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SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0201 AM CDT Sun Aug 03 2025 Valid 031200Z - 041200Z ...Synopsis... A midlevel trough will move eastward from the eastern Pacific into the Northwest through the period. Within the base of the trough, enhanced midlevel westerly flow will overspread a dry/deeply mixed boundary layer across the Great Basin during the afternoon. This will favor breezy/gusty surface winds (around 15-20 mph) amid single-digit to lower teens RH, and given receptive fuels, elevated fire-weather conditions are expected. Preceding the trough, forcing for ascent will aid in afternoon thunderstorm development across the northern Great Basin and Intermountain West. Across parts of northern CA, southeastern OR, and southwestern ID, inverted-V soundings (around 0.5-0.7 inch PW) and quick storm motions will lead to mostly dry thunderstorms. These storms will pose a risk of lightning-induced ignitions and strong-severe outflow winds. For details on the severe-storm risk, see the SPC Day 1 Convective Outlook. A mix of wet/dry thunderstorms (with higher storms coverage) are also expected farther north across east-central OR, though these storms should be accompanied by measurable rainfall. Lightning-induced ignitions will still be possible along the peripheries of rain cores. ..Weinman.. 08/03/2025 ...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 0201 AM CDT Sun Aug 03 2025 Valid 031200Z - 041200Z ...Synopsis... A midlevel trough will move eastward from the eastern Pacific into the Northwest through the period. Within the base of the trough, enhanced midlevel westerly flow will overspread a dry/deeply mixed boundary layer across the Great Basin during the afternoon. This will favor breezy/gusty surface winds (around 15-20 mph) amid single-digit to lower teens RH, and given receptive fuels, elevated fire-weather conditions are expected. Preceding the trough, forcing for ascent will aid in afternoon thunderstorm development across the northern Great Basin and Intermountain West. Across parts of northern CA, southeastern OR, and southwestern ID, inverted-V soundings (around 0.5-0.7 inch PW) and quick storm motions will lead to mostly dry thunderstorms. These storms will pose a risk of lightning-induced ignitions and strong-severe outflow winds. For details on the severe-storm risk, see the SPC Day 1 Convective Outlook. A mix of wet/dry thunderstorms (with higher storms coverage) are also expected farther north across east-central OR, though these storms should be accompanied by measurable rainfall. Lightning-induced ignitions will still be possible along the peripheries of rain cores. ..Weinman.. 08/03/2025 ...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 0201 AM CDT Sun Aug 03 2025 Valid 031200Z - 041200Z ...Synopsis... A midlevel trough will move eastward from the eastern Pacific into the Northwest through the period. Within the base of the trough, enhanced midlevel westerly flow will overspread a dry/deeply mixed boundary layer across the Great Basin during the afternoon. This will favor breezy/gusty surface winds (around 15-20 mph) amid single-digit to lower teens RH, and given receptive fuels, elevated fire-weather conditions are expected. Preceding the trough, forcing for ascent will aid in afternoon thunderstorm development across the northern Great Basin and Intermountain West. Across parts of northern CA, southeastern OR, and southwestern ID, inverted-V soundings (around 0.5-0.7 inch PW) and quick storm motions will lead to mostly dry thunderstorms. These storms will pose a risk of lightning-induced ignitions and strong-severe outflow winds. For details on the severe-storm risk, see the SPC Day 1 Convective Outlook. A mix of wet/dry thunderstorms (with higher storms coverage) are also expected farther north across east-central OR, though these storms should be accompanied by measurable rainfall. Lightning-induced ignitions will still be possible along the peripheries of rain cores. ..Weinman.. 08/03/2025 ...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 0201 AM CDT Sun Aug 03 2025 Valid 031200Z - 041200Z ...Synopsis... A midlevel trough will move eastward from the eastern Pacific into the Northwest through the period. Within the base of the trough, enhanced midlevel westerly flow will overspread a dry/deeply mixed boundary layer across the Great Basin during the afternoon. This will favor breezy/gusty surface winds (around 15-20 mph) amid single-digit to lower teens RH, and given receptive fuels, elevated fire-weather conditions are expected. Preceding the trough, forcing for ascent will aid in afternoon thunderstorm development across the northern Great Basin and Intermountain West. Across parts of northern CA, southeastern OR, and southwestern ID, inverted-V soundings (around 0.5-0.7 inch PW) and quick storm motions will lead to mostly dry thunderstorms. These storms will pose a risk of lightning-induced ignitions and strong-severe outflow winds. For details on the severe-storm risk, see the SPC Day 1 Convective Outlook. A mix of wet/dry thunderstorms (with higher storms coverage) are also expected farther north across east-central OR, though these storms should be accompanied by measurable rainfall. Lightning-induced ignitions will still be possible along the peripheries of rain cores. ..Weinman.. 08/03/2025 ...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 1259 AM CDT Sun Aug 03 2025 Valid 041200Z - 051200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM PARTS OF THE NORTHERN ROCKIES INTO THE CENTRAL AND NORTHERN PLAINS... ...SUMMARY... Isolated thunderstorms with severe gusts and hail will be possible on Monday from parts of the northern Rockies into the Dakotas and central High Plains. ...Northern Rockies/Northern High Plains... A mid-level shortwave trough will move northeastward across the Pacific Northwest on Monday. At the surface, a cold front will advance eastward into the northern Rockies, as upslope easterly flow remains over the northern High Plains. As surface temperatures warm, thunderstorm development is expected during the afternoon near the front, and in the higher terrain of the northern Rockies. These storms will likely increase in coverage by early evening, moving eastward into the northern High Plains. Surface dewpoints across much central and eastern Montana are forecast to be in the upper 40s and lower 50s F, which will contribute to the development of weak instability by afternoon. Near the forecast pocket of instability, forecast soundings suggest that 0-6 km shear will be in the 30 to 40 knot range. This, combined with steep low to mid-level lapse rates near 8 C/km, will likely support an localized severe threat. The stronger rotating cells could produce hail. Isolated severe gusts will also be possible, mainly with short line segments that have some organization. ...Central and Northern Plains... A mid-level ridge will remain over the central Rockies on Monday, as a trough remains nearly stationary across northern Minnesota. At the surface, a north-to-south corridor of low-level moisture with dewpoints in the 60s F, will be in place from central Kansas northward into the eastern Dakotas. Moderate instability is forecast to develop along the western edge of this moist airmass, from western Nebraska into southwestern and central South Dakota. As destabilization takes place during the day, isolated thunderstorm development will be possible, mainly in areas where low-level convergence becomes maximized. Across much of the region, 0-6 km shear is forecast to be in the 35 to 45 knot range. This will support an isolated threat for severe gusts. Hail will also be possible in the central High Plains, where mid-level lapse rates are forecast to be steep. ..Broyles.. 08/03/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1259 AM CDT Sun Aug 03 2025 Valid 041200Z - 051200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM PARTS OF THE NORTHERN ROCKIES INTO THE CENTRAL AND NORTHERN PLAINS... ...SUMMARY... Isolated thunderstorms with severe gusts and hail will be possible on Monday from parts of the northern Rockies into the Dakotas and central High Plains. ...Northern Rockies/Northern High Plains... A mid-level shortwave trough will move northeastward across the Pacific Northwest on Monday. At the surface, a cold front will advance eastward into the northern Rockies, as upslope easterly flow remains over the northern High Plains. As surface temperatures warm, thunderstorm development is expected during the afternoon near the front, and in the higher terrain of the northern Rockies. These storms will likely increase in coverage by early evening, moving eastward into the northern High Plains. Surface dewpoints across much central and eastern Montana are forecast to be in the upper 40s and lower 50s F, which will contribute to the development of weak instability by afternoon. Near the forecast pocket of instability, forecast soundings suggest that 0-6 km shear will be in the 30 to 40 knot range. This, combined with steep low to mid-level lapse rates near 8 C/km, will likely support an localized severe threat. The stronger rotating cells could produce hail. Isolated severe gusts will also be possible, mainly with short line segments that have some organization. ...Central and Northern Plains... A mid-level ridge will remain over the central Rockies on Monday, as a trough remains nearly stationary across northern Minnesota. At the surface, a north-to-south corridor of low-level moisture with dewpoints in the 60s F, will be in place from central Kansas northward into the eastern Dakotas. Moderate instability is forecast to develop along the western edge of this moist airmass, from western Nebraska into southwestern and central South Dakota. As destabilization takes place during the day, isolated thunderstorm development will be possible, mainly in areas where low-level convergence becomes maximized. Across much of the region, 0-6 km shear is forecast to be in the 35 to 45 knot range. This will support an isolated threat for severe gusts. Hail will also be possible in the central High Plains, where mid-level lapse rates are forecast to be steep. ..Broyles.. 08/03/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1259 AM CDT Sun Aug 03 2025 Valid 041200Z - 051200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM PARTS OF THE NORTHERN ROCKIES INTO THE CENTRAL AND NORTHERN PLAINS... ...SUMMARY... Isolated thunderstorms with severe gusts and hail will be possible on Monday from parts of the northern Rockies into the Dakotas and central High Plains. ...Northern Rockies/Northern High Plains... A mid-level shortwave trough will move northeastward across the Pacific Northwest on Monday. At the surface, a cold front will advance eastward into the northern Rockies, as upslope easterly flow remains over the northern High Plains. As surface temperatures warm, thunderstorm development is expected during the afternoon near the front, and in the higher terrain of the northern Rockies. These storms will likely increase in coverage by early evening, moving eastward into the northern High Plains. Surface dewpoints across much central and eastern Montana are forecast to be in the upper 40s and lower 50s F, which will contribute to the development of weak instability by afternoon. Near the forecast pocket of instability, forecast soundings suggest that 0-6 km shear will be in the 30 to 40 knot range. This, combined with steep low to mid-level lapse rates near 8 C/km, will likely support an localized severe threat. The stronger rotating cells could produce hail. Isolated severe gusts will also be possible, mainly with short line segments that have some organization. ...Central and Northern Plains... A mid-level ridge will remain over the central Rockies on Monday, as a trough remains nearly stationary across northern Minnesota. At the surface, a north-to-south corridor of low-level moisture with dewpoints in the 60s F, will be in place from central Kansas northward into the eastern Dakotas. Moderate instability is forecast to develop along the western edge of this moist airmass, from western Nebraska into southwestern and central South Dakota. As destabilization takes place during the day, isolated thunderstorm development will be possible, mainly in areas where low-level convergence becomes maximized. Across much of the region, 0-6 km shear is forecast to be in the 35 to 45 knot range. This will support an isolated threat for severe gusts. Hail will also be possible in the central High Plains, where mid-level lapse rates are forecast to be steep. ..Broyles.. 08/03/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1259 AM CDT Sun Aug 03 2025 Valid 041200Z - 051200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM PARTS OF THE NORTHERN ROCKIES INTO THE CENTRAL AND NORTHERN PLAINS... ...SUMMARY... Isolated thunderstorms with severe gusts and hail will be possible on Monday from parts of the northern Rockies into the Dakotas and central High Plains. ...Northern Rockies/Northern High Plains... A mid-level shortwave trough will move northeastward across the Pacific Northwest on Monday. At the surface, a cold front will advance eastward into the northern Rockies, as upslope easterly flow remains over the northern High Plains. As surface temperatures warm, thunderstorm development is expected during the afternoon near the front, and in the higher terrain of the northern Rockies. These storms will likely increase in coverage by early evening, moving eastward into the northern High Plains. Surface dewpoints across much central and eastern Montana are forecast to be in the upper 40s and lower 50s F, which will contribute to the development of weak instability by afternoon. Near the forecast pocket of instability, forecast soundings suggest that 0-6 km shear will be in the 30 to 40 knot range. This, combined with steep low to mid-level lapse rates near 8 C/km, will likely support an localized severe threat. The stronger rotating cells could produce hail. Isolated severe gusts will also be possible, mainly with short line segments that have some organization. ...Central and Northern Plains... A mid-level ridge will remain over the central Rockies on Monday, as a trough remains nearly stationary across northern Minnesota. At the surface, a north-to-south corridor of low-level moisture with dewpoints in the 60s F, will be in place from central Kansas northward into the eastern Dakotas. Moderate instability is forecast to develop along the western edge of this moist airmass, from western Nebraska into southwestern and central South Dakota. As destabilization takes place during the day, isolated thunderstorm development will be possible, mainly in areas where low-level convergence becomes maximized. Across much of the region, 0-6 km shear is forecast to be in the 35 to 45 knot range. This will support an isolated threat for severe gusts. Hail will also be possible in the central High Plains, where mid-level lapse rates are forecast to be steep. ..Broyles.. 08/03/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1259 AM CDT Sun Aug 03 2025 Valid 041200Z - 051200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM PARTS OF THE NORTHERN ROCKIES INTO THE CENTRAL AND NORTHERN PLAINS... ...SUMMARY... Isolated thunderstorms with severe gusts and hail will be possible on Monday from parts of the northern Rockies into the Dakotas and central High Plains. ...Northern Rockies/Northern High Plains... A mid-level shortwave trough will move northeastward across the Pacific Northwest on Monday. At the surface, a cold front will advance eastward into the northern Rockies, as upslope easterly flow remains over the northern High Plains. As surface temperatures warm, thunderstorm development is expected during the afternoon near the front, and in the higher terrain of the northern Rockies. These storms will likely increase in coverage by early evening, moving eastward into the northern High Plains. Surface dewpoints across much central and eastern Montana are forecast to be in the upper 40s and lower 50s F, which will contribute to the development of weak instability by afternoon. Near the forecast pocket of instability, forecast soundings suggest that 0-6 km shear will be in the 30 to 40 knot range. This, combined with steep low to mid-level lapse rates near 8 C/km, will likely support an localized severe threat. The stronger rotating cells could produce hail. Isolated severe gusts will also be possible, mainly with short line segments that have some organization. ...Central and Northern Plains... A mid-level ridge will remain over the central Rockies on Monday, as a trough remains nearly stationary across northern Minnesota. At the surface, a north-to-south corridor of low-level moisture with dewpoints in the 60s F, will be in place from central Kansas northward into the eastern Dakotas. Moderate instability is forecast to develop along the western edge of this moist airmass, from western Nebraska into southwestern and central South Dakota. As destabilization takes place during the day, isolated thunderstorm development will be possible, mainly in areas where low-level convergence becomes maximized. Across much of the region, 0-6 km shear is forecast to be in the 35 to 45 knot range. This will support an isolated threat for severe gusts. Hail will also be possible in the central High Plains, where mid-level lapse rates are forecast to be steep. ..Broyles.. 08/03/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0101 AM CDT Sun Aug 03 2025 Valid 031200Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL AND SOUTHERN HIGH PLAINS... ...SUMMARY... Large to very large hail and damaging winds will be possible this afternoon and evening over parts of the central/southern High Plains. Additional strong to severe storms are probable in the Northwest during the afternoon. ...Central High Plains... Low-level upslope flow overspread by continued northwesterly flow aloft will support scattered storm development across the central High Plains by early afternoon. Near a weak surface low/lee trough, storms moving east off the higher terrain across WY and SD, will gradually encounter dewpoints in the upper 50s to low 60s F. This will allow for moderate instability and intensification of storms as they move into the deeper moisture, though shear will be weaker to the east. Steep low/mid-level lapse rates could support isolated damaging gusts and occasional hail with the strongest storms as semi-organized cluster gradually evolve. ...Parts of the Southern Plains... Any early morning MCS/cluster of storms is likely to be ongoing at the start of the period from western OK into the eastern TX Panhandle. This feature casts significant uncertainty on the convective evolution throughout the day across parts of TX, KS and OK. While these initial storms should slowly weaken through the morning, a convectively enhanced shortwave trough, embedded within the northwesterly flow aloft, will continue southeastward overspreading the prior cold pool. Lift from the upper trough, in combination with strong heating and low-level moist advection, could support storm regeneration over parts of central OK and north TX by early afternoon. A conditional risk for supercells capable of hail and damaging winds is possible given moderate instability and 35-40 kt of deep-layer shear. Across the southern High Plains, the trailing outflow from the morning convective complex should gradually modify over parts of southeastern CO and the TX/OK Panhandles. The left exit region of a 90+ kt upper-level jet will overspread the lee trough and modifying outflow around peak heating. This should support isolated supercell development across southeastern CO into the TX/OK Panhandles. The parameter space for large to very large hail will be quite favorable owing to elongated hodographs with deep-layer shear of 40-50 kt overlapping with MLCAPE of 2500-3500 J/kg, and mid-level lapse rates of 8-9 C/km. Backed low-level flow and stronger shear near the outflow boundary could also support a tornado or two given the expected supercell storm mode. With time, some upscale growth into a linear cluster or MCS is possible into the TX South Plains and western Red River Valley tonight. While uncertainty on the storm coverage remains given the overall modest forcing for ascent, this scenario, supported by several CAM solutions, seems reasonable. Should this occur, an increased risk for damaging gusts could accompany a linear cluster overnight into portions of west TX. ...Northwest... Modest surface moisture beneath a fairly pronounced shortwave trough over the eastern Pacific will move inland today supporting scatted to numerous thunderstorms across portions of the Northwest. A belt of stronger mid-level flow ahead of the trough will help to increase deep-layer shear to 30-40 kt, supporting some storm organization despite limited instability (SBCAPE generally less than 1000 J/kg). Steep lapse rates with inverted-v thermodynamic profiles and the potential for high-based semi-organized clusters will favor strong downdrafts capable of occasional severe gusts with the stronger storms. Small hail will also be possible with any more persistent clusters or weak supercell structures despite the limited buoyancy. ..Lyons.. 08/03/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0101 AM CDT Sun Aug 03 2025 Valid 031200Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL AND SOUTHERN HIGH PLAINS... ...SUMMARY... Large to very large hail and damaging winds will be possible this afternoon and evening over parts of the central/southern High Plains. Additional strong to severe storms are probable in the Northwest during the afternoon. ...Central High Plains... Low-level upslope flow overspread by continued northwesterly flow aloft will support scattered storm development across the central High Plains by early afternoon. Near a weak surface low/lee trough, storms moving east off the higher terrain across WY and SD, will gradually encounter dewpoints in the upper 50s to low 60s F. This will allow for moderate instability and intensification of storms as they move into the deeper moisture, though shear will be weaker to the east. Steep low/mid-level lapse rates could support isolated damaging gusts and occasional hail with the strongest storms as semi-organized cluster gradually evolve. ...Parts of the Southern Plains... Any early morning MCS/cluster of storms is likely to be ongoing at the start of the period from western OK into the eastern TX Panhandle. This feature casts significant uncertainty on the convective evolution throughout the day across parts of TX, KS and OK. While these initial storms should slowly weaken through the morning, a convectively enhanced shortwave trough, embedded within the northwesterly flow aloft, will continue southeastward overspreading the prior cold pool. Lift from the upper trough, in combination with strong heating and low-level moist advection, could support storm regeneration over parts of central OK and north TX by early afternoon. A conditional risk for supercells capable of hail and damaging winds is possible given moderate instability and 35-40 kt of deep-layer shear. Across the southern High Plains, the trailing outflow from the morning convective complex should gradually modify over parts of southeastern CO and the TX/OK Panhandles. The left exit region of a 90+ kt upper-level jet will overspread the lee trough and modifying outflow around peak heating. This should support isolated supercell development across southeastern CO into the TX/OK Panhandles. The parameter space for large to very large hail will be quite favorable owing to elongated hodographs with deep-layer shear of 40-50 kt overlapping with MLCAPE of 2500-3500 J/kg, and mid-level lapse rates of 8-9 C/km. Backed low-level flow and stronger shear near the outflow boundary could also support a tornado or two given the expected supercell storm mode. With time, some upscale growth into a linear cluster or MCS is possible into the TX South Plains and western Red River Valley tonight. While uncertainty on the storm coverage remains given the overall modest forcing for ascent, this scenario, supported by several CAM solutions, seems reasonable. Should this occur, an increased risk for damaging gusts could accompany a linear cluster overnight into portions of west TX. ...Northwest... Modest surface moisture beneath a fairly pronounced shortwave trough over the eastern Pacific will move inland today supporting scatted to numerous thunderstorms across portions of the Northwest. A belt of stronger mid-level flow ahead of the trough will help to increase deep-layer shear to 30-40 kt, supporting some storm organization despite limited instability (SBCAPE generally less than 1000 J/kg). Steep lapse rates with inverted-v thermodynamic profiles and the potential for high-based semi-organized clusters will favor strong downdrafts capable of occasional severe gusts with the stronger storms. Small hail will also be possible with any more persistent clusters or weak supercell structures despite the limited buoyancy. ..Lyons.. 08/03/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0101 AM CDT Sun Aug 03 2025 Valid 031200Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL AND SOUTHERN HIGH PLAINS... ...SUMMARY... Large to very large hail and damaging winds will be possible this afternoon and evening over parts of the central/southern High Plains. Additional strong to severe storms are probable in the Northwest during the afternoon. ...Central High Plains... Low-level upslope flow overspread by continued northwesterly flow aloft will support scattered storm development across the central High Plains by early afternoon. Near a weak surface low/lee trough, storms moving east off the higher terrain across WY and SD, will gradually encounter dewpoints in the upper 50s to low 60s F. This will allow for moderate instability and intensification of storms as they move into the deeper moisture, though shear will be weaker to the east. Steep low/mid-level lapse rates could support isolated damaging gusts and occasional hail with the strongest storms as semi-organized cluster gradually evolve. ...Parts of the Southern Plains... Any early morning MCS/cluster of storms is likely to be ongoing at the start of the period from western OK into the eastern TX Panhandle. This feature casts significant uncertainty on the convective evolution throughout the day across parts of TX, KS and OK. While these initial storms should slowly weaken through the morning, a convectively enhanced shortwave trough, embedded within the northwesterly flow aloft, will continue southeastward overspreading the prior cold pool. Lift from the upper trough, in combination with strong heating and low-level moist advection, could support storm regeneration over parts of central OK and north TX by early afternoon. A conditional risk for supercells capable of hail and damaging winds is possible given moderate instability and 35-40 kt of deep-layer shear. Across the southern High Plains, the trailing outflow from the morning convective complex should gradually modify over parts of southeastern CO and the TX/OK Panhandles. The left exit region of a 90+ kt upper-level jet will overspread the lee trough and modifying outflow around peak heating. This should support isolated supercell development across southeastern CO into the TX/OK Panhandles. The parameter space for large to very large hail will be quite favorable owing to elongated hodographs with deep-layer shear of 40-50 kt overlapping with MLCAPE of 2500-3500 J/kg, and mid-level lapse rates of 8-9 C/km. Backed low-level flow and stronger shear near the outflow boundary could also support a tornado or two given the expected supercell storm mode. With time, some upscale growth into a linear cluster or MCS is possible into the TX South Plains and western Red River Valley tonight. While uncertainty on the storm coverage remains given the overall modest forcing for ascent, this scenario, supported by several CAM solutions, seems reasonable. Should this occur, an increased risk for damaging gusts could accompany a linear cluster overnight into portions of west TX. ...Northwest... Modest surface moisture beneath a fairly pronounced shortwave trough over the eastern Pacific will move inland today supporting scatted to numerous thunderstorms across portions of the Northwest. A belt of stronger mid-level flow ahead of the trough will help to increase deep-layer shear to 30-40 kt, supporting some storm organization despite limited instability (SBCAPE generally less than 1000 J/kg). Steep lapse rates with inverted-v thermodynamic profiles and the potential for high-based semi-organized clusters will favor strong downdrafts capable of occasional severe gusts with the stronger storms. Small hail will also be possible with any more persistent clusters or weak supercell structures despite the limited buoyancy. ..Lyons.. 08/03/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0101 AM CDT Sun Aug 03 2025 Valid 031200Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL AND SOUTHERN HIGH PLAINS... ...SUMMARY... Large to very large hail and damaging winds will be possible this afternoon and evening over parts of the central/southern High Plains. Additional strong to severe storms are probable in the Northwest during the afternoon. ...Central High Plains... Low-level upslope flow overspread by continued northwesterly flow aloft will support scattered storm development across the central High Plains by early afternoon. Near a weak surface low/lee trough, storms moving east off the higher terrain across WY and SD, will gradually encounter dewpoints in the upper 50s to low 60s F. This will allow for moderate instability and intensification of storms as they move into the deeper moisture, though shear will be weaker to the east. Steep low/mid-level lapse rates could support isolated damaging gusts and occasional hail with the strongest storms as semi-organized cluster gradually evolve. ...Parts of the Southern Plains... Any early morning MCS/cluster of storms is likely to be ongoing at the start of the period from western OK into the eastern TX Panhandle. This feature casts significant uncertainty on the convective evolution throughout the day across parts of TX, KS and OK. While these initial storms should slowly weaken through the morning, a convectively enhanced shortwave trough, embedded within the northwesterly flow aloft, will continue southeastward overspreading the prior cold pool. Lift from the upper trough, in combination with strong heating and low-level moist advection, could support storm regeneration over parts of central OK and north TX by early afternoon. A conditional risk for supercells capable of hail and damaging winds is possible given moderate instability and 35-40 kt of deep-layer shear. Across the southern High Plains, the trailing outflow from the morning convective complex should gradually modify over parts of southeastern CO and the TX/OK Panhandles. The left exit region of a 90+ kt upper-level jet will overspread the lee trough and modifying outflow around peak heating. This should support isolated supercell development across southeastern CO into the TX/OK Panhandles. The parameter space for large to very large hail will be quite favorable owing to elongated hodographs with deep-layer shear of 40-50 kt overlapping with MLCAPE of 2500-3500 J/kg, and mid-level lapse rates of 8-9 C/km. Backed low-level flow and stronger shear near the outflow boundary could also support a tornado or two given the expected supercell storm mode. With time, some upscale growth into a linear cluster or MCS is possible into the TX South Plains and western Red River Valley tonight. While uncertainty on the storm coverage remains given the overall modest forcing for ascent, this scenario, supported by several CAM solutions, seems reasonable. Should this occur, an increased risk for damaging gusts could accompany a linear cluster overnight into portions of west TX. ...Northwest... Modest surface moisture beneath a fairly pronounced shortwave trough over the eastern Pacific will move inland today supporting scatted to numerous thunderstorms across portions of the Northwest. A belt of stronger mid-level flow ahead of the trough will help to increase deep-layer shear to 30-40 kt, supporting some storm organization despite limited instability (SBCAPE generally less than 1000 J/kg). Steep lapse rates with inverted-v thermodynamic profiles and the potential for high-based semi-organized clusters will favor strong downdrafts capable of occasional severe gusts with the stronger storms. Small hail will also be possible with any more persistent clusters or weak supercell structures despite the limited buoyancy. ..Lyons.. 08/03/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0101 AM CDT Sun Aug 03 2025 Valid 031200Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL AND SOUTHERN HIGH PLAINS... ...SUMMARY... Large to very large hail and damaging winds will be possible this afternoon and evening over parts of the central/southern High Plains. Additional strong to severe storms are probable in the Northwest during the afternoon. ...Central High Plains... Low-level upslope flow overspread by continued northwesterly flow aloft will support scattered storm development across the central High Plains by early afternoon. Near a weak surface low/lee trough, storms moving east off the higher terrain across WY and SD, will gradually encounter dewpoints in the upper 50s to low 60s F. This will allow for moderate instability and intensification of storms as they move into the deeper moisture, though shear will be weaker to the east. Steep low/mid-level lapse rates could support isolated damaging gusts and occasional hail with the strongest storms as semi-organized cluster gradually evolve. ...Parts of the Southern Plains... Any early morning MCS/cluster of storms is likely to be ongoing at the start of the period from western OK into the eastern TX Panhandle. This feature casts significant uncertainty on the convective evolution throughout the day across parts of TX, KS and OK. While these initial storms should slowly weaken through the morning, a convectively enhanced shortwave trough, embedded within the northwesterly flow aloft, will continue southeastward overspreading the prior cold pool. Lift from the upper trough, in combination with strong heating and low-level moist advection, could support storm regeneration over parts of central OK and north TX by early afternoon. A conditional risk for supercells capable of hail and damaging winds is possible given moderate instability and 35-40 kt of deep-layer shear. Across the southern High Plains, the trailing outflow from the morning convective complex should gradually modify over parts of southeastern CO and the TX/OK Panhandles. The left exit region of a 90+ kt upper-level jet will overspread the lee trough and modifying outflow around peak heating. This should support isolated supercell development across southeastern CO into the TX/OK Panhandles. The parameter space for large to very large hail will be quite favorable owing to elongated hodographs with deep-layer shear of 40-50 kt overlapping with MLCAPE of 2500-3500 J/kg, and mid-level lapse rates of 8-9 C/km. Backed low-level flow and stronger shear near the outflow boundary could also support a tornado or two given the expected supercell storm mode. With time, some upscale growth into a linear cluster or MCS is possible into the TX South Plains and western Red River Valley tonight. While uncertainty on the storm coverage remains given the overall modest forcing for ascent, this scenario, supported by several CAM solutions, seems reasonable. Should this occur, an increased risk for damaging gusts could accompany a linear cluster overnight into portions of west TX. ...Northwest... Modest surface moisture beneath a fairly pronounced shortwave trough over the eastern Pacific will move inland today supporting scatted to numerous thunderstorms across portions of the Northwest. A belt of stronger mid-level flow ahead of the trough will help to increase deep-layer shear to 30-40 kt, supporting some storm organization despite limited instability (SBCAPE generally less than 1000 J/kg). Steep lapse rates with inverted-v thermodynamic profiles and the potential for high-based semi-organized clusters will favor strong downdrafts capable of occasional severe gusts with the stronger storms. Small hail will also be possible with any more persistent clusters or weak supercell structures despite the limited buoyancy. ..Lyons.. 08/03/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0101 AM CDT Sun Aug 03 2025 Valid 031200Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL AND SOUTHERN HIGH PLAINS... ...SUMMARY... Large to very large hail and damaging winds will be possible this afternoon and evening over parts of the central/southern High Plains. Additional strong to severe storms are probable in the Northwest during the afternoon. ...Central High Plains... Low-level upslope flow overspread by continued northwesterly flow aloft will support scattered storm development across the central High Plains by early afternoon. Near a weak surface low/lee trough, storms moving east off the higher terrain across WY and SD, will gradually encounter dewpoints in the upper 50s to low 60s F. This will allow for moderate instability and intensification of storms as they move into the deeper moisture, though shear will be weaker to the east. Steep low/mid-level lapse rates could support isolated damaging gusts and occasional hail with the strongest storms as semi-organized cluster gradually evolve. ...Parts of the Southern Plains... Any early morning MCS/cluster of storms is likely to be ongoing at the start of the period from western OK into the eastern TX Panhandle. This feature casts significant uncertainty on the convective evolution throughout the day across parts of TX, KS and OK. While these initial storms should slowly weaken through the morning, a convectively enhanced shortwave trough, embedded within the northwesterly flow aloft, will continue southeastward overspreading the prior cold pool. Lift from the upper trough, in combination with strong heating and low-level moist advection, could support storm regeneration over parts of central OK and north TX by early afternoon. A conditional risk for supercells capable of hail and damaging winds is possible given moderate instability and 35-40 kt of deep-layer shear. Across the southern High Plains, the trailing outflow from the morning convective complex should gradually modify over parts of southeastern CO and the TX/OK Panhandles. The left exit region of a 90+ kt upper-level jet will overspread the lee trough and modifying outflow around peak heating. This should support isolated supercell development across southeastern CO into the TX/OK Panhandles. The parameter space for large to very large hail will be quite favorable owing to elongated hodographs with deep-layer shear of 40-50 kt overlapping with MLCAPE of 2500-3500 J/kg, and mid-level lapse rates of 8-9 C/km. Backed low-level flow and stronger shear near the outflow boundary could also support a tornado or two given the expected supercell storm mode. With time, some upscale growth into a linear cluster or MCS is possible into the TX South Plains and western Red River Valley tonight. While uncertainty on the storm coverage remains given the overall modest forcing for ascent, this scenario, supported by several CAM solutions, seems reasonable. Should this occur, an increased risk for damaging gusts could accompany a linear cluster overnight into portions of west TX. ...Northwest... Modest surface moisture beneath a fairly pronounced shortwave trough over the eastern Pacific will move inland today supporting scatted to numerous thunderstorms across portions of the Northwest. A belt of stronger mid-level flow ahead of the trough will help to increase deep-layer shear to 30-40 kt, supporting some storm organization despite limited instability (SBCAPE generally less than 1000 J/kg). Steep lapse rates with inverted-v thermodynamic profiles and the potential for high-based semi-organized clusters will favor strong downdrafts capable of occasional severe gusts with the stronger storms. Small hail will also be possible with any more persistent clusters or weak supercell structures despite the limited buoyancy. ..Lyons.. 08/03/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0101 AM CDT Sun Aug 03 2025 Valid 031200Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL AND SOUTHERN HIGH PLAINS... ...SUMMARY... Large to very large hail and damaging winds will be possible this afternoon and evening over parts of the central/southern High Plains. Additional strong to severe storms are probable in the Northwest during the afternoon. ...Central High Plains... Low-level upslope flow overspread by continued northwesterly flow aloft will support scattered storm development across the central High Plains by early afternoon. Near a weak surface low/lee trough, storms moving east off the higher terrain across WY and SD, will gradually encounter dewpoints in the upper 50s to low 60s F. This will allow for moderate instability and intensification of storms as they move into the deeper moisture, though shear will be weaker to the east. Steep low/mid-level lapse rates could support isolated damaging gusts and occasional hail with the strongest storms as semi-organized cluster gradually evolve. ...Parts of the Southern Plains... Any early morning MCS/cluster of storms is likely to be ongoing at the start of the period from western OK into the eastern TX Panhandle. This feature casts significant uncertainty on the convective evolution throughout the day across parts of TX, KS and OK. While these initial storms should slowly weaken through the morning, a convectively enhanced shortwave trough, embedded within the northwesterly flow aloft, will continue southeastward overspreading the prior cold pool. Lift from the upper trough, in combination with strong heating and low-level moist advection, could support storm regeneration over parts of central OK and north TX by early afternoon. A conditional risk for supercells capable of hail and damaging winds is possible given moderate instability and 35-40 kt of deep-layer shear. Across the southern High Plains, the trailing outflow from the morning convective complex should gradually modify over parts of southeastern CO and the TX/OK Panhandles. The left exit region of a 90+ kt upper-level jet will overspread the lee trough and modifying outflow around peak heating. This should support isolated supercell development across southeastern CO into the TX/OK Panhandles. The parameter space for large to very large hail will be quite favorable owing to elongated hodographs with deep-layer shear of 40-50 kt overlapping with MLCAPE of 2500-3500 J/kg, and mid-level lapse rates of 8-9 C/km. Backed low-level flow and stronger shear near the outflow boundary could also support a tornado or two given the expected supercell storm mode. With time, some upscale growth into a linear cluster or MCS is possible into the TX South Plains and western Red River Valley tonight. While uncertainty on the storm coverage remains given the overall modest forcing for ascent, this scenario, supported by several CAM solutions, seems reasonable. Should this occur, an increased risk for damaging gusts could accompany a linear cluster overnight into portions of west TX. ...Northwest... Modest surface moisture beneath a fairly pronounced shortwave trough over the eastern Pacific will move inland today supporting scatted to numerous thunderstorms across portions of the Northwest. A belt of stronger mid-level flow ahead of the trough will help to increase deep-layer shear to 30-40 kt, supporting some storm organization despite limited instability (SBCAPE generally less than 1000 J/kg). Steep lapse rates with inverted-v thermodynamic profiles and the potential for high-based semi-organized clusters will favor strong downdrafts capable of occasional severe gusts with the stronger storms. Small hail will also be possible with any more persistent clusters or weak supercell structures despite the limited buoyancy. ..Lyons.. 08/03/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0101 AM CDT Sun Aug 03 2025 Valid 031200Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL AND SOUTHERN HIGH PLAINS... ...SUMMARY... Large to very large hail and damaging winds will be possible this afternoon and evening over parts of the central/southern High Plains. Additional strong to severe storms are probable in the Northwest during the afternoon. ...Central High Plains... Low-level upslope flow overspread by continued northwesterly flow aloft will support scattered storm development across the central High Plains by early afternoon. Near a weak surface low/lee trough, storms moving east off the higher terrain across WY and SD, will gradually encounter dewpoints in the upper 50s to low 60s F. This will allow for moderate instability and intensification of storms as they move into the deeper moisture, though shear will be weaker to the east. Steep low/mid-level lapse rates could support isolated damaging gusts and occasional hail with the strongest storms as semi-organized cluster gradually evolve. ...Parts of the Southern Plains... Any early morning MCS/cluster of storms is likely to be ongoing at the start of the period from western OK into the eastern TX Panhandle. This feature casts significant uncertainty on the convective evolution throughout the day across parts of TX, KS and OK. While these initial storms should slowly weaken through the morning, a convectively enhanced shortwave trough, embedded within the northwesterly flow aloft, will continue southeastward overspreading the prior cold pool. Lift from the upper trough, in combination with strong heating and low-level moist advection, could support storm regeneration over parts of central OK and north TX by early afternoon. A conditional risk for supercells capable of hail and damaging winds is possible given moderate instability and 35-40 kt of deep-layer shear. Across the southern High Plains, the trailing outflow from the morning convective complex should gradually modify over parts of southeastern CO and the TX/OK Panhandles. The left exit region of a 90+ kt upper-level jet will overspread the lee trough and modifying outflow around peak heating. This should support isolated supercell development across southeastern CO into the TX/OK Panhandles. The parameter space for large to very large hail will be quite favorable owing to elongated hodographs with deep-layer shear of 40-50 kt overlapping with MLCAPE of 2500-3500 J/kg, and mid-level lapse rates of 8-9 C/km. Backed low-level flow and stronger shear near the outflow boundary could also support a tornado or two given the expected supercell storm mode. With time, some upscale growth into a linear cluster or MCS is possible into the TX South Plains and western Red River Valley tonight. While uncertainty on the storm coverage remains given the overall modest forcing for ascent, this scenario, supported by several CAM solutions, seems reasonable. Should this occur, an increased risk for damaging gusts could accompany a linear cluster overnight into portions of west TX. ...Northwest... Modest surface moisture beneath a fairly pronounced shortwave trough over the eastern Pacific will move inland today supporting scatted to numerous thunderstorms across portions of the Northwest. A belt of stronger mid-level flow ahead of the trough will help to increase deep-layer shear to 30-40 kt, supporting some storm organization despite limited instability (SBCAPE generally less than 1000 J/kg). Steep lapse rates with inverted-v thermodynamic profiles and the potential for high-based semi-organized clusters will favor strong downdrafts capable of occasional severe gusts with the stronger storms. Small hail will also be possible with any more persistent clusters or weak supercell structures despite the limited buoyancy. ..Lyons.. 08/03/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0101 AM CDT Sun Aug 03 2025 Valid 031200Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL AND SOUTHERN HIGH PLAINS... ...SUMMARY... Large to very large hail and damaging winds will be possible this afternoon and evening over parts of the central/southern High Plains. Additional strong to severe storms are probable in the Northwest during the afternoon. ...Central High Plains... Low-level upslope flow overspread by continued northwesterly flow aloft will support scattered storm development across the central High Plains by early afternoon. Near a weak surface low/lee trough, storms moving east off the higher terrain across WY and SD, will gradually encounter dewpoints in the upper 50s to low 60s F. This will allow for moderate instability and intensification of storms as they move into the deeper moisture, though shear will be weaker to the east. Steep low/mid-level lapse rates could support isolated damaging gusts and occasional hail with the strongest storms as semi-organized cluster gradually evolve. ...Parts of the Southern Plains... Any early morning MCS/cluster of storms is likely to be ongoing at the start of the period from western OK into the eastern TX Panhandle. This feature casts significant uncertainty on the convective evolution throughout the day across parts of TX, KS and OK. While these initial storms should slowly weaken through the morning, a convectively enhanced shortwave trough, embedded within the northwesterly flow aloft, will continue southeastward overspreading the prior cold pool. Lift from the upper trough, in combination with strong heating and low-level moist advection, could support storm regeneration over parts of central OK and north TX by early afternoon. A conditional risk for supercells capable of hail and damaging winds is possible given moderate instability and 35-40 kt of deep-layer shear. Across the southern High Plains, the trailing outflow from the morning convective complex should gradually modify over parts of southeastern CO and the TX/OK Panhandles. The left exit region of a 90+ kt upper-level jet will overspread the lee trough and modifying outflow around peak heating. This should support isolated supercell development across southeastern CO into the TX/OK Panhandles. The parameter space for large to very large hail will be quite favorable owing to elongated hodographs with deep-layer shear of 40-50 kt overlapping with MLCAPE of 2500-3500 J/kg, and mid-level lapse rates of 8-9 C/km. Backed low-level flow and stronger shear near the outflow boundary could also support a tornado or two given the expected supercell storm mode. With time, some upscale growth into a linear cluster or MCS is possible into the TX South Plains and western Red River Valley tonight. While uncertainty on the storm coverage remains given the overall modest forcing for ascent, this scenario, supported by several CAM solutions, seems reasonable. Should this occur, an increased risk for damaging gusts could accompany a linear cluster overnight into portions of west TX. ...Northwest... Modest surface moisture beneath a fairly pronounced shortwave trough over the eastern Pacific will move inland today supporting scatted to numerous thunderstorms across portions of the Northwest. A belt of stronger mid-level flow ahead of the trough will help to increase deep-layer shear to 30-40 kt, supporting some storm organization despite limited instability (SBCAPE generally less than 1000 J/kg). Steep lapse rates with inverted-v thermodynamic profiles and the potential for high-based semi-organized clusters will favor strong downdrafts capable of occasional severe gusts with the stronger storms. Small hail will also be possible with any more persistent clusters or weak supercell structures despite the limited buoyancy. ..Lyons.. 08/03/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0101 AM CDT Sun Aug 03 2025 Valid 031200Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL AND SOUTHERN HIGH PLAINS... ...SUMMARY... Large to very large hail and damaging winds will be possible this afternoon and evening over parts of the central/southern High Plains. Additional strong to severe storms are probable in the Northwest during the afternoon. ...Central High Plains... Low-level upslope flow overspread by continued northwesterly flow aloft will support scattered storm development across the central High Plains by early afternoon. Near a weak surface low/lee trough, storms moving east off the higher terrain across WY and SD, will gradually encounter dewpoints in the upper 50s to low 60s F. This will allow for moderate instability and intensification of storms as they move into the deeper moisture, though shear will be weaker to the east. Steep low/mid-level lapse rates could support isolated damaging gusts and occasional hail with the strongest storms as semi-organized cluster gradually evolve. ...Parts of the Southern Plains... Any early morning MCS/cluster of storms is likely to be ongoing at the start of the period from western OK into the eastern TX Panhandle. This feature casts significant uncertainty on the convective evolution throughout the day across parts of TX, KS and OK. While these initial storms should slowly weaken through the morning, a convectively enhanced shortwave trough, embedded within the northwesterly flow aloft, will continue southeastward overspreading the prior cold pool. Lift from the upper trough, in combination with strong heating and low-level moist advection, could support storm regeneration over parts of central OK and north TX by early afternoon. A conditional risk for supercells capable of hail and damaging winds is possible given moderate instability and 35-40 kt of deep-layer shear. Across the southern High Plains, the trailing outflow from the morning convective complex should gradually modify over parts of southeastern CO and the TX/OK Panhandles. The left exit region of a 90+ kt upper-level jet will overspread the lee trough and modifying outflow around peak heating. This should support isolated supercell development across southeastern CO into the TX/OK Panhandles. The parameter space for large to very large hail will be quite favorable owing to elongated hodographs with deep-layer shear of 40-50 kt overlapping with MLCAPE of 2500-3500 J/kg, and mid-level lapse rates of 8-9 C/km. Backed low-level flow and stronger shear near the outflow boundary could also support a tornado or two given the expected supercell storm mode. With time, some upscale growth into a linear cluster or MCS is possible into the TX South Plains and western Red River Valley tonight. While uncertainty on the storm coverage remains given the overall modest forcing for ascent, this scenario, supported by several CAM solutions, seems reasonable. Should this occur, an increased risk for damaging gusts could accompany a linear cluster overnight into portions of west TX. ...Northwest... Modest surface moisture beneath a fairly pronounced shortwave trough over the eastern Pacific will move inland today supporting scatted to numerous thunderstorms across portions of the Northwest. A belt of stronger mid-level flow ahead of the trough will help to increase deep-layer shear to 30-40 kt, supporting some storm organization despite limited instability (SBCAPE generally less than 1000 J/kg). Steep lapse rates with inverted-v thermodynamic profiles and the potential for high-based semi-organized clusters will favor strong downdrafts capable of occasional severe gusts with the stronger storms. Small hail will also be possible with any more persistent clusters or weak supercell structures despite the limited buoyancy. ..Lyons.. 08/03/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0101 AM CDT Sun Aug 03 2025 Valid 031200Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL AND SOUTHERN HIGH PLAINS... ...SUMMARY... Large to very large hail and damaging winds will be possible this afternoon and evening over parts of the central/southern High Plains. Additional strong to severe storms are probable in the Northwest during the afternoon. ...Central High Plains... Low-level upslope flow overspread by continued northwesterly flow aloft will support scattered storm development across the central High Plains by early afternoon. Near a weak surface low/lee trough, storms moving east off the higher terrain across WY and SD, will gradually encounter dewpoints in the upper 50s to low 60s F. This will allow for moderate instability and intensification of storms as they move into the deeper moisture, though shear will be weaker to the east. Steep low/mid-level lapse rates could support isolated damaging gusts and occasional hail with the strongest storms as semi-organized cluster gradually evolve. ...Parts of the Southern Plains... Any early morning MCS/cluster of storms is likely to be ongoing at the start of the period from western OK into the eastern TX Panhandle. This feature casts significant uncertainty on the convective evolution throughout the day across parts of TX, KS and OK. While these initial storms should slowly weaken through the morning, a convectively enhanced shortwave trough, embedded within the northwesterly flow aloft, will continue southeastward overspreading the prior cold pool. Lift from the upper trough, in combination with strong heating and low-level moist advection, could support storm regeneration over parts of central OK and north TX by early afternoon. A conditional risk for supercells capable of hail and damaging winds is possible given moderate instability and 35-40 kt of deep-layer shear. Across the southern High Plains, the trailing outflow from the morning convective complex should gradually modify over parts of southeastern CO and the TX/OK Panhandles. The left exit region of a 90+ kt upper-level jet will overspread the lee trough and modifying outflow around peak heating. This should support isolated supercell development across southeastern CO into the TX/OK Panhandles. The parameter space for large to very large hail will be quite favorable owing to elongated hodographs with deep-layer shear of 40-50 kt overlapping with MLCAPE of 2500-3500 J/kg, and mid-level lapse rates of 8-9 C/km. Backed low-level flow and stronger shear near the outflow boundary could also support a tornado or two given the expected supercell storm mode. With time, some upscale growth into a linear cluster or MCS is possible into the TX South Plains and western Red River Valley tonight. While uncertainty on the storm coverage remains given the overall modest forcing for ascent, this scenario, supported by several CAM solutions, seems reasonable. Should this occur, an increased risk for damaging gusts could accompany a linear cluster overnight into portions of west TX. ...Northwest... Modest surface moisture beneath a fairly pronounced shortwave trough over the eastern Pacific will move inland today supporting scatted to numerous thunderstorms across portions of the Northwest. A belt of stronger mid-level flow ahead of the trough will help to increase deep-layer shear to 30-40 kt, supporting some storm organization despite limited instability (SBCAPE generally less than 1000 J/kg). Steep lapse rates with inverted-v thermodynamic profiles and the potential for high-based semi-organized clusters will favor strong downdrafts capable of occasional severe gusts with the stronger storms. Small hail will also be possible with any more persistent clusters or weak supercell structures despite the limited buoyancy. ..Lyons.. 08/03/2025 Read more