Tropical Storm Ivo Forecast Discussion Number 8

2 weeks 2 days ago
Issued at 800 AM MST Fri Aug 08 2025 000 WTPZ44 KNHC 081436 TCDEP4 Tropical Storm Ivo Discussion Number 8 NWS National Hurricane Center Miami FL EP092025 800 AM MST Fri Aug 08 2025 Ivo's satellite presentation hasn't changed much since the last advisory. The center appears to be embedded beneath the northern side of the Central Dense Overcast, with one small convective band forming on the northwestern side of the circulation. The Dvorak estimate from TAFB increased to T3.5/55 kt, however the SAB estimate and all objective guidance is much lower. Therefore, the current intensity is held at 50 kt. Ivo is slowing down and now has a west-northwestward initial motion at 295/14 kt. Strong mid-level ridging to the north is expected to be the main driver for the entirety of the forecast, keeping Ivo on a westward or west-northwestward trajectory but at a slower forward speed. No significant changes were made to the official track forecast. The more complicated part of the forecast is the intensity. Ivo is expected to remain over waters warmer than 26 degrees Celsius and in a moist environment with divergence aloft for the next 24 hours or so. Because of that, the NHC intensity forecast continues to show some strengthening through tonight. The forecast no longer explicitly shows Ivo becoming a hurricane, but that is still a small possibility, especially if Ivo is currently stronger than is being estimated. Beginning in about 36 hours, colder ocean temperatures, a more stable environment, and less divergence aloft should cause the storm to weaken. Some of the models differ significantly on exactly how quick that weakening will be. For example, the GFS maintains tropical-storm-force winds for at least the next 3 days, while the ECWMF degenerates Ivo into a remnant low in about 24 hours. As a compromise, the NHC forecast shows Ivo becoming post-tropical by 60 hours, with dissipation by day 5, if not sooner. FORECAST POSITIONS AND MAX WINDS INIT 08/1500Z 20.7N 110.1W 50 KT 60 MPH 12H 09/0000Z 21.1N 111.7W 55 KT 65 MPH 24H 09/1200Z 21.3N 113.4W 60 KT 70 MPH 36H 10/0000Z 21.3N 114.9W 55 KT 65 MPH 48H 10/1200Z 21.5N 116.6W 45 KT 50 MPH 60H 11/0000Z 21.9N 118.3W 35 KT 40 MPH...POST-TROPICAL 72H 11/1200Z 22.0N 120.0W 30 KT 35 MPH...POST-TROP/REMNT LOW 96H 12/1200Z 22.0N 124.5W 25 KT 30 MPH...POST-TROP/REMNT LOW 120H 13/1200Z...DISSIPATED $$ Forecaster Berg
NHC Webmaster

Tropical Storm Henriette Forecast Advisory Number 18

2 weeks 2 days ago
Issued at 1500 UTC FRI AUG 08 2025 ZCZC HFOTCMCP3 ALL TTAA00 PHFO DDHHMM TROPICAL STORM HENRIETTE FORECAST/ADVISORY NUMBER 18 NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI EP082025 ISSUED BY NWS NATIONAL HURRICANE CENTER MIAMI FL 1500 UTC FRI AUG 08 2025 TROPICAL STORM CENTER LOCATED NEAR 19.7N 141.5W AT 08/1500Z POSITION ACCURATE WITHIN 30 NM PRESENT MOVEMENT TOWARD THE WEST OR 280 DEGREES AT 15 KT ESTIMATED MINIMUM CENTRAL PRESSURE 1008 MB MAX SUSTAINED WINDS 35 KT WITH GUSTS TO 45 KT. 34 KT....... 50NE 0SE 0SW 50NW. 4 M SEAS.... 90NE 60SE 60SW 60NW. 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 19.7N 141.5W AT 08/1500Z AT 08/1200Z CENTER WAS LOCATED NEAR 19.5N 140.8W FORECAST VALID 09/0000Z 20.3N 143.7W...POST-TROP/REMNT LOW MAX WIND 30 KT...GUSTS 40 KT. FORECAST VALID 09/1200Z 21.3N 146.3W...POST-TROP/REMNT LOW MAX WIND 30 KT...GUSTS 40 KT. FORECAST VALID 10/0000Z 22.6N 148.7W...TROPICAL CYCLONE MAX WIND 35 KT...GUSTS 45 KT. 34 KT... 50NE 0SE 0SW 40NW. FORECAST VALID 10/1200Z 24.1N 150.9W MAX WIND 45 KT...GUSTS 55 KT. 34 KT... 60NE 30SE 0SW 50NW. FORECAST VALID 11/0000Z 25.9N 153.2W MAX WIND 55 KT...GUSTS 65 KT. 50 KT... 25NE 20SE 0SW 20NW. 34 KT... 70NE 40SE 30SW 60NW. FORECAST VALID 11/1200Z 27.9N 155.7W MAX WIND 65 KT...GUSTS 80 KT. 64 KT... 15NE 0SE 0SW 0NW. 50 KT... 30NE 25SE 10SW 20NW. 34 KT... 70NE 50SE 30SW 60NW. EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 150 NM ON DAY 4 AND 200 NM ON DAY 5...AND FOR INTENSITY NEAR 20 KT EACH DAY OUTLOOK VALID 12/1200Z 32.3N 160.4W MAX WIND 65 KT...GUSTS 80 KT. 50 KT... 35NE 30SE 10SW 25NW. 34 KT... 70NE 60SE 40SW 60NW. OUTLOOK VALID 13/1200Z 37.1N 165.1W MAX WIND 50 KT...GUSTS 60 KT. 50 KT... 30NE 20SE 0SW 20NW. 34 KT... 60NE 50SE 30SW 50NW. REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 19.7N 141.5W NEXT ADVISORY AT 08/2100Z $$ FORECASTER HAGEN NNNN
NHC Webmaster

Tropical Storm Ivo Forecast Advisory Number 8

2 weeks 2 days ago
Issued at 1500 UTC FRI AUG 08 2025 000 WTPZ24 KNHC 081435 TCMEP4 TROPICAL STORM IVO FORECAST/ADVISORY NUMBER 8 NWS NATIONAL HURRICANE CENTER MIAMI FL EP092025 1500 UTC FRI AUG 08 2025 TROPICAL STORM CENTER LOCATED NEAR 20.7N 110.1W AT 08/1500Z POSITION ACCURATE WITHIN 30 NM PRESENT MOVEMENT TOWARD THE WEST-NORTHWEST OR 295 DEGREES AT 14 KT ESTIMATED MINIMUM CENTRAL PRESSURE 1001 MB MAX SUSTAINED WINDS 50 KT WITH GUSTS TO 60 KT. 50 KT....... 20NE 0SE 0SW 0NW. 34 KT....... 40NE 40SE 0SW 30NW. 4 M SEAS....120NE 120SE 30SW 60NW. 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 20.7N 110.1W AT 08/1500Z AT 08/1200Z CENTER WAS LOCATED NEAR 20.6N 109.6W FORECAST VALID 09/0000Z 21.1N 111.7W MAX WIND 55 KT...GUSTS 65 KT. 50 KT... 20NE 10SE 0SW 10NW. 34 KT... 40NE 40SE 20SW 30NW. FORECAST VALID 09/1200Z 21.3N 113.4W MAX WIND 60 KT...GUSTS 75 KT. 50 KT... 20NE 10SE 10SW 10NW. 34 KT... 30NE 40SE 20SW 30NW. FORECAST VALID 10/0000Z 21.3N 114.9W MAX WIND 55 KT...GUSTS 65 KT. 50 KT... 15NE 0SE 0SW 15NW. 34 KT... 30NE 30SE 20SW 30NW. FORECAST VALID 10/1200Z 21.5N 116.6W MAX WIND 45 KT...GUSTS 55 KT. 34 KT... 30NE 20SE 20SW 30NW. FORECAST VALID 11/0000Z 21.9N 118.3W...POST-TROPICAL MAX WIND 35 KT...GUSTS 45 KT. 34 KT... 30NE 0SE 0SW 30NW. FORECAST VALID 11/1200Z 22.0N 120.0W...POST-TROP/REMNT LOW MAX WIND 30 KT...GUSTS 40 KT. 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 12/1200Z 22.0N 124.5W...POST-TROP/REMNT LOW MAX WIND 25 KT...GUSTS 35 KT. OUTLOOK VALID 13/1200Z...DISSIPATED REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 20.7N 110.1W NEXT ADVISORY AT 08/2100Z $$ FORECASTER BERG
NHC Webmaster

Tropical Storm Ivo Wind Speed Probabilities Number 8

2 weeks 2 days ago
Issued at 1500 UTC FRI AUG 08 2025 000 FOPZ14 KNHC 081435 PWSEP4 TROPICAL STORM IVO WIND SPEED PROBABILITIES NUMBER 8 NWS NATIONAL HURRICANE CENTER MIAMI FL EP092025 1500 UTC FRI AUG 08 2025 AT 1500Z THE CENTER OF TROPICAL STORM IVO WAS LOCATED NEAR LATITUDE 20.7 NORTH...LONGITUDE 110.1 WEST WITH MAXIMUM SUSTAINED WINDS NEAR 50 KTS...60 MPH...95 KM/H. Z INDICATES COORDINATED UNIVERSAL TIME (GREENWICH) PACIFIC DAYLIGHT TIME (PDT)...SUBTRACT 7 HOURS FROM Z TIME HAWAIIAN STANDARD TIME (HST)...SUBTRACT 10 HOURS FROM Z TIME WIND SPEED PROBABILITY TABLE FOR SPECIFIC LOCATIONS CHANCES OF SUSTAINED (1-MINUTE AVERAGE) WIND SPEEDS OF AT LEAST ...34 KT (39 MPH... 63 KM/H)... ...50 KT (58 MPH... 93 KM/H)... ...64 KT (74 MPH...119 KM/H)... FOR LOCATIONS AND TIME PERIODS DURING THE NEXT 5 DAYS PROBABILITIES FOR LOCATIONS ARE GIVEN AS OP(CP) WHERE OP IS THE PROBABILITY OF THE EVENT BEGINNING DURING AN INDIVIDUAL TIME PERIOD (ONSET PROBABILITY) (CP) IS THE PROBABILITY OF THE EVENT OCCURRING BETWEEN 12Z FRI AND THE FORECAST HOUR (CUMULATIVE PROBABILITY) PROBABILITIES ARE GIVEN IN PERCENT X INDICATES PROBABILITIES LESS THAN 1 PERCENT PROBABILITIES FOR 34 KT AND 50 KT ARE SHOWN AT A GIVEN LOCATION WHEN THE 5-DAY CUMULATIVE PROBABILITY IS AT LEAST 3 PERCENT. PROBABILITIES FOR 34...50...64 KT SHOWN WHEN THE 5-DAY 64-KT CUMULATIVE PROBABILITY IS AT LEAST 1 PERCENT. - - - - WIND SPEED PROBABILITIES FOR SELECTED LOCATIONS - - - - FROM FROM FROM FROM FROM FROM FROM TIME 12Z FRI 00Z SAT 12Z SAT 00Z SUN 12Z SUN 12Z MON 12Z TUE PERIODS TO TO TO TO TO TO TO 00Z SAT 12Z SAT 00Z SUN 12Z SUN 12Z MON 12Z TUE 12Z WED FORECAST HOUR (12) (24) (36) (48) (72) (96) (120) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - LOCATION KT ISLA CLARION 34 X 1( 1) 2( 3) X( 3) X( 3) X( 3) X( 3) 20N 115W 34 X 2( 2) 13(15) 2(17) X(17) X(17) X(17) 25N 115W 34 X 1( 1) 1( 2) X( 2) 1( 3) X( 3) X( 3) 20N 120W 34 X X( X) 1( 1) 1( 2) 1( 3) X( 3) X( 3) $$ FORECASTER BERG
NHC Webmaster

Tropical Storm Ivo Public Advisory Number 8

2 weeks 2 days ago
Issued at 800 AM MST Fri Aug 08 2025 000 WTPZ34 KNHC 081435 TCPEP4 BULLETIN Tropical Storm Ivo Advisory Number 8 NWS National Hurricane Center Miami FL EP092025 800 AM MST Fri Aug 08 2025 ...IVO PASSING SOUTH OF THE BAJA CALIFORNIA PENINSULA... SUMMARY OF 800 AM MST...1500 UTC...INFORMATION ---------------------------------------------- LOCATION...20.7N 110.1W ABOUT 150 MI...245 KM S OF THE SOUTHERN TIP OF BAJA CALIFORNIA MAXIMUM SUSTAINED WINDS...60 MPH...95 KM/H PRESENT MOVEMENT...WNW OR 295 DEGREES AT 16 MPH...26 KM/H MINIMUM CENTRAL PRESSURE...1001 MB...29.56 INCHES WATCHES AND WARNINGS -------------------- Interests in the southern portion of the Baja California peninsula should continue to monitor the progress of Ivo. DISCUSSION AND OUTLOOK ---------------------- At 800 AM MST (1500 UTC), the center of Tropical Storm Ivo was located near latitude 20.7 North, longitude 110.1 West. Ivo is moving toward the west-northwest near 16 mph (26 km/h). A westward to west-northwestward motion at a slower speed is forecast during the next several days. Maximum sustained winds are near 60 mph (95 km/h) with higher gusts. Some strengthening is possible through tonight, but weakening is likely to begin on Saturday and continue into early next week. Ivo could become post-tropical by late Sunday. Tropical-storm-force winds extend outward up to 45 miles (75 km) from the center. The estimated minimum central pressure is 1001 mb (29.56 inches). HAZARDS AFFECTING LAND ---------------------- SURF: Swells generated by Ivo will continue to affect the southwestern coast of Mexico during the next day or so, and are beginning to reach the southern portion of the Baja California peninsula. These swells are likely to cause life-threatening surf and rip current conditions. Please consult products from your local weather office. A depiction of rip current risk for the United States can be found at: hurricanes.gov/graphics_ep4.shtml?ripCurrnets NEXT ADVISORY ------------- Next complete advisory at 200 PM MST. $$ Forecaster Berg
NHC Webmaster

Tropical Storm Henriette Forecast Advisory Number 17

2 weeks 2 days ago
Issued at 0900 UTC FRI AUG 08 2025 000 WTPZ23 KNHC 080841 TCMEP3 TROPICAL STORM HENRIETTE FORECAST/ADVISORY NUMBER 17 NWS NATIONAL HURRICANE CENTER MIAMI FL EP082025 0900 UTC FRI AUG 08 2025 TROPICAL STORM CENTER LOCATED NEAR 19.2N 140.1W AT 08/0900Z POSITION ACCURATE WITHIN 30 NM PRESENT MOVEMENT TOWARD THE WEST OR 280 DEGREES AT 15 KT ESTIMATED MINIMUM CENTRAL PRESSURE 1008 MB MAX SUSTAINED WINDS 35 KT WITH GUSTS TO 45 KT. 34 KT....... 50NE 0SE 0SW 50NW. 4 M SEAS.... 90NE 60SE 60SW 60NW. 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 19.2N 140.1W AT 08/0900Z AT 08/0600Z CENTER WAS LOCATED NEAR 19.1N 139.3W FORECAST VALID 08/1800Z 19.7N 142.3W MAX WIND 35 KT...GUSTS 45 KT. 34 KT... 40NE 0SE 0SW 40NW. FORECAST VALID 09/0600Z 20.7N 145.0W MAX WIND 35 KT...GUSTS 45 KT. 34 KT... 40NE 0SE 0SW 40NW. FORECAST VALID 09/1800Z 21.9N 147.5W MAX WIND 40 KT...GUSTS 50 KT. 34 KT... 50NE 0SE 0SW 40NW. FORECAST VALID 10/0600Z 23.3N 149.8W MAX WIND 45 KT...GUSTS 55 KT. 34 KT... 60NE 30SE 0SW 50NW. FORECAST VALID 10/1800Z 24.9N 152.0W MAX WIND 55 KT...GUSTS 65 KT. 50 KT... 20NE 0SE 0SW 20NW. 34 KT... 60NE 40SE 20SW 50NW. FORECAST VALID 11/0600Z 26.9N 154.5W MAX WIND 65 KT...GUSTS 80 KT. 64 KT... 15NE 0SE 0SW 0NW. 50 KT... 30NE 20SE 10SW 20NW. 34 KT... 70NE 40SE 30SW 60NW. 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 12/0600Z 31.1N 159.2W MAX WIND 70 KT...GUSTS 85 KT. 50 KT... 30NE 25SE 10SW 20NW. 34 KT... 70NE 50SE 40SW 60NW. OUTLOOK VALID 13/0600Z 35.8N 163.8W MAX WIND 55 KT...GUSTS 65 KT. 50 KT... 30NE 20SE 0SW 20NW. 34 KT... 60NE 50SE 20SW 50NW. REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 19.2N 140.1W THIS IS THE LAST FORECAST/ADVISORY ISSUED UNDER EAST PACIFIC BASIN HEADERS ON THIS SYSTEM. FUTURE INFORMATION ON HENRIETTE CAN BE FOUND IN FORECAST/ADVISORIES ISSUED UNDER CENTRAL PACIFIC BASIN HEADERS...AWIPS HEADER HFOTCMCP3...WMO HEADER WTPA23 PHFO...BEGINNING AT 1500 UTC. $$ FORECASTER JELSEMA (CPHC)
NHC Webmaster

SPC Aug 8, 2025 1300 UTC Day 1 Convective Outlook

2 weeks 2 days ago
SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0748 AM CDT Fri Aug 08 2025 Valid 081300Z - 091200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE EASTERN DAKOTAS AND UPPER MISSISSIPPI VALLEY... ...SUMMARY... Scattered severe thunderstorms are possible later today and tonight across parts of the northern Plains and Upper Midwest. Scattered damaging winds, large hail, and a couple tornadoes are possible. ...Northern Plains into the Upper Mississippi Valley... An extensive MCS which produced numerous severe wind gusts across ND earlier this morning has recently weakened across northern MN. While occasional strong to locally damaging gusts may still occur in the short term, this convection should continue weakening through the rest of the morning as it moves into a less favorable thermodynamic environment. In the wake of this activity, an upper trough/low will continue advancing eastward across the northern Rockies/Plains towards the Upper Midwest through the period. At the surface, a weak low over central SD this morning should develop northeastward to northern MN by this evening, while a trailing cold front advances southward across the northern/central High Plains. Outflow from the morning convection may act as a pseudo warm front and focus for renewed intense thunderstorm development later today across parts of central/northern MN. The southern extent and location of this boundary by this evening remains somewhat uncertain. Even so, a rather moist and strongly to extremely unstable airmass will be present east of the cold front and south of the outflow boundary by late this afternoon across the upper MS Valley. It still appears probable that additional surface-based convection may develop by late afternoon/early evening across eastern ND/northwest MN and vicinity as large-scale ascent preceding the upper trough/low overspreads the warm sector. While stronger flow aloft may tend to lag the surface cold front to some extent, there should still be sufficient deep-layer shear to support organized updrafts, including supercells with some large hail threat. Given a large degree of boundary-parallel flow aloft, a quick linear transition should occur this evening, with a greater threat for severe/damaging winds. A narrow window for a couple of tornadoes may exist across parts of MN, mainly this evening along/near the residual outflow boundary where effective SRH may become locally enhanced with a gradual strengthening of a southerly low-level jet. Otherwise, the threat for damaging winds may continue through tonight across parts of the upper MS Valley so long as any MCS that develops can remain surface based. Given the potential effects of the ongoing morning convection, confidence in a corridor of more concentrated wind potential remains too low to include greater severe probabilities with this update. ...High Plains... Thunderstorms are ongoing this morning along/north of a cold front in the western Dakotas. This activity may pose an isolated hail threat given ample MUCAPE and strong deep-layer shear. The potential for additional thunderstorms this afternoon/evening across the central High Plains either along or behind the front in a low-level upslope flow regime remains unclear. A conditional risk for supercells with associated large hail threat is still apparent, but overall coverage of intense convection may remain quite isolated. Farther south across the southern High Plains, high-based convection is expected to develop this afternoon within a hot and well-mixed boundary layer. Deep-layer flow and related shear will generally remain weak, but outflow-driven clusters may still be capable of localized severe gusts. ...Northern Lower Michigan... Similar to yesterday, isolated strong to severe thunderstorms may develop this afternoon and evening across parts of northern Lower MI and vicinity, along the northeast periphery of the substantial reservoir of instability over the central Plains and Midwest. Modest northwesterly flow aloft will provide sufficient shear for some updraft organization, with a threat for occasional hail and damaging winds. ..Gleason/Leitman.. 08/08/2025 Read more

SPC Aug 8, 2025 1300 UTC Day 1 Convective Outlook

2 weeks 2 days ago
SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0748 AM CDT Fri Aug 08 2025 Valid 081300Z - 091200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE EASTERN DAKOTAS AND UPPER MISSISSIPPI VALLEY... ...SUMMARY... Scattered severe thunderstorms are possible later today and tonight across parts of the northern Plains and Upper Midwest. Scattered damaging winds, large hail, and a couple tornadoes are possible. ...Northern Plains into the Upper Mississippi Valley... An extensive MCS which produced numerous severe wind gusts across ND earlier this morning has recently weakened across northern MN. While occasional strong to locally damaging gusts may still occur in the short term, this convection should continue weakening through the rest of the morning as it moves into a less favorable thermodynamic environment. In the wake of this activity, an upper trough/low will continue advancing eastward across the northern Rockies/Plains towards the Upper Midwest through the period. At the surface, a weak low over central SD this morning should develop northeastward to northern MN by this evening, while a trailing cold front advances southward across the northern/central High Plains. Outflow from the morning convection may act as a pseudo warm front and focus for renewed intense thunderstorm development later today across parts of central/northern MN. The southern extent and location of this boundary by this evening remains somewhat uncertain. Even so, a rather moist and strongly to extremely unstable airmass will be present east of the cold front and south of the outflow boundary by late this afternoon across the upper MS Valley. It still appears probable that additional surface-based convection may develop by late afternoon/early evening across eastern ND/northwest MN and vicinity as large-scale ascent preceding the upper trough/low overspreads the warm sector. While stronger flow aloft may tend to lag the surface cold front to some extent, there should still be sufficient deep-layer shear to support organized updrafts, including supercells with some large hail threat. Given a large degree of boundary-parallel flow aloft, a quick linear transition should occur this evening, with a greater threat for severe/damaging winds. A narrow window for a couple of tornadoes may exist across parts of MN, mainly this evening along/near the residual outflow boundary where effective SRH may become locally enhanced with a gradual strengthening of a southerly low-level jet. Otherwise, the threat for damaging winds may continue through tonight across parts of the upper MS Valley so long as any MCS that develops can remain surface based. Given the potential effects of the ongoing morning convection, confidence in a corridor of more concentrated wind potential remains too low to include greater severe probabilities with this update. ...High Plains... Thunderstorms are ongoing this morning along/north of a cold front in the western Dakotas. This activity may pose an isolated hail threat given ample MUCAPE and strong deep-layer shear. The potential for additional thunderstorms this afternoon/evening across the central High Plains either along or behind the front in a low-level upslope flow regime remains unclear. A conditional risk for supercells with associated large hail threat is still apparent, but overall coverage of intense convection may remain quite isolated. Farther south across the southern High Plains, high-based convection is expected to develop this afternoon within a hot and well-mixed boundary layer. Deep-layer flow and related shear will generally remain weak, but outflow-driven clusters may still be capable of localized severe gusts. ...Northern Lower Michigan... Similar to yesterday, isolated strong to severe thunderstorms may develop this afternoon and evening across parts of northern Lower MI and vicinity, along the northeast periphery of the substantial reservoir of instability over the central Plains and Midwest. Modest northwesterly flow aloft will provide sufficient shear for some updraft organization, with a threat for occasional hail and damaging winds. ..Gleason/Leitman.. 08/08/2025 Read more

SPC Aug 8, 2025 1300 UTC Day 1 Convective Outlook

2 weeks 2 days ago
SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0748 AM CDT Fri Aug 08 2025 Valid 081300Z - 091200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE EASTERN DAKOTAS AND UPPER MISSISSIPPI VALLEY... ...SUMMARY... Scattered severe thunderstorms are possible later today and tonight across parts of the northern Plains and Upper Midwest. Scattered damaging winds, large hail, and a couple tornadoes are possible. ...Northern Plains into the Upper Mississippi Valley... An extensive MCS which produced numerous severe wind gusts across ND earlier this morning has recently weakened across northern MN. While occasional strong to locally damaging gusts may still occur in the short term, this convection should continue weakening through the rest of the morning as it moves into a less favorable thermodynamic environment. In the wake of this activity, an upper trough/low will continue advancing eastward across the northern Rockies/Plains towards the Upper Midwest through the period. At the surface, a weak low over central SD this morning should develop northeastward to northern MN by this evening, while a trailing cold front advances southward across the northern/central High Plains. Outflow from the morning convection may act as a pseudo warm front and focus for renewed intense thunderstorm development later today across parts of central/northern MN. The southern extent and location of this boundary by this evening remains somewhat uncertain. Even so, a rather moist and strongly to extremely unstable airmass will be present east of the cold front and south of the outflow boundary by late this afternoon across the upper MS Valley. It still appears probable that additional surface-based convection may develop by late afternoon/early evening across eastern ND/northwest MN and vicinity as large-scale ascent preceding the upper trough/low overspreads the warm sector. While stronger flow aloft may tend to lag the surface cold front to some extent, there should still be sufficient deep-layer shear to support organized updrafts, including supercells with some large hail threat. Given a large degree of boundary-parallel flow aloft, a quick linear transition should occur this evening, with a greater threat for severe/damaging winds. A narrow window for a couple of tornadoes may exist across parts of MN, mainly this evening along/near the residual outflow boundary where effective SRH may become locally enhanced with a gradual strengthening of a southerly low-level jet. Otherwise, the threat for damaging winds may continue through tonight across parts of the upper MS Valley so long as any MCS that develops can remain surface based. Given the potential effects of the ongoing morning convection, confidence in a corridor of more concentrated wind potential remains too low to include greater severe probabilities with this update. ...High Plains... Thunderstorms are ongoing this morning along/north of a cold front in the western Dakotas. This activity may pose an isolated hail threat given ample MUCAPE and strong deep-layer shear. The potential for additional thunderstorms this afternoon/evening across the central High Plains either along or behind the front in a low-level upslope flow regime remains unclear. A conditional risk for supercells with associated large hail threat is still apparent, but overall coverage of intense convection may remain quite isolated. Farther south across the southern High Plains, high-based convection is expected to develop this afternoon within a hot and well-mixed boundary layer. Deep-layer flow and related shear will generally remain weak, but outflow-driven clusters may still be capable of localized severe gusts. ...Northern Lower Michigan... Similar to yesterday, isolated strong to severe thunderstorms may develop this afternoon and evening across parts of northern Lower MI and vicinity, along the northeast periphery of the substantial reservoir of instability over the central Plains and Midwest. Modest northwesterly flow aloft will provide sufficient shear for some updraft organization, with a threat for occasional hail and damaging winds. ..Gleason/Leitman.. 08/08/2025 Read more

SPC Aug 8, 2025 1300 UTC Day 1 Convective Outlook

2 weeks 2 days ago
SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0748 AM CDT Fri Aug 08 2025 Valid 081300Z - 091200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE EASTERN DAKOTAS AND UPPER MISSISSIPPI VALLEY... ...SUMMARY... Scattered severe thunderstorms are possible later today and tonight across parts of the northern Plains and Upper Midwest. Scattered damaging winds, large hail, and a couple tornadoes are possible. ...Northern Plains into the Upper Mississippi Valley... An extensive MCS which produced numerous severe wind gusts across ND earlier this morning has recently weakened across northern MN. While occasional strong to locally damaging gusts may still occur in the short term, this convection should continue weakening through the rest of the morning as it moves into a less favorable thermodynamic environment. In the wake of this activity, an upper trough/low will continue advancing eastward across the northern Rockies/Plains towards the Upper Midwest through the period. At the surface, a weak low over central SD this morning should develop northeastward to northern MN by this evening, while a trailing cold front advances southward across the northern/central High Plains. Outflow from the morning convection may act as a pseudo warm front and focus for renewed intense thunderstorm development later today across parts of central/northern MN. The southern extent and location of this boundary by this evening remains somewhat uncertain. Even so, a rather moist and strongly to extremely unstable airmass will be present east of the cold front and south of the outflow boundary by late this afternoon across the upper MS Valley. It still appears probable that additional surface-based convection may develop by late afternoon/early evening across eastern ND/northwest MN and vicinity as large-scale ascent preceding the upper trough/low overspreads the warm sector. While stronger flow aloft may tend to lag the surface cold front to some extent, there should still be sufficient deep-layer shear to support organized updrafts, including supercells with some large hail threat. Given a large degree of boundary-parallel flow aloft, a quick linear transition should occur this evening, with a greater threat for severe/damaging winds. A narrow window for a couple of tornadoes may exist across parts of MN, mainly this evening along/near the residual outflow boundary where effective SRH may become locally enhanced with a gradual strengthening of a southerly low-level jet. Otherwise, the threat for damaging winds may continue through tonight across parts of the upper MS Valley so long as any MCS that develops can remain surface based. Given the potential effects of the ongoing morning convection, confidence in a corridor of more concentrated wind potential remains too low to include greater severe probabilities with this update. ...High Plains... Thunderstorms are ongoing this morning along/north of a cold front in the western Dakotas. This activity may pose an isolated hail threat given ample MUCAPE and strong deep-layer shear. The potential for additional thunderstorms this afternoon/evening across the central High Plains either along or behind the front in a low-level upslope flow regime remains unclear. A conditional risk for supercells with associated large hail threat is still apparent, but overall coverage of intense convection may remain quite isolated. Farther south across the southern High Plains, high-based convection is expected to develop this afternoon within a hot and well-mixed boundary layer. Deep-layer flow and related shear will generally remain weak, but outflow-driven clusters may still be capable of localized severe gusts. ...Northern Lower Michigan... Similar to yesterday, isolated strong to severe thunderstorms may develop this afternoon and evening across parts of northern Lower MI and vicinity, along the northeast periphery of the substantial reservoir of instability over the central Plains and Midwest. Modest northwesterly flow aloft will provide sufficient shear for some updraft organization, with a threat for occasional hail and damaging winds. ..Gleason/Leitman.. 08/08/2025 Read more

SPC Aug 8, 2025 1300 UTC Day 1 Convective Outlook

2 weeks 2 days ago
SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0748 AM CDT Fri Aug 08 2025 Valid 081300Z - 091200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE EASTERN DAKOTAS AND UPPER MISSISSIPPI VALLEY... ...SUMMARY... Scattered severe thunderstorms are possible later today and tonight across parts of the northern Plains and Upper Midwest. Scattered damaging winds, large hail, and a couple tornadoes are possible. ...Northern Plains into the Upper Mississippi Valley... An extensive MCS which produced numerous severe wind gusts across ND earlier this morning has recently weakened across northern MN. While occasional strong to locally damaging gusts may still occur in the short term, this convection should continue weakening through the rest of the morning as it moves into a less favorable thermodynamic environment. In the wake of this activity, an upper trough/low will continue advancing eastward across the northern Rockies/Plains towards the Upper Midwest through the period. At the surface, a weak low over central SD this morning should develop northeastward to northern MN by this evening, while a trailing cold front advances southward across the northern/central High Plains. Outflow from the morning convection may act as a pseudo warm front and focus for renewed intense thunderstorm development later today across parts of central/northern MN. The southern extent and location of this boundary by this evening remains somewhat uncertain. Even so, a rather moist and strongly to extremely unstable airmass will be present east of the cold front and south of the outflow boundary by late this afternoon across the upper MS Valley. It still appears probable that additional surface-based convection may develop by late afternoon/early evening across eastern ND/northwest MN and vicinity as large-scale ascent preceding the upper trough/low overspreads the warm sector. While stronger flow aloft may tend to lag the surface cold front to some extent, there should still be sufficient deep-layer shear to support organized updrafts, including supercells with some large hail threat. Given a large degree of boundary-parallel flow aloft, a quick linear transition should occur this evening, with a greater threat for severe/damaging winds. A narrow window for a couple of tornadoes may exist across parts of MN, mainly this evening along/near the residual outflow boundary where effective SRH may become locally enhanced with a gradual strengthening of a southerly low-level jet. Otherwise, the threat for damaging winds may continue through tonight across parts of the upper MS Valley so long as any MCS that develops can remain surface based. Given the potential effects of the ongoing morning convection, confidence in a corridor of more concentrated wind potential remains too low to include greater severe probabilities with this update. ...High Plains... Thunderstorms are ongoing this morning along/north of a cold front in the western Dakotas. This activity may pose an isolated hail threat given ample MUCAPE and strong deep-layer shear. The potential for additional thunderstorms this afternoon/evening across the central High Plains either along or behind the front in a low-level upslope flow regime remains unclear. A conditional risk for supercells with associated large hail threat is still apparent, but overall coverage of intense convection may remain quite isolated. Farther south across the southern High Plains, high-based convection is expected to develop this afternoon within a hot and well-mixed boundary layer. Deep-layer flow and related shear will generally remain weak, but outflow-driven clusters may still be capable of localized severe gusts. ...Northern Lower Michigan... Similar to yesterday, isolated strong to severe thunderstorms may develop this afternoon and evening across parts of northern Lower MI and vicinity, along the northeast periphery of the substantial reservoir of instability over the central Plains and Midwest. Modest northwesterly flow aloft will provide sufficient shear for some updraft organization, with a threat for occasional hail and damaging winds. ..Gleason/Leitman.. 08/08/2025 Read more

Atlantic Tropical Weather Outlook

2 weeks 2 days ago
000
ABNT20 KNHC 081130
TWOAT

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
800 AM EDT Fri Aug 8 2025

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

Off the Southeastern United States:
A weak area of low pressure located a couple of hundred miles off
the coast of North Carolina is producing a few disorganized showers
and thunderstorms. Development of this system, if any, is expected
to be slow to occur over the next day or two while it moves
northeastward at 10 to 15 mph. The low is likely to merge with a
front over the weekend, ending its chances for tropical or
subtropical development.
* Formation chance through 48 hours...low...10 percent.
* Formation chance through 7 days...low...10 percent.

Central Atlantic (AL96):
A tropical wave over the central tropical Atlantic is producing
minimal shower activity. Development of this system appears
unlikely during the next day or two due to surrounding dry air, but
environmental conditions are forecast to become more conducive in a
few days. A tropical depression could form during the early
or middle part of next week while the system moves northwestward to
northward across the central tropical and subtropical Atlantic.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...medium...50 percent.

$$
Forecaster Berg
NHC Webmaster

Eastern North Pacific Tropical Weather Outlook

2 weeks 2 days ago
000
ABPZ20 KNHC 081129
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
500 AM PDT Fri Aug 8 2025

For the eastern and central North Pacific east of 180 longitude:

Active Systems:
The National Hurricane Center is issuing advisories on Tropical
Storm Henriette, located in the Central Pacific basin well east of
the Hawaiian Islands. The National Hurricane Center is also issuing
advisories on Tropical Storm Ivo, located over the Eastern Pacific
basin about 160 miles south of the southern tip of the Baja
California peninsula.

Tropical cyclone formation is not expected during the next 7 days.

$$
Forecaster Hagen
NHC Webmaster

SPC Severe Thunderstorm Watch 577 Status Reports

2 weeks 2 days ago
WW 0577 Status Updates
STATUS REPORT ON WW 577 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 35 WNW AXN TO 25 NNE DTL TO 30 ESE TVF TO 25 NNE TVF TO 20 NNE HCO. ..LEITMAN..08/08/25 ATTN...WFO...FGF...BIS... STATUS REPORT FOR WS 577 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS MNC005-007-029-057-077-111-135-159-081240- MN . MINNESOTA COUNTIES INCLUDED ARE BECKER BELTRAMI CLEARWATER HUBBARD LAKE OF THE WOODS OTTER TAIL ROSEAU WADENA THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more

SPC Severe Thunderstorm Watch 577

2 weeks 2 days ago
WW 577 SEVERE TSTM MN ND 080455Z - 081200Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 577 NWS Storm Prediction Center Norman OK 1155 PM CDT Thu Aug 7 2025 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Northwest Minnesota Eastern and Southern North Dakota * Effective this Thursday night and Friday morning from 1155 PM until 700 AM CDT. * Primary threats include... Scattered damaging winds likely with isolated significant gusts to 80 mph possible Isolated very large hail events to 2 inches in diameter possible A tornado or two possible SUMMARY...Multiple bowing linear clusters of storms will continue generally eastward overnight with potentially widespread wind damage, occasional hail, and perhaps some line-embedded tornado risk. The severe thunderstorm watch area is approximately along and 80 statute miles east and west of a line from 20 miles northeast of Hallock MN to 65 miles south of Jamestown ND. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU7). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Severe Thunderstorm Watch means conditions are favorable for severe thunderstorms in and close to the watch area. Persons in these areas should be on the lookout for threatening weather conditions and listen for later statements and possible warnings. Severe thunderstorms can and occasionally do produce tornadoes. && OTHER WATCH INFORMATION...CONTINUE...WW 576... AVIATION...A few severe thunderstorms with hail surface and aloft to 2 inches. Extreme turbulence and surface wind gusts to 70 knots. A few cumulonimbi with maximum tops to 550. Mean storm motion vector 26035. ...Guyer Read more

SPC Severe Thunderstorm Watch 577 Status Reports

2 weeks 2 days ago
WW 0577 Status Updates
STATUS REPORT ON WW 577 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 35 NNE ABR TO 25 WSW FAR TO 10 S GFK TO 50 WSW HCO TO 45 NW HCO. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 1903. ..LEITMAN..08/08/25 ATTN...WFO...FGF...BIS... STATUS REPORT FOR WS 577 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS MNC005-027-029-069-087-089-107-111-113-119-125-135-167-081040- MN . MINNESOTA COUNTIES INCLUDED ARE BECKER CLAY CLEARWATER KITTSON MAHNOMEN MARSHALL NORMAN OTTER TAIL PENNINGTON POLK RED LAKE ROSEAU WILKIN NDC017-035-067-073-077-081-097-099-081040- ND . NORTH DAKOTA COUNTIES INCLUDED ARE CASS GRAND FORKS PEMBINA RANSOM RICHLAND SARGENT TRAILL WALSH THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE Read more

SPC MD 1903

2 weeks 2 days ago
MD 1903 CONCERNING SEVERE THUNDERSTORM WATCH 577... FOR FAR EASTERN ND INTO NORTHWEST MN
Mesoscale Discussion 1903 NWS Storm Prediction Center Norman OK 0431 AM CDT Fri Aug 08 2025 Areas affected...far eastern ND into northwest MN Concerning...Severe Thunderstorm Watch 577... Valid 080931Z - 081100Z The severe weather threat for Severe Thunderstorm Watch 577 continues. SUMMARY...Strong to severe wind gusts remain possible the next couple hours across northwest Minnesota. A gradual weakening trend is expected through early morning with south and east extent across northeast/central Minnesota. DISCUSSION...A well organized bow echo moving out of eastern ND into northwest MN has produced gusts in the 55-80 kt range over the past 1-2 hours, and perhaps a brief tornado west of Grand Forks within leading-edge mesovortices. The VWP from KMVX shows a strong rear-inflow signature of 70-80 kt in the 1-2 km range. Severe gusts will likely persist another couple of hours into northwest MN given the well-organized nature of the bow echo and a favorable CAPE/shear downstream environment. With south and eastward extent, instability decreases and increasing inhibition should result in a gradual weakening trend into central and northeast MN through early morning. A local expansion of WW 577 may be needed across northwest MN/the remainder of the Grand Forks CWA. However, the need for a downstream watch is uncertain and will depend on convective trends over the next hour or so. ..Leitman.. 08/08/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...DLH...MPX...FGF...ABR...BIS... LAT...LON 49079676 49119547 49069466 48609406 47809364 47089367 46419419 45869528 45649644 45929804 46539786 48069793 48879796 49079676 MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 95 MPH MOST PROBABLE PEAK WIND GUST...65-80 MPH MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN Read more