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SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0110 AM CDT Sat Aug 24 2024 Valid 251200Z - 261200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE EASTERN DAKOTAS INTO NORTHWESTERN MINNESOTA... ...SUMMARY... Scattered severe storms may develop across the northern Plains area on Sunday, with more isolated severe potential southwestward into the southern Rockies on Sunday. A couple of strong/marginally severe storms may also occur across the Lower Great Lakes/Upper Ohio Valley vicinity. ...Synopsis... A progressing western U.S. upper trough is forecast to gradually weaken, as it impinges on a persistent central U.S. ridge. The result will be that the trough gets shunted northeastward toward Montana/Wyoming with time. Meanwhile, weak upper troughing will persist over the Northeast. At the surface, a cold front will progress eastward across the Canadian Prairie, and the north-central U.S. with time. By the end of the period, the front should stretch from Minnesota southwestward to northeastern Colorado. ...Northern Plains southwestward to the Four Corners region... As the western U.S. trough advances eastward, large-scale ascent will support scattered thunderstorm development across the Intermountain Region, within a diurnally destabilizing airmass. While CAPE will remain limited, moderate southwesterly flow aloft ahead of the trough will allow some storm organization/longevity at time. This, combined with a deep mixed layer providing support for enhanced downdrafts with the stronger cells, will result in risk for locally severe wind gusts. More substantial severe risk could evolve across portions of the north-central states, where much greater instability will evolve. Though the airmass should remain capped in most areas, ascent may be sufficient to support local cap breaches by late afternoon to allow isolated storm development. If storms develop, upscale growth near convective outflows would be expected, possibly resulting in evening/overnight MCS development. Large hail would be possible with the initial storms, though with locally damaging gusts likely to be the dominant risk. Still, given the capping that is anticipated, and questions whether ascent will be sufficient to allow storm development, will maintain only conditional 15%/SLGT risk at this time. ...Lower Great Lakes/Upper Ohio Valley area... On the western fringe of the northeastern U.S. trough, moderate northwesterly flow aloft may combine with modest afternoon destabilization to support isolated storm development. Assuming this occurs, a few strong gusts would be possible as storms would move rather quickly southeastward. The main question remains the degree of destabilization which may occur, and thus will introduce only 5%/MRGL risk at this time. ..Goss.. 08/24/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0110 AM CDT Sat Aug 24 2024 Valid 251200Z - 261200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE EASTERN DAKOTAS INTO NORTHWESTERN MINNESOTA... ...SUMMARY... Scattered severe storms may develop across the northern Plains area on Sunday, with more isolated severe potential southwestward into the southern Rockies on Sunday. A couple of strong/marginally severe storms may also occur across the Lower Great Lakes/Upper Ohio Valley vicinity. ...Synopsis... A progressing western U.S. upper trough is forecast to gradually weaken, as it impinges on a persistent central U.S. ridge. The result will be that the trough gets shunted northeastward toward Montana/Wyoming with time. Meanwhile, weak upper troughing will persist over the Northeast. At the surface, a cold front will progress eastward across the Canadian Prairie, and the north-central U.S. with time. By the end of the period, the front should stretch from Minnesota southwestward to northeastern Colorado. ...Northern Plains southwestward to the Four Corners region... As the western U.S. trough advances eastward, large-scale ascent will support scattered thunderstorm development across the Intermountain Region, within a diurnally destabilizing airmass. While CAPE will remain limited, moderate southwesterly flow aloft ahead of the trough will allow some storm organization/longevity at time. This, combined with a deep mixed layer providing support for enhanced downdrafts with the stronger cells, will result in risk for locally severe wind gusts. More substantial severe risk could evolve across portions of the north-central states, where much greater instability will evolve. Though the airmass should remain capped in most areas, ascent may be sufficient to support local cap breaches by late afternoon to allow isolated storm development. If storms develop, upscale growth near convective outflows would be expected, possibly resulting in evening/overnight MCS development. Large hail would be possible with the initial storms, though with locally damaging gusts likely to be the dominant risk. Still, given the capping that is anticipated, and questions whether ascent will be sufficient to allow storm development, will maintain only conditional 15%/SLGT risk at this time. ...Lower Great Lakes/Upper Ohio Valley area... On the western fringe of the northeastern U.S. trough, moderate northwesterly flow aloft may combine with modest afternoon destabilization to support isolated storm development. Assuming this occurs, a few strong gusts would be possible as storms would move rather quickly southeastward. The main question remains the degree of destabilization which may occur, and thus will introduce only 5%/MRGL risk at this time. ..Goss.. 08/24/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0110 AM CDT Sat Aug 24 2024 Valid 251200Z - 261200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE EASTERN DAKOTAS INTO NORTHWESTERN MINNESOTA... ...SUMMARY... Scattered severe storms may develop across the northern Plains area on Sunday, with more isolated severe potential southwestward into the southern Rockies on Sunday. A couple of strong/marginally severe storms may also occur across the Lower Great Lakes/Upper Ohio Valley vicinity. ...Synopsis... A progressing western U.S. upper trough is forecast to gradually weaken, as it impinges on a persistent central U.S. ridge. The result will be that the trough gets shunted northeastward toward Montana/Wyoming with time. Meanwhile, weak upper troughing will persist over the Northeast. At the surface, a cold front will progress eastward across the Canadian Prairie, and the north-central U.S. with time. By the end of the period, the front should stretch from Minnesota southwestward to northeastern Colorado. ...Northern Plains southwestward to the Four Corners region... As the western U.S. trough advances eastward, large-scale ascent will support scattered thunderstorm development across the Intermountain Region, within a diurnally destabilizing airmass. While CAPE will remain limited, moderate southwesterly flow aloft ahead of the trough will allow some storm organization/longevity at time. This, combined with a deep mixed layer providing support for enhanced downdrafts with the stronger cells, will result in risk for locally severe wind gusts. More substantial severe risk could evolve across portions of the north-central states, where much greater instability will evolve. Though the airmass should remain capped in most areas, ascent may be sufficient to support local cap breaches by late afternoon to allow isolated storm development. If storms develop, upscale growth near convective outflows would be expected, possibly resulting in evening/overnight MCS development. Large hail would be possible with the initial storms, though with locally damaging gusts likely to be the dominant risk. Still, given the capping that is anticipated, and questions whether ascent will be sufficient to allow storm development, will maintain only conditional 15%/SLGT risk at this time. ...Lower Great Lakes/Upper Ohio Valley area... On the western fringe of the northeastern U.S. trough, moderate northwesterly flow aloft may combine with modest afternoon destabilization to support isolated storm development. Assuming this occurs, a few strong gusts would be possible as storms would move rather quickly southeastward. The main question remains the degree of destabilization which may occur, and thus will introduce only 5%/MRGL risk at this time. ..Goss.. 08/24/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1252 AM CDT Sat Aug 24 2024 Valid 241200Z - 251200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE FOUR CORNERS REGION INTO THE CENTRAL HIGH PLAINS...PARTS OF WESTERN MO...AND PARTS OF THE SOUTHERN PLAINS... ...SUMMARY... Strong to locally severe storms are possible today from the Four Corners region northeastward into the central High Plains. Strong to severe storms are also possible across western Missouri and also across western Oklahoma. ...Synopsis... A deep mid/upper-level trough will remain in place over the West today. An embedded mid/upper cyclone is forecast to move southeastward from northern CA into the Great Basin. Downstream, an upper-level anticyclone will remain anchored over the southern Great Plains. One surface low is forecast to gradually deepen across the northern High Plains, while another weak surface low may develop across the south-central High Plains. ...Four Corners region into the central High Plains... The eastern fringe of stronger southwesterly flow aloft (associated with the deep upper trough) will overspread a plume of midlevel moisture from the Four Corners region into the central Rockies. Scattered thunderstorm development is expected across the region this afternoon. Effective shear of 30-40 kt and modest but sufficient buoyancy will support potential for a few loosely organized cells and/or clusters, with a threat of isolated strong to severe gusts. Richer low-level moisture and stronger instability will develop this afternoon across parts of the central High Plains, where moist easterly flow is maintained to the north of a nearly stationary surface boundary. With capping and weaker large-scale ascent expected, storm initiation within this more-unstable regime may be suppressed. However, high-based convection that develops over the higher terrain could spread into the central High Plains by early evening, potentially accompanied by an isolated strong to severe gusts and perhaps some hail. ...Western MO and vicinity... Most guidance suggests an increase in elevated convection near and after 12Z across parts of western MO, driven by low-level warm advection and moistening in the 850-700 mb layer. Effective shear will not be particularly strong, but relatively steep midlevel lapse rates and moderate elevated buoyancy will support potential for a few robust storms. Isolated hail cannot be ruled out with the strongest storms. Also, despite the elevated nature of the convection, initially rather dry profiles below the moist layer could support locally strong gusts. Depending on the coverage and intensity of morning convection, cold-pool development will be possible, which could lead to a southward-propagating cluster across western MO. This scenario remains quite uncertain, but there will be some potential for an isolated damaging-gust threat to spread into southwest MO from late morning into the afternoon. ...Parts of western OK into northwest TX... Despite generally weak large-scale ascent, some guidance suggests potential for isolated to widely scattered thunderstorm development within a very hot/well-mixed environment across parts of western OK into northwest TX late this afternoon into the early evening. With weak deep-layer shear and the influence of the upper ridge, storms will likely remain disorganized, and coverage of storms remains uncertain. However, any stronger storm within this environment would pose a conditional microburst threat. A 5% wind area has been added where relative confidence in storm development is currently greatest. ...Northeast MT into northwest ND... Moderate to locally strong instability may develop this afternoon from far northeast MT into northwest ND, with sufficient deep-layer shear to support storm organization. However, large-scale ascent is expected to remain rather weak across the region, and there is only a very weak signal for diurnal storm development. Some threat for severe hail and/or wind could accompany any robust storm within this regime, but confidence in storm coverage is too low for probabilities at this time. ..Dean/Karstens.. 08/24/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1252 AM CDT Sat Aug 24 2024 Valid 241200Z - 251200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE FOUR CORNERS REGION INTO THE CENTRAL HIGH PLAINS...PARTS OF WESTERN MO...AND PARTS OF THE SOUTHERN PLAINS... ...SUMMARY... Strong to locally severe storms are possible today from the Four Corners region northeastward into the central High Plains. Strong to severe storms are also possible across western Missouri and also across western Oklahoma. ...Synopsis... A deep mid/upper-level trough will remain in place over the West today. An embedded mid/upper cyclone is forecast to move southeastward from northern CA into the Great Basin. Downstream, an upper-level anticyclone will remain anchored over the southern Great Plains. One surface low is forecast to gradually deepen across the northern High Plains, while another weak surface low may develop across the south-central High Plains. ...Four Corners region into the central High Plains... The eastern fringe of stronger southwesterly flow aloft (associated with the deep upper trough) will overspread a plume of midlevel moisture from the Four Corners region into the central Rockies. Scattered thunderstorm development is expected across the region this afternoon. Effective shear of 30-40 kt and modest but sufficient buoyancy will support potential for a few loosely organized cells and/or clusters, with a threat of isolated strong to severe gusts. Richer low-level moisture and stronger instability will develop this afternoon across parts of the central High Plains, where moist easterly flow is maintained to the north of a nearly stationary surface boundary. With capping and weaker large-scale ascent expected, storm initiation within this more-unstable regime may be suppressed. However, high-based convection that develops over the higher terrain could spread into the central High Plains by early evening, potentially accompanied by an isolated strong to severe gusts and perhaps some hail. ...Western MO and vicinity... Most guidance suggests an increase in elevated convection near and after 12Z across parts of western MO, driven by low-level warm advection and moistening in the 850-700 mb layer. Effective shear will not be particularly strong, but relatively steep midlevel lapse rates and moderate elevated buoyancy will support potential for a few robust storms. Isolated hail cannot be ruled out with the strongest storms. Also, despite the elevated nature of the convection, initially rather dry profiles below the moist layer could support locally strong gusts. Depending on the coverage and intensity of morning convection, cold-pool development will be possible, which could lead to a southward-propagating cluster across western MO. This scenario remains quite uncertain, but there will be some potential for an isolated damaging-gust threat to spread into southwest MO from late morning into the afternoon. ...Parts of western OK into northwest TX... Despite generally weak large-scale ascent, some guidance suggests potential for isolated to widely scattered thunderstorm development within a very hot/well-mixed environment across parts of western OK into northwest TX late this afternoon into the early evening. With weak deep-layer shear and the influence of the upper ridge, storms will likely remain disorganized, and coverage of storms remains uncertain. However, any stronger storm within this environment would pose a conditional microburst threat. A 5% wind area has been added where relative confidence in storm development is currently greatest. ...Northeast MT into northwest ND... Moderate to locally strong instability may develop this afternoon from far northeast MT into northwest ND, with sufficient deep-layer shear to support storm organization. However, large-scale ascent is expected to remain rather weak across the region, and there is only a very weak signal for diurnal storm development. Some threat for severe hail and/or wind could accompany any robust storm within this regime, but confidence in storm coverage is too low for probabilities at this time. ..Dean/Karstens.. 08/24/2024 Read more

000
ABPZ20 KNHC 240515
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 PM PDT Fri Aug 23 2024

For the eastern North Pacific...east of 140 degrees west longitude:

Active Systems:
The National Hurricane Center is issuing advisories on Hurricane
Gilma, located well to the west-southwest of the southern tip of
the Baja California peninsula.

Central Portion of the East Pacific (EP92):
Shower and thunderstorm activity remains displaced to the west of an
area of low pressure centered several hundred miles to the southwest
of the southern tip of the Baja California peninsula. Upper-level
winds are forecast to decrease over the low during the next day or
two, and a tropical depression is expected to form this weekend or
early next week while moving toward the west or west-northwest at
around 10 mph.
* Formation chance through 48 hours...high...80 percent.
* Formation chance through 7 days...high...90 percent.

$$
Forecaster Reinhart

5-Day Uncertainty Track last updated Sat, 24 Aug 2024 02:33:58 GMT


Wind Speed Probabilities last updated Sat, 24 Aug 2024 03:29:13 GMT

Issued at 0300 UTC SAT AUG 24 2024 000 FOPZ12 KNHC 240232 PWSEP2 HURRICANE GILMA WIND SPEED PROBABILITIES NUMBER 23 NWS NATIONAL HURRICANE CENTER MIAMI FL EP072024 0300 UTC SAT AUG 24 2024 AT 0300Z THE CENTER OF HURRICANE GILMA WAS LOCATED NEAR LATITUDE 17.5 NORTH...LONGITUDE 128.4 WEST WITH MAXIMUM SUSTAINED WINDS NEAR 90 KTS...105 MPH...165 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 00Z SAT 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 00Z SAT 12Z SAT 00Z SUN 12Z SUN 00Z MON 00Z TUE 00Z WED PERIODS TO TO TO TO TO TO TO 12Z SAT 00Z SUN 12Z SUN 00Z MON 00Z TUE 00Z WED 00Z THU FORECAST HOUR (12) (24) (36) (48) (72) (96) (120) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - LOCATION KT 15N 130W 34 3 3( 6) 2( 8) 1( 9) X( 9) X( 9) X( 9) 20N 130W 34 9 12(21) 2(23) 1(24) X(24) X(24) X(24) 15N 135W 34 X 2( 2) 3( 5) 3( 8) 3(11) X(11) X(11) 20N 135W 34 X 4( 4) 21(25) 27(52) 5(57) X(57) X(57) 20N 135W 50 X X( X) 2( 2) 10(12) 2(14) X(14) X(14) 20N 135W 64 X X( X) X( X) 4( 4) 1( 5) X( 5) X( 5) 15N 140W 34 X X( X) X( X) X( X) 4( 4) 1( 5) X( 5) 20N 140W 34 X X( X) X( X) 3( 3) 24(27) 12(39) X(39) 20N 140W 50 X X( X) X( X) X( X) 6( 6) 3( 9) X( 9) 20N 140W 64 X X( X) X( X) X( X) 1( 1) 1( 2) X( 2) 20N 145W 34 X X( X) X( X) X( X) X( X) 12(12) 6(18) 20N 145W 50 X X( X) X( X) X( X) X( X) 2( 2) 1( 3) 20N 150W 34 X X( X) X( X) X( X) X( X) X( X) 4( 4) 20N 151W 34 X X( X) X( X) X( X) X( X) X( X) 3( 3) $$ FORECASTER KELLY

Issued at 500 PM HST Fri Aug 23 2024 000 WTPZ42 KNHC 240232 TCDEP2 Hurricane Gilma Discussion Number 23 NWS National Hurricane Center Miami FL EP072024 500 PM HST Fri Aug 23 2024 Gilma's satellite depiction has changed very little since earlier today, as the eye has become filled and now the center resides beneath the central dense overcast (CDO) on both visible and infrared imagery. Deep convection continues to burst within the inner core with cold cloud tops to near -80 C, with generally good outflow in all directions. The subjective and objective intensity estimates have remained steady with this advisory as well, with a current intensity (CI) of 5.0 from both SAB and TAFB. Given the steady state of satellite imagery and the intensity estimates, the initial intensity is held at 90 kt for this advisory. The hurricane is continuing to move generally westward at an initial motion of 280/8 kt. A ridge has started to build to the north of Gilma, which will keep the system on a generally westward track, with a gradual increase in forward motion. The track model guidance is in fairly good agreement with the general direction the system moves, however how fast that increase in forward speed occurs leads to some along-track differences in the model suite, particularly at the end of the forecast period. The official NHC track forecast is near the previous forecast, just nudged slightly southward and faster, near the consensus aids. Gilma is in a low wind shear environment, however the system is about to run into cooler sea surface temperatures with very little ocean heat content beyond the next 24 h or so. As the system moves over cooler waters it will also encounter a much drier and stable airmass. These changes in oceanic and atmospheric conditions will lead to gradual weakening over the next 24 hours followed by an increasing rate of weakening through the end of the period. Towards the end of the forecast period, conditions continue to become unfavorable with upper-level westerly wind shear increasing, and the GFS depicts the system struggling to produce convection, becoming a remnant low at 120 h. The official NHC intensity forecast is similar to the previous advisory, near the simple consensus intensity aids. FORECAST POSITIONS AND MAX WINDS INIT 24/0300Z 17.5N 128.4W 90 KT 105 MPH 12H 24/1200Z 17.7N 129.7W 85 KT 100 MPH 24H 25/0000Z 18.0N 131.5W 80 KT 90 MPH 36H 25/1200Z 18.2N 133.4W 75 KT 85 MPH 48H 26/0000Z 18.4N 135.1W 70 KT 80 MPH 60H 26/1200Z 18.6N 137.0W 60 KT 70 MPH 72H 27/0000Z 18.9N 139.0W 50 KT 60 MPH 96H 28/0000Z 19.4N 143.7W 40 KT 45 MPH 120H 29/0000Z 20.3N 148.7W 30 KT 35 MPH...POST-TROP/REMNT LOW $$ Forecaster Kelly

Issued at 0300 UTC SAT AUG 24 2024 000 WTPZ22 KNHC 240231 TCMEP2 HURRICANE GILMA FORECAST/ADVISORY NUMBER 23 NWS NATIONAL HURRICANE CENTER MIAMI FL EP072024 0300 UTC SAT AUG 24 2024 HURRICANE CENTER LOCATED NEAR 17.5N 128.4W AT 24/0300Z POSITION ACCURATE WITHIN 20 NM PRESENT MOVEMENT TOWARD THE WEST OR 280 DEGREES AT 8 KT ESTIMATED MINIMUM CENTRAL PRESSURE 970 MB MAX SUSTAINED WINDS 90 KT WITH GUSTS TO 110 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 150NW. 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 17.5N 128.4W AT 24/0300Z AT 24/0000Z CENTER WAS LOCATED NEAR 17.4N 128.0W FORECAST VALID 24/1200Z 17.7N 129.7W MAX WIND 85 KT...GUSTS 105 KT. 64 KT... 25NE 20SE 20SW 25NW. 50 KT... 50NE 40SE 40SW 50NW. 34 KT... 90NE 80SE 80SW 90NW. FORECAST VALID 25/0000Z 18.0N 131.5W MAX WIND 80 KT...GUSTS 100 KT. 64 KT... 25NE 20SE 20SW 25NW. 50 KT... 40NE 30SE 30SW 40NW. 34 KT... 90NE 70SE 70SW 90NW. FORECAST VALID 25/1200Z 18.2N 133.4W MAX WIND 75 KT...GUSTS 90 KT. 64 KT... 20NE 15SE 15SW 20NW. 50 KT... 40NE 30SE 30SW 40NW. 34 KT... 90NE 60SE 60SW 90NW. FORECAST VALID 26/0000Z 18.4N 135.1W MAX WIND 70 KT...GUSTS 85 KT. 64 KT... 20NE 10SE 10SW 20NW. 50 KT... 40NE 30SE 30SW 40NW. 34 KT... 80NE 50SE 50SW 80NW. FORECAST VALID 26/1200Z 18.6N 137.0W MAX WIND 60 KT...GUSTS 75 KT. 50 KT... 30NE 20SE 20SW 30NW. 34 KT... 80NE 50SE 40SW 70NW. FORECAST VALID 27/0000Z 18.9N 139.0W MAX WIND 50 KT...GUSTS 60 KT. 50 KT... 30NE 20SE 20SW 30NW. 34 KT... 70NE 40SE 40SW 70NW. 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 28/0000Z 19.4N 143.7W MAX WIND 40 KT...GUSTS 50 KT. 34 KT... 60NE 30SE 30SW 60NW. OUTLOOK VALID 29/0000Z 20.3N 148.7W...POST-TROP/REMNT LOW MAX WIND 30 KT...GUSTS 40 KT. REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 17.5N 128.4W NEXT ADVISORY AT 24/0900Z $$ FORECASTER KELLY

Issued at 500 PM HST Fri Aug 23 2024 000 WTPZ32 KNHC 240231 TCPEP2 BULLETIN Hurricane Gilma Advisory Number 23 NWS National Hurricane Center Miami FL EP072024 500 PM HST Fri Aug 23 2024 ...GILMA CONTINUES MOVING WESTWARD... SUMMARY OF 500 PM HST...0300 UTC...INFORMATION ---------------------------------------------- LOCATION...17.5N 128.4W ABOUT 1255 MI...2020 KM WSW OF THE SOUTHERN TIP OF BAJA CALIFORNIA ABOUT 1750 MI...2820 KM E OF HILO HAWAII MAXIMUM SUSTAINED WINDS...105 MPH...165 KM/H PRESENT MOVEMENT...W OR 280 DEGREES AT 9 MPH...15 KM/H MINIMUM CENTRAL PRESSURE...970 MB...28.65 INCHES WATCHES AND WARNINGS -------------------- There are no coastal watches or warnings in effect. DISCUSSION AND OUTLOOK ---------------------- At 500 PM HST (0300 UTC), the center of Hurricane Gilma was located near latitude 17.5 North, longitude 128.4 West. Gilma is moving toward the west near 9 mph (15 km/h). A generally westward motion with an increase in forward speed is expected during the next couple of days. Maximum sustained winds are near 105 mph (165 km/h) with higher gusts. Weakening is forecast during the next several days, but Gilma is expected to remain a hurricane through the 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 970 mb (28.65 inches). HAZARDS AFFECTING LAND ---------------------- None NEXT ADVISORY ------------- Next complete advisory at 1100 PM HST. $$ Forecaster Kelly

...GILMA CONTINUES MOVING WESTWARD... As of 5:00 PM HST Fri Aug 23 the center of Gilma was located near 17.5, -128.4 with movement W at 9 mph. The minimum central pressure was 970 mb with maximum sustained winds of about 105 mph.

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0800 PM CDT Fri Aug 23 2024 Valid 240100Z - 241200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR A SMALL PART OF NORTHWEST/NORTH-CENTRAL MT... ...SUMMARY... A threat for severe gusts will continue across parts of Montana through mid evening. Other strong to severe storms remain possible across eastern Utah and western Colorado, and also across the central High Plains. ...Montana... Scattered thunderstorms with a history of producing measured severe gusts are quickly moving northward across northwest MT early this evening, and will soon move across the international border. Farther east, a storm cluster across central MT may continue to pose a threat of severe gusts as it moves through a relatively warm and well-mixed environment. A separate cluster of storms across northeast MT may continue to pose a short-term threat of isolated hail and severe gusts, before increasing MLCINH reduces convective potential later tonight. ...Central High Plains into western MO... A small outflow-driven cluster of storms is moving across parts of the central High Plains early this evening. A short-term threat for isolated severe gusts and hail may spread eastward through mid evening, as the cluster moves through a moderately unstable and marginally sheared environment. Increasing MLCINH with time may eventually result in a weakening trend, though stronger elevated convection may persist through the night as the remnant cluster moves eastward. Some increase in elevated storms will also be possible near the end of the period across western MO, within a low-level warm-advection regime. Moderate MUCAPE could support a few stronger storms with small hail and gusty winds, but severe potential prior to 12Z within this regime appears relatively limited. ...Eastern UT into western CO... A couple stronger storms may persist through at least part of the evening from eastern UT into western CO, where MLCAPE in excess of 500 J/kg and favorable deep-layer shear may support transient supercell structures capable of isolated hail and strong/severe gusts. ..Dean.. 08/24/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0800 PM CDT Fri Aug 23 2024 Valid 240100Z - 241200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR A SMALL PART OF NORTHWEST/NORTH-CENTRAL MT... ...SUMMARY... A threat for severe gusts will continue across parts of Montana through mid evening. Other strong to severe storms remain possible across eastern Utah and western Colorado, and also across the central High Plains. ...Montana... Scattered thunderstorms with a history of producing measured severe gusts are quickly moving northward across northwest MT early this evening, and will soon move across the international border. Farther east, a storm cluster across central MT may continue to pose a threat of severe gusts as it moves through a relatively warm and well-mixed environment. A separate cluster of storms across northeast MT may continue to pose a short-term threat of isolated hail and severe gusts, before increasing MLCINH reduces convective potential later tonight. ...Central High Plains into western MO... A small outflow-driven cluster of storms is moving across parts of the central High Plains early this evening. A short-term threat for isolated severe gusts and hail may spread eastward through mid evening, as the cluster moves through a moderately unstable and marginally sheared environment. Increasing MLCINH with time may eventually result in a weakening trend, though stronger elevated convection may persist through the night as the remnant cluster moves eastward. Some increase in elevated storms will also be possible near the end of the period across western MO, within a low-level warm-advection regime. Moderate MUCAPE could support a few stronger storms with small hail and gusty winds, but severe potential prior to 12Z within this regime appears relatively limited. ...Eastern UT into western CO... A couple stronger storms may persist through at least part of the evening from eastern UT into western CO, where MLCAPE in excess of 500 J/kg and favorable deep-layer shear may support transient supercell structures capable of isolated hail and strong/severe gusts. ..Dean.. 08/24/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0800 PM CDT Fri Aug 23 2024 Valid 240100Z - 241200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR A SMALL PART OF NORTHWEST/NORTH-CENTRAL MT... ...SUMMARY... A threat for severe gusts will continue across parts of Montana through mid evening. Other strong to severe storms remain possible across eastern Utah and western Colorado, and also across the central High Plains. ...Montana... Scattered thunderstorms with a history of producing measured severe gusts are quickly moving northward across northwest MT early this evening, and will soon move across the international border. Farther east, a storm cluster across central MT may continue to pose a threat of severe gusts as it moves through a relatively warm and well-mixed environment. A separate cluster of storms across northeast MT may continue to pose a short-term threat of isolated hail and severe gusts, before increasing MLCINH reduces convective potential later tonight. ...Central High Plains into western MO... A small outflow-driven cluster of storms is moving across parts of the central High Plains early this evening. A short-term threat for isolated severe gusts and hail may spread eastward through mid evening, as the cluster moves through a moderately unstable and marginally sheared environment. Increasing MLCINH with time may eventually result in a weakening trend, though stronger elevated convection may persist through the night as the remnant cluster moves eastward. Some increase in elevated storms will also be possible near the end of the period across western MO, within a low-level warm-advection regime. Moderate MUCAPE could support a few stronger storms with small hail and gusty winds, but severe potential prior to 12Z within this regime appears relatively limited. ...Eastern UT into western CO... A couple stronger storms may persist through at least part of the evening from eastern UT into western CO, where MLCAPE in excess of 500 J/kg and favorable deep-layer shear may support transient supercell structures capable of isolated hail and strong/severe gusts. ..Dean.. 08/24/2024 Read more

MD 1983 CONCERNING SEVERE THUNDERSTORM WATCH 645... FOR WESTERN MONTANA
Mesoscale Discussion 1983 NWS Storm Prediction Center Norman OK 0604 PM CDT Fri Aug 23 2024 Areas affected...Western Montana Concerning...Severe Thunderstorm Watch 645... Valid 232304Z - 240100Z The severe weather threat for Severe Thunderstorm Watch 645 continues. SUMMARY...Severe wind gust potential continues with convection this evening. DISCUSSION...Satellite imagery depicts a well-defined short-wave trough, extending from northeast OR-ID-extreme western WY, lifting north across the northern Rockies. Large-scale height falls are noted ahead of this feature as 500mb flow on the order of 50kt translates across the Bitter Roots into western MT. An arcing corridor of scattered robust convection has developed ahead of the short wave, and while this activity is developing within a weak-instability airmass, severe gusts have been common. Over the next few hours it appears the primary area of concern will extend across northern portions of ww645 where instability has yet to be overturned. ..Darrow.. 08/23/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...BYZ...RIW...TFX...PIH...MSO... LAT...LON 44641447 48961445 48961029 44651061 44641447 Read more

MD 1981 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR EASTERN MONTANA
Mesoscale Discussion 1981 NWS Storm Prediction Center Norman OK 0539 PM CDT Fri Aug 23 2024 Areas affected...Eastern Montana Concerning...Severe potential...Watch unlikely Valid 232239Z - 240045Z Probability of Watch Issuance...20 percent SUMMARY...Isolated threat for wind/hail will be noted with convection this evening. Watch is not currently anticipated. DISCUSSION...Mid-level heights are being suppressed a bit over central/eastern MT along the eastern influence of a short-wave trough that is ejecting north across the northern Rockies. While large-scale influence of this feature will likely remain focused across western MT, strong boundary-layer heating has contributed to steep 0-3km lapse rates as temperature are now well into the mid 90s. Convective temperature have been breached, and negligible CINH is supported by thickening boundary-layer cu field, and isolated thunderstorms between GGW-OLF. This clustering is occurring within a zone of favorable low-level confluence, and along an instability axis where MLCAPE values are in excess of 2000 J/kg. There is some concern a few robust updrafts will evolve across eastern MT over the next few hours as surface-6km bulk shear is more than adequate for sustaining organized updrafts; however, it's not entirely clear how many storms will evolve. Another concern is any storms that linger beyond sunset will eventually be aided by a strengthening LLJ. Will continue to monitor this region, but at this time a watch is not currently anticipated. ..Darrow/Gleason.. 08/23/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...BYZ...GGW... LAT...LON 49010432 46200421 46210675 48800743 49010432 Read more

WW 0645 Status Updates
STATUS REPORT ON WW 645 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 15 NNW LVM TO 25 SSW GTF TO 45 SSW CTB TO 40 SE GPI TO 35 SSW GPI. ..SPC..08/24/24 ATTN...WFO...TFX...MSO... STATUS REPORT FOR WS 645 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS MTC005-013-015-027-029-035-041-045-051-053-059-073-099-101- 240140- MT . MONTANA COUNTIES INCLUDED ARE BLAINE CASCADE CHOUTEAU FERGUS FLATHEAD GLACIER HILL JUDITH BASIN LIBERTY LINCOLN MEAGHER PONDERA TETON TOOLE 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

WW 0645 Status Updates
STATUS REPORT ON WW 645 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 15 NNW LVM TO 25 SSW GTF TO 45 SSW CTB TO 40 SE GPI TO 35 SSW GPI. ..SPC..08/24/24 ATTN...WFO...TFX...MSO... STATUS REPORT FOR WS 645 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS MTC005-013-015-027-029-035-041-045-051-053-059-073-099-101- 240140- MT . MONTANA COUNTIES INCLUDED ARE BLAINE CASCADE CHOUTEAU FERGUS FLATHEAD GLACIER HILL JUDITH BASIN LIBERTY LINCOLN MEAGHER PONDERA TETON TOOLE 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

WW 645 SEVERE TSTM MT 232055Z - 240300Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 645 NWS Storm Prediction Center Norman OK 255 PM MDT Fri Aug 23 2024 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Western and Central Montana * Effective this Friday afternoon and evening from 255 PM until 900 PM MDT. * Primary threats include... Isolated significant damaging wind gusts to 75 mph possible SUMMARY...Scattered thunderstorms will continue to develop and move north-northeastward across the region through early evening, with severe-caliber wind gusts a possibility. The severe thunderstorm watch area is approximately along and 95 statute miles east and west of a line from 25 miles north of Cut Bank MT to 40 miles south of Dillon MT. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU5). 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. && AVIATION...A few severe thunderstorms with hail surface and aloft to 1 inch. Extreme turbulence and surface wind gusts to 65 knots. A few cumulonimbi with maximum tops to 450. Mean storm motion vector 20030. ...Guyer Read more