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Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0401 AM CDT Fri Aug 23 2024 Valid 261200Z - 311200Z ...DISCUSSION... Models continue to suggest potential for severe weather across parts of the Upper Mississippi Valley area Day4/Monday, as a mid-level short-wave trough is shunted northeastward across this region by the persistent central U.S. ridge. Timing of the advance of this feature differs between the GFS and ECMWF, casting some uncertainty, but enough agreement exists to maintain a 15% probability area across this region. One other area of interest Day 4/Monday is across portions of the southern New England/Mid-Atlantic vicinity within a northwesterly flow regime on the southwestern side of New England/Canadian Maritimes upper low. Enhanced northwesterlies aloft would be sufficient to produce rather fast-moving bands of storms, but degree of instability remains a substantial question at this time. With intensity of the convection thus still uncertain, will refrain at this time from introducing a risk area. As the north-central U.S. mid-level feature moves into/across Ontario Day 5, a decrease in severe risk is expected despite a weak frontal advance southeastward across the Great Lakes into the Ohio Valley. Beyond Day 5, models begin to deviate substantially, particularly with respect to their handling of the next trough expected to progress eastward across the Canadian Prairie and northwestern/north-central CONUS. While some severe potential could accompany this feature, particularly if an evolution that resembles the stronger ECMWF solution plays out, uncertainty precludes any reasonable assessment of severe potential. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0401 AM CDT Fri Aug 23 2024 Valid 261200Z - 311200Z ...DISCUSSION... Models continue to suggest potential for severe weather across parts of the Upper Mississippi Valley area Day4/Monday, as a mid-level short-wave trough is shunted northeastward across this region by the persistent central U.S. ridge. Timing of the advance of this feature differs between the GFS and ECMWF, casting some uncertainty, but enough agreement exists to maintain a 15% probability area across this region. One other area of interest Day 4/Monday is across portions of the southern New England/Mid-Atlantic vicinity within a northwesterly flow regime on the southwestern side of New England/Canadian Maritimes upper low. Enhanced northwesterlies aloft would be sufficient to produce rather fast-moving bands of storms, but degree of instability remains a substantial question at this time. With intensity of the convection thus still uncertain, will refrain at this time from introducing a risk area. As the north-central U.S. mid-level feature moves into/across Ontario Day 5, a decrease in severe risk is expected despite a weak frontal advance southeastward across the Great Lakes into the Ohio Valley. Beyond Day 5, models begin to deviate substantially, particularly with respect to their handling of the next trough expected to progress eastward across the Canadian Prairie and northwestern/north-central CONUS. While some severe potential could accompany this feature, particularly if an evolution that resembles the stronger ECMWF solution plays out, uncertainty precludes any reasonable assessment of severe potential. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0401 AM CDT Fri Aug 23 2024 Valid 261200Z - 311200Z ...DISCUSSION... Models continue to suggest potential for severe weather across parts of the Upper Mississippi Valley area Day4/Monday, as a mid-level short-wave trough is shunted northeastward across this region by the persistent central U.S. ridge. Timing of the advance of this feature differs between the GFS and ECMWF, casting some uncertainty, but enough agreement exists to maintain a 15% probability area across this region. One other area of interest Day 4/Monday is across portions of the southern New England/Mid-Atlantic vicinity within a northwesterly flow regime on the southwestern side of New England/Canadian Maritimes upper low. Enhanced northwesterlies aloft would be sufficient to produce rather fast-moving bands of storms, but degree of instability remains a substantial question at this time. With intensity of the convection thus still uncertain, will refrain at this time from introducing a risk area. As the north-central U.S. mid-level feature moves into/across Ontario Day 5, a decrease in severe risk is expected despite a weak frontal advance southeastward across the Great Lakes into the Ohio Valley. Beyond Day 5, models begin to deviate substantially, particularly with respect to their handling of the next trough expected to progress eastward across the Canadian Prairie and northwestern/north-central CONUS. While some severe potential could accompany this feature, particularly if an evolution that resembles the stronger ECMWF solution plays out, uncertainty precludes any reasonable assessment of severe potential. Read more

5-Day Uncertainty Track last updated Fri, 23 Aug 2024 08:39:41 GMT


Wind Speed Probabilities last updated Fri, 23 Aug 2024 09:29:11 GMT

Issued at 1100 PM HST Thu Aug 22 2024 000 WTPZ42 KNHC 230838 TCDEP2 Hurricane Gilma Discussion Number 20 NWS National Hurricane Center Miami FL EP072024 1100 PM HST Thu Aug 22 2024 The satellite presentation of Gilma has not changed much since the previous advisory. The ragged eye of the hurricane is still surrounded by deep convection, with the coldest cloud tops located over the western and southern portions of the inner core. Based on consensus T-5.5/102 kt Dvorak current intensity estimates from TAFB and SAB, and similar estimates from the various UW-CIMSS objective techniques, the initial intensity is held at 105 kt. The center of the hurricane has jogged westward during the past few hours, but the longer-term motion is still west-northwestward at about 5 kt. A deep-layer trough near the west coast of the United States is expected to lift out over the next couple of days, which will allow a high pressure ridge to build westward over the eastern North Pacific. As a result, Gilma should gradually move faster toward the west-northwest and west during the next several days. The track guidance remains tightly clustered, and the NHC forecast is essentially an update of the previous one with no notable changes. As previously discussed, the slow forward speed of Gilma is likely resulting in some upwelling of cooler waters underneath the hurricane. Although the vertical wind shear is forecast to remain relatively weak during the next couple of days, the track of Gilma will bring the hurricane over even cooler waters and into a drier mid-level environment by this weekend. These factors suggest at least gradual weakening should continue in the near term, followed by more significant weakening beyond 72 h as the cyclone encounters stronger shear and the upper air pattern becomes more convergent. Some slight downward adjustments were made to the NHC prediction later in the period. Gilma is forecast to become a post-tropical cyclone by 120 h, but the lack of organized convection in GFS and ECMWF model-simulated satellite imagery indicates this transition could occur as early as day 4. FORECAST POSITIONS AND MAX WINDS INIT 23/0900Z 17.4N 126.1W 105 KT 120 MPH 12H 23/1800Z 17.6N 127.2W 100 KT 115 MPH 24H 24/0600Z 18.0N 128.8W 95 KT 110 MPH 36H 24/1800Z 18.4N 130.5W 90 KT 105 MPH 48H 25/0600Z 18.7N 132.2W 80 KT 90 MPH 60H 25/1800Z 19.0N 134.1W 70 KT 80 MPH 72H 26/0600Z 19.3N 136.1W 65 KT 75 MPH 96H 27/0600Z 19.9N 140.8W 50 KT 60 MPH 120H 28/0600Z 20.5N 146.0W 35 KT 40 MPH...POST-TROPICAL $$ Forecaster Reinhart

Issued at 0900 UTC FRI AUG 23 2024 996 FOPZ12 KNHC 230834 PWSEP2 HURRICANE GILMA WIND SPEED PROBABILITIES NUMBER 20 NWS NATIONAL HURRICANE CENTER MIAMI FL EP072024 0900 UTC FRI AUG 23 2024 AT 0900Z THE CENTER OF HURRICANE GILMA WAS LOCATED NEAR LATITUDE 17.4 NORTH...LONGITUDE 126.1 WEST WITH MAXIMUM SUSTAINED WINDS NEAR 105 KTS...120 MPH...195 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 06Z 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 06Z FRI 18Z FRI 06Z SAT 18Z SAT 06Z SUN 06Z MON 06Z TUE PERIODS TO TO TO TO TO TO TO 18Z FRI 06Z SAT 18Z SAT 06Z SUN 06Z MON 06Z TUE 06Z WED FORECAST HOUR (12) (24) (36) (48) (72) (96) (120) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - LOCATION KT 15N 125W 34 2 1( 3) X( 3) X( 3) X( 3) X( 3) X( 3) 20N 125W 34 2 2( 4) 1( 5) X( 5) X( 5) X( 5) X( 5) 15N 130W 34 1 3( 4) 4( 8) 2(10) X(10) X(10) X(10) 20N 130W 34 2 19(21) 37(58) 5(63) 1(64) X(64) X(64) 20N 130W 50 X 1( 1) 11(12) 2(14) 1(15) X(15) X(15) 20N 130W 64 X X( X) 3( 3) 1( 4) X( 4) X( 4) X( 4) 15N 135W 34 X X( X) 1( 1) 2( 3) 4( 7) X( 7) X( 7) 20N 135W 34 X X( X) 3( 3) 13(16) 56(72) 1(73) X(73) 20N 135W 50 X X( X) X( X) 2( 2) 32(34) 1(35) X(35) 20N 135W 64 X X( X) X( X) X( X) 13(13) X(13) X(13) 25N 135W 34 X X( X) X( X) X( X) 2( 2) 1( 3) X( 3) 15N 140W 34 X X( X) X( X) X( X) 1( 1) 1( 2) 1( 3) 20N 140W 34 X X( X) X( X) X( X) 7( 7) 33(40) 3(43) 20N 140W 50 X X( X) X( X) X( X) 1( 1) 11(12) 1(13) 20N 140W 64 X X( X) X( X) X( X) X( X) 2( 2) X( 2) 20N 145W 34 X X( X) X( X) X( X) X( X) 3( 3) 13(16) $$ FORECASTER REINHART

Issued at 1100 PM HST Thu Aug 22 2024 000 WTPZ32 KNHC 230834 TCPEP2 BULLETIN Hurricane Gilma Advisory Number 20 NWS National Hurricane Center Miami FL EP072024 1100 PM HST Thu Aug 22 2024 ...GILMA REMAINS A MAJOR HURRICANE OVER OPEN WATERS... SUMMARY OF 1100 PM HST...0900 UTC...INFORMATION ----------------------------------------------- LOCATION...17.4N 126.1W ABOUT 1115 MI...1795 KM WSW OF THE SOUTHERN TIP OF BAJA CALIFORNIA ABOUT 1905 MI...3060 KM E OF HILO HAWAII MAXIMUM SUSTAINED WINDS...120 MPH...195 KM/H PRESENT MOVEMENT...WNW OR 290 DEGREES AT 6 MPH...9 KM/H MINIMUM CENTRAL PRESSURE...959 MB...28.32 INCHES WATCHES AND WARNINGS -------------------- There are no coastal watches or warnings in effect. DISCUSSION AND OUTLOOK ---------------------- At 1100 PM HST (0900 UTC), the center of Hurricane Gilma was located near latitude 17.4 North, longitude 126.1 West. Gilma is moving toward the west-northwest near 6 mph (9 km/h). Gradual acceleration toward the west-northwest and west is expected during the next several days. Maximum sustained winds are near 120 mph (195 km/h) with higher gusts. Gilma is a category 3 hurricane on the Saffir-Simpson Hurricane Wind Scale. Weakening is forecast during the next several days, but Gilma is expected to remain a hurricane through much of the upcoming weekend. Hurricane-force winds extend outward up to 35 miles (55 km) from the center and tropical-storm-force winds extend outward up to 115 miles (185 km). The estimated minimum central pressure is 959 mb (28.32 inches). HAZARDS AFFECTING LAND ---------------------- None NEXT ADVISORY ------------- Next complete advisory at 500 AM HST. $$ Forecaster Reinhart

...GILMA REMAINS A MAJOR HURRICANE OVER OPEN WATERS... As of 11:00 PM HST Thu Aug 22 the center of Gilma was located near 17.4, -126.1 with movement WNW at 6 mph. The minimum central pressure was 959 mb with maximum sustained winds of about 120 mph.

Issued at 0900 UTC FRI AUG 23 2024 000 WTPZ22 KNHC 230833 TCMEP2 HURRICANE GILMA FORECAST/ADVISORY NUMBER 20 NWS NATIONAL HURRICANE CENTER MIAMI FL EP072024 0900 UTC FRI AUG 23 2024 HURRICANE CENTER LOCATED NEAR 17.4N 126.1W AT 23/0900Z POSITION ACCURATE WITHIN 20 NM PRESENT MOVEMENT TOWARD THE WEST-NORTHWEST OR 290 DEGREES AT 5 KT ESTIMATED MINIMUM CENTRAL PRESSURE 959 MB EYE DIAMETER 10 NM MAX SUSTAINED WINDS 105 KT WITH GUSTS TO 130 KT. 64 KT....... 30NE 25SE 25SW 30NW. 50 KT....... 50NE 40SE 40SW 50NW. 34 KT.......100NE 90SE 80SW 100NW. 12 FT SEAS..180NE 150SE 180SW 180NW. 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 17.4N 126.1W AT 23/0900Z AT 23/0600Z CENTER WAS LOCATED NEAR 17.3N 125.8W FORECAST VALID 23/1800Z 17.6N 127.2W MAX WIND 100 KT...GUSTS 120 KT. 64 KT... 30NE 20SE 20SW 25NW. 50 KT... 50NE 40SE 40SW 50NW. 34 KT...100NE 80SE 80SW 100NW. FORECAST VALID 24/0600Z 18.0N 128.8W MAX WIND 95 KT...GUSTS 115 KT. 64 KT... 25NE 20SE 20SW 25NW. 50 KT... 40NE 30SE 30SW 40NW. 34 KT... 90NE 70SE 70SW 90NW. FORECAST VALID 24/1800Z 18.4N 130.5W MAX WIND 90 KT...GUSTS 110 KT. 64 KT... 25NE 20SE 20SW 25NW. 50 KT... 40NE 30SE 30SW 40NW. 34 KT... 90NE 60SE 60SW 90NW. FORECAST VALID 25/0600Z 18.7N 132.2W MAX WIND 80 KT...GUSTS 100 KT. 64 KT... 25NE 15SE 15SW 20NW. 50 KT... 40NE 30SE 30SW 40NW. 34 KT... 90NE 60SE 60SW 90NW. FORECAST VALID 25/1800Z 19.0N 134.1W MAX WIND 70 KT...GUSTS 85 KT. 50 KT... 40NE 30SE 30SW 40NW. 34 KT... 90NE 60SE 60SW 80NW. FORECAST VALID 26/0600Z 19.3N 136.1W MAX WIND 65 KT...GUSTS 80 KT. 50 KT... 30NE 20SE 20SW 30NW. 34 KT... 90NE 50SE 50SW 80NW. 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 27/0600Z 19.9N 140.8W MAX WIND 50 KT...GUSTS 60 KT. 50 KT... 20NE 0SE 0SW 20NW. 34 KT... 70NE 30SE 30SW 70NW. OUTLOOK VALID 28/0600Z 20.5N 146.0W...POST-TROPICAL MAX WIND 35 KT...GUSTS 45 KT. 34 KT... 40NE 0SE 0SW 40NW. REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 17.4N 126.1W NEXT ADVISORY AT 23/1500Z $$ FORECASTER REINHART

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0245 AM CDT Fri Aug 23 2024 Valid 251200Z - 261200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE EASTERN DAKOTAS AND INTO NORTHERN MINNESOTA... ...SUMMARY... Severe weather risk is expected across the northern Plains area, and in a more isolated manner southwestward into the southern Rockies on Sunday. ...Synopsis... A persistent central U.S. upper ridge will be suppressed southward with time on Sunday, as a western U.S. trough shifts northeastward across the Intermountain West toward -- and eventually into -- the northern Plains/central High Plains area. At the surface, a cold front will accompany the upper system, shifting eastward into the northern/central Plains area, and southeastward across the southern Rockies. This front will focus convective development through the period. ...Northern Plains area southwestward into the southern Rockies... Daytime heating of a moist pre-frontal boundary layer will result in strong destabilization within an axis focused across the eastern Dakotas. While a low-level capping inversion should inhibit widespread convective development, isolated storms are forecast to initiate during the afternoon. As the upper trough advances, a lead belt of moderate -- 30 to 40 kt -- southwesterly flow is forecast atop the frontal zone. Resulting shear will support organized/rotating updrafts, and as such, attendant risks for large hail and damaging wind gusts. Farther southwestward along the front, a much less unstable airmass is anticipated -- into the central High Plains and southern Rockies. However, a deep mixed layer promoting potential for evaporatively driven downdraft acceleration, and the aforementioned/enhanced belt of southwesterlies at mid levels, suggest potential for damaging wind gusts with a few of the stronger storms/bands of storms which evolve during the afternoon and evening. ..Goss.. 08/23/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0245 AM CDT Fri Aug 23 2024 Valid 251200Z - 261200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE EASTERN DAKOTAS AND INTO NORTHERN MINNESOTA... ...SUMMARY... Severe weather risk is expected across the northern Plains area, and in a more isolated manner southwestward into the southern Rockies on Sunday. ...Synopsis... A persistent central U.S. upper ridge will be suppressed southward with time on Sunday, as a western U.S. trough shifts northeastward across the Intermountain West toward -- and eventually into -- the northern Plains/central High Plains area. At the surface, a cold front will accompany the upper system, shifting eastward into the northern/central Plains area, and southeastward across the southern Rockies. This front will focus convective development through the period. ...Northern Plains area southwestward into the southern Rockies... Daytime heating of a moist pre-frontal boundary layer will result in strong destabilization within an axis focused across the eastern Dakotas. While a low-level capping inversion should inhibit widespread convective development, isolated storms are forecast to initiate during the afternoon. As the upper trough advances, a lead belt of moderate -- 30 to 40 kt -- southwesterly flow is forecast atop the frontal zone. Resulting shear will support organized/rotating updrafts, and as such, attendant risks for large hail and damaging wind gusts. Farther southwestward along the front, a much less unstable airmass is anticipated -- into the central High Plains and southern Rockies. However, a deep mixed layer promoting potential for evaporatively driven downdraft acceleration, and the aforementioned/enhanced belt of southwesterlies at mid levels, suggest potential for damaging wind gusts with a few of the stronger storms/bands of storms which evolve during the afternoon and evening. ..Goss.. 08/23/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0245 AM CDT Fri Aug 23 2024 Valid 251200Z - 261200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE EASTERN DAKOTAS AND INTO NORTHERN MINNESOTA... ...SUMMARY... Severe weather risk is expected across the northern Plains area, and in a more isolated manner southwestward into the southern Rockies on Sunday. ...Synopsis... A persistent central U.S. upper ridge will be suppressed southward with time on Sunday, as a western U.S. trough shifts northeastward across the Intermountain West toward -- and eventually into -- the northern Plains/central High Plains area. At the surface, a cold front will accompany the upper system, shifting eastward into the northern/central Plains area, and southeastward across the southern Rockies. This front will focus convective development through the period. ...Northern Plains area southwestward into the southern Rockies... Daytime heating of a moist pre-frontal boundary layer will result in strong destabilization within an axis focused across the eastern Dakotas. While a low-level capping inversion should inhibit widespread convective development, isolated storms are forecast to initiate during the afternoon. As the upper trough advances, a lead belt of moderate -- 30 to 40 kt -- southwesterly flow is forecast atop the frontal zone. Resulting shear will support organized/rotating updrafts, and as such, attendant risks for large hail and damaging wind gusts. Farther southwestward along the front, a much less unstable airmass is anticipated -- into the central High Plains and southern Rockies. However, a deep mixed layer promoting potential for evaporatively driven downdraft acceleration, and the aforementioned/enhanced belt of southwesterlies at mid levels, suggest potential for damaging wind gusts with a few of the stronger storms/bands of storms which evolve during the afternoon and evening. ..Goss.. 08/23/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0245 AM CDT Fri Aug 23 2024 Valid 251200Z - 261200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE EASTERN DAKOTAS AND INTO NORTHERN MINNESOTA... ...SUMMARY... Severe weather risk is expected across the northern Plains area, and in a more isolated manner southwestward into the southern Rockies on Sunday. ...Synopsis... A persistent central U.S. upper ridge will be suppressed southward with time on Sunday, as a western U.S. trough shifts northeastward across the Intermountain West toward -- and eventually into -- the northern Plains/central High Plains area. At the surface, a cold front will accompany the upper system, shifting eastward into the northern/central Plains area, and southeastward across the southern Rockies. This front will focus convective development through the period. ...Northern Plains area southwestward into the southern Rockies... Daytime heating of a moist pre-frontal boundary layer will result in strong destabilization within an axis focused across the eastern Dakotas. While a low-level capping inversion should inhibit widespread convective development, isolated storms are forecast to initiate during the afternoon. As the upper trough advances, a lead belt of moderate -- 30 to 40 kt -- southwesterly flow is forecast atop the frontal zone. Resulting shear will support organized/rotating updrafts, and as such, attendant risks for large hail and damaging wind gusts. Farther southwestward along the front, a much less unstable airmass is anticipated -- into the central High Plains and southern Rockies. However, a deep mixed layer promoting potential for evaporatively driven downdraft acceleration, and the aforementioned/enhanced belt of southwesterlies at mid levels, suggest potential for damaging wind gusts with a few of the stronger storms/bands of storms which evolve during the afternoon and evening. ..Goss.. 08/23/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0245 AM CDT Fri Aug 23 2024 Valid 251200Z - 261200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE EASTERN DAKOTAS AND INTO NORTHERN MINNESOTA... ...SUMMARY... Severe weather risk is expected across the northern Plains area, and in a more isolated manner southwestward into the southern Rockies on Sunday. ...Synopsis... A persistent central U.S. upper ridge will be suppressed southward with time on Sunday, as a western U.S. trough shifts northeastward across the Intermountain West toward -- and eventually into -- the northern Plains/central High Plains area. At the surface, a cold front will accompany the upper system, shifting eastward into the northern/central Plains area, and southeastward across the southern Rockies. This front will focus convective development through the period. ...Northern Plains area southwestward into the southern Rockies... Daytime heating of a moist pre-frontal boundary layer will result in strong destabilization within an axis focused across the eastern Dakotas. While a low-level capping inversion should inhibit widespread convective development, isolated storms are forecast to initiate during the afternoon. As the upper trough advances, a lead belt of moderate -- 30 to 40 kt -- southwesterly flow is forecast atop the frontal zone. Resulting shear will support organized/rotating updrafts, and as such, attendant risks for large hail and damaging wind gusts. Farther southwestward along the front, a much less unstable airmass is anticipated -- into the central High Plains and southern Rockies. However, a deep mixed layer promoting potential for evaporatively driven downdraft acceleration, and the aforementioned/enhanced belt of southwesterlies at mid levels, suggest potential for damaging wind gusts with a few of the stronger storms/bands of storms which evolve during the afternoon and evening. ..Goss.. 08/23/2024 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0148 AM CDT Fri Aug 23 2024 Valid 241200Z - 251200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF NORTHERN/CENTRAL WYOMING... ...Synopsis... A mid-level trough over the Pacific Northwest will shift east and allow a belt of enhanced mid-level flow to overspread parts of the eastern Great Basin and the Northern Rockies. Afternoon heating/mixing will allow for sustained winds of 20-25 mph across the region while RH values fall into the upper teens and low 20s F. Fuels across portions far eastern Great Basin appear marginally receptive, and Elevated highlights have been maintained for this region, whereas fuels across parts of Wyoming appear more receptive where a Critical delineation has been added. In addition, potential for isolated dry thunderstorms has been introduced for the northern Great Basin in association with forcing from the advancing trough. Fuels in this region remain receptive to large-fire spread amid PWAT values that are projected to remain below 0.75 inches. ..Karstens.. 08/23/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0148 AM CDT Fri Aug 23 2024 Valid 241200Z - 251200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF NORTHERN/CENTRAL WYOMING... ...Synopsis... A mid-level trough over the Pacific Northwest will shift east and allow a belt of enhanced mid-level flow to overspread parts of the eastern Great Basin and the Northern Rockies. Afternoon heating/mixing will allow for sustained winds of 20-25 mph across the region while RH values fall into the upper teens and low 20s F. Fuels across portions far eastern Great Basin appear marginally receptive, and Elevated highlights have been maintained for this region, whereas fuels across parts of Wyoming appear more receptive where a Critical delineation has been added. In addition, potential for isolated dry thunderstorms has been introduced for the northern Great Basin in association with forcing from the advancing trough. Fuels in this region remain receptive to large-fire spread amid PWAT values that are projected to remain below 0.75 inches. ..Karstens.. 08/23/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0148 AM CDT Fri Aug 23 2024 Valid 241200Z - 251200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF NORTHERN/CENTRAL WYOMING... ...Synopsis... A mid-level trough over the Pacific Northwest will shift east and allow a belt of enhanced mid-level flow to overspread parts of the eastern Great Basin and the Northern Rockies. Afternoon heating/mixing will allow for sustained winds of 20-25 mph across the region while RH values fall into the upper teens and low 20s F. Fuels across portions far eastern Great Basin appear marginally receptive, and Elevated highlights have been maintained for this region, whereas fuels across parts of Wyoming appear more receptive where a Critical delineation has been added. In addition, potential for isolated dry thunderstorms has been introduced for the northern Great Basin in association with forcing from the advancing trough. Fuels in this region remain receptive to large-fire spread amid PWAT values that are projected to remain below 0.75 inches. ..Karstens.. 08/23/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0148 AM CDT Fri Aug 23 2024 Valid 241200Z - 251200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF NORTHERN/CENTRAL WYOMING... ...Synopsis... A mid-level trough over the Pacific Northwest will shift east and allow a belt of enhanced mid-level flow to overspread parts of the eastern Great Basin and the Northern Rockies. Afternoon heating/mixing will allow for sustained winds of 20-25 mph across the region while RH values fall into the upper teens and low 20s F. Fuels across portions far eastern Great Basin appear marginally receptive, and Elevated highlights have been maintained for this region, whereas fuels across parts of Wyoming appear more receptive where a Critical delineation has been added. In addition, potential for isolated dry thunderstorms has been introduced for the northern Great Basin in association with forcing from the advancing trough. Fuels in this region remain receptive to large-fire spread amid PWAT values that are projected to remain below 0.75 inches. ..Karstens.. 08/23/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0148 AM CDT Fri Aug 23 2024 Valid 241200Z - 251200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF NORTHERN/CENTRAL WYOMING... ...Synopsis... A mid-level trough over the Pacific Northwest will shift east and allow a belt of enhanced mid-level flow to overspread parts of the eastern Great Basin and the Northern Rockies. Afternoon heating/mixing will allow for sustained winds of 20-25 mph across the region while RH values fall into the upper teens and low 20s F. Fuels across portions far eastern Great Basin appear marginally receptive, and Elevated highlights have been maintained for this region, whereas fuels across parts of Wyoming appear more receptive where a Critical delineation has been added. In addition, potential for isolated dry thunderstorms has been introduced for the northern Great Basin in association with forcing from the advancing trough. Fuels in this region remain receptive to large-fire spread amid PWAT values that are projected to remain below 0.75 inches. ..Karstens.. 08/23/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0144 AM CDT Fri Aug 23 2024 Valid 231200Z - 241200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE GREAT BASIN... ...Synopsis... A mid-level trough will enter portions of the Pacific Northwest, with enhanced mid-level flow overspreading portions of the Great Basin and vicinity. Afternoon heating/mixing will result in sustained surface winds of 20-25 mph while RH values drop into the teens, resulting in Elevated to Critical fire-weather conditions for this region. In addition, forcing for ascent associated with the aforementioned trough will allow for thunderstorms to develop across the Pacific Northwest, with a mix of wet and dry storms expected. Given dry/receptive fuels across the region, the area delineating isolated dry thunderstorm potential has been maintained. ..Karstens.. 08/23/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more