Severe Storms

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1113 AM CDT Sun Aug 11 2024 Valid 111700Z - 121200Z ...NO CRITICAL AREAS... A pair of isolated dry-thunderstorm risk areas have been introduced for this morning's forecast update. 12 UTC soundings from BOI and OTX sampled relatively dry low-level conditions and PWAT values similar to previous days that have seen a mixture of wet and dry thunderstorms. MRMS rainfall estimates and surface observations suggest that most locations have not received wetting rainfall over the past 48 hours with several lightning-caused fire starts have been reported during this period. Morning HREF guidance shows a signal for isolated convection this afternoon and early Tuesday morning with favorable thermodynamic profiles in place for a mixture of wet/dry thunderstorms. Given recent observations, the model signals, and antecedent fuel conditions, risk highlights appear warranted. Localized elevated conditions remain likely across west-central NV in the immediate lee of the northern Sierra Nevada as well as across portions of eastern NV. However, such conditions are expected to remain sufficiently localized to preclude highlights. ..Moore.. 08/11/2024 .PREV DISCUSSION... /ISSUED 1255 AM CDT Sun Aug 11 2024/ ...Synopsis... A belt of stronger mid-level winds will be present on the poleward side of a flattened upper-level ridge in the southern U.S. With time, a shortwave trough will amplify and move into northern California and the northwest Great Basin. At the surface, the pressure pattern will be rather disorganized until stronger pressure falls occur in the Northwest late in the period. Fire weather concerns are expected to be low for most areas today. Some locally elevated conditions are possible in parts of central/northern Nevada. RH will likely be in the 10-15% range, but winds will be light. The potential for thunderstorms over sufficiently dry fuels is also too low for highlights. ...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 1113 AM CDT Sun Aug 11 2024 Valid 111700Z - 121200Z ...NO CRITICAL AREAS... A pair of isolated dry-thunderstorm risk areas have been introduced for this morning's forecast update. 12 UTC soundings from BOI and OTX sampled relatively dry low-level conditions and PWAT values similar to previous days that have seen a mixture of wet and dry thunderstorms. MRMS rainfall estimates and surface observations suggest that most locations have not received wetting rainfall over the past 48 hours with several lightning-caused fire starts have been reported during this period. Morning HREF guidance shows a signal for isolated convection this afternoon and early Tuesday morning with favorable thermodynamic profiles in place for a mixture of wet/dry thunderstorms. Given recent observations, the model signals, and antecedent fuel conditions, risk highlights appear warranted. Localized elevated conditions remain likely across west-central NV in the immediate lee of the northern Sierra Nevada as well as across portions of eastern NV. However, such conditions are expected to remain sufficiently localized to preclude highlights. ..Moore.. 08/11/2024 .PREV DISCUSSION... /ISSUED 1255 AM CDT Sun Aug 11 2024/ ...Synopsis... A belt of stronger mid-level winds will be present on the poleward side of a flattened upper-level ridge in the southern U.S. With time, a shortwave trough will amplify and move into northern California and the northwest Great Basin. At the surface, the pressure pattern will be rather disorganized until stronger pressure falls occur in the Northwest late in the period. Fire weather concerns are expected to be low for most areas today. Some locally elevated conditions are possible in parts of central/northern Nevada. RH will likely be in the 10-15% range, but winds will be light. The potential for thunderstorms over sufficiently dry fuels is also too low for highlights. ...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 1113 AM CDT Sun Aug 11 2024 Valid 111700Z - 121200Z ...NO CRITICAL AREAS... A pair of isolated dry-thunderstorm risk areas have been introduced for this morning's forecast update. 12 UTC soundings from BOI and OTX sampled relatively dry low-level conditions and PWAT values similar to previous days that have seen a mixture of wet and dry thunderstorms. MRMS rainfall estimates and surface observations suggest that most locations have not received wetting rainfall over the past 48 hours with several lightning-caused fire starts have been reported during this period. Morning HREF guidance shows a signal for isolated convection this afternoon and early Tuesday morning with favorable thermodynamic profiles in place for a mixture of wet/dry thunderstorms. Given recent observations, the model signals, and antecedent fuel conditions, risk highlights appear warranted. Localized elevated conditions remain likely across west-central NV in the immediate lee of the northern Sierra Nevada as well as across portions of eastern NV. However, such conditions are expected to remain sufficiently localized to preclude highlights. ..Moore.. 08/11/2024 .PREV DISCUSSION... /ISSUED 1255 AM CDT Sun Aug 11 2024/ ...Synopsis... A belt of stronger mid-level winds will be present on the poleward side of a flattened upper-level ridge in the southern U.S. With time, a shortwave trough will amplify and move into northern California and the northwest Great Basin. At the surface, the pressure pattern will be rather disorganized until stronger pressure falls occur in the Northwest late in the period. Fire weather concerns are expected to be low for most areas today. Some locally elevated conditions are possible in parts of central/northern Nevada. RH will likely be in the 10-15% range, but winds will be light. The potential for thunderstorms over sufficiently dry fuels is also too low for highlights. ...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 1113 AM CDT Sun Aug 11 2024 Valid 111700Z - 121200Z ...NO CRITICAL AREAS... A pair of isolated dry-thunderstorm risk areas have been introduced for this morning's forecast update. 12 UTC soundings from BOI and OTX sampled relatively dry low-level conditions and PWAT values similar to previous days that have seen a mixture of wet and dry thunderstorms. MRMS rainfall estimates and surface observations suggest that most locations have not received wetting rainfall over the past 48 hours with several lightning-caused fire starts have been reported during this period. Morning HREF guidance shows a signal for isolated convection this afternoon and early Tuesday morning with favorable thermodynamic profiles in place for a mixture of wet/dry thunderstorms. Given recent observations, the model signals, and antecedent fuel conditions, risk highlights appear warranted. Localized elevated conditions remain likely across west-central NV in the immediate lee of the northern Sierra Nevada as well as across portions of eastern NV. However, such conditions are expected to remain sufficiently localized to preclude highlights. ..Moore.. 08/11/2024 .PREV DISCUSSION... /ISSUED 1255 AM CDT Sun Aug 11 2024/ ...Synopsis... A belt of stronger mid-level winds will be present on the poleward side of a flattened upper-level ridge in the southern U.S. With time, a shortwave trough will amplify and move into northern California and the northwest Great Basin. At the surface, the pressure pattern will be rather disorganized until stronger pressure falls occur in the Northwest late in the period. Fire weather concerns are expected to be low for most areas today. Some locally elevated conditions are possible in parts of central/northern Nevada. RH will likely be in the 10-15% range, but winds will be light. The potential for thunderstorms over sufficiently dry fuels is also too low for highlights. ...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 1113 AM CDT Sun Aug 11 2024 Valid 111700Z - 121200Z ...NO CRITICAL AREAS... A pair of isolated dry-thunderstorm risk areas have been introduced for this morning's forecast update. 12 UTC soundings from BOI and OTX sampled relatively dry low-level conditions and PWAT values similar to previous days that have seen a mixture of wet and dry thunderstorms. MRMS rainfall estimates and surface observations suggest that most locations have not received wetting rainfall over the past 48 hours with several lightning-caused fire starts have been reported during this period. Morning HREF guidance shows a signal for isolated convection this afternoon and early Tuesday morning with favorable thermodynamic profiles in place for a mixture of wet/dry thunderstorms. Given recent observations, the model signals, and antecedent fuel conditions, risk highlights appear warranted. Localized elevated conditions remain likely across west-central NV in the immediate lee of the northern Sierra Nevada as well as across portions of eastern NV. However, such conditions are expected to remain sufficiently localized to preclude highlights. ..Moore.. 08/11/2024 .PREV DISCUSSION... /ISSUED 1255 AM CDT Sun Aug 11 2024/ ...Synopsis... A belt of stronger mid-level winds will be present on the poleward side of a flattened upper-level ridge in the southern U.S. With time, a shortwave trough will amplify and move into northern California and the northwest Great Basin. At the surface, the pressure pattern will be rather disorganized until stronger pressure falls occur in the Northwest late in the period. Fire weather concerns are expected to be low for most areas today. Some locally elevated conditions are possible in parts of central/northern Nevada. RH will likely be in the 10-15% range, but winds will be light. The potential for thunderstorms over sufficiently dry fuels is also too low for highlights. ...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 1113 AM CDT Sun Aug 11 2024 Valid 111700Z - 121200Z ...NO CRITICAL AREAS... A pair of isolated dry-thunderstorm risk areas have been introduced for this morning's forecast update. 12 UTC soundings from BOI and OTX sampled relatively dry low-level conditions and PWAT values similar to previous days that have seen a mixture of wet and dry thunderstorms. MRMS rainfall estimates and surface observations suggest that most locations have not received wetting rainfall over the past 48 hours with several lightning-caused fire starts have been reported during this period. Morning HREF guidance shows a signal for isolated convection this afternoon and early Tuesday morning with favorable thermodynamic profiles in place for a mixture of wet/dry thunderstorms. Given recent observations, the model signals, and antecedent fuel conditions, risk highlights appear warranted. Localized elevated conditions remain likely across west-central NV in the immediate lee of the northern Sierra Nevada as well as across portions of eastern NV. However, such conditions are expected to remain sufficiently localized to preclude highlights. ..Moore.. 08/11/2024 .PREV DISCUSSION... /ISSUED 1255 AM CDT Sun Aug 11 2024/ ...Synopsis... A belt of stronger mid-level winds will be present on the poleward side of a flattened upper-level ridge in the southern U.S. With time, a shortwave trough will amplify and move into northern California and the northwest Great Basin. At the surface, the pressure pattern will be rather disorganized until stronger pressure falls occur in the Northwest late in the period. Fire weather concerns are expected to be low for most areas today. Some locally elevated conditions are possible in parts of central/northern Nevada. RH will likely be in the 10-15% range, but winds will be light. The potential for thunderstorms over sufficiently dry fuels is also too low for highlights. ...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 1113 AM CDT Sun Aug 11 2024 Valid 111700Z - 121200Z ...NO CRITICAL AREAS... A pair of isolated dry-thunderstorm risk areas have been introduced for this morning's forecast update. 12 UTC soundings from BOI and OTX sampled relatively dry low-level conditions and PWAT values similar to previous days that have seen a mixture of wet and dry thunderstorms. MRMS rainfall estimates and surface observations suggest that most locations have not received wetting rainfall over the past 48 hours with several lightning-caused fire starts have been reported during this period. Morning HREF guidance shows a signal for isolated convection this afternoon and early Tuesday morning with favorable thermodynamic profiles in place for a mixture of wet/dry thunderstorms. Given recent observations, the model signals, and antecedent fuel conditions, risk highlights appear warranted. Localized elevated conditions remain likely across west-central NV in the immediate lee of the northern Sierra Nevada as well as across portions of eastern NV. However, such conditions are expected to remain sufficiently localized to preclude highlights. ..Moore.. 08/11/2024 .PREV DISCUSSION... /ISSUED 1255 AM CDT Sun Aug 11 2024/ ...Synopsis... A belt of stronger mid-level winds will be present on the poleward side of a flattened upper-level ridge in the southern U.S. With time, a shortwave trough will amplify and move into northern California and the northwest Great Basin. At the surface, the pressure pattern will be rather disorganized until stronger pressure falls occur in the Northwest late in the period. Fire weather concerns are expected to be low for most areas today. Some locally elevated conditions are possible in parts of central/northern Nevada. RH will likely be in the 10-15% range, but winds will be light. The potential for thunderstorms over sufficiently dry fuels is also too low for highlights. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0742 AM CDT Sun Aug 11 2024 Valid 111300Z - 121200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR WESTERN NEBRASKA INTO NORTHEAST COLORADO AND NORTHWEST KANSAS... ...SUMMARY... Scattered severe thunderstorms are possible across parts of the central High Plains this afternoon into the early evening. ...Central High Plains to Black Hills... Water-vapor imagery shows a potent mid-level shortwave trough moving east across southern MT/WY this morning. This upper feature is forecast to reach the Black Hills by early to mid afternoon and subsequently move into the IA/MO vicinity by early Monday morning. At the surface, dominant high pressure will hold across the mid MS Valley such that southeasterly low-level trajectories will be maintained across the central High Plains. Morning raob data over the lower MO Valley into eastern NE/KS sampled a relatively cool/stable continental airmass. Appreciable destabilization will occur in the vicinity of a lee trough where stronger heating is forecast today. Some isolated thunderstorms will likely shift eastward from MT/WY into the SD/NE Panhandle vicinity by early afternoon with additional storm development likely as stronger large-scale ascent impinges on the instability axis over the High Plains. Forecast soundings show long, straight hodographs which will promote supercellular organization with the stronger updrafts. Widely scattered to scattered storms are possible from the Black Hills southward into eastern CO/northwest KS. Large hail and severe gusts will be the primary hazards with the stronger storms before this activity moves east and/or weakens by mid evening related to the loss of heating. ...Raton Mesa east into the TX Panhandle and western OK... A reservoir of greater moisture/buoyancy will exist with east extent as a modifying outflow boundary becomes draped across the region this afternoon in wake of morning storms over central OK. An MCV noted in radar imagery this morning will move east across northern OK through the early afternoon with implied subsidence in its wake. Little in the way of large-scale forcing for ascent will contribute to suppressing convective development through mid afternoon. However, heating over the Raton Mesa and TX Panhandle may foster isolated storms late this afternoon into the early evening. More uncertain is if a couple of storms can develop farther east into OK where large buoyancy (3000+ J/kg MLCAPE) is forecast with a weak cap. Model guidance varies considerably (as expected with a wide array of potential solutions) but mesoscale trends will be monitored for the possible inclusion of low-severe probabilities if uncertainty decreases. ..Smith/Jewell.. 08/11/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0742 AM CDT Sun Aug 11 2024 Valid 111300Z - 121200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR WESTERN NEBRASKA INTO NORTHEAST COLORADO AND NORTHWEST KANSAS... ...SUMMARY... Scattered severe thunderstorms are possible across parts of the central High Plains this afternoon into the early evening. ...Central High Plains to Black Hills... Water-vapor imagery shows a potent mid-level shortwave trough moving east across southern MT/WY this morning. This upper feature is forecast to reach the Black Hills by early to mid afternoon and subsequently move into the IA/MO vicinity by early Monday morning. At the surface, dominant high pressure will hold across the mid MS Valley such that southeasterly low-level trajectories will be maintained across the central High Plains. Morning raob data over the lower MO Valley into eastern NE/KS sampled a relatively cool/stable continental airmass. Appreciable destabilization will occur in the vicinity of a lee trough where stronger heating is forecast today. Some isolated thunderstorms will likely shift eastward from MT/WY into the SD/NE Panhandle vicinity by early afternoon with additional storm development likely as stronger large-scale ascent impinges on the instability axis over the High Plains. Forecast soundings show long, straight hodographs which will promote supercellular organization with the stronger updrafts. Widely scattered to scattered storms are possible from the Black Hills southward into eastern CO/northwest KS. Large hail and severe gusts will be the primary hazards with the stronger storms before this activity moves east and/or weakens by mid evening related to the loss of heating. ...Raton Mesa east into the TX Panhandle and western OK... A reservoir of greater moisture/buoyancy will exist with east extent as a modifying outflow boundary becomes draped across the region this afternoon in wake of morning storms over central OK. An MCV noted in radar imagery this morning will move east across northern OK through the early afternoon with implied subsidence in its wake. Little in the way of large-scale forcing for ascent will contribute to suppressing convective development through mid afternoon. However, heating over the Raton Mesa and TX Panhandle may foster isolated storms late this afternoon into the early evening. More uncertain is if a couple of storms can develop farther east into OK where large buoyancy (3000+ J/kg MLCAPE) is forecast with a weak cap. Model guidance varies considerably (as expected with a wide array of potential solutions) but mesoscale trends will be monitored for the possible inclusion of low-severe probabilities if uncertainty decreases. ..Smith/Jewell.. 08/11/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0742 AM CDT Sun Aug 11 2024 Valid 111300Z - 121200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR WESTERN NEBRASKA INTO NORTHEAST COLORADO AND NORTHWEST KANSAS... ...SUMMARY... Scattered severe thunderstorms are possible across parts of the central High Plains this afternoon into the early evening. ...Central High Plains to Black Hills... Water-vapor imagery shows a potent mid-level shortwave trough moving east across southern MT/WY this morning. This upper feature is forecast to reach the Black Hills by early to mid afternoon and subsequently move into the IA/MO vicinity by early Monday morning. At the surface, dominant high pressure will hold across the mid MS Valley such that southeasterly low-level trajectories will be maintained across the central High Plains. Morning raob data over the lower MO Valley into eastern NE/KS sampled a relatively cool/stable continental airmass. Appreciable destabilization will occur in the vicinity of a lee trough where stronger heating is forecast today. Some isolated thunderstorms will likely shift eastward from MT/WY into the SD/NE Panhandle vicinity by early afternoon with additional storm development likely as stronger large-scale ascent impinges on the instability axis over the High Plains. Forecast soundings show long, straight hodographs which will promote supercellular organization with the stronger updrafts. Widely scattered to scattered storms are possible from the Black Hills southward into eastern CO/northwest KS. Large hail and severe gusts will be the primary hazards with the stronger storms before this activity moves east and/or weakens by mid evening related to the loss of heating. ...Raton Mesa east into the TX Panhandle and western OK... A reservoir of greater moisture/buoyancy will exist with east extent as a modifying outflow boundary becomes draped across the region this afternoon in wake of morning storms over central OK. An MCV noted in radar imagery this morning will move east across northern OK through the early afternoon with implied subsidence in its wake. Little in the way of large-scale forcing for ascent will contribute to suppressing convective development through mid afternoon. However, heating over the Raton Mesa and TX Panhandle may foster isolated storms late this afternoon into the early evening. More uncertain is if a couple of storms can develop farther east into OK where large buoyancy (3000+ J/kg MLCAPE) is forecast with a weak cap. Model guidance varies considerably (as expected with a wide array of potential solutions) but mesoscale trends will be monitored for the possible inclusion of low-severe probabilities if uncertainty decreases. ..Smith/Jewell.. 08/11/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0742 AM CDT Sun Aug 11 2024 Valid 111300Z - 121200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR WESTERN NEBRASKA INTO NORTHEAST COLORADO AND NORTHWEST KANSAS... ...SUMMARY... Scattered severe thunderstorms are possible across parts of the central High Plains this afternoon into the early evening. ...Central High Plains to Black Hills... Water-vapor imagery shows a potent mid-level shortwave trough moving east across southern MT/WY this morning. This upper feature is forecast to reach the Black Hills by early to mid afternoon and subsequently move into the IA/MO vicinity by early Monday morning. At the surface, dominant high pressure will hold across the mid MS Valley such that southeasterly low-level trajectories will be maintained across the central High Plains. Morning raob data over the lower MO Valley into eastern NE/KS sampled a relatively cool/stable continental airmass. Appreciable destabilization will occur in the vicinity of a lee trough where stronger heating is forecast today. Some isolated thunderstorms will likely shift eastward from MT/WY into the SD/NE Panhandle vicinity by early afternoon with additional storm development likely as stronger large-scale ascent impinges on the instability axis over the High Plains. Forecast soundings show long, straight hodographs which will promote supercellular organization with the stronger updrafts. Widely scattered to scattered storms are possible from the Black Hills southward into eastern CO/northwest KS. Large hail and severe gusts will be the primary hazards with the stronger storms before this activity moves east and/or weakens by mid evening related to the loss of heating. ...Raton Mesa east into the TX Panhandle and western OK... A reservoir of greater moisture/buoyancy will exist with east extent as a modifying outflow boundary becomes draped across the region this afternoon in wake of morning storms over central OK. An MCV noted in radar imagery this morning will move east across northern OK through the early afternoon with implied subsidence in its wake. Little in the way of large-scale forcing for ascent will contribute to suppressing convective development through mid afternoon. However, heating over the Raton Mesa and TX Panhandle may foster isolated storms late this afternoon into the early evening. More uncertain is if a couple of storms can develop farther east into OK where large buoyancy (3000+ J/kg MLCAPE) is forecast with a weak cap. Model guidance varies considerably (as expected with a wide array of potential solutions) but mesoscale trends will be monitored for the possible inclusion of low-severe probabilities if uncertainty decreases. ..Smith/Jewell.. 08/11/2024 Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0348 AM CDT Sun Aug 11 2024 Valid 141200Z - 191200Z ...DISCUSSION... Multiple mid-level perturbations should move eastward across the northern/central CONUS from the middle of this week through next weekend. This should generally act to suppress upper ridging to the southern states through at least Day 5/Thursday. Low predictability for organized severe potential remains apparent in this flow regime given the low-amplitude nature of relevant features. But, medium-range guidance shows a tendency for a more amplified pattern by late week into the upcoming weekend as an upper trough/low potentially develops across the western states, ridging builds over the central CONUS, and a separate upper trough/low remains over the eastern CONUS. Regardless of these developments, isolated severe potential may exist on Day 4/Wednesday across parts of the northern/central Plains and perhaps Upper Midwest in association with one of the mid-level perturbations. Some threat for organized severe thunderstorms will probably continue each day through the extended forecast period across parts of the Plains into the Midwest and vicinity, although delineating regions of greater potential remains highly uncertain. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0348 AM CDT Sun Aug 11 2024 Valid 141200Z - 191200Z ...DISCUSSION... Multiple mid-level perturbations should move eastward across the northern/central CONUS from the middle of this week through next weekend. This should generally act to suppress upper ridging to the southern states through at least Day 5/Thursday. Low predictability for organized severe potential remains apparent in this flow regime given the low-amplitude nature of relevant features. But, medium-range guidance shows a tendency for a more amplified pattern by late week into the upcoming weekend as an upper trough/low potentially develops across the western states, ridging builds over the central CONUS, and a separate upper trough/low remains over the eastern CONUS. Regardless of these developments, isolated severe potential may exist on Day 4/Wednesday across parts of the northern/central Plains and perhaps Upper Midwest in association with one of the mid-level perturbations. Some threat for organized severe thunderstorms will probably continue each day through the extended forecast period across parts of the Plains into the Midwest and vicinity, although delineating regions of greater potential remains highly uncertain. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0348 AM CDT Sun Aug 11 2024 Valid 141200Z - 191200Z ...DISCUSSION... Multiple mid-level perturbations should move eastward across the northern/central CONUS from the middle of this week through next weekend. This should generally act to suppress upper ridging to the southern states through at least Day 5/Thursday. Low predictability for organized severe potential remains apparent in this flow regime given the low-amplitude nature of relevant features. But, medium-range guidance shows a tendency for a more amplified pattern by late week into the upcoming weekend as an upper trough/low potentially develops across the western states, ridging builds over the central CONUS, and a separate upper trough/low remains over the eastern CONUS. Regardless of these developments, isolated severe potential may exist on Day 4/Wednesday across parts of the northern/central Plains and perhaps Upper Midwest in association with one of the mid-level perturbations. Some threat for organized severe thunderstorms will probably continue each day through the extended forecast period across parts of the Plains into the Midwest and vicinity, although delineating regions of greater potential remains highly uncertain. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0348 AM CDT Sun Aug 11 2024 Valid 141200Z - 191200Z ...DISCUSSION... Multiple mid-level perturbations should move eastward across the northern/central CONUS from the middle of this week through next weekend. This should generally act to suppress upper ridging to the southern states through at least Day 5/Thursday. Low predictability for organized severe potential remains apparent in this flow regime given the low-amplitude nature of relevant features. But, medium-range guidance shows a tendency for a more amplified pattern by late week into the upcoming weekend as an upper trough/low potentially develops across the western states, ridging builds over the central CONUS, and a separate upper trough/low remains over the eastern CONUS. Regardless of these developments, isolated severe potential may exist on Day 4/Wednesday across parts of the northern/central Plains and perhaps Upper Midwest in association with one of the mid-level perturbations. Some threat for organized severe thunderstorms will probably continue each day through the extended forecast period across parts of the Plains into the Midwest and vicinity, although delineating regions of greater potential remains highly uncertain. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0348 AM CDT Sun Aug 11 2024 Valid 141200Z - 191200Z ...DISCUSSION... Multiple mid-level perturbations should move eastward across the northern/central CONUS from the middle of this week through next weekend. This should generally act to suppress upper ridging to the southern states through at least Day 5/Thursday. Low predictability for organized severe potential remains apparent in this flow regime given the low-amplitude nature of relevant features. But, medium-range guidance shows a tendency for a more amplified pattern by late week into the upcoming weekend as an upper trough/low potentially develops across the western states, ridging builds over the central CONUS, and a separate upper trough/low remains over the eastern CONUS. Regardless of these developments, isolated severe potential may exist on Day 4/Wednesday across parts of the northern/central Plains and perhaps Upper Midwest in association with one of the mid-level perturbations. Some threat for organized severe thunderstorms will probably continue each day through the extended forecast period across parts of the Plains into the Midwest and vicinity, although delineating regions of greater potential remains highly uncertain. Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0228 AM CDT Sun Aug 11 2024 Valid 131200Z - 141200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL HIGH PLAINS... ...SUMMARY... Isolated severe thunderstorms appear possible Tuesday across parts of the northern/central High Plains. ...Northern/Central High Plains... Upper ridging should remain prevalent over much of the Plains on Tuesday, while a mid-level shortwave trough is forecast to develop northeastward from the interior Pacific Northwest across the northern Rockies and adjacent High Plains. Modest low-level mass response ahead of this shortwave trough should encourage the development/sharpening of a weak surface low and associated lee trough extending southward along much of the length of the northern/central High Plains. Some northward advance of low-level moisture is expected across these areas, along and east of the lee trough. Steepened mid-level lapse rates and daytime heating of this moistening airmass should support moderate instability developing by late Tuesday afternoon. Although mid-level flow is not forecast to be overly strong in association with the mid-level shortwave trough, gradual veering and modest strengthening of the wind field with height through mid/upper levels should foster sufficient deep-layer shear for some thunderstorm organization. An isolated threat for hail and severe winds should exist with any robust cores that can develop along the length of the lee trough and subsequently spread eastward Tuesday afternoon through evening. Have therefore included a fairly broad Marginal Risk across parts of the northern/central High Plains to account for this potential. ...Carolinas... As a mid/upper-level trough persists over the eastern states, some enhancement to west-northwesterly winds is forecast across parts of the OH/TN Valleys into the Carolinas and Southeast on Tuesday. While deep-layer shear appears conditionally supportive of organized convection, poor lapse rates and limited instability may tend to hinder more robust thunderstorms from developing across SC and vicinity Tuesday afternoon. Still, occasional strong/gusty winds appear possible, but the overall severe threat currently appears too limited to include any probabilities. ..Gleason.. 08/11/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0228 AM CDT Sun Aug 11 2024 Valid 131200Z - 141200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL HIGH PLAINS... ...SUMMARY... Isolated severe thunderstorms appear possible Tuesday across parts of the northern/central High Plains. ...Northern/Central High Plains... Upper ridging should remain prevalent over much of the Plains on Tuesday, while a mid-level shortwave trough is forecast to develop northeastward from the interior Pacific Northwest across the northern Rockies and adjacent High Plains. Modest low-level mass response ahead of this shortwave trough should encourage the development/sharpening of a weak surface low and associated lee trough extending southward along much of the length of the northern/central High Plains. Some northward advance of low-level moisture is expected across these areas, along and east of the lee trough. Steepened mid-level lapse rates and daytime heating of this moistening airmass should support moderate instability developing by late Tuesday afternoon. Although mid-level flow is not forecast to be overly strong in association with the mid-level shortwave trough, gradual veering and modest strengthening of the wind field with height through mid/upper levels should foster sufficient deep-layer shear for some thunderstorm organization. An isolated threat for hail and severe winds should exist with any robust cores that can develop along the length of the lee trough and subsequently spread eastward Tuesday afternoon through evening. Have therefore included a fairly broad Marginal Risk across parts of the northern/central High Plains to account for this potential. ...Carolinas... As a mid/upper-level trough persists over the eastern states, some enhancement to west-northwesterly winds is forecast across parts of the OH/TN Valleys into the Carolinas and Southeast on Tuesday. While deep-layer shear appears conditionally supportive of organized convection, poor lapse rates and limited instability may tend to hinder more robust thunderstorms from developing across SC and vicinity Tuesday afternoon. Still, occasional strong/gusty winds appear possible, but the overall severe threat currently appears too limited to include any probabilities. ..Gleason.. 08/11/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0228 AM CDT Sun Aug 11 2024 Valid 131200Z - 141200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL HIGH PLAINS... ...SUMMARY... Isolated severe thunderstorms appear possible Tuesday across parts of the northern/central High Plains. ...Northern/Central High Plains... Upper ridging should remain prevalent over much of the Plains on Tuesday, while a mid-level shortwave trough is forecast to develop northeastward from the interior Pacific Northwest across the northern Rockies and adjacent High Plains. Modest low-level mass response ahead of this shortwave trough should encourage the development/sharpening of a weak surface low and associated lee trough extending southward along much of the length of the northern/central High Plains. Some northward advance of low-level moisture is expected across these areas, along and east of the lee trough. Steepened mid-level lapse rates and daytime heating of this moistening airmass should support moderate instability developing by late Tuesday afternoon. Although mid-level flow is not forecast to be overly strong in association with the mid-level shortwave trough, gradual veering and modest strengthening of the wind field with height through mid/upper levels should foster sufficient deep-layer shear for some thunderstorm organization. An isolated threat for hail and severe winds should exist with any robust cores that can develop along the length of the lee trough and subsequently spread eastward Tuesday afternoon through evening. Have therefore included a fairly broad Marginal Risk across parts of the northern/central High Plains to account for this potential. ...Carolinas... As a mid/upper-level trough persists over the eastern states, some enhancement to west-northwesterly winds is forecast across parts of the OH/TN Valleys into the Carolinas and Southeast on Tuesday. While deep-layer shear appears conditionally supportive of organized convection, poor lapse rates and limited instability may tend to hinder more robust thunderstorms from developing across SC and vicinity Tuesday afternoon. Still, occasional strong/gusty winds appear possible, but the overall severe threat currently appears too limited to include any probabilities. ..Gleason.. 08/11/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0228 AM CDT Sun Aug 11 2024 Valid 131200Z - 141200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL HIGH PLAINS... ...SUMMARY... Isolated severe thunderstorms appear possible Tuesday across parts of the northern/central High Plains. ...Northern/Central High Plains... Upper ridging should remain prevalent over much of the Plains on Tuesday, while a mid-level shortwave trough is forecast to develop northeastward from the interior Pacific Northwest across the northern Rockies and adjacent High Plains. Modest low-level mass response ahead of this shortwave trough should encourage the development/sharpening of a weak surface low and associated lee trough extending southward along much of the length of the northern/central High Plains. Some northward advance of low-level moisture is expected across these areas, along and east of the lee trough. Steepened mid-level lapse rates and daytime heating of this moistening airmass should support moderate instability developing by late Tuesday afternoon. Although mid-level flow is not forecast to be overly strong in association with the mid-level shortwave trough, gradual veering and modest strengthening of the wind field with height through mid/upper levels should foster sufficient deep-layer shear for some thunderstorm organization. An isolated threat for hail and severe winds should exist with any robust cores that can develop along the length of the lee trough and subsequently spread eastward Tuesday afternoon through evening. Have therefore included a fairly broad Marginal Risk across parts of the northern/central High Plains to account for this potential. ...Carolinas... As a mid/upper-level trough persists over the eastern states, some enhancement to west-northwesterly winds is forecast across parts of the OH/TN Valleys into the Carolinas and Southeast on Tuesday. While deep-layer shear appears conditionally supportive of organized convection, poor lapse rates and limited instability may tend to hinder more robust thunderstorms from developing across SC and vicinity Tuesday afternoon. Still, occasional strong/gusty winds appear possible, but the overall severe threat currently appears too limited to include any probabilities. ..Gleason.. 08/11/2024 Read more