Severe Storms

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0232 PM CDT Sat Aug 17 2024 Valid 181200Z - 191200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHWEST NEVADA... A critical area has been added to southwest Nevada with this update. Here, conditions tomorrow (Sunday) should be similar to today (Saturday). Relative humidity should fall below 10% over a sizeable portion of the area, with numerical guidance indicating increasing confidence of winds in the afternoon approaching 20 mph. Elsewhere, the forecast remains on track. ..Marsh.. 08/17/2024 .PREV DISCUSSION... /ISSUED 0153 AM CDT Sat Aug 17 2024/ ...Synopsis... A mid-level trough will continue to meander along the West Coast while upper ridging persists across the central U.S. tomorrow (Sunday). A 500 mb speed max within the upper trough should progress northward toward the Pacific Northwest and International border, with a gradual weakening in isallobaric flow expected to the lee of the Cascades and Sierra. Nonetheless, boundary-layer mixing will promote Elevated dry and breezy conditions in terrain-favoring locations east of the Sierra into the Great Basin by afternoon, where Elevated highlights have been introduced. ...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 0232 PM CDT Sat Aug 17 2024 Valid 181200Z - 191200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHWEST NEVADA... A critical area has been added to southwest Nevada with this update. Here, conditions tomorrow (Sunday) should be similar to today (Saturday). Relative humidity should fall below 10% over a sizeable portion of the area, with numerical guidance indicating increasing confidence of winds in the afternoon approaching 20 mph. Elsewhere, the forecast remains on track. ..Marsh.. 08/17/2024 .PREV DISCUSSION... /ISSUED 0153 AM CDT Sat Aug 17 2024/ ...Synopsis... A mid-level trough will continue to meander along the West Coast while upper ridging persists across the central U.S. tomorrow (Sunday). A 500 mb speed max within the upper trough should progress northward toward the Pacific Northwest and International border, with a gradual weakening in isallobaric flow expected to the lee of the Cascades and Sierra. Nonetheless, boundary-layer mixing will promote Elevated dry and breezy conditions in terrain-favoring locations east of the Sierra into the Great Basin by afternoon, where Elevated highlights have been introduced. ...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 0232 PM CDT Sat Aug 17 2024 Valid 181200Z - 191200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHWEST NEVADA... A critical area has been added to southwest Nevada with this update. Here, conditions tomorrow (Sunday) should be similar to today (Saturday). Relative humidity should fall below 10% over a sizeable portion of the area, with numerical guidance indicating increasing confidence of winds in the afternoon approaching 20 mph. Elsewhere, the forecast remains on track. ..Marsh.. 08/17/2024 .PREV DISCUSSION... /ISSUED 0153 AM CDT Sat Aug 17 2024/ ...Synopsis... A mid-level trough will continue to meander along the West Coast while upper ridging persists across the central U.S. tomorrow (Sunday). A 500 mb speed max within the upper trough should progress northward toward the Pacific Northwest and International border, with a gradual weakening in isallobaric flow expected to the lee of the Cascades and Sierra. Nonetheless, boundary-layer mixing will promote Elevated dry and breezy conditions in terrain-favoring locations east of the Sierra into the Great Basin by afternoon, where Elevated highlights have been introduced. ...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 0232 PM CDT Sat Aug 17 2024 Valid 181200Z - 191200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHWEST NEVADA... A critical area has been added to southwest Nevada with this update. Here, conditions tomorrow (Sunday) should be similar to today (Saturday). Relative humidity should fall below 10% over a sizeable portion of the area, with numerical guidance indicating increasing confidence of winds in the afternoon approaching 20 mph. Elsewhere, the forecast remains on track. ..Marsh.. 08/17/2024 .PREV DISCUSSION... /ISSUED 0153 AM CDT Sat Aug 17 2024/ ...Synopsis... A mid-level trough will continue to meander along the West Coast while upper ridging persists across the central U.S. tomorrow (Sunday). A 500 mb speed max within the upper trough should progress northward toward the Pacific Northwest and International border, with a gradual weakening in isallobaric flow expected to the lee of the Cascades and Sierra. Nonetheless, boundary-layer mixing will promote Elevated dry and breezy conditions in terrain-favoring locations east of the Sierra into the Great Basin by afternoon, where Elevated highlights have been introduced. ...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 0232 PM CDT Sat Aug 17 2024 Valid 181200Z - 191200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHWEST NEVADA... A critical area has been added to southwest Nevada with this update. Here, conditions tomorrow (Sunday) should be similar to today (Saturday). Relative humidity should fall below 10% over a sizeable portion of the area, with numerical guidance indicating increasing confidence of winds in the afternoon approaching 20 mph. Elsewhere, the forecast remains on track. ..Marsh.. 08/17/2024 .PREV DISCUSSION... /ISSUED 0153 AM CDT Sat Aug 17 2024/ ...Synopsis... A mid-level trough will continue to meander along the West Coast while upper ridging persists across the central U.S. tomorrow (Sunday). A 500 mb speed max within the upper trough should progress northward toward the Pacific Northwest and International border, with a gradual weakening in isallobaric flow expected to the lee of the Cascades and Sierra. Nonetheless, boundary-layer mixing will promote Elevated dry and breezy conditions in terrain-favoring locations east of the Sierra into the Great Basin by afternoon, where Elevated highlights have been introduced. ...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 0232 PM CDT Sat Aug 17 2024 Valid 181200Z - 191200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHWEST NEVADA... A critical area has been added to southwest Nevada with this update. Here, conditions tomorrow (Sunday) should be similar to today (Saturday). Relative humidity should fall below 10% over a sizeable portion of the area, with numerical guidance indicating increasing confidence of winds in the afternoon approaching 20 mph. Elsewhere, the forecast remains on track. ..Marsh.. 08/17/2024 .PREV DISCUSSION... /ISSUED 0153 AM CDT Sat Aug 17 2024/ ...Synopsis... A mid-level trough will continue to meander along the West Coast while upper ridging persists across the central U.S. tomorrow (Sunday). A 500 mb speed max within the upper trough should progress northward toward the Pacific Northwest and International border, with a gradual weakening in isallobaric flow expected to the lee of the Cascades and Sierra. Nonetheless, boundary-layer mixing will promote Elevated dry and breezy conditions in terrain-favoring locations east of the Sierra into the Great Basin by afternoon, where Elevated highlights have been introduced. ...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 0232 PM CDT Sat Aug 17 2024 Valid 181200Z - 191200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHWEST NEVADA... A critical area has been added to southwest Nevada with this update. Here, conditions tomorrow (Sunday) should be similar to today (Saturday). Relative humidity should fall below 10% over a sizeable portion of the area, with numerical guidance indicating increasing confidence of winds in the afternoon approaching 20 mph. Elsewhere, the forecast remains on track. ..Marsh.. 08/17/2024 .PREV DISCUSSION... /ISSUED 0153 AM CDT Sat Aug 17 2024/ ...Synopsis... A mid-level trough will continue to meander along the West Coast while upper ridging persists across the central U.S. tomorrow (Sunday). A 500 mb speed max within the upper trough should progress northward toward the Pacific Northwest and International border, with a gradual weakening in isallobaric flow expected to the lee of the Cascades and Sierra. Nonetheless, boundary-layer mixing will promote Elevated dry and breezy conditions in terrain-favoring locations east of the Sierra into the Great Basin by afternoon, where Elevated highlights have been introduced. ...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 0232 PM CDT Sat Aug 17 2024 Valid 181200Z - 191200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHWEST NEVADA... A critical area has been added to southwest Nevada with this update. Here, conditions tomorrow (Sunday) should be similar to today (Saturday). Relative humidity should fall below 10% over a sizeable portion of the area, with numerical guidance indicating increasing confidence of winds in the afternoon approaching 20 mph. Elsewhere, the forecast remains on track. ..Marsh.. 08/17/2024 .PREV DISCUSSION... /ISSUED 0153 AM CDT Sat Aug 17 2024/ ...Synopsis... A mid-level trough will continue to meander along the West Coast while upper ridging persists across the central U.S. tomorrow (Sunday). A 500 mb speed max within the upper trough should progress northward toward the Pacific Northwest and International border, with a gradual weakening in isallobaric flow expected to the lee of the Cascades and Sierra. Nonetheless, boundary-layer mixing will promote Elevated dry and breezy conditions in terrain-favoring locations east of the Sierra into the Great Basin by afternoon, where Elevated highlights have been introduced. ...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 0232 PM CDT Sat Aug 17 2024 Valid 181200Z - 191200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHWEST NEVADA... A critical area has been added to southwest Nevada with this update. Here, conditions tomorrow (Sunday) should be similar to today (Saturday). Relative humidity should fall below 10% over a sizeable portion of the area, with numerical guidance indicating increasing confidence of winds in the afternoon approaching 20 mph. Elsewhere, the forecast remains on track. ..Marsh.. 08/17/2024 .PREV DISCUSSION... /ISSUED 0153 AM CDT Sat Aug 17 2024/ ...Synopsis... A mid-level trough will continue to meander along the West Coast while upper ridging persists across the central U.S. tomorrow (Sunday). A 500 mb speed max within the upper trough should progress northward toward the Pacific Northwest and International border, with a gradual weakening in isallobaric flow expected to the lee of the Cascades and Sierra. Nonetheless, boundary-layer mixing will promote Elevated dry and breezy conditions in terrain-favoring locations east of the Sierra into the Great Basin by afternoon, where Elevated highlights have been introduced. ...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 0232 PM CDT Sat Aug 17 2024 Valid 181200Z - 191200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHWEST NEVADA... A critical area has been added to southwest Nevada with this update. Here, conditions tomorrow (Sunday) should be similar to today (Saturday). Relative humidity should fall below 10% over a sizeable portion of the area, with numerical guidance indicating increasing confidence of winds in the afternoon approaching 20 mph. Elsewhere, the forecast remains on track. ..Marsh.. 08/17/2024 .PREV DISCUSSION... /ISSUED 0153 AM CDT Sat Aug 17 2024/ ...Synopsis... A mid-level trough will continue to meander along the West Coast while upper ridging persists across the central U.S. tomorrow (Sunday). A 500 mb speed max within the upper trough should progress northward toward the Pacific Northwest and International border, with a gradual weakening in isallobaric flow expected to the lee of the Cascades and Sierra. Nonetheless, boundary-layer mixing will promote Elevated dry and breezy conditions in terrain-favoring locations east of the Sierra into the Great Basin by afternoon, where Elevated highlights have been introduced. ...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 0232 PM CDT Sat Aug 17 2024 Valid 181200Z - 191200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHWEST NEVADA... A critical area has been added to southwest Nevada with this update. Here, conditions tomorrow (Sunday) should be similar to today (Saturday). Relative humidity should fall below 10% over a sizeable portion of the area, with numerical guidance indicating increasing confidence of winds in the afternoon approaching 20 mph. Elsewhere, the forecast remains on track. ..Marsh.. 08/17/2024 .PREV DISCUSSION... /ISSUED 0153 AM CDT Sat Aug 17 2024/ ...Synopsis... A mid-level trough will continue to meander along the West Coast while upper ridging persists across the central U.S. tomorrow (Sunday). A 500 mb speed max within the upper trough should progress northward toward the Pacific Northwest and International border, with a gradual weakening in isallobaric flow expected to the lee of the Cascades and Sierra. Nonetheless, boundary-layer mixing will promote Elevated dry and breezy conditions in terrain-favoring locations east of the Sierra into the Great Basin by afternoon, where Elevated highlights have been introduced. ...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 0232 PM CDT Sat Aug 17 2024 Valid 181200Z - 191200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHWEST NEVADA... A critical area has been added to southwest Nevada with this update. Here, conditions tomorrow (Sunday) should be similar to today (Saturday). Relative humidity should fall below 10% over a sizeable portion of the area, with numerical guidance indicating increasing confidence of winds in the afternoon approaching 20 mph. Elsewhere, the forecast remains on track. ..Marsh.. 08/17/2024 .PREV DISCUSSION... /ISSUED 0153 AM CDT Sat Aug 17 2024/ ...Synopsis... A mid-level trough will continue to meander along the West Coast while upper ridging persists across the central U.S. tomorrow (Sunday). A 500 mb speed max within the upper trough should progress northward toward the Pacific Northwest and International border, with a gradual weakening in isallobaric flow expected to the lee of the Cascades and Sierra. Nonetheless, boundary-layer mixing will promote Elevated dry and breezy conditions in terrain-favoring locations east of the Sierra into the Great Basin by afternoon, where Elevated highlights have been introduced. ...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 0232 PM CDT Sat Aug 17 2024 Valid 181200Z - 191200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHWEST NEVADA... A critical area has been added to southwest Nevada with this update. Here, conditions tomorrow (Sunday) should be similar to today (Saturday). Relative humidity should fall below 10% over a sizeable portion of the area, with numerical guidance indicating increasing confidence of winds in the afternoon approaching 20 mph. Elsewhere, the forecast remains on track. ..Marsh.. 08/17/2024 .PREV DISCUSSION... /ISSUED 0153 AM CDT Sat Aug 17 2024/ ...Synopsis... A mid-level trough will continue to meander along the West Coast while upper ridging persists across the central U.S. tomorrow (Sunday). A 500 mb speed max within the upper trough should progress northward toward the Pacific Northwest and International border, with a gradual weakening in isallobaric flow expected to the lee of the Cascades and Sierra. Nonetheless, boundary-layer mixing will promote Elevated dry and breezy conditions in terrain-favoring locations east of the Sierra into the Great Basin by afternoon, where Elevated highlights have been introduced. ...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 0232 PM CDT Sat Aug 17 2024 Valid 181200Z - 191200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHWEST NEVADA... A critical area has been added to southwest Nevada with this update. Here, conditions tomorrow (Sunday) should be similar to today (Saturday). Relative humidity should fall below 10% over a sizeable portion of the area, with numerical guidance indicating increasing confidence of winds in the afternoon approaching 20 mph. Elsewhere, the forecast remains on track. ..Marsh.. 08/17/2024 .PREV DISCUSSION... /ISSUED 0153 AM CDT Sat Aug 17 2024/ ...Synopsis... A mid-level trough will continue to meander along the West Coast while upper ridging persists across the central U.S. tomorrow (Sunday). A 500 mb speed max within the upper trough should progress northward toward the Pacific Northwest and International border, with a gradual weakening in isallobaric flow expected to the lee of the Cascades and Sierra. Nonetheless, boundary-layer mixing will promote Elevated dry and breezy conditions in terrain-favoring locations east of the Sierra into the Great Basin by afternoon, where Elevated highlights have been introduced. ...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 0232 PM CDT Sat Aug 17 2024 Valid 181200Z - 191200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHWEST NEVADA... A critical area has been added to southwest Nevada with this update. Here, conditions tomorrow (Sunday) should be similar to today (Saturday). Relative humidity should fall below 10% over a sizeable portion of the area, with numerical guidance indicating increasing confidence of winds in the afternoon approaching 20 mph. Elsewhere, the forecast remains on track. ..Marsh.. 08/17/2024 .PREV DISCUSSION... /ISSUED 0153 AM CDT Sat Aug 17 2024/ ...Synopsis... A mid-level trough will continue to meander along the West Coast while upper ridging persists across the central U.S. tomorrow (Sunday). A 500 mb speed max within the upper trough should progress northward toward the Pacific Northwest and International border, with a gradual weakening in isallobaric flow expected to the lee of the Cascades and Sierra. Nonetheless, boundary-layer mixing will promote Elevated dry and breezy conditions in terrain-favoring locations east of the Sierra into the Great Basin by afternoon, where Elevated highlights have been introduced. ...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 0232 PM CDT Sat Aug 17 2024 Valid 181200Z - 191200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHWEST NEVADA... A critical area has been added to southwest Nevada with this update. Here, conditions tomorrow (Sunday) should be similar to today (Saturday). Relative humidity should fall below 10% over a sizeable portion of the area, with numerical guidance indicating increasing confidence of winds in the afternoon approaching 20 mph. Elsewhere, the forecast remains on track. ..Marsh.. 08/17/2024 .PREV DISCUSSION... /ISSUED 0153 AM CDT Sat Aug 17 2024/ ...Synopsis... A mid-level trough will continue to meander along the West Coast while upper ridging persists across the central U.S. tomorrow (Sunday). A 500 mb speed max within the upper trough should progress northward toward the Pacific Northwest and International border, with a gradual weakening in isallobaric flow expected to the lee of the Cascades and Sierra. Nonetheless, boundary-layer mixing will promote Elevated dry and breezy conditions in terrain-favoring locations east of the Sierra into the Great Basin by afternoon, where Elevated highlights have been introduced. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

MD 1931 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR NORTHWEST ARIZONA TO NORTH-CENTRAL UTAH
Mesoscale Discussion 1931 NWS Storm Prediction Center Norman OK 1252 PM CDT Sat Aug 17 2024 Areas affected...northwest Arizona to north-central Utah Concerning...Severe potential...Watch possible Valid 171752Z - 171945Z Probability of Watch Issuance...60 percent SUMMARY...Severe wind gusts are possible with high-based storms this afternoon and evening from northwest Arizona to north-central Utah. DISCUSSION...Numerous elevated thunderstorms developed earlier this morning on the leading edge of a northward surge of monsoon moisture. In the wake of this convection, clear skies have allowed for sufficient surface heating which, when combined with the increasing low-level moisture, has resulted in moderate destabilization. SPC mesoanalysis suggests inhibition has mostly eroded. Therefore, surface-based storms, with likely a greater severe wind threat, are possible within the next 1 to 2 hours as further warming/moistening occurs. An environment this afternoon featuring high-based storms and a deeply-mixed boundary layer with 1000-1500 J/kg MLCAPE and 25-30 knots of effective shear should support some threat for severe wind gusts. With multiple rounds of storms possible, a severe thunderstorm watch may be needed to address this threat. ..Bentley/Hart.. 08/17/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...FGZ...SLC...VEF... LAT...LON 36591423 38751377 39551345 40181302 40531196 40271123 38711119 37291165 36821196 35861252 35711307 36181375 36591423 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0220 PM CDT Sat Aug 17 2024 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN THE NORTHERN/CENTRAL HIGH PLAINS...THE LOWER MID-ATLANTIC...AND THE SABINE VALLEY... ...SUMMARY... Isolated severe storms are possible across parts of the northern Great Plains to central High Plains, the Lower Mid-Atlantic States, and the Sabine Valley on Monday afternoon into the evening. ...Central High to northern Great Plains... A mid/upper trough should stall near the WA/southern BC coast, while a downstream ridge flattens/drifts east from the central High Plains to the Dakotas. As these processes occur, the meridional flow regime over the Northwest should evolve into predominant southwesterlies, with some enhancement relative to Sunday in the lee of northern Rockies. Fairly extensive convective coverage is likely towards mid to late afternoon as storms develop off the higher terrain within a broad plume of adequate 700-mb moisture and seasonably rich boundary-layer dew points across the northern/central High Plains. Deep-layer shear, especially with east and south extent, will be relatively modest. This suggests loosely to semi-organized clusters should dominate with isolated severe gusts as the primary threat. Localized severe hail is also possible, especially within the peak buoyancy axis across eastern MT to the Dakotas border area. ...Lower Mid-Atlantic... A large-scale mid/upper trough will drift east across southeast Canada to the South Atlantic coast. While severe potential appears to be less than on Sunday, embedded shortwave impulses and boundary-layer heating of a still richly moist air mass should support afternoon scattered thunderstorms focused on the Mid-Atlantic States into NC. A modest combination of deep-layer shear and MLCAPE should yield a threat for sporadic strong gusts. This may yield localized tree damage, peaking in the late afternoon. ...Sabine Valley... A conditionally adequate environment for a few marginally severe storms remains apparent along a persistent baroclinic/differential heating zone from the Lower Red River to Sabine Valleys. Bulk of guidance, outside of the 12Z GFS/GEFS, suggest convective potential should remain rather isolated inland of the Gulf Coast. If surface-based storms can be sustained, the western fringe of moderate north-northwesterly mid-level flow would foster potential for a few strong downbursts and small hail. ..Grams.. 08/17/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0220 PM CDT Sat Aug 17 2024 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN THE NORTHERN/CENTRAL HIGH PLAINS...THE LOWER MID-ATLANTIC...AND THE SABINE VALLEY... ...SUMMARY... Isolated severe storms are possible across parts of the northern Great Plains to central High Plains, the Lower Mid-Atlantic States, and the Sabine Valley on Monday afternoon into the evening. ...Central High to northern Great Plains... A mid/upper trough should stall near the WA/southern BC coast, while a downstream ridge flattens/drifts east from the central High Plains to the Dakotas. As these processes occur, the meridional flow regime over the Northwest should evolve into predominant southwesterlies, with some enhancement relative to Sunday in the lee of northern Rockies. Fairly extensive convective coverage is likely towards mid to late afternoon as storms develop off the higher terrain within a broad plume of adequate 700-mb moisture and seasonably rich boundary-layer dew points across the northern/central High Plains. Deep-layer shear, especially with east and south extent, will be relatively modest. This suggests loosely to semi-organized clusters should dominate with isolated severe gusts as the primary threat. Localized severe hail is also possible, especially within the peak buoyancy axis across eastern MT to the Dakotas border area. ...Lower Mid-Atlantic... A large-scale mid/upper trough will drift east across southeast Canada to the South Atlantic coast. While severe potential appears to be less than on Sunday, embedded shortwave impulses and boundary-layer heating of a still richly moist air mass should support afternoon scattered thunderstorms focused on the Mid-Atlantic States into NC. A modest combination of deep-layer shear and MLCAPE should yield a threat for sporadic strong gusts. This may yield localized tree damage, peaking in the late afternoon. ...Sabine Valley... A conditionally adequate environment for a few marginally severe storms remains apparent along a persistent baroclinic/differential heating zone from the Lower Red River to Sabine Valleys. Bulk of guidance, outside of the 12Z GFS/GEFS, suggest convective potential should remain rather isolated inland of the Gulf Coast. If surface-based storms can be sustained, the western fringe of moderate north-northwesterly mid-level flow would foster potential for a few strong downbursts and small hail. ..Grams.. 08/17/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0220 PM CDT Sat Aug 17 2024 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN THE NORTHERN/CENTRAL HIGH PLAINS...THE LOWER MID-ATLANTIC...AND THE SABINE VALLEY... ...SUMMARY... Isolated severe storms are possible across parts of the northern Great Plains to central High Plains, the Lower Mid-Atlantic States, and the Sabine Valley on Monday afternoon into the evening. ...Central High to northern Great Plains... A mid/upper trough should stall near the WA/southern BC coast, while a downstream ridge flattens/drifts east from the central High Plains to the Dakotas. As these processes occur, the meridional flow regime over the Northwest should evolve into predominant southwesterlies, with some enhancement relative to Sunday in the lee of northern Rockies. Fairly extensive convective coverage is likely towards mid to late afternoon as storms develop off the higher terrain within a broad plume of adequate 700-mb moisture and seasonably rich boundary-layer dew points across the northern/central High Plains. Deep-layer shear, especially with east and south extent, will be relatively modest. This suggests loosely to semi-organized clusters should dominate with isolated severe gusts as the primary threat. Localized severe hail is also possible, especially within the peak buoyancy axis across eastern MT to the Dakotas border area. ...Lower Mid-Atlantic... A large-scale mid/upper trough will drift east across southeast Canada to the South Atlantic coast. While severe potential appears to be less than on Sunday, embedded shortwave impulses and boundary-layer heating of a still richly moist air mass should support afternoon scattered thunderstorms focused on the Mid-Atlantic States into NC. A modest combination of deep-layer shear and MLCAPE should yield a threat for sporadic strong gusts. This may yield localized tree damage, peaking in the late afternoon. ...Sabine Valley... A conditionally adequate environment for a few marginally severe storms remains apparent along a persistent baroclinic/differential heating zone from the Lower Red River to Sabine Valleys. Bulk of guidance, outside of the 12Z GFS/GEFS, suggest convective potential should remain rather isolated inland of the Gulf Coast. If surface-based storms can be sustained, the western fringe of moderate north-northwesterly mid-level flow would foster potential for a few strong downbursts and small hail. ..Grams.. 08/17/2024 Read more