SPC Day 1 Fire Weather Outlook

Severe Storms
2 weeks 3 days ago
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1113 AM CDT Wed Aug 06 2025 Valid 061700Z - 071200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE GREAT BASIN INTO THE CENTRAL ROCKIES... The previous forecast remains on track, with only slight adjustments made to the ongoing highlights to reflect the latest guidance consensus. ..Squitieri.. 08/06/2025 .PREV DISCUSSION... /ISSUED 0153 AM CDT Wed Aug 06 2025/ ...Synopsis... Broad midlevel troughing will persist across the northwestern CONUS, while an expansive mid/upper-level anticyclone remains centered on the Southwest/southern Rockies. ...Great Basin into the Central Rockies... Between the midlevel troughing and expansive mid/upper-level anticyclone, a belt of enhanced deep-layer west-southwesterly flow will remain in place across the Great Basin into the central Rockies. A diurnally deepening PBL will extent into this enhanced flow aloft, yielding an expansive overlap of around 20 mph sustained west-southwesterly surface winds and 10-15 percent RH. These conditions, combined with highly receptive fuels, will favor another day of critical fire-weather conditions across the region. ...Dry Thunderstorms - Southwest into the Central Rockies... Boundary-layer mixing beneath a plume of well-established midlevel moisture extending from the Southwest into the central Rockies will yield sufficient instability (characterized by inverted-V soundings) for isolated to widely scattered thunderstorm development -- generally focused along terrain features. PW values of 0.50 to 0.75 inches will promote mostly dry thunderstorms, which will pose a risk of lightning-induced ignitions and strong outflow winds. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook

Severe Storms
2 weeks 3 days ago
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1113 AM CDT Wed Aug 06 2025 Valid 061700Z - 071200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE GREAT BASIN INTO THE CENTRAL ROCKIES... The previous forecast remains on track, with only slight adjustments made to the ongoing highlights to reflect the latest guidance consensus. ..Squitieri.. 08/06/2025 .PREV DISCUSSION... /ISSUED 0153 AM CDT Wed Aug 06 2025/ ...Synopsis... Broad midlevel troughing will persist across the northwestern CONUS, while an expansive mid/upper-level anticyclone remains centered on the Southwest/southern Rockies. ...Great Basin into the Central Rockies... Between the midlevel troughing and expansive mid/upper-level anticyclone, a belt of enhanced deep-layer west-southwesterly flow will remain in place across the Great Basin into the central Rockies. A diurnally deepening PBL will extent into this enhanced flow aloft, yielding an expansive overlap of around 20 mph sustained west-southwesterly surface winds and 10-15 percent RH. These conditions, combined with highly receptive fuels, will favor another day of critical fire-weather conditions across the region. ...Dry Thunderstorms - Southwest into the Central Rockies... Boundary-layer mixing beneath a plume of well-established midlevel moisture extending from the Southwest into the central Rockies will yield sufficient instability (characterized by inverted-V soundings) for isolated to widely scattered thunderstorm development -- generally focused along terrain features. PW values of 0.50 to 0.75 inches will promote mostly dry thunderstorms, which will pose a risk of lightning-induced ignitions and strong outflow winds. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook

Severe Storms
2 weeks 3 days ago
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1113 AM CDT Wed Aug 06 2025 Valid 061700Z - 071200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE GREAT BASIN INTO THE CENTRAL ROCKIES... The previous forecast remains on track, with only slight adjustments made to the ongoing highlights to reflect the latest guidance consensus. ..Squitieri.. 08/06/2025 .PREV DISCUSSION... /ISSUED 0153 AM CDT Wed Aug 06 2025/ ...Synopsis... Broad midlevel troughing will persist across the northwestern CONUS, while an expansive mid/upper-level anticyclone remains centered on the Southwest/southern Rockies. ...Great Basin into the Central Rockies... Between the midlevel troughing and expansive mid/upper-level anticyclone, a belt of enhanced deep-layer west-southwesterly flow will remain in place across the Great Basin into the central Rockies. A diurnally deepening PBL will extent into this enhanced flow aloft, yielding an expansive overlap of around 20 mph sustained west-southwesterly surface winds and 10-15 percent RH. These conditions, combined with highly receptive fuels, will favor another day of critical fire-weather conditions across the region. ...Dry Thunderstorms - Southwest into the Central Rockies... Boundary-layer mixing beneath a plume of well-established midlevel moisture extending from the Southwest into the central Rockies will yield sufficient instability (characterized by inverted-V soundings) for isolated to widely scattered thunderstorm development -- generally focused along terrain features. PW values of 0.50 to 0.75 inches will promote mostly dry thunderstorms, which will pose a risk of lightning-induced ignitions and strong outflow winds. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook

Severe Storms
2 weeks 3 days ago
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1113 AM CDT Wed Aug 06 2025 Valid 061700Z - 071200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE GREAT BASIN INTO THE CENTRAL ROCKIES... The previous forecast remains on track, with only slight adjustments made to the ongoing highlights to reflect the latest guidance consensus. ..Squitieri.. 08/06/2025 .PREV DISCUSSION... /ISSUED 0153 AM CDT Wed Aug 06 2025/ ...Synopsis... Broad midlevel troughing will persist across the northwestern CONUS, while an expansive mid/upper-level anticyclone remains centered on the Southwest/southern Rockies. ...Great Basin into the Central Rockies... Between the midlevel troughing and expansive mid/upper-level anticyclone, a belt of enhanced deep-layer west-southwesterly flow will remain in place across the Great Basin into the central Rockies. A diurnally deepening PBL will extent into this enhanced flow aloft, yielding an expansive overlap of around 20 mph sustained west-southwesterly surface winds and 10-15 percent RH. These conditions, combined with highly receptive fuels, will favor another day of critical fire-weather conditions across the region. ...Dry Thunderstorms - Southwest into the Central Rockies... Boundary-layer mixing beneath a plume of well-established midlevel moisture extending from the Southwest into the central Rockies will yield sufficient instability (characterized by inverted-V soundings) for isolated to widely scattered thunderstorm development -- generally focused along terrain features. PW values of 0.50 to 0.75 inches will promote mostly dry thunderstorms, which will pose a risk of lightning-induced ignitions and strong outflow winds. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook

Severe Storms
2 weeks 3 days ago
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1113 AM CDT Wed Aug 06 2025 Valid 061700Z - 071200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE GREAT BASIN INTO THE CENTRAL ROCKIES... The previous forecast remains on track, with only slight adjustments made to the ongoing highlights to reflect the latest guidance consensus. ..Squitieri.. 08/06/2025 .PREV DISCUSSION... /ISSUED 0153 AM CDT Wed Aug 06 2025/ ...Synopsis... Broad midlevel troughing will persist across the northwestern CONUS, while an expansive mid/upper-level anticyclone remains centered on the Southwest/southern Rockies. ...Great Basin into the Central Rockies... Between the midlevel troughing and expansive mid/upper-level anticyclone, a belt of enhanced deep-layer west-southwesterly flow will remain in place across the Great Basin into the central Rockies. A diurnally deepening PBL will extent into this enhanced flow aloft, yielding an expansive overlap of around 20 mph sustained west-southwesterly surface winds and 10-15 percent RH. These conditions, combined with highly receptive fuels, will favor another day of critical fire-weather conditions across the region. ...Dry Thunderstorms - Southwest into the Central Rockies... Boundary-layer mixing beneath a plume of well-established midlevel moisture extending from the Southwest into the central Rockies will yield sufficient instability (characterized by inverted-V soundings) for isolated to widely scattered thunderstorm development -- generally focused along terrain features. PW values of 0.50 to 0.75 inches will promote mostly dry thunderstorms, which will pose a risk of lightning-induced ignitions and strong outflow winds. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook

Severe Storms
2 weeks 3 days ago
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1113 AM CDT Wed Aug 06 2025 Valid 061700Z - 071200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE GREAT BASIN INTO THE CENTRAL ROCKIES... The previous forecast remains on track, with only slight adjustments made to the ongoing highlights to reflect the latest guidance consensus. ..Squitieri.. 08/06/2025 .PREV DISCUSSION... /ISSUED 0153 AM CDT Wed Aug 06 2025/ ...Synopsis... Broad midlevel troughing will persist across the northwestern CONUS, while an expansive mid/upper-level anticyclone remains centered on the Southwest/southern Rockies. ...Great Basin into the Central Rockies... Between the midlevel troughing and expansive mid/upper-level anticyclone, a belt of enhanced deep-layer west-southwesterly flow will remain in place across the Great Basin into the central Rockies. A diurnally deepening PBL will extent into this enhanced flow aloft, yielding an expansive overlap of around 20 mph sustained west-southwesterly surface winds and 10-15 percent RH. These conditions, combined with highly receptive fuels, will favor another day of critical fire-weather conditions across the region. ...Dry Thunderstorms - Southwest into the Central Rockies... Boundary-layer mixing beneath a plume of well-established midlevel moisture extending from the Southwest into the central Rockies will yield sufficient instability (characterized by inverted-V soundings) for isolated to widely scattered thunderstorm development -- generally focused along terrain features. PW values of 0.50 to 0.75 inches will promote mostly dry thunderstorms, which will pose a risk of lightning-induced ignitions and strong outflow winds. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook

Severe Storms
2 weeks 3 days ago
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1113 AM CDT Wed Aug 06 2025 Valid 061700Z - 071200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE GREAT BASIN INTO THE CENTRAL ROCKIES... The previous forecast remains on track, with only slight adjustments made to the ongoing highlights to reflect the latest guidance consensus. ..Squitieri.. 08/06/2025 .PREV DISCUSSION... /ISSUED 0153 AM CDT Wed Aug 06 2025/ ...Synopsis... Broad midlevel troughing will persist across the northwestern CONUS, while an expansive mid/upper-level anticyclone remains centered on the Southwest/southern Rockies. ...Great Basin into the Central Rockies... Between the midlevel troughing and expansive mid/upper-level anticyclone, a belt of enhanced deep-layer west-southwesterly flow will remain in place across the Great Basin into the central Rockies. A diurnally deepening PBL will extent into this enhanced flow aloft, yielding an expansive overlap of around 20 mph sustained west-southwesterly surface winds and 10-15 percent RH. These conditions, combined with highly receptive fuels, will favor another day of critical fire-weather conditions across the region. ...Dry Thunderstorms - Southwest into the Central Rockies... Boundary-layer mixing beneath a plume of well-established midlevel moisture extending from the Southwest into the central Rockies will yield sufficient instability (characterized by inverted-V soundings) for isolated to widely scattered thunderstorm development -- generally focused along terrain features. PW values of 0.50 to 0.75 inches will promote mostly dry thunderstorms, which will pose a risk of lightning-induced ignitions and strong outflow winds. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook

Severe Storms
2 weeks 3 days ago
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1113 AM CDT Wed Aug 06 2025 Valid 061700Z - 071200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE GREAT BASIN INTO THE CENTRAL ROCKIES... The previous forecast remains on track, with only slight adjustments made to the ongoing highlights to reflect the latest guidance consensus. ..Squitieri.. 08/06/2025 .PREV DISCUSSION... /ISSUED 0153 AM CDT Wed Aug 06 2025/ ...Synopsis... Broad midlevel troughing will persist across the northwestern CONUS, while an expansive mid/upper-level anticyclone remains centered on the Southwest/southern Rockies. ...Great Basin into the Central Rockies... Between the midlevel troughing and expansive mid/upper-level anticyclone, a belt of enhanced deep-layer west-southwesterly flow will remain in place across the Great Basin into the central Rockies. A diurnally deepening PBL will extent into this enhanced flow aloft, yielding an expansive overlap of around 20 mph sustained west-southwesterly surface winds and 10-15 percent RH. These conditions, combined with highly receptive fuels, will favor another day of critical fire-weather conditions across the region. ...Dry Thunderstorms - Southwest into the Central Rockies... Boundary-layer mixing beneath a plume of well-established midlevel moisture extending from the Southwest into the central Rockies will yield sufficient instability (characterized by inverted-V soundings) for isolated to widely scattered thunderstorm development -- generally focused along terrain features. PW values of 0.50 to 0.75 inches will promote mostly dry thunderstorms, which will pose a risk of lightning-induced ignitions and strong outflow winds. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

Tropical Storm Henriette Wind Speed Probabilities Number 10

National Hurricane Center (NHC) Pacific Map
2 weeks 3 days ago
Issued at 1500 UTC WED AUG 06 2025 779 FOPZ13 KNHC 061456 PWSEP3 TROPICAL STORM HENRIETTE WIND SPEED PROBABILITIES NUMBER 10 NWS NATIONAL HURRICANE CENTER MIAMI FL EP082025 1500 UTC WED AUG 06 2025 AT 1500Z THE CENTER OF TROPICAL STORM HENRIETTE WAS LOCATED NEAR LATITUDE 18.1 NORTH...LONGITUDE 129.7 WEST WITH MAXIMUM SUSTAINED WINDS NEAR 45 KTS...50 MPH...85 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 WED 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 WED 00Z THU 12Z THU 00Z FRI 12Z FRI 12Z SAT 12Z SUN PERIODS TO TO TO TO TO TO TO 00Z THU 12Z THU 00Z FRI 12Z FRI 12Z SAT 12Z SUN 12Z MON FORECAST HOUR (12) (24) (36) (48) (72) (96) (120) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - LOCATION KT 20N 135W 34 1 11(12) 3(15) X(15) X(15) X(15) X(15) 20N 140W 34 X X( X) 4( 4) 30(34) 2(36) X(36) X(36) 20N 140W 50 X X( X) X( X) 6( 6) 1( 7) X( 7) X( 7) 20N 140W 64 X X( X) X( X) 1( 1) X( 1) X( 1) X( 1) 20N 145W 34 X X( X) X( X) 1( 1) 19(20) 1(21) X(21) 20N 145W 50 X X( X) X( X) X( X) 5( 5) X( 5) X( 5) 20N 150W 34 X X( X) X( X) X( X) 1( 1) 2( 3) X( 3) 25N 150W 34 X X( X) X( X) X( X) X( X) 19(19) 3(22) 25N 150W 50 X X( X) X( X) X( X) X( X) 3( 3) 2( 5) 25N 150W 64 X X( X) X( X) X( X) X( X) 1( 1) X( 1) 20N 151W 34 X X( X) X( X) X( X) 1( 1) 2( 3) X( 3) 26N 159W 34 X X( X) X( X) X( X) X( X) X( X) 3( 3) 30N 160W 34 X X( X) X( X) X( X) X( X) X( X) 3( 3) $$ FORECASTER D. ZELINSKY
NHC Webmaster

Tropical Storm Henriette Forecast Discussion Number 10

National Hurricane Center (NHC) Pacific Map
2 weeks 3 days ago
Issued at 500 AM HST Wed Aug 06 2025 546 WTPZ43 KNHC 061457 TCDEP3 Tropical Storm Henriette Discussion Number 10 NWS National Hurricane Center Miami FL EP082025 500 AM HST Wed Aug 06 2025 Henriette has changed very little this morning. It continues to produce a relatively small area of deep convection, with cold cloud tops present mostly to the north of its low-level center. The initial intensity remains 45 kt for this advisory, based on overnight ASCAT data and the lack of noticeable change in Henriette's structure since that time. Virtually no change was made to the NHC track forecast. Henriette is moving westward to west-northwestward to the south of a deep ridge centered over the northern east Pacific. In a few days, a trough approaching from the west will turn Henriette toward the northwest, taking the tropical cyclone north of Hawaii. The various deterministic and global ensemble models are all in good agreement on the forecast, so confidence in the track forecast is fairly high. The tropical storm is still forecast to slowly weaken during the next few days while it moves over cool SSTs near 24C. However, once Henriette moves north of Hawaii, it will move over warmer waters. Upper-level difluent flow associated with a mid-latitude trough to the northwest may also provide additional support for intensification. As a result, most of the dynamical models forecast strengthening to occur near the end of the forecast period, and the NHC intensity forecast has been adjusted upward accordingly. Some of the guidance is much higher, including both HAFS models, which show Henriette developing a robust inner core by 120 h. Additional adjustments to the intensity forecast at day 4 or 5 may be needed with future advisories. FORECAST POSITIONS AND MAX WINDS INIT 06/1500Z 18.1N 129.7W 45 KT 50 MPH 12H 07/0000Z 18.3N 132.0W 45 KT 50 MPH 24H 07/1200Z 18.6N 135.0W 40 KT 45 MPH 36H 08/0000Z 19.0N 138.0W 40 KT 45 MPH 48H 08/1200Z 19.6N 141.1W 40 KT 45 MPH 60H 09/0000Z 20.4N 144.0W 40 KT 45 MPH 72H 09/1200Z 21.5N 146.6W 40 KT 45 MPH 96H 10/1200Z 24.2N 151.3W 45 KT 50 MPH 120H 11/1200Z 27.5N 155.0W 60 KT 70 MPH $$ Forecaster D. Zelinsky
NHC Webmaster

Tropical Storm Henriette Public Advisory Number 10

National Hurricane Center (NHC) Pacific Map
2 weeks 3 days ago
Issued at 500 AM HST Wed Aug 06 2025 151 WTPZ33 KNHC 061456 TCPEP3 BULLETIN Tropical Storm Henriette Advisory Number 10 NWS National Hurricane Center Miami FL EP082025 500 AM HST Wed Aug 06 2025 ...HENRIETTE CONTINUES HEADING WEST-NORTHWESTWARD... SUMMARY OF 500 AM HST...1500 UTC...INFORMATION ---------------------------------------------- LOCATION...18.1N 129.7W ABOUT 1660 MI...2675 KM E OF HILO HAWAII MAXIMUM SUSTAINED WINDS...50 MPH...85 KM/H PRESENT MOVEMENT...W OR 280 DEGREES AT 15 MPH...24 KM/H MINIMUM CENTRAL PRESSURE...1004 MB...29.65 INCHES WATCHES AND WARNINGS -------------------- There are no coastal watches or warnings in effect. DISCUSSION AND OUTLOOK ---------------------- At 500 AM HST (1500 UTC), the center of Tropical Storm Henriette was located near latitude 18.1 North, longitude 129.7 West. Henriette is moving toward the west-northwest near 18 mph (30 km/h). The tropical storm is forecast to continue heading generally west-northwestward for the next several days at a slightly slower forward speed. Maximum sustained winds are near 50 mph (85 km/h) with higher gusts. Some slight weakening is possible today or tomorrow, but little overall change in strength is expected for the next couple of days. Tropical-storm-force winds extend outward up to 80 miles (130 km) from the center. The estimated minimum central pressure is 1004 mb (29.65 inches). HAZARDS AFFECTING LAND ---------------------- None. NEXT ADVISORY ------------- Next complete advisory at 1100 AM HST. $$ Forecaster D. Zelinsky
NHC Webmaster

Tropical Storm Henriette Forecast Advisory Number 10

National Hurricane Center (NHC) Pacific Map
2 weeks 3 days ago
Issued at 1500 UTC WED AUG 06 2025 000 WTPZ23 KNHC 061454 TCMEP3 TROPICAL STORM HENRIETTE FORECAST/ADVISORY NUMBER 10 NWS NATIONAL HURRICANE CENTER MIAMI FL EP082025 1500 UTC WED AUG 06 2025 TROPICAL STORM CENTER LOCATED NEAR 18.1N 129.7W AT 06/1500Z POSITION ACCURATE WITHIN 30 NM PRESENT MOVEMENT TOWARD THE WEST OR 280 DEGREES AT 13 KT ESTIMATED MINIMUM CENTRAL PRESSURE 1004 MB MAX SUSTAINED WINDS 45 KT WITH GUSTS TO 55 KT. 34 KT....... 70NE 50SE 40SW 70NW. 4 M SEAS....120NE 60SE 60SW 90NW. 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 18.1N 129.7W AT 06/1500Z AT 06/1200Z CENTER WAS LOCATED NEAR 18.0N 129.0W FORECAST VALID 07/0000Z 18.3N 132.0W MAX WIND 45 KT...GUSTS 55 KT. 34 KT... 70NE 50SE 40SW 70NW. FORECAST VALID 07/1200Z 18.6N 135.0W MAX WIND 40 KT...GUSTS 50 KT. 34 KT... 50NE 30SE 30SW 50NW. FORECAST VALID 08/0000Z 19.0N 138.0W MAX WIND 40 KT...GUSTS 50 KT. 34 KT... 50NE 30SE 0SW 50NW. FORECAST VALID 08/1200Z 19.6N 141.1W MAX WIND 40 KT...GUSTS 50 KT. 34 KT... 50NE 30SE 0SW 50NW. FORECAST VALID 09/0000Z 20.4N 144.0W MAX WIND 40 KT...GUSTS 50 KT. 34 KT... 50NE 30SE 0SW 50NW. FORECAST VALID 09/1200Z 21.5N 146.6W MAX WIND 40 KT...GUSTS 50 KT. 34 KT... 60NE 30SE 30SW 50NW. 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 10/1200Z 24.2N 151.3W MAX WIND 45 KT...GUSTS 55 KT. 34 KT... 60NE 40SE 30SW 50NW. OUTLOOK VALID 11/1200Z 27.5N 155.0W MAX WIND 60 KT...GUSTS 75 KT. 50 KT... 25NE 0SE 0SW 20NW. 34 KT... 60NE 50SE 40SW 50NW. REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 18.1N 129.7W NEXT ADVISORY AT 06/2100Z $$ FORECASTER D. ZELINSKY
NHC Webmaster

SPC Aug 6, 2025 1300 UTC Day 1 Convective Outlook

Severe Storms
2 weeks 3 days ago
SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0738 AM CDT Wed Aug 06 2025 Valid 061300Z - 071200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS TO THE MID-MISSISSIPPI VALLEY. AND PART OF NORTHERN MINNESOTA... ...SUMMARY... Isolated strong to severe thunderstorms are possible across parts of the northern/central Plains to the Mid-Mississippi Valley, and over part of northern Minnesota today and tonight. ...Northern/Central Plains into the Mid MS Valley... An MCS continues to push southward across the Mid MO Valley this morning. The current motion, particularly the westward backbuilding of storms into more of east-central NE, have oriented this system favorably to a moist low-level jet, which should support maintenance of this line for the next few hours. Echo tops within this system remain fairly cool and occasionally strong updrafts have persisted for the last several hours. Additionally, a notable rise/fall pressure couplet exists with this system, as sampled by the +4 mb pressure rise as SUX. These factors indicate the MCS remains mature and could still occasionally produce damaging gusts over the next few hours across southeast NE, southwest IA, northwest MO, and far northeast KS. This MCS should begin to weaken later this morning when the low-level jet weakens. The region will be within the mostly zonal flow between the upper ridging centered over NM and a shortwave trough moving through SK and MB. Some rising heights are possible during the second half of the period as the pattern amplifies ahead of a shortwave trough moving into the northern Rockies. A belt of stronger mid-level flow (i.e. around 40 kt at 500 mb) will extend across the region, and diurnal heating of the moist airmass in place will foster moderate to strong buoyancy. The resulting combination of buoyancy and shear would favor strong to severe thunderstorms, but the satellite imagery lacks any notable disturbances upstream and the large-scale ascent is nebulous. The surface pattern also lacks any well-defined features, with only weak troughing sampled from the central Dakotas to a weak low over northeast CO. As such, when and where convective initiation occurs, if it occurs at all, is uncertain. Convective initiation appears most likely near the Black Hills into western NE within southeasterly low-level upslope flow within a very moist/unstable airmass. Environmental conditions support supercells with a conditional risk for large hail and damaging winds. However, given the uncertainty regarding coverage, will maintain Marginal risk (level 1 of 5). ...Northern MN... A few storms may develop along the southern periphery of the Canadian Prairies shortwave upper trough and surface low. Lapse rates will be weaker across this area and the favorable thermodynamic environment will be narrow. Any stronger storms will likely remain close to the international border, but could produce locally strong gusts or marginal hail. ..Mosier/Bentley.. 08/06/2025 Read more

SPC Aug 6, 2025 1300 UTC Day 1 Convective Outlook

Severe Storms
2 weeks 3 days ago
SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0738 AM CDT Wed Aug 06 2025 Valid 061300Z - 071200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS TO THE MID-MISSISSIPPI VALLEY. AND PART OF NORTHERN MINNESOTA... ...SUMMARY... Isolated strong to severe thunderstorms are possible across parts of the northern/central Plains to the Mid-Mississippi Valley, and over part of northern Minnesota today and tonight. ...Northern/Central Plains into the Mid MS Valley... An MCS continues to push southward across the Mid MO Valley this morning. The current motion, particularly the westward backbuilding of storms into more of east-central NE, have oriented this system favorably to a moist low-level jet, which should support maintenance of this line for the next few hours. Echo tops within this system remain fairly cool and occasionally strong updrafts have persisted for the last several hours. Additionally, a notable rise/fall pressure couplet exists with this system, as sampled by the +4 mb pressure rise as SUX. These factors indicate the MCS remains mature and could still occasionally produce damaging gusts over the next few hours across southeast NE, southwest IA, northwest MO, and far northeast KS. This MCS should begin to weaken later this morning when the low-level jet weakens. The region will be within the mostly zonal flow between the upper ridging centered over NM and a shortwave trough moving through SK and MB. Some rising heights are possible during the second half of the period as the pattern amplifies ahead of a shortwave trough moving into the northern Rockies. A belt of stronger mid-level flow (i.e. around 40 kt at 500 mb) will extend across the region, and diurnal heating of the moist airmass in place will foster moderate to strong buoyancy. The resulting combination of buoyancy and shear would favor strong to severe thunderstorms, but the satellite imagery lacks any notable disturbances upstream and the large-scale ascent is nebulous. The surface pattern also lacks any well-defined features, with only weak troughing sampled from the central Dakotas to a weak low over northeast CO. As such, when and where convective initiation occurs, if it occurs at all, is uncertain. Convective initiation appears most likely near the Black Hills into western NE within southeasterly low-level upslope flow within a very moist/unstable airmass. Environmental conditions support supercells with a conditional risk for large hail and damaging winds. However, given the uncertainty regarding coverage, will maintain Marginal risk (level 1 of 5). ...Northern MN... A few storms may develop along the southern periphery of the Canadian Prairies shortwave upper trough and surface low. Lapse rates will be weaker across this area and the favorable thermodynamic environment will be narrow. Any stronger storms will likely remain close to the international border, but could produce locally strong gusts or marginal hail. ..Mosier/Bentley.. 08/06/2025 Read more

SPC Aug 6, 2025 1300 UTC Day 1 Convective Outlook

Severe Storms
2 weeks 3 days ago
SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0738 AM CDT Wed Aug 06 2025 Valid 061300Z - 071200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS TO THE MID-MISSISSIPPI VALLEY. AND PART OF NORTHERN MINNESOTA... ...SUMMARY... Isolated strong to severe thunderstorms are possible across parts of the northern/central Plains to the Mid-Mississippi Valley, and over part of northern Minnesota today and tonight. ...Northern/Central Plains into the Mid MS Valley... An MCS continues to push southward across the Mid MO Valley this morning. The current motion, particularly the westward backbuilding of storms into more of east-central NE, have oriented this system favorably to a moist low-level jet, which should support maintenance of this line for the next few hours. Echo tops within this system remain fairly cool and occasionally strong updrafts have persisted for the last several hours. Additionally, a notable rise/fall pressure couplet exists with this system, as sampled by the +4 mb pressure rise as SUX. These factors indicate the MCS remains mature and could still occasionally produce damaging gusts over the next few hours across southeast NE, southwest IA, northwest MO, and far northeast KS. This MCS should begin to weaken later this morning when the low-level jet weakens. The region will be within the mostly zonal flow between the upper ridging centered over NM and a shortwave trough moving through SK and MB. Some rising heights are possible during the second half of the period as the pattern amplifies ahead of a shortwave trough moving into the northern Rockies. A belt of stronger mid-level flow (i.e. around 40 kt at 500 mb) will extend across the region, and diurnal heating of the moist airmass in place will foster moderate to strong buoyancy. The resulting combination of buoyancy and shear would favor strong to severe thunderstorms, but the satellite imagery lacks any notable disturbances upstream and the large-scale ascent is nebulous. The surface pattern also lacks any well-defined features, with only weak troughing sampled from the central Dakotas to a weak low over northeast CO. As such, when and where convective initiation occurs, if it occurs at all, is uncertain. Convective initiation appears most likely near the Black Hills into western NE within southeasterly low-level upslope flow within a very moist/unstable airmass. Environmental conditions support supercells with a conditional risk for large hail and damaging winds. However, given the uncertainty regarding coverage, will maintain Marginal risk (level 1 of 5). ...Northern MN... A few storms may develop along the southern periphery of the Canadian Prairies shortwave upper trough and surface low. Lapse rates will be weaker across this area and the favorable thermodynamic environment will be narrow. Any stronger storms will likely remain close to the international border, but could produce locally strong gusts or marginal hail. ..Mosier/Bentley.. 08/06/2025 Read more