Aggregator

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0335 AM CDT Fri Aug 30 2024 Valid 021200Z - 071200Z ...DISCUSSION... Global models appear to be in reasonable agreement through the medium range, with a long-wave upper trough crossing the eastern U.S. Day 4/Monday, and then shifting into the Canadian Maritimes and western Atlantic Day 5/Tuesday. Weak/low-amplitude flow aloft will prevail across the U.S. Day 5 and into Day 6/Wednesday, before the pattern begins to amplify again through Days 7-8 (Thursday and Friday, Sept. 5-6). This amplification anticipated late in the period will result in an eastern trough/western ridge configuration, with a cold front to progress across the eastern half of the country through the second half of the period. However, with the prior (Day 3) frontal advance across the southern U.S., and persistence of Canadian surface high pressure in its wake, rich/Gulf moisture is expected to remain confined to southern portions of the country. This should limit severe potential with the late-period system as it crosses the CONUS. As such, no severe-weather risk areas are being included in the forecast, as overall potential appears likely at this time to remain low through the end of the upcoming week. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0335 AM CDT Fri Aug 30 2024 Valid 021200Z - 071200Z ...DISCUSSION... Global models appear to be in reasonable agreement through the medium range, with a long-wave upper trough crossing the eastern U.S. Day 4/Monday, and then shifting into the Canadian Maritimes and western Atlantic Day 5/Tuesday. Weak/low-amplitude flow aloft will prevail across the U.S. Day 5 and into Day 6/Wednesday, before the pattern begins to amplify again through Days 7-8 (Thursday and Friday, Sept. 5-6). This amplification anticipated late in the period will result in an eastern trough/western ridge configuration, with a cold front to progress across the eastern half of the country through the second half of the period. However, with the prior (Day 3) frontal advance across the southern U.S., and persistence of Canadian surface high pressure in its wake, rich/Gulf moisture is expected to remain confined to southern portions of the country. This should limit severe potential with the late-period system as it crosses the CONUS. As such, no severe-weather risk areas are being included in the forecast, as overall potential appears likely at this time to remain low through the end of the upcoming week. Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0233 AM CDT Fri Aug 30 2024 Valid 011200Z - 021200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM NEW ENGLAND TO THE CAROLINAS/SOUTHERN APPALACHIANS VICINITY... ...SUMMARY... Strong/isolated severe storms capable of producing gusty/damaging winds will be possible from New England to the Carolinas Sunday. ...Synopsis... A progressive/amplifying upper trough is forecast to continue shift eastward across eastern Canada/the eastern U.S. on Sunday, while upstream ridging prevails over the West. During the second half of the period (Sunday night), an eastern Pacific upper low should near/reach the Oregon/northern California Coast. At the surface, an initial cold front extending from New England to the Southeast will continue to dissipate. Meanwhile, a second/stronger front will continue shifting rapidly into the Northeast and across the Ohio Valley through the day, eventually overtaking the initial/weakening front. By Monday morning, the front will likely have moved off the New England and Mid-Atlantic Coasts, stretching westward from the Carolinas to Texas. ...New England to the Carolinas/southern Appalachians... As the reinforcing cold front advances quickly eastward/southeastward across the Northeast and central Appalachians Sunday, questions exist regarding potential for destabilization ahead of this front given the prior/dissipating front and associated convection lingering across the area at the start of the period. Presuming at least modest destabilization can occur, ascent along the advancing front combined with favorably strong flow aloft -- particularly across the Northeast -- would support fast-moving storms and attendant risk for damaging gusts through the afternoon and into the evening. While there are hints that sufficient moisture may linger across portions of New England to allow more substantial CAPE to evolve during the afternoon, which would yield greater severe potential, at this time uncertainty due to existing convection/cloud cover suggests that MRGL/5% risk remains most prudent at this time. ..Goss.. 08/30/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0233 AM CDT Fri Aug 30 2024 Valid 011200Z - 021200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM NEW ENGLAND TO THE CAROLINAS/SOUTHERN APPALACHIANS VICINITY... ...SUMMARY... Strong/isolated severe storms capable of producing gusty/damaging winds will be possible from New England to the Carolinas Sunday. ...Synopsis... A progressive/amplifying upper trough is forecast to continue shift eastward across eastern Canada/the eastern U.S. on Sunday, while upstream ridging prevails over the West. During the second half of the period (Sunday night), an eastern Pacific upper low should near/reach the Oregon/northern California Coast. At the surface, an initial cold front extending from New England to the Southeast will continue to dissipate. Meanwhile, a second/stronger front will continue shifting rapidly into the Northeast and across the Ohio Valley through the day, eventually overtaking the initial/weakening front. By Monday morning, the front will likely have moved off the New England and Mid-Atlantic Coasts, stretching westward from the Carolinas to Texas. ...New England to the Carolinas/southern Appalachians... As the reinforcing cold front advances quickly eastward/southeastward across the Northeast and central Appalachians Sunday, questions exist regarding potential for destabilization ahead of this front given the prior/dissipating front and associated convection lingering across the area at the start of the period. Presuming at least modest destabilization can occur, ascent along the advancing front combined with favorably strong flow aloft -- particularly across the Northeast -- would support fast-moving storms and attendant risk for damaging gusts through the afternoon and into the evening. While there are hints that sufficient moisture may linger across portions of New England to allow more substantial CAPE to evolve during the afternoon, which would yield greater severe potential, at this time uncertainty due to existing convection/cloud cover suggests that MRGL/5% risk remains most prudent at this time. ..Goss.. 08/30/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0233 AM CDT Fri Aug 30 2024 Valid 011200Z - 021200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM NEW ENGLAND TO THE CAROLINAS/SOUTHERN APPALACHIANS VICINITY... ...SUMMARY... Strong/isolated severe storms capable of producing gusty/damaging winds will be possible from New England to the Carolinas Sunday. ...Synopsis... A progressive/amplifying upper trough is forecast to continue shift eastward across eastern Canada/the eastern U.S. on Sunday, while upstream ridging prevails over the West. During the second half of the period (Sunday night), an eastern Pacific upper low should near/reach the Oregon/northern California Coast. At the surface, an initial cold front extending from New England to the Southeast will continue to dissipate. Meanwhile, a second/stronger front will continue shifting rapidly into the Northeast and across the Ohio Valley through the day, eventually overtaking the initial/weakening front. By Monday morning, the front will likely have moved off the New England and Mid-Atlantic Coasts, stretching westward from the Carolinas to Texas. ...New England to the Carolinas/southern Appalachians... As the reinforcing cold front advances quickly eastward/southeastward across the Northeast and central Appalachians Sunday, questions exist regarding potential for destabilization ahead of this front given the prior/dissipating front and associated convection lingering across the area at the start of the period. Presuming at least modest destabilization can occur, ascent along the advancing front combined with favorably strong flow aloft -- particularly across the Northeast -- would support fast-moving storms and attendant risk for damaging gusts through the afternoon and into the evening. While there are hints that sufficient moisture may linger across portions of New England to allow more substantial CAPE to evolve during the afternoon, which would yield greater severe potential, at this time uncertainty due to existing convection/cloud cover suggests that MRGL/5% risk remains most prudent at this time. ..Goss.. 08/30/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0233 AM CDT Fri Aug 30 2024 Valid 011200Z - 021200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM NEW ENGLAND TO THE CAROLINAS/SOUTHERN APPALACHIANS VICINITY... ...SUMMARY... Strong/isolated severe storms capable of producing gusty/damaging winds will be possible from New England to the Carolinas Sunday. ...Synopsis... A progressive/amplifying upper trough is forecast to continue shift eastward across eastern Canada/the eastern U.S. on Sunday, while upstream ridging prevails over the West. During the second half of the period (Sunday night), an eastern Pacific upper low should near/reach the Oregon/northern California Coast. At the surface, an initial cold front extending from New England to the Southeast will continue to dissipate. Meanwhile, a second/stronger front will continue shifting rapidly into the Northeast and across the Ohio Valley through the day, eventually overtaking the initial/weakening front. By Monday morning, the front will likely have moved off the New England and Mid-Atlantic Coasts, stretching westward from the Carolinas to Texas. ...New England to the Carolinas/southern Appalachians... As the reinforcing cold front advances quickly eastward/southeastward across the Northeast and central Appalachians Sunday, questions exist regarding potential for destabilization ahead of this front given the prior/dissipating front and associated convection lingering across the area at the start of the period. Presuming at least modest destabilization can occur, ascent along the advancing front combined with favorably strong flow aloft -- particularly across the Northeast -- would support fast-moving storms and attendant risk for damaging gusts through the afternoon and into the evening. While there are hints that sufficient moisture may linger across portions of New England to allow more substantial CAPE to evolve during the afternoon, which would yield greater severe potential, at this time uncertainty due to existing convection/cloud cover suggests that MRGL/5% risk remains most prudent at this time. ..Goss.. 08/30/2024 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0115 AM CDT Fri Aug 30 2024 Valid 311200Z - 011200Z ...Synopsis... Fire weather concerns will remain confined to portions of the Great Basin for Saturday. Upper-level ridging currently over the western CONUS will begin to slowly shift east towards the central Rockies over the next 48-72 hours. As this occurs, a modest plume of monsoonal moisture will spread north/northwest into southeastern NV and southwest UT. Weak mid/upper-level ascent impinging on the fringe of the moisture plume should support isolated thunderstorms by late afternoon. A deep, well-mixed boundary layer will promote limited rainfall with this activity over a region with generally receptive fuels (ERC values at/above the 80th percentile). Consequently, dry lightning will be a fire weather concern. Elsewhere across the West, dry conditions will persist, and increasing mid-level flow along the West Coast may support some breezy conditions in the immediate lee of the central to southern Sierra Nevada. However, confidence in widespread elevated conditions remains too limited for highlights. ..Moore.. 08/30/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0115 AM CDT Fri Aug 30 2024 Valid 311200Z - 011200Z ...Synopsis... Fire weather concerns will remain confined to portions of the Great Basin for Saturday. Upper-level ridging currently over the western CONUS will begin to slowly shift east towards the central Rockies over the next 48-72 hours. As this occurs, a modest plume of monsoonal moisture will spread north/northwest into southeastern NV and southwest UT. Weak mid/upper-level ascent impinging on the fringe of the moisture plume should support isolated thunderstorms by late afternoon. A deep, well-mixed boundary layer will promote limited rainfall with this activity over a region with generally receptive fuels (ERC values at/above the 80th percentile). Consequently, dry lightning will be a fire weather concern. Elsewhere across the West, dry conditions will persist, and increasing mid-level flow along the West Coast may support some breezy conditions in the immediate lee of the central to southern Sierra Nevada. However, confidence in widespread elevated conditions remains too limited for highlights. ..Moore.. 08/30/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0115 AM CDT Fri Aug 30 2024 Valid 311200Z - 011200Z ...Synopsis... Fire weather concerns will remain confined to portions of the Great Basin for Saturday. Upper-level ridging currently over the western CONUS will begin to slowly shift east towards the central Rockies over the next 48-72 hours. As this occurs, a modest plume of monsoonal moisture will spread north/northwest into southeastern NV and southwest UT. Weak mid/upper-level ascent impinging on the fringe of the moisture plume should support isolated thunderstorms by late afternoon. A deep, well-mixed boundary layer will promote limited rainfall with this activity over a region with generally receptive fuels (ERC values at/above the 80th percentile). Consequently, dry lightning will be a fire weather concern. Elsewhere across the West, dry conditions will persist, and increasing mid-level flow along the West Coast may support some breezy conditions in the immediate lee of the central to southern Sierra Nevada. However, confidence in widespread elevated conditions remains too limited for highlights. ..Moore.. 08/30/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0115 AM CDT Fri Aug 30 2024 Valid 311200Z - 011200Z ...Synopsis... Fire weather concerns will remain confined to portions of the Great Basin for Saturday. Upper-level ridging currently over the western CONUS will begin to slowly shift east towards the central Rockies over the next 48-72 hours. As this occurs, a modest plume of monsoonal moisture will spread north/northwest into southeastern NV and southwest UT. Weak mid/upper-level ascent impinging on the fringe of the moisture plume should support isolated thunderstorms by late afternoon. A deep, well-mixed boundary layer will promote limited rainfall with this activity over a region with generally receptive fuels (ERC values at/above the 80th percentile). Consequently, dry lightning will be a fire weather concern. Elsewhere across the West, dry conditions will persist, and increasing mid-level flow along the West Coast may support some breezy conditions in the immediate lee of the central to southern Sierra Nevada. However, confidence in widespread elevated conditions remains too limited for highlights. ..Moore.. 08/30/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0103 AM CDT Fri Aug 30 2024 Valid 311200Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE CENTRAL APPALACHIANS AREA... ...SUMMARY... Severe potential -- mainly in the form of damaging gusts -- is expected across portions of the northeast/central Appalachians and into the Tennessee and Ohio Valleys Saturday. A few strong/severe gusts may also occur over parts of the Upper Mississippi Valley vicinity during the afternoon. ...Synopsis... An upper trough moving across central Canada and the Great Lakes region will amplify modestly as it progresses eastward through Saturday night. Meanwhile, large-scale upper ridging will continue to prevail over the West. At the surface, a weakening cold front will continue moving eastward across the Lower Great Lakes and Ohio Valley into the Northeast and Tennessee Valley area through Saturday afternoon and evening. Meanwhile, a much stronger cold front is forecast to shift rapidly southeastward/southward out of Canada across the Upper Great Lakes and northern/central Plains through the period. ...Portions of the Northeast west-southwestward across the Ohio and Tennessee Valleys... As a weakening cold front shifts southeastward into the Northeast/across the Ohio Valley during the afternoon in tandem with weak mid-level height falls, heating/destabilization will support development of bands of thunderstorms across this region. The strongest flow aloft will remain across New York and into Pennsylvania, with weaker flow southwestward along the front. However, more substantial CAPE is expected farther south/southwest. The best juxtaposition of favorable kinematics and ample instability is forecast from portions of southeastern New York southwestward into the West Virginia/Maryland/northern Virginia vicinity. Here, locally damaging winds and some hail will be possible -- particularly during the afternoon hours. Lesser risk will extend southwestward -- potentially as far west-southwest as the middle Mississippi Valley area. ...Upper Mississippi Valley vicinity... As a strong cold front advances south-southeastward across the Northern Plains/Upper Great Lakes region ahead of a digging mid-level short-wave through, weak/rather low-topped instability is forecast to develop during the afternoon. This will support widely scattered thunderstorm development near the advancing front, within a very favorably strong kinematic environment. As such, fast-moving storms will be capable of producing gusty/damaging winds locally, before storms diminish after sunset. ..Goss.. 08/30/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0103 AM CDT Fri Aug 30 2024 Valid 311200Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE CENTRAL APPALACHIANS AREA... ...SUMMARY... Severe potential -- mainly in the form of damaging gusts -- is expected across portions of the northeast/central Appalachians and into the Tennessee and Ohio Valleys Saturday. A few strong/severe gusts may also occur over parts of the Upper Mississippi Valley vicinity during the afternoon. ...Synopsis... An upper trough moving across central Canada and the Great Lakes region will amplify modestly as it progresses eastward through Saturday night. Meanwhile, large-scale upper ridging will continue to prevail over the West. At the surface, a weakening cold front will continue moving eastward across the Lower Great Lakes and Ohio Valley into the Northeast and Tennessee Valley area through Saturday afternoon and evening. Meanwhile, a much stronger cold front is forecast to shift rapidly southeastward/southward out of Canada across the Upper Great Lakes and northern/central Plains through the period. ...Portions of the Northeast west-southwestward across the Ohio and Tennessee Valleys... As a weakening cold front shifts southeastward into the Northeast/across the Ohio Valley during the afternoon in tandem with weak mid-level height falls, heating/destabilization will support development of bands of thunderstorms across this region. The strongest flow aloft will remain across New York and into Pennsylvania, with weaker flow southwestward along the front. However, more substantial CAPE is expected farther south/southwest. The best juxtaposition of favorable kinematics and ample instability is forecast from portions of southeastern New York southwestward into the West Virginia/Maryland/northern Virginia vicinity. Here, locally damaging winds and some hail will be possible -- particularly during the afternoon hours. Lesser risk will extend southwestward -- potentially as far west-southwest as the middle Mississippi Valley area. ...Upper Mississippi Valley vicinity... As a strong cold front advances south-southeastward across the Northern Plains/Upper Great Lakes region ahead of a digging mid-level short-wave through, weak/rather low-topped instability is forecast to develop during the afternoon. This will support widely scattered thunderstorm development near the advancing front, within a very favorably strong kinematic environment. As such, fast-moving storms will be capable of producing gusty/damaging winds locally, before storms diminish after sunset. ..Goss.. 08/30/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0103 AM CDT Fri Aug 30 2024 Valid 311200Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE CENTRAL APPALACHIANS AREA... ...SUMMARY... Severe potential -- mainly in the form of damaging gusts -- is expected across portions of the northeast/central Appalachians and into the Tennessee and Ohio Valleys Saturday. A few strong/severe gusts may also occur over parts of the Upper Mississippi Valley vicinity during the afternoon. ...Synopsis... An upper trough moving across central Canada and the Great Lakes region will amplify modestly as it progresses eastward through Saturday night. Meanwhile, large-scale upper ridging will continue to prevail over the West. At the surface, a weakening cold front will continue moving eastward across the Lower Great Lakes and Ohio Valley into the Northeast and Tennessee Valley area through Saturday afternoon and evening. Meanwhile, a much stronger cold front is forecast to shift rapidly southeastward/southward out of Canada across the Upper Great Lakes and northern/central Plains through the period. ...Portions of the Northeast west-southwestward across the Ohio and Tennessee Valleys... As a weakening cold front shifts southeastward into the Northeast/across the Ohio Valley during the afternoon in tandem with weak mid-level height falls, heating/destabilization will support development of bands of thunderstorms across this region. The strongest flow aloft will remain across New York and into Pennsylvania, with weaker flow southwestward along the front. However, more substantial CAPE is expected farther south/southwest. The best juxtaposition of favorable kinematics and ample instability is forecast from portions of southeastern New York southwestward into the West Virginia/Maryland/northern Virginia vicinity. Here, locally damaging winds and some hail will be possible -- particularly during the afternoon hours. Lesser risk will extend southwestward -- potentially as far west-southwest as the middle Mississippi Valley area. ...Upper Mississippi Valley vicinity... As a strong cold front advances south-southeastward across the Northern Plains/Upper Great Lakes region ahead of a digging mid-level short-wave through, weak/rather low-topped instability is forecast to develop during the afternoon. This will support widely scattered thunderstorm development near the advancing front, within a very favorably strong kinematic environment. As such, fast-moving storms will be capable of producing gusty/damaging winds locally, before storms diminish after sunset. ..Goss.. 08/30/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0103 AM CDT Fri Aug 30 2024 Valid 311200Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE CENTRAL APPALACHIANS AREA... ...SUMMARY... Severe potential -- mainly in the form of damaging gusts -- is expected across portions of the northeast/central Appalachians and into the Tennessee and Ohio Valleys Saturday. A few strong/severe gusts may also occur over parts of the Upper Mississippi Valley vicinity during the afternoon. ...Synopsis... An upper trough moving across central Canada and the Great Lakes region will amplify modestly as it progresses eastward through Saturday night. Meanwhile, large-scale upper ridging will continue to prevail over the West. At the surface, a weakening cold front will continue moving eastward across the Lower Great Lakes and Ohio Valley into the Northeast and Tennessee Valley area through Saturday afternoon and evening. Meanwhile, a much stronger cold front is forecast to shift rapidly southeastward/southward out of Canada across the Upper Great Lakes and northern/central Plains through the period. ...Portions of the Northeast west-southwestward across the Ohio and Tennessee Valleys... As a weakening cold front shifts southeastward into the Northeast/across the Ohio Valley during the afternoon in tandem with weak mid-level height falls, heating/destabilization will support development of bands of thunderstorms across this region. The strongest flow aloft will remain across New York and into Pennsylvania, with weaker flow southwestward along the front. However, more substantial CAPE is expected farther south/southwest. The best juxtaposition of favorable kinematics and ample instability is forecast from portions of southeastern New York southwestward into the West Virginia/Maryland/northern Virginia vicinity. Here, locally damaging winds and some hail will be possible -- particularly during the afternoon hours. Lesser risk will extend southwestward -- potentially as far west-southwest as the middle Mississippi Valley area. ...Upper Mississippi Valley vicinity... As a strong cold front advances south-southeastward across the Northern Plains/Upper Great Lakes region ahead of a digging mid-level short-wave through, weak/rather low-topped instability is forecast to develop during the afternoon. This will support widely scattered thunderstorm development near the advancing front, within a very favorably strong kinematic environment. As such, fast-moving storms will be capable of producing gusty/damaging winds locally, before storms diminish after sunset. ..Goss.. 08/30/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0103 AM CDT Fri Aug 30 2024 Valid 311200Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE CENTRAL APPALACHIANS AREA... ...SUMMARY... Severe potential -- mainly in the form of damaging gusts -- is expected across portions of the northeast/central Appalachians and into the Tennessee and Ohio Valleys Saturday. A few strong/severe gusts may also occur over parts of the Upper Mississippi Valley vicinity during the afternoon. ...Synopsis... An upper trough moving across central Canada and the Great Lakes region will amplify modestly as it progresses eastward through Saturday night. Meanwhile, large-scale upper ridging will continue to prevail over the West. At the surface, a weakening cold front will continue moving eastward across the Lower Great Lakes and Ohio Valley into the Northeast and Tennessee Valley area through Saturday afternoon and evening. Meanwhile, a much stronger cold front is forecast to shift rapidly southeastward/southward out of Canada across the Upper Great Lakes and northern/central Plains through the period. ...Portions of the Northeast west-southwestward across the Ohio and Tennessee Valleys... As a weakening cold front shifts southeastward into the Northeast/across the Ohio Valley during the afternoon in tandem with weak mid-level height falls, heating/destabilization will support development of bands of thunderstorms across this region. The strongest flow aloft will remain across New York and into Pennsylvania, with weaker flow southwestward along the front. However, more substantial CAPE is expected farther south/southwest. The best juxtaposition of favorable kinematics and ample instability is forecast from portions of southeastern New York southwestward into the West Virginia/Maryland/northern Virginia vicinity. Here, locally damaging winds and some hail will be possible -- particularly during the afternoon hours. Lesser risk will extend southwestward -- potentially as far west-southwest as the middle Mississippi Valley area. ...Upper Mississippi Valley vicinity... As a strong cold front advances south-southeastward across the Northern Plains/Upper Great Lakes region ahead of a digging mid-level short-wave through, weak/rather low-topped instability is forecast to develop during the afternoon. This will support widely scattered thunderstorm development near the advancing front, within a very favorably strong kinematic environment. As such, fast-moving storms will be capable of producing gusty/damaging winds locally, before storms diminish after sunset. ..Goss.. 08/30/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1242 AM CDT Fri Aug 30 2024 Valid 301200Z - 311200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTHEAST LOWER MICHIGAN... ...SUMMARY... Scattered strong to severe storms are possible across eastern lower Michigan later today, with more isolated strong/severe storms into parts of the Midwest, and also across parts of the Carolinas and Virginia into northeast Georgia. ...Great Lakes/Midwest Region... Strong upper low, currently located over MB, will shift into northwest ON by the start of the period. Notable short-wave trough will advance from the upper MS Valley at 18z into the central Great Lakes by 31/12z. At the surface, synoptic front will advance into Lower MI-central IL-central OK by late afternoon. This boundary will serve as the focus for potential robust convection, especially as surface temperatures warm into the mid 80s. NAM forecast sounding for KDTW at 20z exhibits negligible CINH, with MLCAPE on the order of 2400 J/kg, though 0-6km bulk shear is seasonally weak. Deep-layer flow will increase a bit into the early evening hours, so updraft organization should be more favorable by this time. Even so, forecast lapse rates are marginal and this may limit overall severity. Southern extent of large-scale support should aid convective development ahead of the front. Some risk for wind/hail will exist with this activity. ...Southeast/Southern Middle Atlantic... Weak deep-layer flow will be noted across the southern Middle Atlantic and the Southeast today beneath the upper ridge. Boundary-layer heating will prove instrumental in convective development this afternoon, especially along a stalled synoptic front draped across NC/VA. Forecast soundings for this region suggest convective temperatures will be breached as early as 17z, and seasonally high PW values favor some risk for strong wind gusts within pulse-type updrafts. ..Darrow/Moore.. 08/30/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1242 AM CDT Fri Aug 30 2024 Valid 301200Z - 311200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTHEAST LOWER MICHIGAN... ...SUMMARY... Scattered strong to severe storms are possible across eastern lower Michigan later today, with more isolated strong/severe storms into parts of the Midwest, and also across parts of the Carolinas and Virginia into northeast Georgia. ...Great Lakes/Midwest Region... Strong upper low, currently located over MB, will shift into northwest ON by the start of the period. Notable short-wave trough will advance from the upper MS Valley at 18z into the central Great Lakes by 31/12z. At the surface, synoptic front will advance into Lower MI-central IL-central OK by late afternoon. This boundary will serve as the focus for potential robust convection, especially as surface temperatures warm into the mid 80s. NAM forecast sounding for KDTW at 20z exhibits negligible CINH, with MLCAPE on the order of 2400 J/kg, though 0-6km bulk shear is seasonally weak. Deep-layer flow will increase a bit into the early evening hours, so updraft organization should be more favorable by this time. Even so, forecast lapse rates are marginal and this may limit overall severity. Southern extent of large-scale support should aid convective development ahead of the front. Some risk for wind/hail will exist with this activity. ...Southeast/Southern Middle Atlantic... Weak deep-layer flow will be noted across the southern Middle Atlantic and the Southeast today beneath the upper ridge. Boundary-layer heating will prove instrumental in convective development this afternoon, especially along a stalled synoptic front draped across NC/VA. Forecast soundings for this region suggest convective temperatures will be breached as early as 17z, and seasonally high PW values favor some risk for strong wind gusts within pulse-type updrafts. ..Darrow/Moore.. 08/30/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1242 AM CDT Fri Aug 30 2024 Valid 301200Z - 311200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTHEAST LOWER MICHIGAN... ...SUMMARY... Scattered strong to severe storms are possible across eastern lower Michigan later today, with more isolated strong/severe storms into parts of the Midwest, and also across parts of the Carolinas and Virginia into northeast Georgia. ...Great Lakes/Midwest Region... Strong upper low, currently located over MB, will shift into northwest ON by the start of the period. Notable short-wave trough will advance from the upper MS Valley at 18z into the central Great Lakes by 31/12z. At the surface, synoptic front will advance into Lower MI-central IL-central OK by late afternoon. This boundary will serve as the focus for potential robust convection, especially as surface temperatures warm into the mid 80s. NAM forecast sounding for KDTW at 20z exhibits negligible CINH, with MLCAPE on the order of 2400 J/kg, though 0-6km bulk shear is seasonally weak. Deep-layer flow will increase a bit into the early evening hours, so updraft organization should be more favorable by this time. Even so, forecast lapse rates are marginal and this may limit overall severity. Southern extent of large-scale support should aid convective development ahead of the front. Some risk for wind/hail will exist with this activity. ...Southeast/Southern Middle Atlantic... Weak deep-layer flow will be noted across the southern Middle Atlantic and the Southeast today beneath the upper ridge. Boundary-layer heating will prove instrumental in convective development this afternoon, especially along a stalled synoptic front draped across NC/VA. Forecast soundings for this region suggest convective temperatures will be breached as early as 17z, and seasonally high PW values favor some risk for strong wind gusts within pulse-type updrafts. ..Darrow/Moore.. 08/30/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1242 AM CDT Fri Aug 30 2024 Valid 301200Z - 311200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTHEAST LOWER MICHIGAN... ...SUMMARY... Scattered strong to severe storms are possible across eastern lower Michigan later today, with more isolated strong/severe storms into parts of the Midwest, and also across parts of the Carolinas and Virginia into northeast Georgia. ...Great Lakes/Midwest Region... Strong upper low, currently located over MB, will shift into northwest ON by the start of the period. Notable short-wave trough will advance from the upper MS Valley at 18z into the central Great Lakes by 31/12z. At the surface, synoptic front will advance into Lower MI-central IL-central OK by late afternoon. This boundary will serve as the focus for potential robust convection, especially as surface temperatures warm into the mid 80s. NAM forecast sounding for KDTW at 20z exhibits negligible CINH, with MLCAPE on the order of 2400 J/kg, though 0-6km bulk shear is seasonally weak. Deep-layer flow will increase a bit into the early evening hours, so updraft organization should be more favorable by this time. Even so, forecast lapse rates are marginal and this may limit overall severity. Southern extent of large-scale support should aid convective development ahead of the front. Some risk for wind/hail will exist with this activity. ...Southeast/Southern Middle Atlantic... Weak deep-layer flow will be noted across the southern Middle Atlantic and the Southeast today beneath the upper ridge. Boundary-layer heating will prove instrumental in convective development this afternoon, especially along a stalled synoptic front draped across NC/VA. Forecast soundings for this region suggest convective temperatures will be breached as early as 17z, and seasonally high PW values favor some risk for strong wind gusts within pulse-type updrafts. ..Darrow/Moore.. 08/30/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1242 AM CDT Fri Aug 30 2024 Valid 301200Z - 311200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTHEAST LOWER MICHIGAN... ...SUMMARY... Scattered strong to severe storms are possible across eastern lower Michigan later today, with more isolated strong/severe storms into parts of the Midwest, and also across parts of the Carolinas and Virginia into northeast Georgia. ...Great Lakes/Midwest Region... Strong upper low, currently located over MB, will shift into northwest ON by the start of the period. Notable short-wave trough will advance from the upper MS Valley at 18z into the central Great Lakes by 31/12z. At the surface, synoptic front will advance into Lower MI-central IL-central OK by late afternoon. This boundary will serve as the focus for potential robust convection, especially as surface temperatures warm into the mid 80s. NAM forecast sounding for KDTW at 20z exhibits negligible CINH, with MLCAPE on the order of 2400 J/kg, though 0-6km bulk shear is seasonally weak. Deep-layer flow will increase a bit into the early evening hours, so updraft organization should be more favorable by this time. Even so, forecast lapse rates are marginal and this may limit overall severity. Southern extent of large-scale support should aid convective development ahead of the front. Some risk for wind/hail will exist with this activity. ...Southeast/Southern Middle Atlantic... Weak deep-layer flow will be noted across the southern Middle Atlantic and the Southeast today beneath the upper ridge. Boundary-layer heating will prove instrumental in convective development this afternoon, especially along a stalled synoptic front draped across NC/VA. Forecast soundings for this region suggest convective temperatures will be breached as early as 17z, and seasonally high PW values favor some risk for strong wind gusts within pulse-type updrafts. ..Darrow/Moore.. 08/30/2024 Read more