Tropical Storm Juliette Forecast Advisory Number 3

1 month ago
Issued at 0900 UTC MON AUG 25 2025 ZCZC MIATCMEP5 ALL TTAA00 KNHC DDHHMM TROPICAL STORM JULIETTE FORECAST/ADVISORY NUMBER 3 NWS NATIONAL HURRICANE CENTER MIAMI FL EP102025 0900 UTC MON AUG 25 2025 TROPICAL STORM CENTER LOCATED NEAR 16.8N 111.8W AT 25/0900Z POSITION ACCURATE WITHIN 30 NM PRESENT MOVEMENT TOWARD THE WEST-NORTHWEST OR 290 DEGREES AT 11 KT ESTIMATED MINIMUM CENTRAL PRESSURE 1003 MB MAX SUSTAINED WINDS 35 KT WITH GUSTS TO 45 KT. 34 KT....... 50NE 0SE 0SW 40NW. WINDS AND SEAS VARY GREATLY IN EACH QUADRANT. RADII IN NAUTICAL MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT. REPEAT...CENTER LOCATED NEAR 16.8N 111.8W AT 25/0900Z AT 25/0600Z CENTER WAS LOCATED NEAR 16.5N 111.3W FORECAST VALID 25/1800Z 17.5N 113.5W MAX WIND 40 KT...GUSTS 50 KT. 34 KT... 50NE 30SE 0SW 50NW. FORECAST VALID 26/0600Z 18.4N 115.5W MAX WIND 45 KT...GUSTS 55 KT. 34 KT... 60NE 30SE 0SW 50NW. FORECAST VALID 26/1800Z 19.4N 117.3W MAX WIND 55 KT...GUSTS 65 KT. 50 KT... 20NE 0SE 0SW 0NW. 34 KT... 60NE 40SE 30SW 40NW. FORECAST VALID 27/0600Z 20.6N 118.9W MAX WIND 55 KT...GUSTS 65 KT. 50 KT... 20NE 20SE 0SW 0NW. 34 KT... 60NE 40SE 30SW 50NW. FORECAST VALID 27/1800Z 21.9N 120.2W MAX WIND 45 KT...GUSTS 55 KT. 34 KT... 60NE 40SE 30SW 50NW. FORECAST VALID 28/0600Z 23.2N 121.1W MAX WIND 35 KT...GUSTS 45 KT. 34 KT... 50NE 30SE 0SW 30NW. EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 100 NM ON DAY 4 AND 125 NM ON DAY 5...AND FOR INTENSITY NEAR 15 KT EACH DAY OUTLOOK VALID 29/0600Z 25.0N 122.1W...POST-TROP/REMNT LOW MAX WIND 25 KT...GUSTS 35 KT. OUTLOOK VALID 30/0600Z 25.9N 122.9W...POST-TROP/REMNT LOW MAX WIND 20 KT...GUSTS 30 KT. REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 16.8N 111.8W NEXT ADVISORY AT 25/1500Z $$ FORECASTER HAGEN NNNN
NHC Webmaster

SPC Aug 25, 2025 0730 UTC Day 3 Severe Thunderstorm Outlook

1 month ago
SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0214 AM CDT Mon Aug 25 2025 Valid 271200Z - 281200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The potential for severe storms appears to be low across the continental U.S. for Wednesday and Wednesday night. ...DISCUSSION... A mid-level cyclonic flow pattern is forecast to be maintained over much of the eastern half of the nation on Wednesday, as a shortwave ridge stays in place over the southern and central Rockies. At the surface, a large area of high pressure will remain centered on the mid Mississippi Valley. Along the western periphery of this post-frontal airmass, low-level moisture return is forecast over the southern plains on Wednesday. An axis of instability appears likely to develop by late afternoon along the northern edge of the returning low-level moisture from western Oklahoma into southwest Kansas. As an 850 mb jet strengthens during the evening, isolated to scattered thunderstorms are expected to develop from near this instability axis eastward across parts of central and eastern Kansas. It appears this convection will remain non-severe, and may be primarily elevated in nature. Elsewhere across the continental U.S., no severe threat is expected Wednesday or Wednesday night. ..Broyles.. 08/25/2025 Read more

SPC Aug 25, 2025 0730 UTC Day 3 Severe Thunderstorm Outlook

1 month ago
SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0214 AM CDT Mon Aug 25 2025 Valid 271200Z - 281200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The potential for severe storms appears to be low across the continental U.S. for Wednesday and Wednesday night. ...DISCUSSION... A mid-level cyclonic flow pattern is forecast to be maintained over much of the eastern half of the nation on Wednesday, as a shortwave ridge stays in place over the southern and central Rockies. At the surface, a large area of high pressure will remain centered on the mid Mississippi Valley. Along the western periphery of this post-frontal airmass, low-level moisture return is forecast over the southern plains on Wednesday. An axis of instability appears likely to develop by late afternoon along the northern edge of the returning low-level moisture from western Oklahoma into southwest Kansas. As an 850 mb jet strengthens during the evening, isolated to scattered thunderstorms are expected to develop from near this instability axis eastward across parts of central and eastern Kansas. It appears this convection will remain non-severe, and may be primarily elevated in nature. Elsewhere across the continental U.S., no severe threat is expected Wednesday or Wednesday night. ..Broyles.. 08/25/2025 Read more

SPC Aug 25, 2025 0730 UTC Day 3 Severe Thunderstorm Outlook

1 month ago
SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0214 AM CDT Mon Aug 25 2025 Valid 271200Z - 281200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The potential for severe storms appears to be low across the continental U.S. for Wednesday and Wednesday night. ...DISCUSSION... A mid-level cyclonic flow pattern is forecast to be maintained over much of the eastern half of the nation on Wednesday, as a shortwave ridge stays in place over the southern and central Rockies. At the surface, a large area of high pressure will remain centered on the mid Mississippi Valley. Along the western periphery of this post-frontal airmass, low-level moisture return is forecast over the southern plains on Wednesday. An axis of instability appears likely to develop by late afternoon along the northern edge of the returning low-level moisture from western Oklahoma into southwest Kansas. As an 850 mb jet strengthens during the evening, isolated to scattered thunderstorms are expected to develop from near this instability axis eastward across parts of central and eastern Kansas. It appears this convection will remain non-severe, and may be primarily elevated in nature. Elsewhere across the continental U.S., no severe threat is expected Wednesday or Wednesday night. ..Broyles.. 08/25/2025 Read more

SPC Day 2 Fire Weather Outlook

1 month ago
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0159 AM CDT Mon Aug 25 2025 Valid 261200Z - 271200Z ...Synopsis... Well-established monsoonal moisture will remain in place across the Northwest on Tuesday. Boundary-layer mixing beneath the rich midlevel moisture will contribute to sufficient buoyancy for diurnally driven high-based thunderstorms along the Cascades, where fuels are dry. Inverted-V profiles and 0.80-0.90 inch PW will favor a mix of wet/dry thunderstorms capable of producing gusty/erratic outflow winds and lightning-induced ignitions. A continuation of wet/dry thunderstorms are also expected across parts of northern CA and the northern Rockies, though uncertainty regarding fuel receptiveness in these areas precludes highlights at this time. ..Weinman.. 08/25/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook

1 month ago
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0159 AM CDT Mon Aug 25 2025 Valid 261200Z - 271200Z ...Synopsis... Well-established monsoonal moisture will remain in place across the Northwest on Tuesday. Boundary-layer mixing beneath the rich midlevel moisture will contribute to sufficient buoyancy for diurnally driven high-based thunderstorms along the Cascades, where fuels are dry. Inverted-V profiles and 0.80-0.90 inch PW will favor a mix of wet/dry thunderstorms capable of producing gusty/erratic outflow winds and lightning-induced ignitions. A continuation of wet/dry thunderstorms are also expected across parts of northern CA and the northern Rockies, though uncertainty regarding fuel receptiveness in these areas precludes highlights at this time. ..Weinman.. 08/25/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook

1 month ago
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0159 AM CDT Mon Aug 25 2025 Valid 261200Z - 271200Z ...Synopsis... Well-established monsoonal moisture will remain in place across the Northwest on Tuesday. Boundary-layer mixing beneath the rich midlevel moisture will contribute to sufficient buoyancy for diurnally driven high-based thunderstorms along the Cascades, where fuels are dry. Inverted-V profiles and 0.80-0.90 inch PW will favor a mix of wet/dry thunderstorms capable of producing gusty/erratic outflow winds and lightning-induced ignitions. A continuation of wet/dry thunderstorms are also expected across parts of northern CA and the northern Rockies, though uncertainty regarding fuel receptiveness in these areas precludes highlights at this time. ..Weinman.. 08/25/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook

1 month ago
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0159 AM CDT Mon Aug 25 2025 Valid 261200Z - 271200Z ...Synopsis... Well-established monsoonal moisture will remain in place across the Northwest on Tuesday. Boundary-layer mixing beneath the rich midlevel moisture will contribute to sufficient buoyancy for diurnally driven high-based thunderstorms along the Cascades, where fuels are dry. Inverted-V profiles and 0.80-0.90 inch PW will favor a mix of wet/dry thunderstorms capable of producing gusty/erratic outflow winds and lightning-induced ignitions. A continuation of wet/dry thunderstorms are also expected across parts of northern CA and the northern Rockies, though uncertainty regarding fuel receptiveness in these areas precludes highlights at this time. ..Weinman.. 08/25/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook

1 month ago
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0159 AM CDT Mon Aug 25 2025 Valid 251200Z - 261200Z ...Synopsis... Along the northern periphery of a midlevel ridge centered on the Four Corners region, monsoonal moisture atop a warm/dry boundary layer will support isolated to widely scattered high-based thunderstorms across the Northwest -- with a focus over the higher terrain. Over the Cascades, PW values of 0.70-0.90 inches will favor a mix of wet/dry thunderstorms over receptive fuels, posing a risk of lightning-induced ignitions and gusty/erratic outflow winds. Thunderstorm potential is more uncertain over the WA Cascades owing to limited monsoonal moisture compared to areas farther south. Nevertheless, any storms that do form will be dry and pose a risk of new starts. A continuation of wet/dry thunderstorms are also expected across northern CA, though recent rainfall and 1+ inch PW cast uncertainty on overall ignition potential. For central ID into southwest MT, mixed wet/dry thunderstorms may pose a short-term risk of lightning-induced ignitions; however, increasing rainfall in the coming days should limit the overall risk. ..Weinman.. 08/25/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook

1 month ago
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0159 AM CDT Mon Aug 25 2025 Valid 251200Z - 261200Z ...Synopsis... Along the northern periphery of a midlevel ridge centered on the Four Corners region, monsoonal moisture atop a warm/dry boundary layer will support isolated to widely scattered high-based thunderstorms across the Northwest -- with a focus over the higher terrain. Over the Cascades, PW values of 0.70-0.90 inches will favor a mix of wet/dry thunderstorms over receptive fuels, posing a risk of lightning-induced ignitions and gusty/erratic outflow winds. Thunderstorm potential is more uncertain over the WA Cascades owing to limited monsoonal moisture compared to areas farther south. Nevertheless, any storms that do form will be dry and pose a risk of new starts. A continuation of wet/dry thunderstorms are also expected across northern CA, though recent rainfall and 1+ inch PW cast uncertainty on overall ignition potential. For central ID into southwest MT, mixed wet/dry thunderstorms may pose a short-term risk of lightning-induced ignitions; however, increasing rainfall in the coming days should limit the overall risk. ..Weinman.. 08/25/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook

1 month ago
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0159 AM CDT Mon Aug 25 2025 Valid 251200Z - 261200Z ...Synopsis... Along the northern periphery of a midlevel ridge centered on the Four Corners region, monsoonal moisture atop a warm/dry boundary layer will support isolated to widely scattered high-based thunderstorms across the Northwest -- with a focus over the higher terrain. Over the Cascades, PW values of 0.70-0.90 inches will favor a mix of wet/dry thunderstorms over receptive fuels, posing a risk of lightning-induced ignitions and gusty/erratic outflow winds. Thunderstorm potential is more uncertain over the WA Cascades owing to limited monsoonal moisture compared to areas farther south. Nevertheless, any storms that do form will be dry and pose a risk of new starts. A continuation of wet/dry thunderstorms are also expected across northern CA, though recent rainfall and 1+ inch PW cast uncertainty on overall ignition potential. For central ID into southwest MT, mixed wet/dry thunderstorms may pose a short-term risk of lightning-induced ignitions; however, increasing rainfall in the coming days should limit the overall risk. ..Weinman.. 08/25/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook

1 month ago
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0159 AM CDT Mon Aug 25 2025 Valid 251200Z - 261200Z ...Synopsis... Along the northern periphery of a midlevel ridge centered on the Four Corners region, monsoonal moisture atop a warm/dry boundary layer will support isolated to widely scattered high-based thunderstorms across the Northwest -- with a focus over the higher terrain. Over the Cascades, PW values of 0.70-0.90 inches will favor a mix of wet/dry thunderstorms over receptive fuels, posing a risk of lightning-induced ignitions and gusty/erratic outflow winds. Thunderstorm potential is more uncertain over the WA Cascades owing to limited monsoonal moisture compared to areas farther south. Nevertheless, any storms that do form will be dry and pose a risk of new starts. A continuation of wet/dry thunderstorms are also expected across northern CA, though recent rainfall and 1+ inch PW cast uncertainty on overall ignition potential. For central ID into southwest MT, mixed wet/dry thunderstorms may pose a short-term risk of lightning-induced ignitions; however, increasing rainfall in the coming days should limit the overall risk. ..Weinman.. 08/25/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Aug 25, 2025 0600 UTC Day 2 Convective Outlook

1 month ago
SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1240 AM CDT Mon Aug 25 2025 Valid 261200Z - 271200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe storms are not expected across the continental U.S. on Tuesday or Tuesday night. ...DISCUSSION... At mid-levels, a large-scale trough will move across the eastern U.S. on Tuesday, as northwesterly flow remains over much of the central states. At the surface, a large area of high pressure will be anchored over much of the eastern two-thirds of the nation. Within this post-frontal airmass, surface dewpoints are expected to be in the 60s over much of Texas and Louisiana. During the day as surface temperatures warm, thunderstorms will be possible over parts of the southern Plains and Gulf Coast states. Thunderstorms will also be possible over parts of the southern and central Rockies. In these areas, instability is forecast to remain very weak, suggesting the severe potential will be limited. ..Broyles.. 08/25/2025 Read more

SPC Aug 25, 2025 0600 UTC Day 2 Convective Outlook

1 month ago
SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1240 AM CDT Mon Aug 25 2025 Valid 261200Z - 271200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe storms are not expected across the continental U.S. on Tuesday or Tuesday night. ...DISCUSSION... At mid-levels, a large-scale trough will move across the eastern U.S. on Tuesday, as northwesterly flow remains over much of the central states. At the surface, a large area of high pressure will be anchored over much of the eastern two-thirds of the nation. Within this post-frontal airmass, surface dewpoints are expected to be in the 60s over much of Texas and Louisiana. During the day as surface temperatures warm, thunderstorms will be possible over parts of the southern Plains and Gulf Coast states. Thunderstorms will also be possible over parts of the southern and central Rockies. In these areas, instability is forecast to remain very weak, suggesting the severe potential will be limited. ..Broyles.. 08/25/2025 Read more

SPC Aug 25, 2025 0600 UTC Day 2 Convective Outlook

1 month ago
SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1240 AM CDT Mon Aug 25 2025 Valid 261200Z - 271200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe storms are not expected across the continental U.S. on Tuesday or Tuesday night. ...DISCUSSION... At mid-levels, a large-scale trough will move across the eastern U.S. on Tuesday, as northwesterly flow remains over much of the central states. At the surface, a large area of high pressure will be anchored over much of the eastern two-thirds of the nation. Within this post-frontal airmass, surface dewpoints are expected to be in the 60s over much of Texas and Louisiana. During the day as surface temperatures warm, thunderstorms will be possible over parts of the southern Plains and Gulf Coast states. Thunderstorms will also be possible over parts of the southern and central Rockies. In these areas, instability is forecast to remain very weak, suggesting the severe potential will be limited. ..Broyles.. 08/25/2025 Read more

SPC Aug 25, 2025 0600 UTC Day 2 Convective Outlook

1 month ago
SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1240 AM CDT Mon Aug 25 2025 Valid 261200Z - 271200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe storms are not expected across the continental U.S. on Tuesday or Tuesday night. ...DISCUSSION... At mid-levels, a large-scale trough will move across the eastern U.S. on Tuesday, as northwesterly flow remains over much of the central states. At the surface, a large area of high pressure will be anchored over much of the eastern two-thirds of the nation. Within this post-frontal airmass, surface dewpoints are expected to be in the 60s over much of Texas and Louisiana. During the day as surface temperatures warm, thunderstorms will be possible over parts of the southern Plains and Gulf Coast states. Thunderstorms will also be possible over parts of the southern and central Rockies. In these areas, instability is forecast to remain very weak, suggesting the severe potential will be limited. ..Broyles.. 08/25/2025 Read more

SPC Aug 25, 2025 0600 UTC Day 1 Convective Outlook

1 month ago
SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1259 AM CDT Mon Aug 25 2025 Valid 251200Z - 261200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTHERN ARIZONA... ...SUMMARY... Isolated severe gusts are possible over parts of south-central Arizona this afternoon. Otherwise, potential for severe storms is low across the remainder of the continental U.S. ...Synopsis... A large upper-level trough will continue to amplify across the eastern CONUS today. High pressure, currently analyzed across the northern Plains early this morning will expand slowly southward through the day which will push the polar front off the Atlantic coast and perhaps into the Gulf. A persistent upper-level ridge will exist across the Southwest and into the Great Basin/Rocky Mountains. Beneath this ridge, a continued monsoon push will result in widespread thunderstorm activity this afternoon/evening. ...Southern Arizona... Monsoon thunderstorms are forecast to develop this afternoon/evening across much of the Southwest amid weak to moderate instability (1000-1500 J/kg MLCAPE) as temperatures cool aloft. A belt of stronger mid-level southeasterly flow (20 to 25 knots) is forecast to overspread the region and provide ample shear for some multicell storm clusters. Initial storms which are expected to form across the higher terrain in southeast Arizona may result in congealing outflow with a damaging wind threat as storms move generally northwestward through the evening. ..Bentley/Weinman.. 08/25/2025 Read more

SPC Aug 25, 2025 0600 UTC Day 1 Convective Outlook

1 month ago
SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1259 AM CDT Mon Aug 25 2025 Valid 251200Z - 261200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTHERN ARIZONA... ...SUMMARY... Isolated severe gusts are possible over parts of south-central Arizona this afternoon. Otherwise, potential for severe storms is low across the remainder of the continental U.S. ...Synopsis... A large upper-level trough will continue to amplify across the eastern CONUS today. High pressure, currently analyzed across the northern Plains early this morning will expand slowly southward through the day which will push the polar front off the Atlantic coast and perhaps into the Gulf. A persistent upper-level ridge will exist across the Southwest and into the Great Basin/Rocky Mountains. Beneath this ridge, a continued monsoon push will result in widespread thunderstorm activity this afternoon/evening. ...Southern Arizona... Monsoon thunderstorms are forecast to develop this afternoon/evening across much of the Southwest amid weak to moderate instability (1000-1500 J/kg MLCAPE) as temperatures cool aloft. A belt of stronger mid-level southeasterly flow (20 to 25 knots) is forecast to overspread the region and provide ample shear for some multicell storm clusters. Initial storms which are expected to form across the higher terrain in southeast Arizona may result in congealing outflow with a damaging wind threat as storms move generally northwestward through the evening. ..Bentley/Weinman.. 08/25/2025 Read more

SPC Aug 25, 2025 0600 UTC Day 1 Convective Outlook

1 month ago
SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1259 AM CDT Mon Aug 25 2025 Valid 251200Z - 261200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTHERN ARIZONA... ...SUMMARY... Isolated severe gusts are possible over parts of south-central Arizona this afternoon. Otherwise, potential for severe storms is low across the remainder of the continental U.S. ...Synopsis... A large upper-level trough will continue to amplify across the eastern CONUS today. High pressure, currently analyzed across the northern Plains early this morning will expand slowly southward through the day which will push the polar front off the Atlantic coast and perhaps into the Gulf. A persistent upper-level ridge will exist across the Southwest and into the Great Basin/Rocky Mountains. Beneath this ridge, a continued monsoon push will result in widespread thunderstorm activity this afternoon/evening. ...Southern Arizona... Monsoon thunderstorms are forecast to develop this afternoon/evening across much of the Southwest amid weak to moderate instability (1000-1500 J/kg MLCAPE) as temperatures cool aloft. A belt of stronger mid-level southeasterly flow (20 to 25 knots) is forecast to overspread the region and provide ample shear for some multicell storm clusters. Initial storms which are expected to form across the higher terrain in southeast Arizona may result in congealing outflow with a damaging wind threat as storms move generally northwestward through the evening. ..Bentley/Weinman.. 08/25/2025 Read more

SPC Aug 25, 2025 0600 UTC Day 1 Convective Outlook

1 month ago
SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1259 AM CDT Mon Aug 25 2025 Valid 251200Z - 261200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTHERN ARIZONA... ...SUMMARY... Isolated severe gusts are possible over parts of south-central Arizona this afternoon. Otherwise, potential for severe storms is low across the remainder of the continental U.S. ...Synopsis... A large upper-level trough will continue to amplify across the eastern CONUS today. High pressure, currently analyzed across the northern Plains early this morning will expand slowly southward through the day which will push the polar front off the Atlantic coast and perhaps into the Gulf. A persistent upper-level ridge will exist across the Southwest and into the Great Basin/Rocky Mountains. Beneath this ridge, a continued monsoon push will result in widespread thunderstorm activity this afternoon/evening. ...Southern Arizona... Monsoon thunderstorms are forecast to develop this afternoon/evening across much of the Southwest amid weak to moderate instability (1000-1500 J/kg MLCAPE) as temperatures cool aloft. A belt of stronger mid-level southeasterly flow (20 to 25 knots) is forecast to overspread the region and provide ample shear for some multicell storm clusters. Initial storms which are expected to form across the higher terrain in southeast Arizona may result in congealing outflow with a damaging wind threat as storms move generally northwestward through the evening. ..Bentley/Weinman.. 08/25/2025 Read more