIS EVENING... ...SUMMARY... Locally gusty/damaging winds may occur over southern New England this evening. ...Mid Atlantic Region... This morning's water vapor loop shows a vigorous shortwave trough tracking rapidly eastward across the northern Appalachians. The strong surface cold front associated with this trough is moving across WV and western PA, and will move into the Mid Atlantic region this afternoon. Fast-moving showers with gusty winds will be possible. Very isolated lightning strikes may occur with this activity through the afternoon, but current indications are that lightning coverage will remain below 10%. ...Southern New England... By late afternoon, the cold front will surge off the Mid Atlantic coast and begin affecting New England. Rapid cyclogenesis will be occurring off the NJ/Long Island coast during the evening, resulting in very strong low-level warm advection and impressive vertical shear profiles. Several 12z CAM solutions indicate some convective organization over parts of Long Island, CT, RI, and southeast MA. Forecast soundings suggest a window of opportunity for surface-based convection and perhaps a damaging wind gust or brief tornado in the 00-06z period this evening. ..Hart/Cook.. 10/16/2019 Read more View SPC Outlook
  10. SPC 1630Z Day 1 Outlook Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1108 AM CDT Wed Oct 16 2019 Valid 161630Z - 171200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF SOUTHERN NEW ENGLAND THIS EVENING... ...SUMMARY... Locally gusty/damaging winds may occur over southern New England this evening. ...Mid Atlantic Region... This morning's water vapor loop shows a vigorous shortwave trough tracking rapidly eastward across the northern Appalachians. The strong surface cold front associated with this trough is moving across WV and western PA, and will move into the Mid Atlantic region this afternoon. Fast-moving showers with gusty winds will be possible. Very isolated lightning strikes may occur with this activity through the afternoon, but current indications are that lightning coverage will remain below 10%. ...Southern New England... By late afternoon, the cold front will surge off the Mid Atlantic coast and begin affecting New England. Rapid cyclogenesis will be occurring off the NJ/Long Island coast during the evening, resulting in very strong low-level warm advection and impressive vertical shear profiles. Several 12z CAM solutions indicate some convective organization over parts of Long Island, CT, RI, and southeast MA. Forecast soundings suggest a window of opportunity for surface-based convection and perhaps a damaging wind gust or brief tornado in the 00-06z period this evening. ..Hart/Cook.. 10/16/2019 Read more View SPC Outlook
  11. SPC 1630Z Day 1 Outlook Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1108 AM CDT Wed Oct 16 2019 Valid 161630Z - 171200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF SOUTHERN NEW ENGLAND THIS EVENING... ...SUMMARY... Locally gusty/damaging winds may occur over southern New England this evening. ...Mid Atlantic Region... This morning's water vapor loop shows a vigorous shortwave trough tracking rapidly eastward across the northern Appalachians. The strong surface cold front associated with this trough is moving across WV and western PA, and will move into the Mid Atlantic region this afternoon. Fast-moving showers with gusty winds will be possible. Very isolated lightning strikes may occur with this activity through the afternoon, but current indications are that lightning coverage will remain below 10%. ...Southern New England... By late afternoon, the cold front will surge off the Mid Atlantic coast and begin affecting New England. Rapid cyclogenesis will be occurring off the NJ/Long Island coast during the evening, resulting in very strong low-level warm advection and impressive vertical shear profiles. Several 12z CAM solutions indicate some convective organization over parts of Long Island, CT, RI, and southeast MA. Forecast soundings suggest a window of opportunity for surface-based convection and perhaps a damaging wind gust or brief tornado in the 00-06z period this evening. ..Hart/Cook.. 10/16/2019 Read more View SPC Outlook
  12. SPC 1630Z Day 1 Outlook Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1108 AM CDT Wed Oct 16 2019 Valid 161630Z - 171200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF SOUTHERN NEW ENGLAND THIS EVENING... ...SUMMARY... Locally gusty/damaging winds may occur over southern New England this evening. ...Mid Atlantic Region... This morning's water vapor loop shows a vigorous shortwave trough tracking rapidly eastward across the northern Appalachians. The strong surface cold front associated with this trough is moving across WV and western PA, and will move into the Mid Atlantic region this afternoon. Fast-moving showers with gusty winds will be possible. Very isolated lightning strikes may occur with this activity through the afternoon, but current indications are that lightning coverage will remain below 10%. ...Southern New England... By late afternoon, the cold front will surge off the Mid Atlantic coast and begin affecting New England. Rapid cyclogenesis will be occurring off the NJ/Long Island coast during the evening, resulting in very strong low-level warm advection and impressive vertical shear profiles. Several 12z CAM solutions indicate some convective organization over parts of Long Island, CT, RI, and southeast MA. Forecast soundings suggest a window of opportunity for surface-based convection and perhaps a damaging wind gust or brief tornado in the 00-06z period this evening. ..Hart/Cook.. 10/16/2019 Read more View SPC Outlook
  13. SPC Day 1 Fire Weather Outlook Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1037 AM CDT Wed Oct 16 2019 Valid 161700Z - 171200Z The forecast remains on track, and no changes are necessary. Please see the discussion below for more details. ..Nauslar.. 10/16/2019 .PREV DISCUSSION... /ISSUED 0211 AM CDT Wed Oct 16 2019/ ...Synopsis... An upper-level ridge will shift from over the Great Basin to across the Continental Divide. Farther west, an upper-level trough will into the western Great Basin by the end of the period. At the surface, high pressure will remain across the Gulf Coast into the lower/mid-Mississippi Valley. With the approach of the upper-level trough, a surface cyclone will deepen in the Canadian Prairie with a pendant surface trough extending into the central High Plains. ...Southeastern Oregon and far northwest Nevada... Ahead of an approaching Pacific cold front, surface southwesterly flow will increase to 15-20 mph and RH during the afternoon will fall to 10-20%. Dry fine fuels will support potential for fire spread. Some guidance depicts locally critical conditions are possible, but unfavorable 100/1000-hour fuels should limit large fire potential across the area. ...Southern Wyoming into northwestern Colorado... The combination of the surface trough to the east as well as modest boundary-layer mixing of mid-level flow will lead to elevated fire weather concerns across this region. The strongest wind speeds (15-25 mph) will occur in Wyoming. While critical conditions are possible, the duration of 20+ mph overlapping with 15% is enough in question that no critical area will be added. Fuels in Colorado are more receptive, but weaker surface winds (15-20 mph) will similarly limit critical potential. ...Central Nevada... Dry fine fuels will support locally elevated conditions as winds increase to 15-20 mph and RH falls to 10-20% during the afternoon. No categorical highlights will be introduced as the overall large fire potential will be mitigated by unfavorable heavier-fuel moisture. ...Please see www.spc.noaa.gov/fire for graphic product... Read more View the full article
  14. SPC Day 1 Fire Weather Outlook Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1037 AM CDT Wed Oct 16 2019 Valid 161700Z - 171200Z The forecast remains on track, and no changes are necessary. Please see the discussion below for more details. ..Nauslar.. 10/16/2019 .PREV DISCUSSION... /ISSUED 0211 AM CDT Wed Oct 16 2019/ ...Synopsis... An upper-level ridge will shift from over the Great Basin to across the Continental Divide. Farther west, an upper-level trough will into the western Great Basin by the end of the period. At the surface, high pressure will remain across the Gulf Coast into the lower/mid-Mississippi Valley. With the approach of the upper-level trough, a surface cyclone will deepen in the Canadian Prairie with a pendant surface trough extending into the central High Plains. ...Southeastern Oregon and far northwest Nevada... Ahead of an approaching Pacific cold front, surface southwesterly flow will increase to 15-20 mph and RH during the afternoon will fall to 10-20%. Dry fine fuels will support potential for fire spread. Some guidance depicts locally critical conditions are possible, but unfavorable 100/1000-hour fuels should limit large fire potential across the area. ...Southern Wyoming into northwestern Colorado... The combination of the surface trough to the east as well as modest boundary-layer mixing of mid-level flow will lead to elevated fire weather concerns across this region. The strongest wind speeds (15-25 mph) will occur in Wyoming. While critical conditions are possible, the duration of 20+ mph overlapping with 15% is enough in question that no critical area will be added. Fuels in Colorado are more receptive, but weaker surface winds (15-20 mph) will similarly limit critical potential. ...Central Nevada... Dry fine fuels will support locally elevated conditions as winds increase to 15-20 mph and RH falls to 10-20% during the afternoon. No categorical highlights will be introduced as the overall large fire potential will be mitigated by unfavorable heavier-fuel moisture. ...Please see www.spc.noaa.gov/fire for graphic product... Read more View the full article
  15. SPC 1300Z Day 1 Outlook Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0746 AM CDT Wed Oct 16 2019 Valid 161300Z - 171200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe-thunderstorm potential appears minimal over the U.S. today and tonight. ...Synopsis... In mid/upper levels, a progressive synoptic pattern will exist this period, featuring eastern troughing, ridging over the rockies, and height falls across the Pacific Coast. The latter will be related to a strong trough -- now apparent in moisture-channel imagery over the northeastern Pacific between 135W-140W. Once the trough moves inland this evening, associated cooling in midlevels will steepen lapse rates above a marine air mass, leading to buoyancy of marginal magnitude and depth for isolated lightning production from associated convection moving ashore. Downstream, a well-defined mid/upper cyclone is evident over the upper Great Lakes, with trough south-southwestward across the Mid-South region. The cyclone should shift eastward to New England and deepen by 12Z, while the trough pivots across the southern Appalachians, then offshore from the Mid-Atlantic region. A southern-stream perturbation -- initially located between AMA-LBB -- should move slowly southward and become a small, closed cyclone, increasingly cut off from the prevailing westerlies by the eastward-moving synoptic ridge. At the surface, 11Z analysis showed a deeply occluded low, corresponding to the mid/upper cyclone, over northern Lake Huron. The occluded front arched eastward then southward across the central Appalachians, becoming a cold front over the southern Appalachians to central MS, central LA and south-central TX. A diffuse warm front extended east-northeast/west-southwest across eastern NC and central SC, amidst a large area of precip. A weak low -- initially drawn along the warm front near CAE -- will deepen gradually through the day and move northeastward across the Delmarva Peninsula region, while being overtaken by the cold front. By 00Z, the low should be near coastal NJ, with cold front just offshore from the Carolinas and across parts of southern GA and the FL Panhandle. ...Coastal NC... A low-CAPE/strong-shear parameter space, marginally favorable for supercells, may brush the immediate coastal areas from ILM northeastward across the southern Outer Banks and past HSE through early/mid afternoon. Northward/inland extent of favorable destabilization is uncertain, given extensive precip evident over the region and even offshore. As the surface low deepens to the north, a few hours of relatively backed surface winds and higher theta-e are possible over the sounds/banks amidst suitable isallobaric forcing. However, the most favorably buoyant air, and the great majority of surface-based deep convection, will remain offshore. Weak deep-layer lapse rates will prevail, supporting only around 500-700 J/kg MLCAPE over the beaches, increasing with southward/offshore extent across the Gulf Stream. For now, the severe potential appears too conditional, isolated, and limited in coverage to warrant an unconditional outlook area. ..Edwards/Goss.. 10/16/2019 Read more View SPC Outlook
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