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SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1138 AM CDT Mon Sep 16 2024 Valid 161700Z - 171200Z ...17z Update... The prior forecast remains largely on track with only minor changes. The Elevated area over parts of NV was expanded northward where gusty winds and pockets of low humidity are expected to be slightly more prevalent. Over the central High Plains, recent rainfall and additional storms are likely to temper fuels somewhat. However, strong southerly winds (gusts as high as 30 mph) may still overlap with areas of drier fuels and humidity below 30%. While uncertain in areal extent, some fire-weather risk will continue this afternoon and evening. Otherwise, see the prior discussion for more information. ..Lyons.. 09/16/2024 .PREV DISCUSSION... /ISSUED 0156 AM CDT Mon Sep 16 2024/ ...Synopsis... Within the base of a deep midlevel cyclone moving eastward across the Great Basin, a related jet streak will overspread the Lower CO River Valley. Here, boundary-layer mixing into the strengthening flow aloft, coupled with a tightening pressure gradient peripheral to an evolving surface cyclone, will favor 20-25 mph sustained southerly surface winds. Despite a gradual increase in moisture/RH, diurnal heating should still support a corridor of around 20 percent RH amid the strong surface winds along the Lower CO River Valley -- favoring elevated fire-weather conditions. Elevated fire-weather conditions are also expected over portions of the central High Plains -- where breezy/gusty southerly surface winds will overlap 20 percent RH near a lee trough during the afternoon. While spotty rainfall during the past 24 hours could limit fuel receptiveness over parts of the area, mostly receptive fuels should still yield some fire-weather risk. Farther east, warm/dry conditions are expected over portions of OH and KY -- along the southwestern periphery of an expansive surface anticyclone. While sustained surface winds around 10 mph should limit the overall fire-weather threat, around 20 percent RH and very dry/receptive fuels will still pose localized fire-weather concerns during the afternoon. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1138 AM CDT Mon Sep 16 2024 Valid 161700Z - 171200Z ...17z Update... The prior forecast remains largely on track with only minor changes. The Elevated area over parts of NV was expanded northward where gusty winds and pockets of low humidity are expected to be slightly more prevalent. Over the central High Plains, recent rainfall and additional storms are likely to temper fuels somewhat. However, strong southerly winds (gusts as high as 30 mph) may still overlap with areas of drier fuels and humidity below 30%. While uncertain in areal extent, some fire-weather risk will continue this afternoon and evening. Otherwise, see the prior discussion for more information. ..Lyons.. 09/16/2024 .PREV DISCUSSION... /ISSUED 0156 AM CDT Mon Sep 16 2024/ ...Synopsis... Within the base of a deep midlevel cyclone moving eastward across the Great Basin, a related jet streak will overspread the Lower CO River Valley. Here, boundary-layer mixing into the strengthening flow aloft, coupled with a tightening pressure gradient peripheral to an evolving surface cyclone, will favor 20-25 mph sustained southerly surface winds. Despite a gradual increase in moisture/RH, diurnal heating should still support a corridor of around 20 percent RH amid the strong surface winds along the Lower CO River Valley -- favoring elevated fire-weather conditions. Elevated fire-weather conditions are also expected over portions of the central High Plains -- where breezy/gusty southerly surface winds will overlap 20 percent RH near a lee trough during the afternoon. While spotty rainfall during the past 24 hours could limit fuel receptiveness over parts of the area, mostly receptive fuels should still yield some fire-weather risk. Farther east, warm/dry conditions are expected over portions of OH and KY -- along the southwestern periphery of an expansive surface anticyclone. While sustained surface winds around 10 mph should limit the overall fire-weather threat, around 20 percent RH and very dry/receptive fuels will still pose localized fire-weather concerns during the afternoon. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1138 AM CDT Mon Sep 16 2024 Valid 161700Z - 171200Z ...17z Update... The prior forecast remains largely on track with only minor changes. The Elevated area over parts of NV was expanded northward where gusty winds and pockets of low humidity are expected to be slightly more prevalent. Over the central High Plains, recent rainfall and additional storms are likely to temper fuels somewhat. However, strong southerly winds (gusts as high as 30 mph) may still overlap with areas of drier fuels and humidity below 30%. While uncertain in areal extent, some fire-weather risk will continue this afternoon and evening. Otherwise, see the prior discussion for more information. ..Lyons.. 09/16/2024 .PREV DISCUSSION... /ISSUED 0156 AM CDT Mon Sep 16 2024/ ...Synopsis... Within the base of a deep midlevel cyclone moving eastward across the Great Basin, a related jet streak will overspread the Lower CO River Valley. Here, boundary-layer mixing into the strengthening flow aloft, coupled with a tightening pressure gradient peripheral to an evolving surface cyclone, will favor 20-25 mph sustained southerly surface winds. Despite a gradual increase in moisture/RH, diurnal heating should still support a corridor of around 20 percent RH amid the strong surface winds along the Lower CO River Valley -- favoring elevated fire-weather conditions. Elevated fire-weather conditions are also expected over portions of the central High Plains -- where breezy/gusty southerly surface winds will overlap 20 percent RH near a lee trough during the afternoon. While spotty rainfall during the past 24 hours could limit fuel receptiveness over parts of the area, mostly receptive fuels should still yield some fire-weather risk. Farther east, warm/dry conditions are expected over portions of OH and KY -- along the southwestern periphery of an expansive surface anticyclone. While sustained surface winds around 10 mph should limit the overall fire-weather threat, around 20 percent RH and very dry/receptive fuels will still pose localized fire-weather concerns during the afternoon. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Mon Sep 16 2024 Valid 161630Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF NORTH DAKOTA INTO NORTHWEST MINNESOTA...AND EASTERN NORTH CAROLINA... ...SUMMARY... The threat for a few tornadoes will continue this afternoon and evening over eastern North Carolina and vicinity. Thunderstorms capable of producing severe gusts and large hail should occur today in parts of the northern Plains. Isolated severe wind and hail also appears possible across parts of the Great Basin to Four Corners. ...North Dakota into Northwest Minnesota... Elevated thunderstorms which have produced sporadic, marginally severe hail earlier this morning across parts of ND into northwest MN have generally remained sub-severe over the past couple of hours as a southerly low-level jet has gradually weakened. In the wake of this activity, a surface low should consolidate over the northern High Plains, with a front and convectively reinforced outflow expected to lift slowly northward across ND this afternoon/evening as an effective warm front. Airmass recovery is expected along/south of this boundary, with steepening mid-level lapse rates, moistening at low-levels, and daytime heating all contributing to moderate instability by later this afternoon. While low/mid-level flow will not be overly strong for most of the day, strengthening low-level southerly flow is expected again this evening as a low-level jet strengthens across the northern/central Plains. Current expectations are for robust thunderstorms to develop along/near the front late this afternoon and early evening. Enough deep-layer shear should be present to support a threat of large hail with any supercells initially. With time, some clustering should occur. A potentially greater wind threat may exist through the evening as activity spreads east-northeastward across central/eastern ND into northwest MN. A tornado or two also appears possible with any surface-based convection along/south of the front, especially this evening as 0-1 km shear increases with the strengthening low-level jet. ...Eastern North Carolina and Vicinity... The surface low off the NC/SC Coast (Potential Tropical Cyclone 8) is forecast by NHC to move northwest and inland across parts of SC through this evening. A surface trough/weak baroclinic zone extends northeastward from the low just off the NC Coast/Outer Banks. As the system moves inland, enhanced low-level flow should turn more east-southeasterly. Various NAM/RAP forecast soundings suggest that as low 70s surface dewpoints advance inland along the coastal plain of eastern NC, then only modest/filtered daytime heating will be needed to support weak boundary-layer destabilization. Sufficiently enlarged low-level hodographs should support a threat for a few tornadoes with any low-topped supercells that can form offshore and be sustained inland across coastal portions of eastern NC. The Slight Risk for this region has been maintained with only small adjustments based on recent observations and 12Z guidance. ...Great Basin into the Four Corners... A deep, closed upper low centered over CA this morning will advance slowly eastward across parts of the Great Basin through the period. An attendant south-southwesterly mid-level jet will overspread eastern portions of the Great Basin into the Four Corners region this afternoon and evening. Although cloud cover remains prevalent across parts of these areas, some daytime heating will encourage the development of weak instability by mid to late afternoon. Stronger mid-level flow and related deep-layer shear are forecast across the Four Corners vicinity, where marginal supercell structures could pose an isolated hail threat. Even though instability should generally remain weak owing to limited low-level moisture, occasional strong to severe wind gusts should be the main threat with various small clusters that can form/consolidate and subsequently spread north-northeastward through the early evening. This wind threat will be locally maximized where filtered diurnal heating can help steepen low-level lapse rates. ...Central High Plains... Relatively high-based thunderstorms may develop this afternoon across parts of the central High Plains, generally along/east of a weak surface trough. This region will be mostly displaced to the east of large-scale ascent associated with the upper low over the West. Even so, a narrow zone of weak to moderate instability should be in place across parts of central NE into western KS by peak afternoon heating. Although flow through low/mid levels should remain modest for much of the afternoon, a veering wind profile with height should foster around 25-35 kt of deep-layer shear, sufficient for some updraft organization. The primary uncertainty regarding any isolated severe hail/wind threat remains whether convection will initiate or not. Have therefore not added a Marginal Risk across parts of the central High Plains with this update, but trends will continue to be monitored. ..Gleason/Supinie.. 09/16/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Mon Sep 16 2024 Valid 161630Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF NORTH DAKOTA INTO NORTHWEST MINNESOTA...AND EASTERN NORTH CAROLINA... ...SUMMARY... The threat for a few tornadoes will continue this afternoon and evening over eastern North Carolina and vicinity. Thunderstorms capable of producing severe gusts and large hail should occur today in parts of the northern Plains. Isolated severe wind and hail also appears possible across parts of the Great Basin to Four Corners. ...North Dakota into Northwest Minnesota... Elevated thunderstorms which have produced sporadic, marginally severe hail earlier this morning across parts of ND into northwest MN have generally remained sub-severe over the past couple of hours as a southerly low-level jet has gradually weakened. In the wake of this activity, a surface low should consolidate over the northern High Plains, with a front and convectively reinforced outflow expected to lift slowly northward across ND this afternoon/evening as an effective warm front. Airmass recovery is expected along/south of this boundary, with steepening mid-level lapse rates, moistening at low-levels, and daytime heating all contributing to moderate instability by later this afternoon. While low/mid-level flow will not be overly strong for most of the day, strengthening low-level southerly flow is expected again this evening as a low-level jet strengthens across the northern/central Plains. Current expectations are for robust thunderstorms to develop along/near the front late this afternoon and early evening. Enough deep-layer shear should be present to support a threat of large hail with any supercells initially. With time, some clustering should occur. A potentially greater wind threat may exist through the evening as activity spreads east-northeastward across central/eastern ND into northwest MN. A tornado or two also appears possible with any surface-based convection along/south of the front, especially this evening as 0-1 km shear increases with the strengthening low-level jet. ...Eastern North Carolina and Vicinity... The surface low off the NC/SC Coast (Potential Tropical Cyclone 8) is forecast by NHC to move northwest and inland across parts of SC through this evening. A surface trough/weak baroclinic zone extends northeastward from the low just off the NC Coast/Outer Banks. As the system moves inland, enhanced low-level flow should turn more east-southeasterly. Various NAM/RAP forecast soundings suggest that as low 70s surface dewpoints advance inland along the coastal plain of eastern NC, then only modest/filtered daytime heating will be needed to support weak boundary-layer destabilization. Sufficiently enlarged low-level hodographs should support a threat for a few tornadoes with any low-topped supercells that can form offshore and be sustained inland across coastal portions of eastern NC. The Slight Risk for this region has been maintained with only small adjustments based on recent observations and 12Z guidance. ...Great Basin into the Four Corners... A deep, closed upper low centered over CA this morning will advance slowly eastward across parts of the Great Basin through the period. An attendant south-southwesterly mid-level jet will overspread eastern portions of the Great Basin into the Four Corners region this afternoon and evening. Although cloud cover remains prevalent across parts of these areas, some daytime heating will encourage the development of weak instability by mid to late afternoon. Stronger mid-level flow and related deep-layer shear are forecast across the Four Corners vicinity, where marginal supercell structures could pose an isolated hail threat. Even though instability should generally remain weak owing to limited low-level moisture, occasional strong to severe wind gusts should be the main threat with various small clusters that can form/consolidate and subsequently spread north-northeastward through the early evening. This wind threat will be locally maximized where filtered diurnal heating can help steepen low-level lapse rates. ...Central High Plains... Relatively high-based thunderstorms may develop this afternoon across parts of the central High Plains, generally along/east of a weak surface trough. This region will be mostly displaced to the east of large-scale ascent associated with the upper low over the West. Even so, a narrow zone of weak to moderate instability should be in place across parts of central NE into western KS by peak afternoon heating. Although flow through low/mid levels should remain modest for much of the afternoon, a veering wind profile with height should foster around 25-35 kt of deep-layer shear, sufficient for some updraft organization. The primary uncertainty regarding any isolated severe hail/wind threat remains whether convection will initiate or not. Have therefore not added a Marginal Risk across parts of the central High Plains with this update, but trends will continue to be monitored. ..Gleason/Supinie.. 09/16/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Mon Sep 16 2024 Valid 161630Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF NORTH DAKOTA INTO NORTHWEST MINNESOTA...AND EASTERN NORTH CAROLINA... ...SUMMARY... The threat for a few tornadoes will continue this afternoon and evening over eastern North Carolina and vicinity. Thunderstorms capable of producing severe gusts and large hail should occur today in parts of the northern Plains. Isolated severe wind and hail also appears possible across parts of the Great Basin to Four Corners. ...North Dakota into Northwest Minnesota... Elevated thunderstorms which have produced sporadic, marginally severe hail earlier this morning across parts of ND into northwest MN have generally remained sub-severe over the past couple of hours as a southerly low-level jet has gradually weakened. In the wake of this activity, a surface low should consolidate over the northern High Plains, with a front and convectively reinforced outflow expected to lift slowly northward across ND this afternoon/evening as an effective warm front. Airmass recovery is expected along/south of this boundary, with steepening mid-level lapse rates, moistening at low-levels, and daytime heating all contributing to moderate instability by later this afternoon. While low/mid-level flow will not be overly strong for most of the day, strengthening low-level southerly flow is expected again this evening as a low-level jet strengthens across the northern/central Plains. Current expectations are for robust thunderstorms to develop along/near the front late this afternoon and early evening. Enough deep-layer shear should be present to support a threat of large hail with any supercells initially. With time, some clustering should occur. A potentially greater wind threat may exist through the evening as activity spreads east-northeastward across central/eastern ND into northwest MN. A tornado or two also appears possible with any surface-based convection along/south of the front, especially this evening as 0-1 km shear increases with the strengthening low-level jet. ...Eastern North Carolina and Vicinity... The surface low off the NC/SC Coast (Potential Tropical Cyclone 8) is forecast by NHC to move northwest and inland across parts of SC through this evening. A surface trough/weak baroclinic zone extends northeastward from the low just off the NC Coast/Outer Banks. As the system moves inland, enhanced low-level flow should turn more east-southeasterly. Various NAM/RAP forecast soundings suggest that as low 70s surface dewpoints advance inland along the coastal plain of eastern NC, then only modest/filtered daytime heating will be needed to support weak boundary-layer destabilization. Sufficiently enlarged low-level hodographs should support a threat for a few tornadoes with any low-topped supercells that can form offshore and be sustained inland across coastal portions of eastern NC. The Slight Risk for this region has been maintained with only small adjustments based on recent observations and 12Z guidance. ...Great Basin into the Four Corners... A deep, closed upper low centered over CA this morning will advance slowly eastward across parts of the Great Basin through the period. An attendant south-southwesterly mid-level jet will overspread eastern portions of the Great Basin into the Four Corners region this afternoon and evening. Although cloud cover remains prevalent across parts of these areas, some daytime heating will encourage the development of weak instability by mid to late afternoon. Stronger mid-level flow and related deep-layer shear are forecast across the Four Corners vicinity, where marginal supercell structures could pose an isolated hail threat. Even though instability should generally remain weak owing to limited low-level moisture, occasional strong to severe wind gusts should be the main threat with various small clusters that can form/consolidate and subsequently spread north-northeastward through the early evening. This wind threat will be locally maximized where filtered diurnal heating can help steepen low-level lapse rates. ...Central High Plains... Relatively high-based thunderstorms may develop this afternoon across parts of the central High Plains, generally along/east of a weak surface trough. This region will be mostly displaced to the east of large-scale ascent associated with the upper low over the West. Even so, a narrow zone of weak to moderate instability should be in place across parts of central NE into western KS by peak afternoon heating. Although flow through low/mid levels should remain modest for much of the afternoon, a veering wind profile with height should foster around 25-35 kt of deep-layer shear, sufficient for some updraft organization. The primary uncertainty regarding any isolated severe hail/wind threat remains whether convection will initiate or not. Have therefore not added a Marginal Risk across parts of the central High Plains with this update, but trends will continue to be monitored. ..Gleason/Supinie.. 09/16/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Mon Sep 16 2024 Valid 161630Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF NORTH DAKOTA INTO NORTHWEST MINNESOTA...AND EASTERN NORTH CAROLINA... ...SUMMARY... The threat for a few tornadoes will continue this afternoon and evening over eastern North Carolina and vicinity. Thunderstorms capable of producing severe gusts and large hail should occur today in parts of the northern Plains. Isolated severe wind and hail also appears possible across parts of the Great Basin to Four Corners. ...North Dakota into Northwest Minnesota... Elevated thunderstorms which have produced sporadic, marginally severe hail earlier this morning across parts of ND into northwest MN have generally remained sub-severe over the past couple of hours as a southerly low-level jet has gradually weakened. In the wake of this activity, a surface low should consolidate over the northern High Plains, with a front and convectively reinforced outflow expected to lift slowly northward across ND this afternoon/evening as an effective warm front. Airmass recovery is expected along/south of this boundary, with steepening mid-level lapse rates, moistening at low-levels, and daytime heating all contributing to moderate instability by later this afternoon. While low/mid-level flow will not be overly strong for most of the day, strengthening low-level southerly flow is expected again this evening as a low-level jet strengthens across the northern/central Plains. Current expectations are for robust thunderstorms to develop along/near the front late this afternoon and early evening. Enough deep-layer shear should be present to support a threat of large hail with any supercells initially. With time, some clustering should occur. A potentially greater wind threat may exist through the evening as activity spreads east-northeastward across central/eastern ND into northwest MN. A tornado or two also appears possible with any surface-based convection along/south of the front, especially this evening as 0-1 km shear increases with the strengthening low-level jet. ...Eastern North Carolina and Vicinity... The surface low off the NC/SC Coast (Potential Tropical Cyclone 8) is forecast by NHC to move northwest and inland across parts of SC through this evening. A surface trough/weak baroclinic zone extends northeastward from the low just off the NC Coast/Outer Banks. As the system moves inland, enhanced low-level flow should turn more east-southeasterly. Various NAM/RAP forecast soundings suggest that as low 70s surface dewpoints advance inland along the coastal plain of eastern NC, then only modest/filtered daytime heating will be needed to support weak boundary-layer destabilization. Sufficiently enlarged low-level hodographs should support a threat for a few tornadoes with any low-topped supercells that can form offshore and be sustained inland across coastal portions of eastern NC. The Slight Risk for this region has been maintained with only small adjustments based on recent observations and 12Z guidance. ...Great Basin into the Four Corners... A deep, closed upper low centered over CA this morning will advance slowly eastward across parts of the Great Basin through the period. An attendant south-southwesterly mid-level jet will overspread eastern portions of the Great Basin into the Four Corners region this afternoon and evening. Although cloud cover remains prevalent across parts of these areas, some daytime heating will encourage the development of weak instability by mid to late afternoon. Stronger mid-level flow and related deep-layer shear are forecast across the Four Corners vicinity, where marginal supercell structures could pose an isolated hail threat. Even though instability should generally remain weak owing to limited low-level moisture, occasional strong to severe wind gusts should be the main threat with various small clusters that can form/consolidate and subsequently spread north-northeastward through the early evening. This wind threat will be locally maximized where filtered diurnal heating can help steepen low-level lapse rates. ...Central High Plains... Relatively high-based thunderstorms may develop this afternoon across parts of the central High Plains, generally along/east of a weak surface trough. This region will be mostly displaced to the east of large-scale ascent associated with the upper low over the West. Even so, a narrow zone of weak to moderate instability should be in place across parts of central NE into western KS by peak afternoon heating. Although flow through low/mid levels should remain modest for much of the afternoon, a veering wind profile with height should foster around 25-35 kt of deep-layer shear, sufficient for some updraft organization. The primary uncertainty regarding any isolated severe hail/wind threat remains whether convection will initiate or not. Have therefore not added a Marginal Risk across parts of the central High Plains with this update, but trends will continue to be monitored. ..Gleason/Supinie.. 09/16/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Mon Sep 16 2024 Valid 161630Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF NORTH DAKOTA INTO NORTHWEST MINNESOTA...AND EASTERN NORTH CAROLINA... ...SUMMARY... The threat for a few tornadoes will continue this afternoon and evening over eastern North Carolina and vicinity. Thunderstorms capable of producing severe gusts and large hail should occur today in parts of the northern Plains. Isolated severe wind and hail also appears possible across parts of the Great Basin to Four Corners. ...North Dakota into Northwest Minnesota... Elevated thunderstorms which have produced sporadic, marginally severe hail earlier this morning across parts of ND into northwest MN have generally remained sub-severe over the past couple of hours as a southerly low-level jet has gradually weakened. In the wake of this activity, a surface low should consolidate over the northern High Plains, with a front and convectively reinforced outflow expected to lift slowly northward across ND this afternoon/evening as an effective warm front. Airmass recovery is expected along/south of this boundary, with steepening mid-level lapse rates, moistening at low-levels, and daytime heating all contributing to moderate instability by later this afternoon. While low/mid-level flow will not be overly strong for most of the day, strengthening low-level southerly flow is expected again this evening as a low-level jet strengthens across the northern/central Plains. Current expectations are for robust thunderstorms to develop along/near the front late this afternoon and early evening. Enough deep-layer shear should be present to support a threat of large hail with any supercells initially. With time, some clustering should occur. A potentially greater wind threat may exist through the evening as activity spreads east-northeastward across central/eastern ND into northwest MN. A tornado or two also appears possible with any surface-based convection along/south of the front, especially this evening as 0-1 km shear increases with the strengthening low-level jet. ...Eastern North Carolina and Vicinity... The surface low off the NC/SC Coast (Potential Tropical Cyclone 8) is forecast by NHC to move northwest and inland across parts of SC through this evening. A surface trough/weak baroclinic zone extends northeastward from the low just off the NC Coast/Outer Banks. As the system moves inland, enhanced low-level flow should turn more east-southeasterly. Various NAM/RAP forecast soundings suggest that as low 70s surface dewpoints advance inland along the coastal plain of eastern NC, then only modest/filtered daytime heating will be needed to support weak boundary-layer destabilization. Sufficiently enlarged low-level hodographs should support a threat for a few tornadoes with any low-topped supercells that can form offshore and be sustained inland across coastal portions of eastern NC. The Slight Risk for this region has been maintained with only small adjustments based on recent observations and 12Z guidance. ...Great Basin into the Four Corners... A deep, closed upper low centered over CA this morning will advance slowly eastward across parts of the Great Basin through the period. An attendant south-southwesterly mid-level jet will overspread eastern portions of the Great Basin into the Four Corners region this afternoon and evening. Although cloud cover remains prevalent across parts of these areas, some daytime heating will encourage the development of weak instability by mid to late afternoon. Stronger mid-level flow and related deep-layer shear are forecast across the Four Corners vicinity, where marginal supercell structures could pose an isolated hail threat. Even though instability should generally remain weak owing to limited low-level moisture, occasional strong to severe wind gusts should be the main threat with various small clusters that can form/consolidate and subsequently spread north-northeastward through the early evening. This wind threat will be locally maximized where filtered diurnal heating can help steepen low-level lapse rates. ...Central High Plains... Relatively high-based thunderstorms may develop this afternoon across parts of the central High Plains, generally along/east of a weak surface trough. This region will be mostly displaced to the east of large-scale ascent associated with the upper low over the West. Even so, a narrow zone of weak to moderate instability should be in place across parts of central NE into western KS by peak afternoon heating. Although flow through low/mid levels should remain modest for much of the afternoon, a veering wind profile with height should foster around 25-35 kt of deep-layer shear, sufficient for some updraft organization. The primary uncertainty regarding any isolated severe hail/wind threat remains whether convection will initiate or not. Have therefore not added a Marginal Risk across parts of the central High Plains with this update, but trends will continue to be monitored. ..Gleason/Supinie.. 09/16/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Mon Sep 16 2024 Valid 161630Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF NORTH DAKOTA INTO NORTHWEST MINNESOTA...AND EASTERN NORTH CAROLINA... ...SUMMARY... The threat for a few tornadoes will continue this afternoon and evening over eastern North Carolina and vicinity. Thunderstorms capable of producing severe gusts and large hail should occur today in parts of the northern Plains. Isolated severe wind and hail also appears possible across parts of the Great Basin to Four Corners. ...North Dakota into Northwest Minnesota... Elevated thunderstorms which have produced sporadic, marginally severe hail earlier this morning across parts of ND into northwest MN have generally remained sub-severe over the past couple of hours as a southerly low-level jet has gradually weakened. In the wake of this activity, a surface low should consolidate over the northern High Plains, with a front and convectively reinforced outflow expected to lift slowly northward across ND this afternoon/evening as an effective warm front. Airmass recovery is expected along/south of this boundary, with steepening mid-level lapse rates, moistening at low-levels, and daytime heating all contributing to moderate instability by later this afternoon. While low/mid-level flow will not be overly strong for most of the day, strengthening low-level southerly flow is expected again this evening as a low-level jet strengthens across the northern/central Plains. Current expectations are for robust thunderstorms to develop along/near the front late this afternoon and early evening. Enough deep-layer shear should be present to support a threat of large hail with any supercells initially. With time, some clustering should occur. A potentially greater wind threat may exist through the evening as activity spreads east-northeastward across central/eastern ND into northwest MN. A tornado or two also appears possible with any surface-based convection along/south of the front, especially this evening as 0-1 km shear increases with the strengthening low-level jet. ...Eastern North Carolina and Vicinity... The surface low off the NC/SC Coast (Potential Tropical Cyclone 8) is forecast by NHC to move northwest and inland across parts of SC through this evening. A surface trough/weak baroclinic zone extends northeastward from the low just off the NC Coast/Outer Banks. As the system moves inland, enhanced low-level flow should turn more east-southeasterly. Various NAM/RAP forecast soundings suggest that as low 70s surface dewpoints advance inland along the coastal plain of eastern NC, then only modest/filtered daytime heating will be needed to support weak boundary-layer destabilization. Sufficiently enlarged low-level hodographs should support a threat for a few tornadoes with any low-topped supercells that can form offshore and be sustained inland across coastal portions of eastern NC. The Slight Risk for this region has been maintained with only small adjustments based on recent observations and 12Z guidance. ...Great Basin into the Four Corners... A deep, closed upper low centered over CA this morning will advance slowly eastward across parts of the Great Basin through the period. An attendant south-southwesterly mid-level jet will overspread eastern portions of the Great Basin into the Four Corners region this afternoon and evening. Although cloud cover remains prevalent across parts of these areas, some daytime heating will encourage the development of weak instability by mid to late afternoon. Stronger mid-level flow and related deep-layer shear are forecast across the Four Corners vicinity, where marginal supercell structures could pose an isolated hail threat. Even though instability should generally remain weak owing to limited low-level moisture, occasional strong to severe wind gusts should be the main threat with various small clusters that can form/consolidate and subsequently spread north-northeastward through the early evening. This wind threat will be locally maximized where filtered diurnal heating can help steepen low-level lapse rates. ...Central High Plains... Relatively high-based thunderstorms may develop this afternoon across parts of the central High Plains, generally along/east of a weak surface trough. This region will be mostly displaced to the east of large-scale ascent associated with the upper low over the West. Even so, a narrow zone of weak to moderate instability should be in place across parts of central NE into western KS by peak afternoon heating. Although flow through low/mid levels should remain modest for much of the afternoon, a veering wind profile with height should foster around 25-35 kt of deep-layer shear, sufficient for some updraft organization. The primary uncertainty regarding any isolated severe hail/wind threat remains whether convection will initiate or not. Have therefore not added a Marginal Risk across parts of the central High Plains with this update, but trends will continue to be monitored. ..Gleason/Supinie.. 09/16/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Mon Sep 16 2024 Valid 161630Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF NORTH DAKOTA INTO NORTHWEST MINNESOTA...AND EASTERN NORTH CAROLINA... ...SUMMARY... The threat for a few tornadoes will continue this afternoon and evening over eastern North Carolina and vicinity. Thunderstorms capable of producing severe gusts and large hail should occur today in parts of the northern Plains. Isolated severe wind and hail also appears possible across parts of the Great Basin to Four Corners. ...North Dakota into Northwest Minnesota... Elevated thunderstorms which have produced sporadic, marginally severe hail earlier this morning across parts of ND into northwest MN have generally remained sub-severe over the past couple of hours as a southerly low-level jet has gradually weakened. In the wake of this activity, a surface low should consolidate over the northern High Plains, with a front and convectively reinforced outflow expected to lift slowly northward across ND this afternoon/evening as an effective warm front. Airmass recovery is expected along/south of this boundary, with steepening mid-level lapse rates, moistening at low-levels, and daytime heating all contributing to moderate instability by later this afternoon. While low/mid-level flow will not be overly strong for most of the day, strengthening low-level southerly flow is expected again this evening as a low-level jet strengthens across the northern/central Plains. Current expectations are for robust thunderstorms to develop along/near the front late this afternoon and early evening. Enough deep-layer shear should be present to support a threat of large hail with any supercells initially. With time, some clustering should occur. A potentially greater wind threat may exist through the evening as activity spreads east-northeastward across central/eastern ND into northwest MN. A tornado or two also appears possible with any surface-based convection along/south of the front, especially this evening as 0-1 km shear increases with the strengthening low-level jet. ...Eastern North Carolina and Vicinity... The surface low off the NC/SC Coast (Potential Tropical Cyclone 8) is forecast by NHC to move northwest and inland across parts of SC through this evening. A surface trough/weak baroclinic zone extends northeastward from the low just off the NC Coast/Outer Banks. As the system moves inland, enhanced low-level flow should turn more east-southeasterly. Various NAM/RAP forecast soundings suggest that as low 70s surface dewpoints advance inland along the coastal plain of eastern NC, then only modest/filtered daytime heating will be needed to support weak boundary-layer destabilization. Sufficiently enlarged low-level hodographs should support a threat for a few tornadoes with any low-topped supercells that can form offshore and be sustained inland across coastal portions of eastern NC. The Slight Risk for this region has been maintained with only small adjustments based on recent observations and 12Z guidance. ...Great Basin into the Four Corners... A deep, closed upper low centered over CA this morning will advance slowly eastward across parts of the Great Basin through the period. An attendant south-southwesterly mid-level jet will overspread eastern portions of the Great Basin into the Four Corners region this afternoon and evening. Although cloud cover remains prevalent across parts of these areas, some daytime heating will encourage the development of weak instability by mid to late afternoon. Stronger mid-level flow and related deep-layer shear are forecast across the Four Corners vicinity, where marginal supercell structures could pose an isolated hail threat. Even though instability should generally remain weak owing to limited low-level moisture, occasional strong to severe wind gusts should be the main threat with various small clusters that can form/consolidate and subsequently spread north-northeastward through the early evening. This wind threat will be locally maximized where filtered diurnal heating can help steepen low-level lapse rates. ...Central High Plains... Relatively high-based thunderstorms may develop this afternoon across parts of the central High Plains, generally along/east of a weak surface trough. This region will be mostly displaced to the east of large-scale ascent associated with the upper low over the West. Even so, a narrow zone of weak to moderate instability should be in place across parts of central NE into western KS by peak afternoon heating. Although flow through low/mid levels should remain modest for much of the afternoon, a veering wind profile with height should foster around 25-35 kt of deep-layer shear, sufficient for some updraft organization. The primary uncertainty regarding any isolated severe hail/wind threat remains whether convection will initiate or not. Have therefore not added a Marginal Risk across parts of the central High Plains with this update, but trends will continue to be monitored. ..Gleason/Supinie.. 09/16/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Mon Sep 16 2024 Valid 161630Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF NORTH DAKOTA INTO NORTHWEST MINNESOTA...AND EASTERN NORTH CAROLINA... ...SUMMARY... The threat for a few tornadoes will continue this afternoon and evening over eastern North Carolina and vicinity. Thunderstorms capable of producing severe gusts and large hail should occur today in parts of the northern Plains. Isolated severe wind and hail also appears possible across parts of the Great Basin to Four Corners. ...North Dakota into Northwest Minnesota... Elevated thunderstorms which have produced sporadic, marginally severe hail earlier this morning across parts of ND into northwest MN have generally remained sub-severe over the past couple of hours as a southerly low-level jet has gradually weakened. In the wake of this activity, a surface low should consolidate over the northern High Plains, with a front and convectively reinforced outflow expected to lift slowly northward across ND this afternoon/evening as an effective warm front. Airmass recovery is expected along/south of this boundary, with steepening mid-level lapse rates, moistening at low-levels, and daytime heating all contributing to moderate instability by later this afternoon. While low/mid-level flow will not be overly strong for most of the day, strengthening low-level southerly flow is expected again this evening as a low-level jet strengthens across the northern/central Plains. Current expectations are for robust thunderstorms to develop along/near the front late this afternoon and early evening. Enough deep-layer shear should be present to support a threat of large hail with any supercells initially. With time, some clustering should occur. A potentially greater wind threat may exist through the evening as activity spreads east-northeastward across central/eastern ND into northwest MN. A tornado or two also appears possible with any surface-based convection along/south of the front, especially this evening as 0-1 km shear increases with the strengthening low-level jet. ...Eastern North Carolina and Vicinity... The surface low off the NC/SC Coast (Potential Tropical Cyclone 8) is forecast by NHC to move northwest and inland across parts of SC through this evening. A surface trough/weak baroclinic zone extends northeastward from the low just off the NC Coast/Outer Banks. As the system moves inland, enhanced low-level flow should turn more east-southeasterly. Various NAM/RAP forecast soundings suggest that as low 70s surface dewpoints advance inland along the coastal plain of eastern NC, then only modest/filtered daytime heating will be needed to support weak boundary-layer destabilization. Sufficiently enlarged low-level hodographs should support a threat for a few tornadoes with any low-topped supercells that can form offshore and be sustained inland across coastal portions of eastern NC. The Slight Risk for this region has been maintained with only small adjustments based on recent observations and 12Z guidance. ...Great Basin into the Four Corners... A deep, closed upper low centered over CA this morning will advance slowly eastward across parts of the Great Basin through the period. An attendant south-southwesterly mid-level jet will overspread eastern portions of the Great Basin into the Four Corners region this afternoon and evening. Although cloud cover remains prevalent across parts of these areas, some daytime heating will encourage the development of weak instability by mid to late afternoon. Stronger mid-level flow and related deep-layer shear are forecast across the Four Corners vicinity, where marginal supercell structures could pose an isolated hail threat. Even though instability should generally remain weak owing to limited low-level moisture, occasional strong to severe wind gusts should be the main threat with various small clusters that can form/consolidate and subsequently spread north-northeastward through the early evening. This wind threat will be locally maximized where filtered diurnal heating can help steepen low-level lapse rates. ...Central High Plains... Relatively high-based thunderstorms may develop this afternoon across parts of the central High Plains, generally along/east of a weak surface trough. This region will be mostly displaced to the east of large-scale ascent associated with the upper low over the West. Even so, a narrow zone of weak to moderate instability should be in place across parts of central NE into western KS by peak afternoon heating. Although flow through low/mid levels should remain modest for much of the afternoon, a veering wind profile with height should foster around 25-35 kt of deep-layer shear, sufficient for some updraft organization. The primary uncertainty regarding any isolated severe hail/wind threat remains whether convection will initiate or not. Have therefore not added a Marginal Risk across parts of the central High Plains with this update, but trends will continue to be monitored. ..Gleason/Supinie.. 09/16/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Mon Sep 16 2024 Valid 161630Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF NORTH DAKOTA INTO NORTHWEST MINNESOTA...AND EASTERN NORTH CAROLINA... ...SUMMARY... The threat for a few tornadoes will continue this afternoon and evening over eastern North Carolina and vicinity. Thunderstorms capable of producing severe gusts and large hail should occur today in parts of the northern Plains. Isolated severe wind and hail also appears possible across parts of the Great Basin to Four Corners. ...North Dakota into Northwest Minnesota... Elevated thunderstorms which have produced sporadic, marginally severe hail earlier this morning across parts of ND into northwest MN have generally remained sub-severe over the past couple of hours as a southerly low-level jet has gradually weakened. In the wake of this activity, a surface low should consolidate over the northern High Plains, with a front and convectively reinforced outflow expected to lift slowly northward across ND this afternoon/evening as an effective warm front. Airmass recovery is expected along/south of this boundary, with steepening mid-level lapse rates, moistening at low-levels, and daytime heating all contributing to moderate instability by later this afternoon. While low/mid-level flow will not be overly strong for most of the day, strengthening low-level southerly flow is expected again this evening as a low-level jet strengthens across the northern/central Plains. Current expectations are for robust thunderstorms to develop along/near the front late this afternoon and early evening. Enough deep-layer shear should be present to support a threat of large hail with any supercells initially. With time, some clustering should occur. A potentially greater wind threat may exist through the evening as activity spreads east-northeastward across central/eastern ND into northwest MN. A tornado or two also appears possible with any surface-based convection along/south of the front, especially this evening as 0-1 km shear increases with the strengthening low-level jet. ...Eastern North Carolina and Vicinity... The surface low off the NC/SC Coast (Potential Tropical Cyclone 8) is forecast by NHC to move northwest and inland across parts of SC through this evening. A surface trough/weak baroclinic zone extends northeastward from the low just off the NC Coast/Outer Banks. As the system moves inland, enhanced low-level flow should turn more east-southeasterly. Various NAM/RAP forecast soundings suggest that as low 70s surface dewpoints advance inland along the coastal plain of eastern NC, then only modest/filtered daytime heating will be needed to support weak boundary-layer destabilization. Sufficiently enlarged low-level hodographs should support a threat for a few tornadoes with any low-topped supercells that can form offshore and be sustained inland across coastal portions of eastern NC. The Slight Risk for this region has been maintained with only small adjustments based on recent observations and 12Z guidance. ...Great Basin into the Four Corners... A deep, closed upper low centered over CA this morning will advance slowly eastward across parts of the Great Basin through the period. An attendant south-southwesterly mid-level jet will overspread eastern portions of the Great Basin into the Four Corners region this afternoon and evening. Although cloud cover remains prevalent across parts of these areas, some daytime heating will encourage the development of weak instability by mid to late afternoon. Stronger mid-level flow and related deep-layer shear are forecast across the Four Corners vicinity, where marginal supercell structures could pose an isolated hail threat. Even though instability should generally remain weak owing to limited low-level moisture, occasional strong to severe wind gusts should be the main threat with various small clusters that can form/consolidate and subsequently spread north-northeastward through the early evening. This wind threat will be locally maximized where filtered diurnal heating can help steepen low-level lapse rates. ...Central High Plains... Relatively high-based thunderstorms may develop this afternoon across parts of the central High Plains, generally along/east of a weak surface trough. This region will be mostly displaced to the east of large-scale ascent associated with the upper low over the West. Even so, a narrow zone of weak to moderate instability should be in place across parts of central NE into western KS by peak afternoon heating. Although flow through low/mid levels should remain modest for much of the afternoon, a veering wind profile with height should foster around 25-35 kt of deep-layer shear, sufficient for some updraft organization. The primary uncertainty regarding any isolated severe hail/wind threat remains whether convection will initiate or not. Have therefore not added a Marginal Risk across parts of the central High Plains with this update, but trends will continue to be monitored. ..Gleason/Supinie.. 09/16/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Mon Sep 16 2024 Valid 161630Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF NORTH DAKOTA INTO NORTHWEST MINNESOTA...AND EASTERN NORTH CAROLINA... ...SUMMARY... The threat for a few tornadoes will continue this afternoon and evening over eastern North Carolina and vicinity. Thunderstorms capable of producing severe gusts and large hail should occur today in parts of the northern Plains. Isolated severe wind and hail also appears possible across parts of the Great Basin to Four Corners. ...North Dakota into Northwest Minnesota... Elevated thunderstorms which have produced sporadic, marginally severe hail earlier this morning across parts of ND into northwest MN have generally remained sub-severe over the past couple of hours as a southerly low-level jet has gradually weakened. In the wake of this activity, a surface low should consolidate over the northern High Plains, with a front and convectively reinforced outflow expected to lift slowly northward across ND this afternoon/evening as an effective warm front. Airmass recovery is expected along/south of this boundary, with steepening mid-level lapse rates, moistening at low-levels, and daytime heating all contributing to moderate instability by later this afternoon. While low/mid-level flow will not be overly strong for most of the day, strengthening low-level southerly flow is expected again this evening as a low-level jet strengthens across the northern/central Plains. Current expectations are for robust thunderstorms to develop along/near the front late this afternoon and early evening. Enough deep-layer shear should be present to support a threat of large hail with any supercells initially. With time, some clustering should occur. A potentially greater wind threat may exist through the evening as activity spreads east-northeastward across central/eastern ND into northwest MN. A tornado or two also appears possible with any surface-based convection along/south of the front, especially this evening as 0-1 km shear increases with the strengthening low-level jet. ...Eastern North Carolina and Vicinity... The surface low off the NC/SC Coast (Potential Tropical Cyclone 8) is forecast by NHC to move northwest and inland across parts of SC through this evening. A surface trough/weak baroclinic zone extends northeastward from the low just off the NC Coast/Outer Banks. As the system moves inland, enhanced low-level flow should turn more east-southeasterly. Various NAM/RAP forecast soundings suggest that as low 70s surface dewpoints advance inland along the coastal plain of eastern NC, then only modest/filtered daytime heating will be needed to support weak boundary-layer destabilization. Sufficiently enlarged low-level hodographs should support a threat for a few tornadoes with any low-topped supercells that can form offshore and be sustained inland across coastal portions of eastern NC. The Slight Risk for this region has been maintained with only small adjustments based on recent observations and 12Z guidance. ...Great Basin into the Four Corners... A deep, closed upper low centered over CA this morning will advance slowly eastward across parts of the Great Basin through the period. An attendant south-southwesterly mid-level jet will overspread eastern portions of the Great Basin into the Four Corners region this afternoon and evening. Although cloud cover remains prevalent across parts of these areas, some daytime heating will encourage the development of weak instability by mid to late afternoon. Stronger mid-level flow and related deep-layer shear are forecast across the Four Corners vicinity, where marginal supercell structures could pose an isolated hail threat. Even though instability should generally remain weak owing to limited low-level moisture, occasional strong to severe wind gusts should be the main threat with various small clusters that can form/consolidate and subsequently spread north-northeastward through the early evening. This wind threat will be locally maximized where filtered diurnal heating can help steepen low-level lapse rates. ...Central High Plains... Relatively high-based thunderstorms may develop this afternoon across parts of the central High Plains, generally along/east of a weak surface trough. This region will be mostly displaced to the east of large-scale ascent associated with the upper low over the West. Even so, a narrow zone of weak to moderate instability should be in place across parts of central NE into western KS by peak afternoon heating. Although flow through low/mid levels should remain modest for much of the afternoon, a veering wind profile with height should foster around 25-35 kt of deep-layer shear, sufficient for some updraft organization. The primary uncertainty regarding any isolated severe hail/wind threat remains whether convection will initiate or not. Have therefore not added a Marginal Risk across parts of the central High Plains with this update, but trends will continue to be monitored. ..Gleason/Supinie.. 09/16/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Mon Sep 16 2024 Valid 161630Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF NORTH DAKOTA INTO NORTHWEST MINNESOTA...AND EASTERN NORTH CAROLINA... ...SUMMARY... The threat for a few tornadoes will continue this afternoon and evening over eastern North Carolina and vicinity. Thunderstorms capable of producing severe gusts and large hail should occur today in parts of the northern Plains. Isolated severe wind and hail also appears possible across parts of the Great Basin to Four Corners. ...North Dakota into Northwest Minnesota... Elevated thunderstorms which have produced sporadic, marginally severe hail earlier this morning across parts of ND into northwest MN have generally remained sub-severe over the past couple of hours as a southerly low-level jet has gradually weakened. In the wake of this activity, a surface low should consolidate over the northern High Plains, with a front and convectively reinforced outflow expected to lift slowly northward across ND this afternoon/evening as an effective warm front. Airmass recovery is expected along/south of this boundary, with steepening mid-level lapse rates, moistening at low-levels, and daytime heating all contributing to moderate instability by later this afternoon. While low/mid-level flow will not be overly strong for most of the day, strengthening low-level southerly flow is expected again this evening as a low-level jet strengthens across the northern/central Plains. Current expectations are for robust thunderstorms to develop along/near the front late this afternoon and early evening. Enough deep-layer shear should be present to support a threat of large hail with any supercells initially. With time, some clustering should occur. A potentially greater wind threat may exist through the evening as activity spreads east-northeastward across central/eastern ND into northwest MN. A tornado or two also appears possible with any surface-based convection along/south of the front, especially this evening as 0-1 km shear increases with the strengthening low-level jet. ...Eastern North Carolina and Vicinity... The surface low off the NC/SC Coast (Potential Tropical Cyclone 8) is forecast by NHC to move northwest and inland across parts of SC through this evening. A surface trough/weak baroclinic zone extends northeastward from the low just off the NC Coast/Outer Banks. As the system moves inland, enhanced low-level flow should turn more east-southeasterly. Various NAM/RAP forecast soundings suggest that as low 70s surface dewpoints advance inland along the coastal plain of eastern NC, then only modest/filtered daytime heating will be needed to support weak boundary-layer destabilization. Sufficiently enlarged low-level hodographs should support a threat for a few tornadoes with any low-topped supercells that can form offshore and be sustained inland across coastal portions of eastern NC. The Slight Risk for this region has been maintained with only small adjustments based on recent observations and 12Z guidance. ...Great Basin into the Four Corners... A deep, closed upper low centered over CA this morning will advance slowly eastward across parts of the Great Basin through the period. An attendant south-southwesterly mid-level jet will overspread eastern portions of the Great Basin into the Four Corners region this afternoon and evening. Although cloud cover remains prevalent across parts of these areas, some daytime heating will encourage the development of weak instability by mid to late afternoon. Stronger mid-level flow and related deep-layer shear are forecast across the Four Corners vicinity, where marginal supercell structures could pose an isolated hail threat. Even though instability should generally remain weak owing to limited low-level moisture, occasional strong to severe wind gusts should be the main threat with various small clusters that can form/consolidate and subsequently spread north-northeastward through the early evening. This wind threat will be locally maximized where filtered diurnal heating can help steepen low-level lapse rates. ...Central High Plains... Relatively high-based thunderstorms may develop this afternoon across parts of the central High Plains, generally along/east of a weak surface trough. This region will be mostly displaced to the east of large-scale ascent associated with the upper low over the West. Even so, a narrow zone of weak to moderate instability should be in place across parts of central NE into western KS by peak afternoon heating. Although flow through low/mid levels should remain modest for much of the afternoon, a veering wind profile with height should foster around 25-35 kt of deep-layer shear, sufficient for some updraft organization. The primary uncertainty regarding any isolated severe hail/wind threat remains whether convection will initiate or not. Have therefore not added a Marginal Risk across parts of the central High Plains with this update, but trends will continue to be monitored. ..Gleason/Supinie.. 09/16/2024 Read more

A farm that sells produce in Killen closed temporarily due to drought, but would normally stay open through the end of September. The heat and drought took a toll on the pumpkin patch, okra, zucchini, cucumber and spring crops. The farm will reopen the first weekend in October. WHNT News 19 (Huntsville, Ala.), Sept 4, 2024

Organic farmers in Hillsboro were already using their winter hay supply to feed their livestock as pastures dried up. Two streams have run dry. The farmer was praying for rain. Some neighbors who were unable to locate hay or water for their herds were selling cattle. One cut his herd by 18%, while another reduced his herd by 27%. WCPO-TV ABC 9 Cincinnati (Ohio), Sept 5, 2024

Some Tri-State farmers were harvesting crops early after the dry August weather. A Posey County, Indiana farmer noted that parts of fields had dried up and been dead since about June. WFIE-TV NBC 14 Evansville (Ind.), Sept 10, 2024

Drought has affected all aspects of a Boone County farm. Hay fields and pastures were dry, and livestock were being fed hay rather than grazing on grass in the pasture. Hay cuttings have been reduced in the number of rolls of hay produced. The pumpkin patch was growing slowly and not yielding pumpkins as it usually does. Pumpkins will likely have to be purchased from elsewhere. WLWT-TV NBC 5 Cincinnati (Ohio), Sept 11, 2024

MD 2070 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR FAR SOUTHERN NC COAST
Mesoscale Discussion 2070 NWS Storm Prediction Center Norman OK 0724 AM CDT Mon Sep 16 2024 Areas affected...Far Southern NC Coast Concerning...Severe potential...Watch unlikely Valid 161224Z - 161430Z Probability of Watch Issuance...20 percent SUMMARY...A low-probability tornado risk could develop across far southern coastal North Carolina as Potential Tropical Cyclone 8 approaches the region. DISCUSSION...The area of low pressure (dubbed Potential Tropical Cyclone 8 by NHC) off the southern NC/northern SC continues to slowly move northwestward towards the coast. Abundant precipitation to the northwest of this low has been ongoing across the southern/central NC coast for much of the night, limiting destabilization. Even so, a more buoyant airmass likely exists just offshore, as evidenced by the recent lightning within the deep convection about 30 miles south-southeast of ILM. Gradual northwestward progression of the low could bring this more buoyant air onshore over the immediate southern NC Coast. Strong low-level wind fields exist around this low, as sampled by the LTX VAD, and a few areas of transient low-level rotation have been noted from the LTX radar as well. General expectation is for most of the deeper convection to remain offshore for the next few hours, with the exception of the previously mentioned immediate coast of southern NC. Here, there is a chance of more persistent deep convection which could support a low-probability tornado risk. ..Mosier/Edwards.. 09/16/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...ILM... LAT...LON 33777841 33987849 34507804 34307751 33767795 33777841 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0746 AM CDT Mon Sep 16 2024 Valid 161300Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN THE EASTERN CAROLINAS AND PARTS OF THE NORTHERN PLAINS... ...SUMMARY... A tornado threat exists in the eastern Carolinas. Thunderstorms capable of severe gusts and large hail are expected today in parts of the northern Plains. Isolated severe wind and hail are expected in parts of the Four Corners and Great Basin. ...Synopsis... A highly amplified pattern is expected in mid/upper levels, anchored by two cyclones: 1. A purely cold-core, midlatitude circulation initially centered over northern CA, with accompanying cyclonic flow covering most of the CONUS from the Rockies westward. Equatorward progression of this feature is about done, and the 500-mb low should pivot eastward across the RNO area by 00Z, then east-northeastward toward EKO overnight. In the downstream difluent flow, a shortwave trough is apparent in moisture-channel imagery over the western Dakotas. This feature should move northeastward to southwestern MB by 00Z, then to westernmost parts of northwest ON overnight. 2. What is now a small, deep-layer circulation just offshore from ILM and MYR, designated Potential Tropical Cyclone 8 by NHC as of this writing. This system may become subtropical or tropical before moving inland later today, per NHC discussions. Regardless of whether it is named, the system will offer some tornado potential (below). The associated mid/upper low is progged to become better defined through the day and moving farther inland, with the low-level center tracking not far behind. As the surface, aside from PTC 8 and its attached frontal zone, the 11Z analysis showed a quasistationary front extending northeastward from a low near SHR, across southeastern MT to north-central ND, behind the outflow of a mass of ongoing convection over ND. The outflow boundary should act as the effective frontal zone for this region, as it moves slowly eastward over ND and north-central SD before likely stalling around midday. ...Eastern Carolinas... A zone of enhanced low-level gradient flow is apparent north through northeast of the center of PTC 8, over coastal sections of NC and westward past MYR. This is related both to the cyclone itself and antecedent/post-frontal high pressure from north of the baroclinic zone upon which this low developed. The synoptically driven baroclinicity is expected to continue to decrease (frontolysis), especially if this low becomes tropical. However, some mesoscale baroclinicity will remain due to persistent rain north of the old front, and a lack of precip -- combined with a high-theta-e, maritime/tropical airmass to its south and southeast. This airmass should shift northward as the low moves inland, and support potential for inland penetration of enough moisture and limited diurnal heating to enable 500-1000 J/kg MLCAPE today, away from areas of continual/persistent rainfall. In an environment where LCLs are low and low-level shear and SRH already are favorable (per VWP from ILM and MHX), the tornado threat will be tied directly to a combination of 1. Sufficient surface-based destabilization on the mesobeta scale, in that transition zone where flow still is backed enough to keep hodographs large, and 2. Formation of supercell(s) and their ability to remain in the favorably buoyant/backed-flow slot long enough to mature and produce. See SPC mesoscale discussion 2070 for marginal, near-term potential near and north of center. Through the day, the effective warm- frontal regime is expected to shift northward up the coastline and, to some extent, areas around the Sounds, so a small unconditional 5%/"slight risk" has been introduced in those areas. Tonight into tomorrow morning, as the center penetrates deeper inland away from the most favorable airmass and weakens considerably, and as diabatic cooling reduces instability at the surface, the tornado potential should diminish. ...Northern Plains... A large area of precip and convection is ongoing across much of west-central/central and northeastern ND, with embedded strong/ isolated severe thunderstorms capable of gusts and hail. This activity is reinforcing/reorienting the antecedent baroclinic zone across the area, and may persist northeastward into the remainder of northeastern ND and northwestern MN through midday with a continued threat for isolated severe. Additional development is possible along the outflow-modulated boundary, both in the near term and through the afternoon, ahead of the shortwave trough, and in the area of related maximized lift (both convective-scale on the boundary, and broader-scale in the midlevel DCVA). The airmass south and east of the boundary should heat diurnally, steepening the low/middle-level lapse rates amidst favorable 60 F surface dewpoints. This should support peak/preconvective MLCAPE in the 1500-2500 J/kg range, along with veering flow with height. However, lack of stronger midlevel flow limits deep shear, keeping progged effective-shear magnitudes generally under 35 kt. The most probable convective mode appears to be a mix of multicells and messy supercells. Convection-allowing progs that most-closely depicted the current state (which has not included the underdone hourly HRRR for most of the night) reasonably show a lack of substantial destabilization north of the boundary, except perhaps for some elevated hail potential this evening. Convective coverage on ether side of the boundary may increase for a few hours this evening in response to enhancement of moisture, shear and storm-relative flow provides by the LLJ. ...4 Corners/Great Basin... A broad arc of combined baroclinic and large-scale ascent is expected to extend across the near-eastern to far-southeastern sectors of the mid/upper cyclone, supporting episodic, widely scattered to scattered thunderstorms throughout much of the period. Where this activity encounters diurnally/diabatically destabilized boundary layers, characterized by deep mixing with related maximization of lapse rates and DCAPE, and at least marginal CAPE above, isolated severe gusts will be a threat. The potential for high-based supercells amidst greater shear to the southeast, across the Four Corners area, suggest isolated severe hail also will be possible there. ..Edwards/Mosier.. 09/16/2024 Read more