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SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0156 AM CDT Mon Aug 04 2025 Valid 051200Z - 061200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHERN/CENTRAL UTAH AND FAR NORTHERN ARIZONA... ...Synopsis... Broad midlevel troughing will persist across the Northwest/Intermountain West, while an expansive midlevel anticyclone builds over the Southwest and southern/central Rockies. ...Great Basin into the central/northern Rockies... Between the expansive midlevel anticyclone and broad midlevel troughing, a belt of enhanced deep-layer west-southwesterly flow will persist across the Great Basin into the northern/central Rockies. Diurnal heating amid a dry antecedent air mass will yield a deeply mixed boundary layer (single-digit to lower teens RH). These dry conditions combined with 15-20 mph sustained west-southwesterly surface winds will lead to widespread elevated fire-weather conditions, with critical conditions expected over southern/central UT into northern AZ (where the overlap of strong winds and low RH atop receptive fuels will be maximized). ..Weinman.. 08/04/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0156 AM CDT Mon Aug 04 2025 Valid 051200Z - 061200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHERN/CENTRAL UTAH AND FAR NORTHERN ARIZONA... ...Synopsis... Broad midlevel troughing will persist across the Northwest/Intermountain West, while an expansive midlevel anticyclone builds over the Southwest and southern/central Rockies. ...Great Basin into the central/northern Rockies... Between the expansive midlevel anticyclone and broad midlevel troughing, a belt of enhanced deep-layer west-southwesterly flow will persist across the Great Basin into the northern/central Rockies. Diurnal heating amid a dry antecedent air mass will yield a deeply mixed boundary layer (single-digit to lower teens RH). These dry conditions combined with 15-20 mph sustained west-southwesterly surface winds will lead to widespread elevated fire-weather conditions, with critical conditions expected over southern/central UT into northern AZ (where the overlap of strong winds and low RH atop receptive fuels will be maximized). ..Weinman.. 08/04/2025 ...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 0156 AM CDT Mon Aug 04 2025 Valid 041200Z - 051200Z ...CRITICAL FIRE WEATHER AREA FOR PARTS OF THE GREAT BASIN INTO THE CENTRAL ROCKIES... ...Synopsis... Along the northwestern periphery of a large-scale ridge extending from the Southwest into the northern Plains, a compact/robust midlevel trough will advance east-northeastward from the Northwest into the northern Rockies during the day. ...Great Basin into the central Rockies... Between the large-scale ridge and midlevel trough, a belt of moderate deep-layer west-southwesterly flow will overspread the Great Basin into the central Rockies through the afternoon. Here, deep boundary-layer mixing into the enhanced flow aloft will favor widespread single-digit RH and 15-25 mph sustained west-southwesterly surface winds. These dry/windy conditions will lead to critical fire-weather conditions across much of UT and adjacent states, given very receptive fuels. ...Dry Thunderstorms - Intermountain West/Northern Rockies... Strong/focused forcing for ascent accompanying the midlevel trough will aid in thunderstorm development across much of the Intermountain West and northern Rockies throughout the day. Along the southern periphery of deeper midlevel moisture across parts of the Northwest into the northern Rockies, isolated high-based thunderstorms are expected in an air mass characterized by 0.60-0.75 inch PW and inverted-V soundings. This will promote mostly dry thunderstorms with a risk of lightning-induced ignitions and strong-severe outflow winds. Reference the SPC Day 1 Convective Outlook for information on the severe risk. ..Weinman.. 08/04/2025 ...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 0156 AM CDT Mon Aug 04 2025 Valid 041200Z - 051200Z ...CRITICAL FIRE WEATHER AREA FOR PARTS OF THE GREAT BASIN INTO THE CENTRAL ROCKIES... ...Synopsis... Along the northwestern periphery of a large-scale ridge extending from the Southwest into the northern Plains, a compact/robust midlevel trough will advance east-northeastward from the Northwest into the northern Rockies during the day. ...Great Basin into the central Rockies... Between the large-scale ridge and midlevel trough, a belt of moderate deep-layer west-southwesterly flow will overspread the Great Basin into the central Rockies through the afternoon. Here, deep boundary-layer mixing into the enhanced flow aloft will favor widespread single-digit RH and 15-25 mph sustained west-southwesterly surface winds. These dry/windy conditions will lead to critical fire-weather conditions across much of UT and adjacent states, given very receptive fuels. ...Dry Thunderstorms - Intermountain West/Northern Rockies... Strong/focused forcing for ascent accompanying the midlevel trough will aid in thunderstorm development across much of the Intermountain West and northern Rockies throughout the day. Along the southern periphery of deeper midlevel moisture across parts of the Northwest into the northern Rockies, isolated high-based thunderstorms are expected in an air mass characterized by 0.60-0.75 inch PW and inverted-V soundings. This will promote mostly dry thunderstorms with a risk of lightning-induced ignitions and strong-severe outflow winds. Reference the SPC Day 1 Convective Outlook for information on the severe risk. ..Weinman.. 08/04/2025 ...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 0156 AM CDT Mon Aug 04 2025 Valid 041200Z - 051200Z ...CRITICAL FIRE WEATHER AREA FOR PARTS OF THE GREAT BASIN INTO THE CENTRAL ROCKIES... ...Synopsis... Along the northwestern periphery of a large-scale ridge extending from the Southwest into the northern Plains, a compact/robust midlevel trough will advance east-northeastward from the Northwest into the northern Rockies during the day. ...Great Basin into the central Rockies... Between the large-scale ridge and midlevel trough, a belt of moderate deep-layer west-southwesterly flow will overspread the Great Basin into the central Rockies through the afternoon. Here, deep boundary-layer mixing into the enhanced flow aloft will favor widespread single-digit RH and 15-25 mph sustained west-southwesterly surface winds. These dry/windy conditions will lead to critical fire-weather conditions across much of UT and adjacent states, given very receptive fuels. ...Dry Thunderstorms - Intermountain West/Northern Rockies... Strong/focused forcing for ascent accompanying the midlevel trough will aid in thunderstorm development across much of the Intermountain West and northern Rockies throughout the day. Along the southern periphery of deeper midlevel moisture across parts of the Northwest into the northern Rockies, isolated high-based thunderstorms are expected in an air mass characterized by 0.60-0.75 inch PW and inverted-V soundings. This will promote mostly dry thunderstorms with a risk of lightning-induced ignitions and strong-severe outflow winds. Reference the SPC Day 1 Convective Outlook for information on the severe risk. ..Weinman.. 08/04/2025 ...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 0156 AM CDT Mon Aug 04 2025 Valid 041200Z - 051200Z ...CRITICAL FIRE WEATHER AREA FOR PARTS OF THE GREAT BASIN INTO THE CENTRAL ROCKIES... ...Synopsis... Along the northwestern periphery of a large-scale ridge extending from the Southwest into the northern Plains, a compact/robust midlevel trough will advance east-northeastward from the Northwest into the northern Rockies during the day. ...Great Basin into the central Rockies... Between the large-scale ridge and midlevel trough, a belt of moderate deep-layer west-southwesterly flow will overspread the Great Basin into the central Rockies through the afternoon. Here, deep boundary-layer mixing into the enhanced flow aloft will favor widespread single-digit RH and 15-25 mph sustained west-southwesterly surface winds. These dry/windy conditions will lead to critical fire-weather conditions across much of UT and adjacent states, given very receptive fuels. ...Dry Thunderstorms - Intermountain West/Northern Rockies... Strong/focused forcing for ascent accompanying the midlevel trough will aid in thunderstorm development across much of the Intermountain West and northern Rockies throughout the day. Along the southern periphery of deeper midlevel moisture across parts of the Northwest into the northern Rockies, isolated high-based thunderstorms are expected in an air mass characterized by 0.60-0.75 inch PW and inverted-V soundings. This will promote mostly dry thunderstorms with a risk of lightning-induced ignitions and strong-severe outflow winds. Reference the SPC Day 1 Convective Outlook for information on the severe risk. ..Weinman.. 08/04/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

MD 1883 CONCERNING SEVERE THUNDERSTORM WATCH 570... FOR PARTS OF SOUTHWEST/CENTRAL OK INTO FAR NORTH TX
Mesoscale Discussion 1883 NWS Storm Prediction Center Norman OK 1141 PM CDT Sun Aug 03 2025 Areas affected...Parts of southwest/central OK into far north TX Concerning...Severe Thunderstorm Watch 570... Valid 040441Z - 040615Z The severe weather threat for Severe Thunderstorm Watch 570 continues. SUMMARY...A threat for isolated strong to severe gusts and localized hail may continue into the early overnight hours. DISCUSSION...An MCS is propagating southeastward toward central OK as of 0430 UTC. Measured gusts over the last hour have generally been in the 45-55 mph range, but this system has a well-defined cold pool and could continue to pose a short-term threat for strong to locally severe gusts. Moderate buoyancy and favorable deep-layer shear could also support an isolated hail threat with any vigorous updraft development along the gust front. Recent objective analyses depict relatively weaker MLCINH and stronger instability to the southeast of this system, which may allow it to continue moving toward southern/central OK into the early overnight hours. However, somewhat weaker deep-layer shear with eastward extent and the lack of a stronger nocturnal low-level jet may tend to limit the organization of this system with time. The remaining severe threat may remain rather isolated, but trends will be continue to be monitored regarding the need for any local watch expansion or new watch issuance. ..Dean.. 08/04/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...TSA...FWD...OUN... LAT...LON 35189929 35639862 36449836 36439765 35649648 34669657 33629705 33739840 34509937 34819943 35189929 MOST PROBABLE PEAK WIND GUST...55-70 MPH MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1257 AM CDT Mon Aug 04 2025 Valid 051200Z - 061200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN PLAINS... ...SUMMARY... Thunderstorms associated with a threat for severe gusts and isolated large hail will be possible across parts of the central and northern Plains on Tuesday. ...Central and Northern Plains... A mid-level shortwave trough will move into the northern Plains on Tuesday. At the surface, a trough is forecast to sharpen during the day across the far western Dakotas. To the east of the trough, a moist airmass will be in place across much of the northern Plains. By afternoon, a north-to-south axis of moderate instability is forecast to develop to the east of the surface trough from western Nebraska northward into the western Dakotas. Within the moist sector, model consensus suggests that MLCAPE will peak in the 2500 to 3500 J/kg range, with the overall maximum located in western South Dakota. Low-level convergence will likely increase near and to the east of the surface trough, with scattered convective initiation expected near the trough in the late afternoon. These storms should spread eastward across west-central South Dakota and southwestern North Dakota during the late afternoon and early evening. A severe threat appears likely. Forecast soundings during the late afternoon across northwestern South Dakota have supercell wind profiles, with directional shear in the low to mid-levels, and 35 to 40 knots of 0-6 km shear. In addition, 700-500 mb lapse rates are forecast to be near 8 C/km. This environment would favor isolated large hail with rotating cells that remain discrete. A potential for severe wind gusts will also be possible, mainly with short line segments that form within a larger-scale cluster. The severe threat should persist into the mid evening, and could extend southward into northern Nebraska. However, severe threat magnitude is expected to be more isolated with southward extent, mainly due to more limited large-scale ascent. Further north into parts of north-central North Dakota and westward into northeast Montana, an isolated severe threat will be possible during the late afternoon and early evening. However, the combination of instability and deep-layer shear is expected less favorable than in areas to the south. This will likely keep any severe threat localized. ..Broyles.. 08/04/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1257 AM CDT Mon Aug 04 2025 Valid 051200Z - 061200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN PLAINS... ...SUMMARY... Thunderstorms associated with a threat for severe gusts and isolated large hail will be possible across parts of the central and northern Plains on Tuesday. ...Central and Northern Plains... A mid-level shortwave trough will move into the northern Plains on Tuesday. At the surface, a trough is forecast to sharpen during the day across the far western Dakotas. To the east of the trough, a moist airmass will be in place across much of the northern Plains. By afternoon, a north-to-south axis of moderate instability is forecast to develop to the east of the surface trough from western Nebraska northward into the western Dakotas. Within the moist sector, model consensus suggests that MLCAPE will peak in the 2500 to 3500 J/kg range, with the overall maximum located in western South Dakota. Low-level convergence will likely increase near and to the east of the surface trough, with scattered convective initiation expected near the trough in the late afternoon. These storms should spread eastward across west-central South Dakota and southwestern North Dakota during the late afternoon and early evening. A severe threat appears likely. Forecast soundings during the late afternoon across northwestern South Dakota have supercell wind profiles, with directional shear in the low to mid-levels, and 35 to 40 knots of 0-6 km shear. In addition, 700-500 mb lapse rates are forecast to be near 8 C/km. This environment would favor isolated large hail with rotating cells that remain discrete. A potential for severe wind gusts will also be possible, mainly with short line segments that form within a larger-scale cluster. The severe threat should persist into the mid evening, and could extend southward into northern Nebraska. However, severe threat magnitude is expected to be more isolated with southward extent, mainly due to more limited large-scale ascent. Further north into parts of north-central North Dakota and westward into northeast Montana, an isolated severe threat will be possible during the late afternoon and early evening. However, the combination of instability and deep-layer shear is expected less favorable than in areas to the south. This will likely keep any severe threat localized. ..Broyles.. 08/04/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1257 AM CDT Mon Aug 04 2025 Valid 051200Z - 061200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN PLAINS... ...SUMMARY... Thunderstorms associated with a threat for severe gusts and isolated large hail will be possible across parts of the central and northern Plains on Tuesday. ...Central and Northern Plains... A mid-level shortwave trough will move into the northern Plains on Tuesday. At the surface, a trough is forecast to sharpen during the day across the far western Dakotas. To the east of the trough, a moist airmass will be in place across much of the northern Plains. By afternoon, a north-to-south axis of moderate instability is forecast to develop to the east of the surface trough from western Nebraska northward into the western Dakotas. Within the moist sector, model consensus suggests that MLCAPE will peak in the 2500 to 3500 J/kg range, with the overall maximum located in western South Dakota. Low-level convergence will likely increase near and to the east of the surface trough, with scattered convective initiation expected near the trough in the late afternoon. These storms should spread eastward across west-central South Dakota and southwestern North Dakota during the late afternoon and early evening. A severe threat appears likely. Forecast soundings during the late afternoon across northwestern South Dakota have supercell wind profiles, with directional shear in the low to mid-levels, and 35 to 40 knots of 0-6 km shear. In addition, 700-500 mb lapse rates are forecast to be near 8 C/km. This environment would favor isolated large hail with rotating cells that remain discrete. A potential for severe wind gusts will also be possible, mainly with short line segments that form within a larger-scale cluster. The severe threat should persist into the mid evening, and could extend southward into northern Nebraska. However, severe threat magnitude is expected to be more isolated with southward extent, mainly due to more limited large-scale ascent. Further north into parts of north-central North Dakota and westward into northeast Montana, an isolated severe threat will be possible during the late afternoon and early evening. However, the combination of instability and deep-layer shear is expected less favorable than in areas to the south. This will likely keep any severe threat localized. ..Broyles.. 08/04/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1257 AM CDT Mon Aug 04 2025 Valid 051200Z - 061200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN PLAINS... ...SUMMARY... Thunderstorms associated with a threat for severe gusts and isolated large hail will be possible across parts of the central and northern Plains on Tuesday. ...Central and Northern Plains... A mid-level shortwave trough will move into the northern Plains on Tuesday. At the surface, a trough is forecast to sharpen during the day across the far western Dakotas. To the east of the trough, a moist airmass will be in place across much of the northern Plains. By afternoon, a north-to-south axis of moderate instability is forecast to develop to the east of the surface trough from western Nebraska northward into the western Dakotas. Within the moist sector, model consensus suggests that MLCAPE will peak in the 2500 to 3500 J/kg range, with the overall maximum located in western South Dakota. Low-level convergence will likely increase near and to the east of the surface trough, with scattered convective initiation expected near the trough in the late afternoon. These storms should spread eastward across west-central South Dakota and southwestern North Dakota during the late afternoon and early evening. A severe threat appears likely. Forecast soundings during the late afternoon across northwestern South Dakota have supercell wind profiles, with directional shear in the low to mid-levels, and 35 to 40 knots of 0-6 km shear. In addition, 700-500 mb lapse rates are forecast to be near 8 C/km. This environment would favor isolated large hail with rotating cells that remain discrete. A potential for severe wind gusts will also be possible, mainly with short line segments that form within a larger-scale cluster. The severe threat should persist into the mid evening, and could extend southward into northern Nebraska. However, severe threat magnitude is expected to be more isolated with southward extent, mainly due to more limited large-scale ascent. Further north into parts of north-central North Dakota and westward into northeast Montana, an isolated severe threat will be possible during the late afternoon and early evening. However, the combination of instability and deep-layer shear is expected less favorable than in areas to the south. This will likely keep any severe threat localized. ..Broyles.. 08/04/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1257 AM CDT Mon Aug 04 2025 Valid 051200Z - 061200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN PLAINS... ...SUMMARY... Thunderstorms associated with a threat for severe gusts and isolated large hail will be possible across parts of the central and northern Plains on Tuesday. ...Central and Northern Plains... A mid-level shortwave trough will move into the northern Plains on Tuesday. At the surface, a trough is forecast to sharpen during the day across the far western Dakotas. To the east of the trough, a moist airmass will be in place across much of the northern Plains. By afternoon, a north-to-south axis of moderate instability is forecast to develop to the east of the surface trough from western Nebraska northward into the western Dakotas. Within the moist sector, model consensus suggests that MLCAPE will peak in the 2500 to 3500 J/kg range, with the overall maximum located in western South Dakota. Low-level convergence will likely increase near and to the east of the surface trough, with scattered convective initiation expected near the trough in the late afternoon. These storms should spread eastward across west-central South Dakota and southwestern North Dakota during the late afternoon and early evening. A severe threat appears likely. Forecast soundings during the late afternoon across northwestern South Dakota have supercell wind profiles, with directional shear in the low to mid-levels, and 35 to 40 knots of 0-6 km shear. In addition, 700-500 mb lapse rates are forecast to be near 8 C/km. This environment would favor isolated large hail with rotating cells that remain discrete. A potential for severe wind gusts will also be possible, mainly with short line segments that form within a larger-scale cluster. The severe threat should persist into the mid evening, and could extend southward into northern Nebraska. However, severe threat magnitude is expected to be more isolated with southward extent, mainly due to more limited large-scale ascent. Further north into parts of north-central North Dakota and westward into northeast Montana, an isolated severe threat will be possible during the late afternoon and early evening. However, the combination of instability and deep-layer shear is expected less favorable than in areas to the south. This will likely keep any severe threat localized. ..Broyles.. 08/04/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1257 AM CDT Mon Aug 04 2025 Valid 051200Z - 061200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN PLAINS... ...SUMMARY... Thunderstorms associated with a threat for severe gusts and isolated large hail will be possible across parts of the central and northern Plains on Tuesday. ...Central and Northern Plains... A mid-level shortwave trough will move into the northern Plains on Tuesday. At the surface, a trough is forecast to sharpen during the day across the far western Dakotas. To the east of the trough, a moist airmass will be in place across much of the northern Plains. By afternoon, a north-to-south axis of moderate instability is forecast to develop to the east of the surface trough from western Nebraska northward into the western Dakotas. Within the moist sector, model consensus suggests that MLCAPE will peak in the 2500 to 3500 J/kg range, with the overall maximum located in western South Dakota. Low-level convergence will likely increase near and to the east of the surface trough, with scattered convective initiation expected near the trough in the late afternoon. These storms should spread eastward across west-central South Dakota and southwestern North Dakota during the late afternoon and early evening. A severe threat appears likely. Forecast soundings during the late afternoon across northwestern South Dakota have supercell wind profiles, with directional shear in the low to mid-levels, and 35 to 40 knots of 0-6 km shear. In addition, 700-500 mb lapse rates are forecast to be near 8 C/km. This environment would favor isolated large hail with rotating cells that remain discrete. A potential for severe wind gusts will also be possible, mainly with short line segments that form within a larger-scale cluster. The severe threat should persist into the mid evening, and could extend southward into northern Nebraska. However, severe threat magnitude is expected to be more isolated with southward extent, mainly due to more limited large-scale ascent. Further north into parts of north-central North Dakota and westward into northeast Montana, an isolated severe threat will be possible during the late afternoon and early evening. However, the combination of instability and deep-layer shear is expected less favorable than in areas to the south. This will likely keep any severe threat localized. ..Broyles.. 08/04/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0102 AM CDT Mon Aug 04 2025 Valid 041200Z - 051200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF FAR EASTERN WYOMING...SOUTHWEST SOUTH DAKOTA...WESTERN NEBRASKA AND NORTHEAST COLORADO/KANSAS... ...SUMMARY... Thunderstorms with severe gusts and hail will be possible today and tonight from parts of the northern Rockies into the Dakotas and central/southern High Plains. ..Central High Plains... Rather pronounced shortwave ridging is expected across the central High Plains through much of the day as troughing intensifies over the Northwest. With building heights aloft, synoptic forcing for ascent appears weak. Still, a subtle embedded perturbation should move eastward across the Rockies late in the afternoon, but it is unclear how much ascent this feature will support. Given the lack of stronger forcing for ascent, convective development over the central High Plains appears tied to diurnal heating and weak low-level upslope flow along the higher terrain of the Black Hills and eastern WY. This should favor widely scattered storm development within a hot and unstable air mass (MLCAPE 2500-3000 J/kg). Northwesterly flow aloft with elongated hodographs and 45-55 kt of effective shear will favor high-based supercells initially capable of hail (some significant) and damaging gusts before moving into more substantial low-level moisture farther east. With time, upscale growth appears likely given the strong outflow expected from the drier low-levels. Most CAM guidance shows one or more clusters evolving across western/central NE and northeast CO this evening. Aided by a 40+ kt low-level jet, continued upscale growth should support these clusters of strong to severe storms into the overnight hours where damaging winds will be possible. ...Southeast CO into the OK/TX Panhandles... Strong heating along a lee trough could support isolated thunderstorm development across the Raton Mesa and TX/OK Panhandles late this afternoon/evening. Large-scale forcing is not particularly strong beneath the building upper ridge. Still, model soundings show uncapped profiles with large buoyancy (3000+ J/kg MLCAPE) and 40-50 kt of effective shear. Should a storm develop it would likely be supercellular with the potential for hail and damaging gusts. A brief tornado is also possible as the low-level jet helps expand hodographs near sunset. The primary uncertainty for higher severe probabilities remains the limited forcing for ascent and the uncertainty on higher storm coverage. ...Montana... Model guidance shows a negatively tilted shortwave trough and mid-level jet streak moving across portions of the Northwest. This feature will track northeastward today, spreading broad ascent across the Northern Rockies. Steep low and mid-level lapse rates atop modest surface moisture (40s and 50s F dewpoints) will result in sufficient SBCAPE for scattered thunderstorm development over the mountains of central ID and western MT by mid-afternoon. Convection will become more numerous and spread into central and eventually eastern MT through the evening. Elongated hodographs (30-40 kt of bulk shear) will support a few organized clusters and rotating storms capable of damaging winds from strong downdrafts and some hail. The primary uncertainty for higher severe probabilities is the potential for limited buoyancy and lack of a stronger signal for consolidating outflow favoring higher damaging wind potential. ..Lyons.. 08/04/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0102 AM CDT Mon Aug 04 2025 Valid 041200Z - 051200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF FAR EASTERN WYOMING...SOUTHWEST SOUTH DAKOTA...WESTERN NEBRASKA AND NORTHEAST COLORADO/KANSAS... ...SUMMARY... Thunderstorms with severe gusts and hail will be possible today and tonight from parts of the northern Rockies into the Dakotas and central/southern High Plains. ..Central High Plains... Rather pronounced shortwave ridging is expected across the central High Plains through much of the day as troughing intensifies over the Northwest. With building heights aloft, synoptic forcing for ascent appears weak. Still, a subtle embedded perturbation should move eastward across the Rockies late in the afternoon, but it is unclear how much ascent this feature will support. Given the lack of stronger forcing for ascent, convective development over the central High Plains appears tied to diurnal heating and weak low-level upslope flow along the higher terrain of the Black Hills and eastern WY. This should favor widely scattered storm development within a hot and unstable air mass (MLCAPE 2500-3000 J/kg). Northwesterly flow aloft with elongated hodographs and 45-55 kt of effective shear will favor high-based supercells initially capable of hail (some significant) and damaging gusts before moving into more substantial low-level moisture farther east. With time, upscale growth appears likely given the strong outflow expected from the drier low-levels. Most CAM guidance shows one or more clusters evolving across western/central NE and northeast CO this evening. Aided by a 40+ kt low-level jet, continued upscale growth should support these clusters of strong to severe storms into the overnight hours where damaging winds will be possible. ...Southeast CO into the OK/TX Panhandles... Strong heating along a lee trough could support isolated thunderstorm development across the Raton Mesa and TX/OK Panhandles late this afternoon/evening. Large-scale forcing is not particularly strong beneath the building upper ridge. Still, model soundings show uncapped profiles with large buoyancy (3000+ J/kg MLCAPE) and 40-50 kt of effective shear. Should a storm develop it would likely be supercellular with the potential for hail and damaging gusts. A brief tornado is also possible as the low-level jet helps expand hodographs near sunset. The primary uncertainty for higher severe probabilities remains the limited forcing for ascent and the uncertainty on higher storm coverage. ...Montana... Model guidance shows a negatively tilted shortwave trough and mid-level jet streak moving across portions of the Northwest. This feature will track northeastward today, spreading broad ascent across the Northern Rockies. Steep low and mid-level lapse rates atop modest surface moisture (40s and 50s F dewpoints) will result in sufficient SBCAPE for scattered thunderstorm development over the mountains of central ID and western MT by mid-afternoon. Convection will become more numerous and spread into central and eventually eastern MT through the evening. Elongated hodographs (30-40 kt of bulk shear) will support a few organized clusters and rotating storms capable of damaging winds from strong downdrafts and some hail. The primary uncertainty for higher severe probabilities is the potential for limited buoyancy and lack of a stronger signal for consolidating outflow favoring higher damaging wind potential. ..Lyons.. 08/04/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0102 AM CDT Mon Aug 04 2025 Valid 041200Z - 051200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF FAR EASTERN WYOMING...SOUTHWEST SOUTH DAKOTA...WESTERN NEBRASKA AND NORTHEAST COLORADO/KANSAS... ...SUMMARY... Thunderstorms with severe gusts and hail will be possible today and tonight from parts of the northern Rockies into the Dakotas and central/southern High Plains. ..Central High Plains... Rather pronounced shortwave ridging is expected across the central High Plains through much of the day as troughing intensifies over the Northwest. With building heights aloft, synoptic forcing for ascent appears weak. Still, a subtle embedded perturbation should move eastward across the Rockies late in the afternoon, but it is unclear how much ascent this feature will support. Given the lack of stronger forcing for ascent, convective development over the central High Plains appears tied to diurnal heating and weak low-level upslope flow along the higher terrain of the Black Hills and eastern WY. This should favor widely scattered storm development within a hot and unstable air mass (MLCAPE 2500-3000 J/kg). Northwesterly flow aloft with elongated hodographs and 45-55 kt of effective shear will favor high-based supercells initially capable of hail (some significant) and damaging gusts before moving into more substantial low-level moisture farther east. With time, upscale growth appears likely given the strong outflow expected from the drier low-levels. Most CAM guidance shows one or more clusters evolving across western/central NE and northeast CO this evening. Aided by a 40+ kt low-level jet, continued upscale growth should support these clusters of strong to severe storms into the overnight hours where damaging winds will be possible. ...Southeast CO into the OK/TX Panhandles... Strong heating along a lee trough could support isolated thunderstorm development across the Raton Mesa and TX/OK Panhandles late this afternoon/evening. Large-scale forcing is not particularly strong beneath the building upper ridge. Still, model soundings show uncapped profiles with large buoyancy (3000+ J/kg MLCAPE) and 40-50 kt of effective shear. Should a storm develop it would likely be supercellular with the potential for hail and damaging gusts. A brief tornado is also possible as the low-level jet helps expand hodographs near sunset. The primary uncertainty for higher severe probabilities remains the limited forcing for ascent and the uncertainty on higher storm coverage. ...Montana... Model guidance shows a negatively tilted shortwave trough and mid-level jet streak moving across portions of the Northwest. This feature will track northeastward today, spreading broad ascent across the Northern Rockies. Steep low and mid-level lapse rates atop modest surface moisture (40s and 50s F dewpoints) will result in sufficient SBCAPE for scattered thunderstorm development over the mountains of central ID and western MT by mid-afternoon. Convection will become more numerous and spread into central and eventually eastern MT through the evening. Elongated hodographs (30-40 kt of bulk shear) will support a few organized clusters and rotating storms capable of damaging winds from strong downdrafts and some hail. The primary uncertainty for higher severe probabilities is the potential for limited buoyancy and lack of a stronger signal for consolidating outflow favoring higher damaging wind potential. ..Lyons.. 08/04/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0102 AM CDT Mon Aug 04 2025 Valid 041200Z - 051200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF FAR EASTERN WYOMING...SOUTHWEST SOUTH DAKOTA...WESTERN NEBRASKA AND NORTHEAST COLORADO/KANSAS... ...SUMMARY... Thunderstorms with severe gusts and hail will be possible today and tonight from parts of the northern Rockies into the Dakotas and central/southern High Plains. ..Central High Plains... Rather pronounced shortwave ridging is expected across the central High Plains through much of the day as troughing intensifies over the Northwest. With building heights aloft, synoptic forcing for ascent appears weak. Still, a subtle embedded perturbation should move eastward across the Rockies late in the afternoon, but it is unclear how much ascent this feature will support. Given the lack of stronger forcing for ascent, convective development over the central High Plains appears tied to diurnal heating and weak low-level upslope flow along the higher terrain of the Black Hills and eastern WY. This should favor widely scattered storm development within a hot and unstable air mass (MLCAPE 2500-3000 J/kg). Northwesterly flow aloft with elongated hodographs and 45-55 kt of effective shear will favor high-based supercells initially capable of hail (some significant) and damaging gusts before moving into more substantial low-level moisture farther east. With time, upscale growth appears likely given the strong outflow expected from the drier low-levels. Most CAM guidance shows one or more clusters evolving across western/central NE and northeast CO this evening. Aided by a 40+ kt low-level jet, continued upscale growth should support these clusters of strong to severe storms into the overnight hours where damaging winds will be possible. ...Southeast CO into the OK/TX Panhandles... Strong heating along a lee trough could support isolated thunderstorm development across the Raton Mesa and TX/OK Panhandles late this afternoon/evening. Large-scale forcing is not particularly strong beneath the building upper ridge. Still, model soundings show uncapped profiles with large buoyancy (3000+ J/kg MLCAPE) and 40-50 kt of effective shear. Should a storm develop it would likely be supercellular with the potential for hail and damaging gusts. A brief tornado is also possible as the low-level jet helps expand hodographs near sunset. The primary uncertainty for higher severe probabilities remains the limited forcing for ascent and the uncertainty on higher storm coverage. ...Montana... Model guidance shows a negatively tilted shortwave trough and mid-level jet streak moving across portions of the Northwest. This feature will track northeastward today, spreading broad ascent across the Northern Rockies. Steep low and mid-level lapse rates atop modest surface moisture (40s and 50s F dewpoints) will result in sufficient SBCAPE for scattered thunderstorm development over the mountains of central ID and western MT by mid-afternoon. Convection will become more numerous and spread into central and eventually eastern MT through the evening. Elongated hodographs (30-40 kt of bulk shear) will support a few organized clusters and rotating storms capable of damaging winds from strong downdrafts and some hail. The primary uncertainty for higher severe probabilities is the potential for limited buoyancy and lack of a stronger signal for consolidating outflow favoring higher damaging wind potential. ..Lyons.. 08/04/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0102 AM CDT Mon Aug 04 2025 Valid 041200Z - 051200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF FAR EASTERN WYOMING...SOUTHWEST SOUTH DAKOTA...WESTERN NEBRASKA AND NORTHEAST COLORADO/KANSAS... ...SUMMARY... Thunderstorms with severe gusts and hail will be possible today and tonight from parts of the northern Rockies into the Dakotas and central/southern High Plains. ..Central High Plains... Rather pronounced shortwave ridging is expected across the central High Plains through much of the day as troughing intensifies over the Northwest. With building heights aloft, synoptic forcing for ascent appears weak. Still, a subtle embedded perturbation should move eastward across the Rockies late in the afternoon, but it is unclear how much ascent this feature will support. Given the lack of stronger forcing for ascent, convective development over the central High Plains appears tied to diurnal heating and weak low-level upslope flow along the higher terrain of the Black Hills and eastern WY. This should favor widely scattered storm development within a hot and unstable air mass (MLCAPE 2500-3000 J/kg). Northwesterly flow aloft with elongated hodographs and 45-55 kt of effective shear will favor high-based supercells initially capable of hail (some significant) and damaging gusts before moving into more substantial low-level moisture farther east. With time, upscale growth appears likely given the strong outflow expected from the drier low-levels. Most CAM guidance shows one or more clusters evolving across western/central NE and northeast CO this evening. Aided by a 40+ kt low-level jet, continued upscale growth should support these clusters of strong to severe storms into the overnight hours where damaging winds will be possible. ...Southeast CO into the OK/TX Panhandles... Strong heating along a lee trough could support isolated thunderstorm development across the Raton Mesa and TX/OK Panhandles late this afternoon/evening. Large-scale forcing is not particularly strong beneath the building upper ridge. Still, model soundings show uncapped profiles with large buoyancy (3000+ J/kg MLCAPE) and 40-50 kt of effective shear. Should a storm develop it would likely be supercellular with the potential for hail and damaging gusts. A brief tornado is also possible as the low-level jet helps expand hodographs near sunset. The primary uncertainty for higher severe probabilities remains the limited forcing for ascent and the uncertainty on higher storm coverage. ...Montana... Model guidance shows a negatively tilted shortwave trough and mid-level jet streak moving across portions of the Northwest. This feature will track northeastward today, spreading broad ascent across the Northern Rockies. Steep low and mid-level lapse rates atop modest surface moisture (40s and 50s F dewpoints) will result in sufficient SBCAPE for scattered thunderstorm development over the mountains of central ID and western MT by mid-afternoon. Convection will become more numerous and spread into central and eventually eastern MT through the evening. Elongated hodographs (30-40 kt of bulk shear) will support a few organized clusters and rotating storms capable of damaging winds from strong downdrafts and some hail. The primary uncertainty for higher severe probabilities is the potential for limited buoyancy and lack of a stronger signal for consolidating outflow favoring higher damaging wind potential. ..Lyons.. 08/04/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0102 AM CDT Mon Aug 04 2025 Valid 041200Z - 051200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF FAR EASTERN WYOMING...SOUTHWEST SOUTH DAKOTA...WESTERN NEBRASKA AND NORTHEAST COLORADO/KANSAS... ...SUMMARY... Thunderstorms with severe gusts and hail will be possible today and tonight from parts of the northern Rockies into the Dakotas and central/southern High Plains. ..Central High Plains... Rather pronounced shortwave ridging is expected across the central High Plains through much of the day as troughing intensifies over the Northwest. With building heights aloft, synoptic forcing for ascent appears weak. Still, a subtle embedded perturbation should move eastward across the Rockies late in the afternoon, but it is unclear how much ascent this feature will support. Given the lack of stronger forcing for ascent, convective development over the central High Plains appears tied to diurnal heating and weak low-level upslope flow along the higher terrain of the Black Hills and eastern WY. This should favor widely scattered storm development within a hot and unstable air mass (MLCAPE 2500-3000 J/kg). Northwesterly flow aloft with elongated hodographs and 45-55 kt of effective shear will favor high-based supercells initially capable of hail (some significant) and damaging gusts before moving into more substantial low-level moisture farther east. With time, upscale growth appears likely given the strong outflow expected from the drier low-levels. Most CAM guidance shows one or more clusters evolving across western/central NE and northeast CO this evening. Aided by a 40+ kt low-level jet, continued upscale growth should support these clusters of strong to severe storms into the overnight hours where damaging winds will be possible. ...Southeast CO into the OK/TX Panhandles... Strong heating along a lee trough could support isolated thunderstorm development across the Raton Mesa and TX/OK Panhandles late this afternoon/evening. Large-scale forcing is not particularly strong beneath the building upper ridge. Still, model soundings show uncapped profiles with large buoyancy (3000+ J/kg MLCAPE) and 40-50 kt of effective shear. Should a storm develop it would likely be supercellular with the potential for hail and damaging gusts. A brief tornado is also possible as the low-level jet helps expand hodographs near sunset. The primary uncertainty for higher severe probabilities remains the limited forcing for ascent and the uncertainty on higher storm coverage. ...Montana... Model guidance shows a negatively tilted shortwave trough and mid-level jet streak moving across portions of the Northwest. This feature will track northeastward today, spreading broad ascent across the Northern Rockies. Steep low and mid-level lapse rates atop modest surface moisture (40s and 50s F dewpoints) will result in sufficient SBCAPE for scattered thunderstorm development over the mountains of central ID and western MT by mid-afternoon. Convection will become more numerous and spread into central and eventually eastern MT through the evening. Elongated hodographs (30-40 kt of bulk shear) will support a few organized clusters and rotating storms capable of damaging winds from strong downdrafts and some hail. The primary uncertainty for higher severe probabilities is the potential for limited buoyancy and lack of a stronger signal for consolidating outflow favoring higher damaging wind potential. ..Lyons.. 08/04/2025 Read more

534
ABNT20 KNHC 040533
TWOAT

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
200 AM EDT Mon Aug 4 2025

For the North Atlantic...Caribbean Sea and the Gulf of America:

Active Systems:
The National Hurricane Center is issuing advisories on newly formed
Tropical Storm Dexter, located over the western Atlantic Ocean.

Central Tropical Atlantic:
A tropical wave is forecast to move off the west coast of Africa
later today. Thereafter, some gradual development of the wave is
possible, and a tropical depression could form late this week while
it moves generally west-northwestward across the central tropical
Atlantic.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...medium...50 percent.

Off the Southeastern United States:
A broad area of low pressure is forecast to form in a couple of
days a few hundred miles off the coast of the southeastern United
States. Some gradual development of this system is possible during
the middle or latter part of the week as the system drifts to the
west or northwest.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...low...30 percent.

&&

Public Advisories on Tropical Storm Dexter are issued under WMO
header WTNT34 KNHC and under AWIPS header MIATCPAT4.
Forecast/Advisories on Tropical Storm Dexter are issued under WMO
header WTNT24 KNHC and under AWIPS header MIATCMAT4.

$$
Forecaster Blake