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SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1141 AM CDT Wed Aug 28 2024 Valid 281700Z - 291200Z The previous forecast (see below) remains on track, and no changes were needed with this update. ..Weinman.. 08/28/2024 .PREV DISCUSSION... /ISSUED 0149 AM CDT Wed Aug 28 2024/ ...Synopsis... A mid-level trough will traverse the northern Rockies today, encouraging strong surface lee troughing over the northern Plains. By afternoon, isallobaric and downslope flow will promote dry and windy conditions over portions of the central and northern Rockies. 15-25 mph sustained west-southwesterly surface winds will overlap with 15-20 percent RH, from portions of southeast Montana into central Wyoming. Elevated highlights have been maintained in central Wyoming, where dry and windy conditions will best overlap with fuels that are at least marginally receptive to wildfire spread. ...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 1141 AM CDT Wed Aug 28 2024 Valid 281700Z - 291200Z The previous forecast (see below) remains on track, and no changes were needed with this update. ..Weinman.. 08/28/2024 .PREV DISCUSSION... /ISSUED 0149 AM CDT Wed Aug 28 2024/ ...Synopsis... A mid-level trough will traverse the northern Rockies today, encouraging strong surface lee troughing over the northern Plains. By afternoon, isallobaric and downslope flow will promote dry and windy conditions over portions of the central and northern Rockies. 15-25 mph sustained west-southwesterly surface winds will overlap with 15-20 percent RH, from portions of southeast Montana into central Wyoming. Elevated highlights have been maintained in central Wyoming, where dry and windy conditions will best overlap with fuels that are at least marginally receptive to wildfire spread. ...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 1141 AM CDT Wed Aug 28 2024 Valid 281700Z - 291200Z The previous forecast (see below) remains on track, and no changes were needed with this update. ..Weinman.. 08/28/2024 .PREV DISCUSSION... /ISSUED 0149 AM CDT Wed Aug 28 2024/ ...Synopsis... A mid-level trough will traverse the northern Rockies today, encouraging strong surface lee troughing over the northern Plains. By afternoon, isallobaric and downslope flow will promote dry and windy conditions over portions of the central and northern Rockies. 15-25 mph sustained west-southwesterly surface winds will overlap with 15-20 percent RH, from portions of southeast Montana into central Wyoming. Elevated highlights have been maintained in central Wyoming, where dry and windy conditions will best overlap with fuels that are at least marginally receptive to wildfire spread. ...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 1141 AM CDT Wed Aug 28 2024 Valid 281700Z - 291200Z The previous forecast (see below) remains on track, and no changes were needed with this update. ..Weinman.. 08/28/2024 .PREV DISCUSSION... /ISSUED 0149 AM CDT Wed Aug 28 2024/ ...Synopsis... A mid-level trough will traverse the northern Rockies today, encouraging strong surface lee troughing over the northern Plains. By afternoon, isallobaric and downslope flow will promote dry and windy conditions over portions of the central and northern Rockies. 15-25 mph sustained west-southwesterly surface winds will overlap with 15-20 percent RH, from portions of southeast Montana into central Wyoming. Elevated highlights have been maintained in central Wyoming, where dry and windy conditions will best overlap with fuels that are at least marginally receptive to wildfire spread. ...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 1141 AM CDT Wed Aug 28 2024 Valid 281700Z - 291200Z The previous forecast (see below) remains on track, and no changes were needed with this update. ..Weinman.. 08/28/2024 .PREV DISCUSSION... /ISSUED 0149 AM CDT Wed Aug 28 2024/ ...Synopsis... A mid-level trough will traverse the northern Rockies today, encouraging strong surface lee troughing over the northern Plains. By afternoon, isallobaric and downslope flow will promote dry and windy conditions over portions of the central and northern Rockies. 15-25 mph sustained west-southwesterly surface winds will overlap with 15-20 percent RH, from portions of southeast Montana into central Wyoming. Elevated highlights have been maintained in central Wyoming, where dry and windy conditions will best overlap with fuels that are at least marginally receptive to wildfire spread. ...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 1141 AM CDT Wed Aug 28 2024 Valid 281700Z - 291200Z The previous forecast (see below) remains on track, and no changes were needed with this update. ..Weinman.. 08/28/2024 .PREV DISCUSSION... /ISSUED 0149 AM CDT Wed Aug 28 2024/ ...Synopsis... A mid-level trough will traverse the northern Rockies today, encouraging strong surface lee troughing over the northern Plains. By afternoon, isallobaric and downslope flow will promote dry and windy conditions over portions of the central and northern Rockies. 15-25 mph sustained west-southwesterly surface winds will overlap with 15-20 percent RH, from portions of southeast Montana into central Wyoming. Elevated highlights have been maintained in central Wyoming, where dry and windy conditions will best overlap with fuels that are at least marginally receptive to wildfire spread. ...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 1136 AM CDT Wed Aug 28 2024 Valid 281630Z - 291200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF NORTH DAKOTA/SOUTH DAKOTA... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE MIDWEST/OHIO VALLEY TO MID-ATLANTIC... ...SUMMARY... Severe thunderstorms are expected across parts of the Dakotas and from the Ohio Valley to the Mid-Atlantic Coast. ...Dakotas... Have upgraded portions of south-central North Dakota/north-central South Dakota to a categorical Enhanced Risk for what should be a relatively greater likelihood and concentration of severe storms late this afternoon through early/mid-evening. A prominent upper-level trough centered over western Montana and southern Alberta will continue generally eastward over the Canadian Prairies and toward the northern High Plains, with a trough-preceding/basal upper-level jet resulting in considerably strengthening southwesterly winds aloft by peak heating into tonight. This will be atop an increasingly moist boundary layer (dewpoints increasing through the 60s F) ahead of a surface low across South Dakota and a front extending northward into North Dakota. Thunderstorms should develop near the front by late afternoon/early evening, perhaps initially across North Dakota where overall forcing will be greater, and subsequently southward into South Dakota where richer low-level moisture and greater buoyancy will reside. Given steep lapse rates and the reservoir of instability, these initial storms should be supercells capable of very large hail amidst strengthening flow aloft. Large to very large hail and severe wind gusts will be the most common hazards, although a tornado risk may also exist particularly across north-central South Dakota/far south-central North Dakota near the surface low/warm front-related triple point where moisture/low-level SRH will be maximized. Over time, relatively weak mid-level flow may encourage a transition to messier, quasi-linear modes with embedded LEWP/bow formations for a few hours. Activity should weaken overnight as it moves into stabilizing boundary-layer air, though a 45-55-kt low-level jet may encourage persistence of a cluster or two tonight into the eastern Dakotas. ...Midwest/Ohio Valley to Mid-Atlantic States... Widely scattered to scattered thunderstorms will pose a risk for damaging winds particularly mid/late afternoon through early/mid-evening regionally. Some hail may also occur on a more marginal and isolated basis. This severe risk will primarily span parts of Indiana/Ohio eastward to the coastal Mid-Atlantic/Delmarva vicinity, although the overall extent and magnitude of today's risk is still a bit uncertain. The boundary layer will not be overly moist by late-summer standards, particularly across the middle Ohio River Valley, but a relatively richer moist axis (through the lowest 2-3 km AGL) extends this morning from the upper Ohio Valley eastward toward the coastal Mid-Atlantic/Northeast. The boundary layer will also not be overly unstable later today, with severe-adequate MLCAPE generally limited to 2000 J/kg MLCAPE. Aside from differential heating related to last night's convection across the Midwest, several impetuses for thunderstorm development to the south of the primary Great Lakes front may include the eastward transitions of MCVs across southeast Lower Michigan and north-central Illinois, which should be influential into the Lake Ontario/New York/northern Pennsylvania and lower/middle Ohio Valley vicinities, respectively, later this afternoon and evening. Effective shear will tend to be limited to 20-25 kt, but slowly-increasing-with-height deep-layer westerlies will support multicell-related damaging wind/some hail potential as low-level lapse rates steepen and the boundary layer moderately destabilizes this afternoon. ..Guyer/Wendt.. 08/28/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1136 AM CDT Wed Aug 28 2024 Valid 281630Z - 291200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF NORTH DAKOTA/SOUTH DAKOTA... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE MIDWEST/OHIO VALLEY TO MID-ATLANTIC... ...SUMMARY... Severe thunderstorms are expected across parts of the Dakotas and from the Ohio Valley to the Mid-Atlantic Coast. ...Dakotas... Have upgraded portions of south-central North Dakota/north-central South Dakota to a categorical Enhanced Risk for what should be a relatively greater likelihood and concentration of severe storms late this afternoon through early/mid-evening. A prominent upper-level trough centered over western Montana and southern Alberta will continue generally eastward over the Canadian Prairies and toward the northern High Plains, with a trough-preceding/basal upper-level jet resulting in considerably strengthening southwesterly winds aloft by peak heating into tonight. This will be atop an increasingly moist boundary layer (dewpoints increasing through the 60s F) ahead of a surface low across South Dakota and a front extending northward into North Dakota. Thunderstorms should develop near the front by late afternoon/early evening, perhaps initially across North Dakota where overall forcing will be greater, and subsequently southward into South Dakota where richer low-level moisture and greater buoyancy will reside. Given steep lapse rates and the reservoir of instability, these initial storms should be supercells capable of very large hail amidst strengthening flow aloft. Large to very large hail and severe wind gusts will be the most common hazards, although a tornado risk may also exist particularly across north-central South Dakota/far south-central North Dakota near the surface low/warm front-related triple point where moisture/low-level SRH will be maximized. Over time, relatively weak mid-level flow may encourage a transition to messier, quasi-linear modes with embedded LEWP/bow formations for a few hours. Activity should weaken overnight as it moves into stabilizing boundary-layer air, though a 45-55-kt low-level jet may encourage persistence of a cluster or two tonight into the eastern Dakotas. ...Midwest/Ohio Valley to Mid-Atlantic States... Widely scattered to scattered thunderstorms will pose a risk for damaging winds particularly mid/late afternoon through early/mid-evening regionally. Some hail may also occur on a more marginal and isolated basis. This severe risk will primarily span parts of Indiana/Ohio eastward to the coastal Mid-Atlantic/Delmarva vicinity, although the overall extent and magnitude of today's risk is still a bit uncertain. The boundary layer will not be overly moist by late-summer standards, particularly across the middle Ohio River Valley, but a relatively richer moist axis (through the lowest 2-3 km AGL) extends this morning from the upper Ohio Valley eastward toward the coastal Mid-Atlantic/Northeast. The boundary layer will also not be overly unstable later today, with severe-adequate MLCAPE generally limited to 2000 J/kg MLCAPE. Aside from differential heating related to last night's convection across the Midwest, several impetuses for thunderstorm development to the south of the primary Great Lakes front may include the eastward transitions of MCVs across southeast Lower Michigan and north-central Illinois, which should be influential into the Lake Ontario/New York/northern Pennsylvania and lower/middle Ohio Valley vicinities, respectively, later this afternoon and evening. Effective shear will tend to be limited to 20-25 kt, but slowly-increasing-with-height deep-layer westerlies will support multicell-related damaging wind/some hail potential as low-level lapse rates steepen and the boundary layer moderately destabilizes this afternoon. ..Guyer/Wendt.. 08/28/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1136 AM CDT Wed Aug 28 2024 Valid 281630Z - 291200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF NORTH DAKOTA/SOUTH DAKOTA... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE MIDWEST/OHIO VALLEY TO MID-ATLANTIC... ...SUMMARY... Severe thunderstorms are expected across parts of the Dakotas and from the Ohio Valley to the Mid-Atlantic Coast. ...Dakotas... Have upgraded portions of south-central North Dakota/north-central South Dakota to a categorical Enhanced Risk for what should be a relatively greater likelihood and concentration of severe storms late this afternoon through early/mid-evening. A prominent upper-level trough centered over western Montana and southern Alberta will continue generally eastward over the Canadian Prairies and toward the northern High Plains, with a trough-preceding/basal upper-level jet resulting in considerably strengthening southwesterly winds aloft by peak heating into tonight. This will be atop an increasingly moist boundary layer (dewpoints increasing through the 60s F) ahead of a surface low across South Dakota and a front extending northward into North Dakota. Thunderstorms should develop near the front by late afternoon/early evening, perhaps initially across North Dakota where overall forcing will be greater, and subsequently southward into South Dakota where richer low-level moisture and greater buoyancy will reside. Given steep lapse rates and the reservoir of instability, these initial storms should be supercells capable of very large hail amidst strengthening flow aloft. Large to very large hail and severe wind gusts will be the most common hazards, although a tornado risk may also exist particularly across north-central South Dakota/far south-central North Dakota near the surface low/warm front-related triple point where moisture/low-level SRH will be maximized. Over time, relatively weak mid-level flow may encourage a transition to messier, quasi-linear modes with embedded LEWP/bow formations for a few hours. Activity should weaken overnight as it moves into stabilizing boundary-layer air, though a 45-55-kt low-level jet may encourage persistence of a cluster or two tonight into the eastern Dakotas. ...Midwest/Ohio Valley to Mid-Atlantic States... Widely scattered to scattered thunderstorms will pose a risk for damaging winds particularly mid/late afternoon through early/mid-evening regionally. Some hail may also occur on a more marginal and isolated basis. This severe risk will primarily span parts of Indiana/Ohio eastward to the coastal Mid-Atlantic/Delmarva vicinity, although the overall extent and magnitude of today's risk is still a bit uncertain. The boundary layer will not be overly moist by late-summer standards, particularly across the middle Ohio River Valley, but a relatively richer moist axis (through the lowest 2-3 km AGL) extends this morning from the upper Ohio Valley eastward toward the coastal Mid-Atlantic/Northeast. The boundary layer will also not be overly unstable later today, with severe-adequate MLCAPE generally limited to 2000 J/kg MLCAPE. Aside from differential heating related to last night's convection across the Midwest, several impetuses for thunderstorm development to the south of the primary Great Lakes front may include the eastward transitions of MCVs across southeast Lower Michigan and north-central Illinois, which should be influential into the Lake Ontario/New York/northern Pennsylvania and lower/middle Ohio Valley vicinities, respectively, later this afternoon and evening. Effective shear will tend to be limited to 20-25 kt, but slowly-increasing-with-height deep-layer westerlies will support multicell-related damaging wind/some hail potential as low-level lapse rates steepen and the boundary layer moderately destabilizes this afternoon. ..Guyer/Wendt.. 08/28/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1136 AM CDT Wed Aug 28 2024 Valid 281630Z - 291200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF NORTH DAKOTA/SOUTH DAKOTA... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE MIDWEST/OHIO VALLEY TO MID-ATLANTIC... ...SUMMARY... Severe thunderstorms are expected across parts of the Dakotas and from the Ohio Valley to the Mid-Atlantic Coast. ...Dakotas... Have upgraded portions of south-central North Dakota/north-central South Dakota to a categorical Enhanced Risk for what should be a relatively greater likelihood and concentration of severe storms late this afternoon through early/mid-evening. A prominent upper-level trough centered over western Montana and southern Alberta will continue generally eastward over the Canadian Prairies and toward the northern High Plains, with a trough-preceding/basal upper-level jet resulting in considerably strengthening southwesterly winds aloft by peak heating into tonight. This will be atop an increasingly moist boundary layer (dewpoints increasing through the 60s F) ahead of a surface low across South Dakota and a front extending northward into North Dakota. Thunderstorms should develop near the front by late afternoon/early evening, perhaps initially across North Dakota where overall forcing will be greater, and subsequently southward into South Dakota where richer low-level moisture and greater buoyancy will reside. Given steep lapse rates and the reservoir of instability, these initial storms should be supercells capable of very large hail amidst strengthening flow aloft. Large to very large hail and severe wind gusts will be the most common hazards, although a tornado risk may also exist particularly across north-central South Dakota/far south-central North Dakota near the surface low/warm front-related triple point where moisture/low-level SRH will be maximized. Over time, relatively weak mid-level flow may encourage a transition to messier, quasi-linear modes with embedded LEWP/bow formations for a few hours. Activity should weaken overnight as it moves into stabilizing boundary-layer air, though a 45-55-kt low-level jet may encourage persistence of a cluster or two tonight into the eastern Dakotas. ...Midwest/Ohio Valley to Mid-Atlantic States... Widely scattered to scattered thunderstorms will pose a risk for damaging winds particularly mid/late afternoon through early/mid-evening regionally. Some hail may also occur on a more marginal and isolated basis. This severe risk will primarily span parts of Indiana/Ohio eastward to the coastal Mid-Atlantic/Delmarva vicinity, although the overall extent and magnitude of today's risk is still a bit uncertain. The boundary layer will not be overly moist by late-summer standards, particularly across the middle Ohio River Valley, but a relatively richer moist axis (through the lowest 2-3 km AGL) extends this morning from the upper Ohio Valley eastward toward the coastal Mid-Atlantic/Northeast. The boundary layer will also not be overly unstable later today, with severe-adequate MLCAPE generally limited to 2000 J/kg MLCAPE. Aside from differential heating related to last night's convection across the Midwest, several impetuses for thunderstorm development to the south of the primary Great Lakes front may include the eastward transitions of MCVs across southeast Lower Michigan and north-central Illinois, which should be influential into the Lake Ontario/New York/northern Pennsylvania and lower/middle Ohio Valley vicinities, respectively, later this afternoon and evening. Effective shear will tend to be limited to 20-25 kt, but slowly-increasing-with-height deep-layer westerlies will support multicell-related damaging wind/some hail potential as low-level lapse rates steepen and the boundary layer moderately destabilizes this afternoon. ..Guyer/Wendt.. 08/28/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1136 AM CDT Wed Aug 28 2024 Valid 281630Z - 291200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF NORTH DAKOTA/SOUTH DAKOTA... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE MIDWEST/OHIO VALLEY TO MID-ATLANTIC... ...SUMMARY... Severe thunderstorms are expected across parts of the Dakotas and from the Ohio Valley to the Mid-Atlantic Coast. ...Dakotas... Have upgraded portions of south-central North Dakota/north-central South Dakota to a categorical Enhanced Risk for what should be a relatively greater likelihood and concentration of severe storms late this afternoon through early/mid-evening. A prominent upper-level trough centered over western Montana and southern Alberta will continue generally eastward over the Canadian Prairies and toward the northern High Plains, with a trough-preceding/basal upper-level jet resulting in considerably strengthening southwesterly winds aloft by peak heating into tonight. This will be atop an increasingly moist boundary layer (dewpoints increasing through the 60s F) ahead of a surface low across South Dakota and a front extending northward into North Dakota. Thunderstorms should develop near the front by late afternoon/early evening, perhaps initially across North Dakota where overall forcing will be greater, and subsequently southward into South Dakota where richer low-level moisture and greater buoyancy will reside. Given steep lapse rates and the reservoir of instability, these initial storms should be supercells capable of very large hail amidst strengthening flow aloft. Large to very large hail and severe wind gusts will be the most common hazards, although a tornado risk may also exist particularly across north-central South Dakota/far south-central North Dakota near the surface low/warm front-related triple point where moisture/low-level SRH will be maximized. Over time, relatively weak mid-level flow may encourage a transition to messier, quasi-linear modes with embedded LEWP/bow formations for a few hours. Activity should weaken overnight as it moves into stabilizing boundary-layer air, though a 45-55-kt low-level jet may encourage persistence of a cluster or two tonight into the eastern Dakotas. ...Midwest/Ohio Valley to Mid-Atlantic States... Widely scattered to scattered thunderstorms will pose a risk for damaging winds particularly mid/late afternoon through early/mid-evening regionally. Some hail may also occur on a more marginal and isolated basis. This severe risk will primarily span parts of Indiana/Ohio eastward to the coastal Mid-Atlantic/Delmarva vicinity, although the overall extent and magnitude of today's risk is still a bit uncertain. The boundary layer will not be overly moist by late-summer standards, particularly across the middle Ohio River Valley, but a relatively richer moist axis (through the lowest 2-3 km AGL) extends this morning from the upper Ohio Valley eastward toward the coastal Mid-Atlantic/Northeast. The boundary layer will also not be overly unstable later today, with severe-adequate MLCAPE generally limited to 2000 J/kg MLCAPE. Aside from differential heating related to last night's convection across the Midwest, several impetuses for thunderstorm development to the south of the primary Great Lakes front may include the eastward transitions of MCVs across southeast Lower Michigan and north-central Illinois, which should be influential into the Lake Ontario/New York/northern Pennsylvania and lower/middle Ohio Valley vicinities, respectively, later this afternoon and evening. Effective shear will tend to be limited to 20-25 kt, but slowly-increasing-with-height deep-layer westerlies will support multicell-related damaging wind/some hail potential as low-level lapse rates steepen and the boundary layer moderately destabilizes this afternoon. ..Guyer/Wendt.. 08/28/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1136 AM CDT Wed Aug 28 2024 Valid 281630Z - 291200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF NORTH DAKOTA/SOUTH DAKOTA... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE MIDWEST/OHIO VALLEY TO MID-ATLANTIC... ...SUMMARY... Severe thunderstorms are expected across parts of the Dakotas and from the Ohio Valley to the Mid-Atlantic Coast. ...Dakotas... Have upgraded portions of south-central North Dakota/north-central South Dakota to a categorical Enhanced Risk for what should be a relatively greater likelihood and concentration of severe storms late this afternoon through early/mid-evening. A prominent upper-level trough centered over western Montana and southern Alberta will continue generally eastward over the Canadian Prairies and toward the northern High Plains, with a trough-preceding/basal upper-level jet resulting in considerably strengthening southwesterly winds aloft by peak heating into tonight. This will be atop an increasingly moist boundary layer (dewpoints increasing through the 60s F) ahead of a surface low across South Dakota and a front extending northward into North Dakota. Thunderstorms should develop near the front by late afternoon/early evening, perhaps initially across North Dakota where overall forcing will be greater, and subsequently southward into South Dakota where richer low-level moisture and greater buoyancy will reside. Given steep lapse rates and the reservoir of instability, these initial storms should be supercells capable of very large hail amidst strengthening flow aloft. Large to very large hail and severe wind gusts will be the most common hazards, although a tornado risk may also exist particularly across north-central South Dakota/far south-central North Dakota near the surface low/warm front-related triple point where moisture/low-level SRH will be maximized. Over time, relatively weak mid-level flow may encourage a transition to messier, quasi-linear modes with embedded LEWP/bow formations for a few hours. Activity should weaken overnight as it moves into stabilizing boundary-layer air, though a 45-55-kt low-level jet may encourage persistence of a cluster or two tonight into the eastern Dakotas. ...Midwest/Ohio Valley to Mid-Atlantic States... Widely scattered to scattered thunderstorms will pose a risk for damaging winds particularly mid/late afternoon through early/mid-evening regionally. Some hail may also occur on a more marginal and isolated basis. This severe risk will primarily span parts of Indiana/Ohio eastward to the coastal Mid-Atlantic/Delmarva vicinity, although the overall extent and magnitude of today's risk is still a bit uncertain. The boundary layer will not be overly moist by late-summer standards, particularly across the middle Ohio River Valley, but a relatively richer moist axis (through the lowest 2-3 km AGL) extends this morning from the upper Ohio Valley eastward toward the coastal Mid-Atlantic/Northeast. The boundary layer will also not be overly unstable later today, with severe-adequate MLCAPE generally limited to 2000 J/kg MLCAPE. Aside from differential heating related to last night's convection across the Midwest, several impetuses for thunderstorm development to the south of the primary Great Lakes front may include the eastward transitions of MCVs across southeast Lower Michigan and north-central Illinois, which should be influential into the Lake Ontario/New York/northern Pennsylvania and lower/middle Ohio Valley vicinities, respectively, later this afternoon and evening. Effective shear will tend to be limited to 20-25 kt, but slowly-increasing-with-height deep-layer westerlies will support multicell-related damaging wind/some hail potential as low-level lapse rates steepen and the boundary layer moderately destabilizes this afternoon. ..Guyer/Wendt.. 08/28/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1136 AM CDT Wed Aug 28 2024 Valid 281630Z - 291200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF NORTH DAKOTA/SOUTH DAKOTA... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE MIDWEST/OHIO VALLEY TO MID-ATLANTIC... ...SUMMARY... Severe thunderstorms are expected across parts of the Dakotas and from the Ohio Valley to the Mid-Atlantic Coast. ...Dakotas... Have upgraded portions of south-central North Dakota/north-central South Dakota to a categorical Enhanced Risk for what should be a relatively greater likelihood and concentration of severe storms late this afternoon through early/mid-evening. A prominent upper-level trough centered over western Montana and southern Alberta will continue generally eastward over the Canadian Prairies and toward the northern High Plains, with a trough-preceding/basal upper-level jet resulting in considerably strengthening southwesterly winds aloft by peak heating into tonight. This will be atop an increasingly moist boundary layer (dewpoints increasing through the 60s F) ahead of a surface low across South Dakota and a front extending northward into North Dakota. Thunderstorms should develop near the front by late afternoon/early evening, perhaps initially across North Dakota where overall forcing will be greater, and subsequently southward into South Dakota where richer low-level moisture and greater buoyancy will reside. Given steep lapse rates and the reservoir of instability, these initial storms should be supercells capable of very large hail amidst strengthening flow aloft. Large to very large hail and severe wind gusts will be the most common hazards, although a tornado risk may also exist particularly across north-central South Dakota/far south-central North Dakota near the surface low/warm front-related triple point where moisture/low-level SRH will be maximized. Over time, relatively weak mid-level flow may encourage a transition to messier, quasi-linear modes with embedded LEWP/bow formations for a few hours. Activity should weaken overnight as it moves into stabilizing boundary-layer air, though a 45-55-kt low-level jet may encourage persistence of a cluster or two tonight into the eastern Dakotas. ...Midwest/Ohio Valley to Mid-Atlantic States... Widely scattered to scattered thunderstorms will pose a risk for damaging winds particularly mid/late afternoon through early/mid-evening regionally. Some hail may also occur on a more marginal and isolated basis. This severe risk will primarily span parts of Indiana/Ohio eastward to the coastal Mid-Atlantic/Delmarva vicinity, although the overall extent and magnitude of today's risk is still a bit uncertain. The boundary layer will not be overly moist by late-summer standards, particularly across the middle Ohio River Valley, but a relatively richer moist axis (through the lowest 2-3 km AGL) extends this morning from the upper Ohio Valley eastward toward the coastal Mid-Atlantic/Northeast. The boundary layer will also not be overly unstable later today, with severe-adequate MLCAPE generally limited to 2000 J/kg MLCAPE. Aside from differential heating related to last night's convection across the Midwest, several impetuses for thunderstorm development to the south of the primary Great Lakes front may include the eastward transitions of MCVs across southeast Lower Michigan and north-central Illinois, which should be influential into the Lake Ontario/New York/northern Pennsylvania and lower/middle Ohio Valley vicinities, respectively, later this afternoon and evening. Effective shear will tend to be limited to 20-25 kt, but slowly-increasing-with-height deep-layer westerlies will support multicell-related damaging wind/some hail potential as low-level lapse rates steepen and the boundary layer moderately destabilizes this afternoon. ..Guyer/Wendt.. 08/28/2024 Read more

Cattle farmers in Wood County were feeding their livestock hay because pasture grass was not growing well. There was only a first cutting of hay, but no second cutting. The demand for hay was high because many were feeding cattle, which has led to hay shortages in the region and hay being imported from other states. Some were also buying and hauling water for livestock as springs and creeks have gone dry. The Marietta Times (Ohio), Aug 28, 2024

5-Day Uncertainty Track last updated Wed, 28 Aug 2024 14:34:31 GMT


Wind Speed Probabilities last updated Wed, 28 Aug 2024 15:35:03 GMT

Issued at 500 AM HST Wed Aug 28 2024 654 WTPZ43 KNHC 281433 TCDEP3 Tropical Storm Hector Discussion Number 12 NWS National Hurricane Center Miami FL EP082024 500 AM HST Wed Aug 28 2024 GOES-18 proxy-vis imagery shows that the low-level center of Hector is exposed to the southwest of a large area of deep convection. A 28/1040 UTC ATMS microwave pass also supports the analysis of the exposed center located to the southwest of the convection. An ASCAT-B pass from 28/0608 UTC showed wind vectors up to 38 kt to the north of the center. However, the ASCAT data also shows that the wind structure on the south side is becoming weak and elongated. Although the scatterometer data still shows some weak west winds on the south side, Hector could be close to opening up into a trough. Subjective current intensity estimates are 45 kt from both TAFB and SAB. Objective intensity estimates from UW-CIMSS are a bit lower, ranging from 35 to 44 kt. The initial intensity is held at 45 kt for this advisory. The center of Hector is becoming a bit more ambiguous as there appears to be a couple of weak swirls, and the best estimate of the motion is westward, or 275/9 kt. The cyclone should continue moving close to due west, steered by a low- to mid-level subtropical ridge to its north. The new NHC forecast is just a tad slower than the previous official forecast and is close to the TVCE consensus aid. Moderate west-southwesterly wind shear has already caused the convective area to be displaced well to the northeast of the center. Given that Hector is expected to continue traveling within an environment of marginal SSTs, dry air, and moderate southwesterly shear, the NHC forecast will continue to show weakening, in agreement with the latest intensity consensus guidance. Simulated satellite imagery from the GFS and ECMWF models suggests that Hector should lose its convection on Thursday, and the official forecast continues to show Hector degenerating to a remnant low at that time. Most of the global models show the remnants of Hector opening up into a trough by Friday. However, given the recent deteriorating surface wind structure observed on ASCAT and GOES-18 proxy vis imagery, it would not be surprising if Hector dissipated sooner than forecast. FORECAST POSITIONS AND MAX WINDS INIT 28/1500Z 18.3N 132.9W 45 KT 50 MPH 12H 29/0000Z 18.4N 134.5W 40 KT 45 MPH 24H 29/1200Z 18.5N 136.8W 35 KT 40 MPH 36H 30/0000Z 18.5N 139.4W 30 KT 35 MPH...POST-TROP/REMNT LOW 48H 30/1200Z 18.4N 142.3W 30 KT 35 MPH...POST-TROP/REMNT LOW 60H 31/0000Z...DISSIPATED $$ Forecaster Hagen/Reinhart/Konarik

Issued at 1500 UTC WED AUG 28 2024 000 FOPZ13 KNHC 281433 PWSEP3 TROPICAL STORM HECTOR WIND SPEED PROBABILITIES NUMBER 12 NWS NATIONAL HURRICANE CENTER MIAMI FL EP082024 1500 UTC WED AUG 28 2024 AT 1500Z THE CENTER OF TROPICAL STORM HECTOR WAS LOCATED NEAR LATITUDE 18.3 NORTH...LONGITUDE 132.9 WEST WITH MAXIMUM SUSTAINED WINDS NEAR 45 KTS...50 MPH...85 KM/H. Z INDICATES COORDINATED UNIVERSAL TIME (GREENWICH) PACIFIC DAYLIGHT TIME (PDT)...SUBTRACT 7 HOURS FROM Z TIME HAWAIIAN STANDARD TIME (HST)...SUBTRACT 10 HOURS FROM Z TIME WIND SPEED PROBABILITY TABLE FOR SPECIFIC LOCATIONS CHANCES OF SUSTAINED (1-MINUTE AVERAGE) WIND SPEEDS OF AT LEAST ...34 KT (39 MPH... 63 KM/H)... ...50 KT (58 MPH... 93 KM/H)... ...64 KT (74 MPH...119 KM/H)... FOR LOCATIONS AND TIME PERIODS DURING THE NEXT 5 DAYS PROBABILITIES FOR LOCATIONS ARE GIVEN AS OP(CP) WHERE OP IS THE PROBABILITY OF THE EVENT BEGINNING DURING AN INDIVIDUAL TIME PERIOD (ONSET PROBABILITY) (CP) IS THE PROBABILITY OF THE EVENT OCCURRING BETWEEN 12Z WED AND THE FORECAST HOUR (CUMULATIVE PROBABILITY) PROBABILITIES ARE GIVEN IN PERCENT X INDICATES PROBABILITIES LESS THAN 1 PERCENT PROBABILITIES FOR 34 KT AND 50 KT ARE SHOWN AT A GIVEN LOCATION WHEN THE 5-DAY CUMULATIVE PROBABILITY IS AT LEAST 3 PERCENT. PROBABILITIES FOR 34...50...64 KT SHOWN WHEN THE 5-DAY 64-KT CUMULATIVE PROBABILITY IS AT LEAST 1 PERCENT. - - - - WIND SPEED PROBABILITIES FOR SELECTED LOCATIONS - - - - FROM FROM FROM FROM FROM FROM FROM TIME 12Z WED 00Z THU 12Z THU 00Z FRI 12Z FRI 12Z SAT 12Z SUN PERIODS TO TO TO TO TO TO TO 00Z THU 12Z THU 00Z FRI 12Z FRI 12Z SAT 12Z SUN 12Z MON FORECAST HOUR (12) (24) (36) (48) (72) (96) (120) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - LOCATION KT 20N 135W 34 4 3( 7) X( 7) X( 7) X( 7) X( 7) X( 7) 20N 140W 34 X X( X) 4( 4) 2( 6) X( 6) X( 6) X( 6) $$ FORECASTER HAGEN/REINHART/KONARIK

Issued at 1500 UTC WED AUG 28 2024 000 WTPZ23 KNHC 281432 TCMEP3 TROPICAL STORM HECTOR FORECAST/ADVISORY NUMBER 12 NWS NATIONAL HURRICANE CENTER MIAMI FL EP082024 1500 UTC WED AUG 28 2024 TROPICAL STORM CENTER LOCATED NEAR 18.3N 132.9W AT 28/1500Z POSITION ACCURATE WITHIN 30 NM PRESENT MOVEMENT TOWARD THE WEST OR 275 DEGREES AT 9 KT ESTIMATED MINIMUM CENTRAL PRESSURE 1002 MB MAX SUSTAINED WINDS 45 KT WITH GUSTS TO 55 KT. 34 KT....... 70NE 0SE 0SW 60NW. 12 FT SEAS.. 60NE 0SE 30SW 60NW. WINDS AND SEAS VARY GREATLY IN EACH QUADRANT. RADII IN NAUTICAL MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT. REPEAT...CENTER LOCATED NEAR 18.3N 132.9W AT 28/1500Z AT 28/1200Z CENTER WAS LOCATED NEAR 18.3N 132.4W FORECAST VALID 29/0000Z 18.4N 134.5W MAX WIND 40 KT...GUSTS 50 KT. 34 KT... 50NE 0SE 0SW 40NW. FORECAST VALID 29/1200Z 18.5N 136.8W MAX WIND 35 KT...GUSTS 45 KT. 34 KT... 40NE 0SE 0SW 30NW. FORECAST VALID 30/0000Z 18.5N 139.4W...POST-TROP/REMNT LOW MAX WIND 30 KT...GUSTS 40 KT. FORECAST VALID 30/1200Z 18.4N 142.3W...POST-TROP/REMNT LOW MAX WIND 30 KT...GUSTS 40 KT. FORECAST VALID 31/0000Z...DISSIPATED REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 18.3N 132.9W NEXT ADVISORY AT 28/2100Z $$ FORECASTER HAGEN/REINHART/KONARIK

Issued at 500 AM HST Wed Aug 28 2024 000 WTPZ33 KNHC 281432 TCPEP3 BULLETIN Tropical Storm Hector Advisory Number 12 NWS National Hurricane Center Miami FL EP082024 500 AM HST Wed Aug 28 2024 ...HECTOR FORECAST TO WEAKEN SOON AS IT HEADS WESTWARD... SUMMARY OF 500 AM HST...1500 UTC...INFORMATION ---------------------------------------------- LOCATION...18.3N 132.9W ABOUT 1450 MI...2335 KM E OF HILO HAWAII MAXIMUM SUSTAINED WINDS...50 MPH...85 KM/H PRESENT MOVEMENT...W OR 275 DEGREES AT 10 MPH...17 KM/H MINIMUM CENTRAL PRESSURE...1002 MB...29.59 INCHES WATCHES AND WARNINGS -------------------- There are no coastal watches or warnings in effect. DISCUSSION AND OUTLOOK ---------------------- At 500 AM HST (1500 UTC), the center of Tropical Storm Hector was located near latitude 18.3 North, longitude 132.9 West. Hector is moving toward the west near 10 mph (17 km/h), and this motion is expected to continue for the next couple of days. Maximum sustained winds are near 50 mph (85 km/h) with higher gusts. Gradual weakening is anticipated during the next couple of days, and Hector is forecast to become a remnant low on Thursday. Tropical-storm-force winds extend outward up to 80 miles (130 km) from the center. The estimated minimum central pressure is 1002 mb (29.59 inches). HAZARDS AFFECTING LAND ---------------------- None NEXT ADVISORY ------------- Next complete advisory at 1100 AM HST. $$ Forecaster Hagen/Reinhart/Konarik

...HECTOR FORECAST TO WEAKEN SOON AS IT HEADS WESTWARD... As of 5:00 AM HST Wed Aug 28 the center of Hector was located near 18.3, -132.9 with movement W at 10 mph. The minimum central pressure was 1002 mb with maximum sustained winds of about 50 mph.