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WW 666 SEVERE TSTM MT NE SD WY 042005Z - 050200Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 666 NWS Storm Prediction Center Norman OK 205 PM MDT Mon Sep 4 2023 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Southeast Montana Nebraska Panhandle Western South Dakota Eastern Wyoming * Effective this Monday afternoon and evening from 205 PM until 800 PM MDT. * Primary threats include... Scattered damaging winds and isolated significant gusts to 75 mph possible Isolated large hail events to 1.5 inches in diameter possible SUMMARY...Strong to severe thunderstorms are expected to develop through mid/late afternoon across the region. Storms will initially be capable of large hail and damaging winds, with severe wind potential likely to increase by evening into and across western South Dakota. The severe thunderstorm watch area is approximately along and 80 statute miles east and west of a line from 35 miles northwest of Buffalo SD to 40 miles southwest of Scottsbluff NE. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU6). 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 1.5 inches. Extreme turbulence and surface wind gusts to 65 knots. A few cumulonimbi with maximum tops to 550. Mean storm motion vector 23035. ...Guyer Read more

WW 0667 Status Updates
STATUS FOR WATCH 0667 HAS NOT BEEN ISSUED YET Read more

WW 0667 Status Updates
STATUS FOR WATCH 0667 HAS NOT BEEN ISSUED YET Read more

WW 667 SEVERE TSTM ND SD 042225Z - 050400Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 667 NWS Storm Prediction Center Norman OK 525 PM CDT Mon Sep 4 2023 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Southern North Dakota North-central South Dakota * Effective this Monday afternoon and evening from 525 PM until 1100 PM CDT. * Primary threats include... Scattered damaging winds and isolated significant gusts to 90 mph likely Isolated large hail events to 1.5 inches in diameter possible SUMMARY...A small cluster over northwest South Dakota with a history of severe wind gusts should intensify and likely produce a confined swath of severe into portions of southern North Dakota through late evening. The severe thunderstorm watch area is approximately along and 85 statute miles either side of a line from 25 miles north northwest of Bismarck ND to 55 miles east southeast of Mobridge SD. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU7). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Severe Thunderstorm Watch means conditions are favorable for severe thunderstorms in and close to the watch area. Persons in these areas should be on the lookout for threatening weather conditions and listen for later statements and possible warnings. Severe thunderstorms can and occasionally do produce tornadoes. && OTHER WATCH INFORMATION...CONTINUE...WW 666... AVIATION...A few severe thunderstorms with hail surface and aloft to 1.5 inches. Extreme turbulence and surface wind gusts to 80 knots. A few cumulonimbi with maximum tops to 450. Mean storm motion vector 24040. ...Grams Read more

WW 667 SEVERE TSTM ND SD 042225Z - 050400Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 667 NWS Storm Prediction Center Norman OK 525 PM CDT Mon Sep 4 2023 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Southern North Dakota North-central South Dakota * Effective this Monday afternoon and evening from 525 PM until 1100 PM CDT. * Primary threats include... Scattered damaging winds and isolated significant gusts to 90 mph likely Isolated large hail events to 1.5 inches in diameter possible SUMMARY...A small cluster over northwest South Dakota with a history of severe wind gusts should intensify and likely produce a confined swath of severe into portions of southern North Dakota through late evening. The severe thunderstorm watch area is approximately along and 85 statute miles either side of a line from 25 miles north northwest of Bismarck ND to 55 miles east southeast of Mobridge SD. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU7). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Severe Thunderstorm Watch means conditions are favorable for severe thunderstorms in and close to the watch area. Persons in these areas should be on the lookout for threatening weather conditions and listen for later statements and possible warnings. Severe thunderstorms can and occasionally do produce tornadoes. && OTHER WATCH INFORMATION...CONTINUE...WW 666... AVIATION...A few severe thunderstorms with hail surface and aloft to 1.5 inches. Extreme turbulence and surface wind gusts to 80 knots. A few cumulonimbi with maximum tops to 450. Mean storm motion vector 24040. ...Grams Read more

MD 2080 CONCERNING SEVERE THUNDERSTORM WATCH 666... FOR NORTHWEST AND NORTH-CENTRAL SD...SOUTHERN AND CENTRAL ND
Mesoscale Discussion 2080 NWS Storm Prediction Center Norman OK 0452 PM CDT Mon Sep 04 2023 Areas affected...northwest and north-central SD...southern and central ND Concerning...Severe Thunderstorm Watch 666... Valid 042152Z - 042345Z The severe weather threat for Severe Thunderstorm Watch 666 continues. SUMMARY...Scattered severe gusts are probable across the northeast part of severe thunderstorm watch #666 as a band of storms moves northeastward. A downstream severe thunderstorm watch is expected within the next hour in parts of northern SD and southern ND. Peak gusts with the most intense downdrafts are forecast to range 70-90 mph through 01 UTC (8pm CDT/7pm MDT) over northern SD and southern ND. DISCUSSION...Radar mosaic late this afternoon shows an intensifying band of storms over western SD. Surface analysis ahead of this activity indicates temperatures are in the 95-100 deg F range south of a southwest-northeast oriented surface trough. The airmass where the ongoing storms are located in western SD is adequately moist (mid 50s deg F dewpoints) but relatively dry compared to south-central ND where dewpoints are in the lower 60s. As a result, PW increases from southwest to northeast. This increase in moisture will probably result in both storms moving in a more favorable environment of buoyancy and moisture for evaporatively cooled downdrafts. It appears the most intense phase of the developing squall line will commence over the next few hours as storms move into northern SD and into southern ND. The negatively tilted mid-level shortwave trough over WY will continue to pivot eastward towards the Dakotas this evening. The combination of very steep low to mid-level lapse rates, a linear storm mode, and appreciable large-scale forcing for ascent will favor scattered severe gusts through the evening across the Dakotas with the squall line. Peak gusts are forecast to range from 70-90 mph. ..Smith.. 09/04/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...FGF...ABR...BIS...UNR... LAT...LON 44300172 44250220 44340250 45460364 45700370 45950357 47300105 47409982 47229892 46789830 46129834 45419893 44300172 Read more

MD 2080 CONCERNING SEVERE THUNDERSTORM WATCH 666... FOR NORTHWEST AND NORTH-CENTRAL SD...SOUTHERN AND CENTRAL ND
Mesoscale Discussion 2080 NWS Storm Prediction Center Norman OK 0452 PM CDT Mon Sep 04 2023 Areas affected...northwest and north-central SD...southern and central ND Concerning...Severe Thunderstorm Watch 666... Valid 042152Z - 042345Z The severe weather threat for Severe Thunderstorm Watch 666 continues. SUMMARY...Scattered severe gusts are probable across the northeast part of severe thunderstorm watch #666 as a band of storms moves northeastward. A downstream severe thunderstorm watch is expected within the next hour in parts of northern SD and southern ND. Peak gusts with the most intense downdrafts are forecast to range 70-90 mph through 01 UTC (8pm CDT/7pm MDT) over northern SD and southern ND. DISCUSSION...Radar mosaic late this afternoon shows an intensifying band of storms over western SD. Surface analysis ahead of this activity indicates temperatures are in the 95-100 deg F range south of a southwest-northeast oriented surface trough. The airmass where the ongoing storms are located in western SD is adequately moist (mid 50s deg F dewpoints) but relatively dry compared to south-central ND where dewpoints are in the lower 60s. As a result, PW increases from southwest to northeast. This increase in moisture will probably result in both storms moving in a more favorable environment of buoyancy and moisture for evaporatively cooled downdrafts. It appears the most intense phase of the developing squall line will commence over the next few hours as storms move into northern SD and into southern ND. The negatively tilted mid-level shortwave trough over WY will continue to pivot eastward towards the Dakotas this evening. The combination of very steep low to mid-level lapse rates, a linear storm mode, and appreciable large-scale forcing for ascent will favor scattered severe gusts through the evening across the Dakotas with the squall line. Peak gusts are forecast to range from 70-90 mph. ..Smith.. 09/04/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...FGF...ABR...BIS...UNR... LAT...LON 44300172 44250220 44340250 45460364 45700370 45950357 47300105 47409982 47229892 46789830 46129834 45419893 44300172 Read more

WW 0666 Status Updates
STATUS REPORT ON WW 666 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..LYONS..09/04/23 ATTN...WFO...BYZ...CYS...UNR...RIW... STATUS REPORT FOR WS 666 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS MTC011-075-042240- MT . MONTANA COUNTIES INCLUDED ARE CARTER POWDER RIVER NEC007-013-045-123-157-165-042240- NE . NEBRASKA COUNTIES INCLUDED ARE BANNER BOX BUTTE DAWES MORRILL SCOTTS BLUFF SIOUX SDC019-033-047-055-063-081-093-102-103-105-137-042240- SD . SOUTH DAKOTA COUNTIES INCLUDED ARE BUTTE CUSTER FALL RIVER HAAKON HARDING LAWRENCE MEADE OGLALA LAKOTA PENNINGTON PERKINS ZIEBACH Read more

5-Day Uncertainty Track last updated Mon, 04 Sep 2023 20:39:10 GMT


Wind Speed Probabilities last updated Mon, 04 Sep 2023 21:30:27 GMT

Issued at 400 PM CDT Mon Sep 04 2023 000 WTPZ41 KNHC 042037 TCDEP1 Tropical Depression Eleven-E Discussion Number 1 NWS National Hurricane Center Miami FL EP112023 400 PM CDT Mon Sep 04 2023 Recent visible satellite imagery indicates that the disturbance located south of the southwestern coast of Mexico (93E) has developed a well-defined circulation. In addition, a prominent band of deep convection has formed around its western half. The latest Dvorak classification Data-T from TAFB is a 2.0, which corresponds to 30 kt. Based on the available data, the system has been classified as Tropical Depression Eleven. The depression is moving westward, with an estimated forward speed of 10 kt. While all models agree that the cyclone will head generally west-northwestward for the next 5 or more days, moving well south and west of Mexico, there is substantial disagreement on its forward speed. The main source of this uncertainty appears to be differences in the strength of the primary steering mechanism influencing the depression, a deep ridge centered over northern Mexico and the southwestern U.S. that extends over the eastern Pacific. The stronger the ridge, the faster the cyclone will move. The uncertainty in the track forecast is much higher than normal by the end of the forecast, with even the consensus models relatively far apart. At day 5, the gap between HCCA and TVCN is more than 150 n mi. As a course of least regret, the NHC forecast doesn't favor any one model or consensus aid, generally staying between the simple and corrected consensus tracks. The environment looks very conducive for strengthening, possibly significantly so. SHIPS-derived shear is forecast to be near or below 10 kt through day 5, with plenty of moisture and warm SSTs available as well. It will likely take a day or so for the depression to get sufficiently organized to take advantage of this environment, so only slow strengthening is forecast for the first 24 h. Looking beyond that, the SHIPS-RII and DTOPS rapid intensification (RI) probabilities for 65kt/72 h are both above 60 percent. The NHC forecast explicitly shows RI starting at 36 h and continuing through 72 h. While there is spread at just how strong the cyclone will get, most models suggest its peak will come between 72 and 96 h, so a peak intensity higher than what the NHC forecast shows is definitely possible. Beginning at 96 h, the cyclone should begin to quickly spin down as it moves over cooler waters. FORECAST POSITIONS AND MAX WINDS INIT 04/2100Z 12.5N 104.2W 30 KT 35 MPH 12H 05/0600Z 12.8N 105.3W 35 KT 40 MPH 24H 05/1800Z 13.3N 106.7W 40 KT 45 MPH 36H 06/0600Z 13.9N 108.2W 50 KT 60 MPH 48H 06/1800Z 14.6N 110.2W 60 KT 70 MPH 60H 07/0600Z 15.5N 112.5W 80 KT 90 MPH 72H 07/1800Z 16.5N 114.8W 95 KT 110 MPH 96H 08/1800Z 19.0N 119.5W 100 KT 115 MPH 120H 09/1800Z 21.5N 124.5W 75 KT 85 MPH $$ Forecaster D. Zelinsky

Issued at 2100 UTC MON SEP 04 2023 000 FOPZ11 KNHC 042037 PWSEP1 TROPICAL DEPRESSION ELEVEN-E WIND SPEED PROBABILITIES NUMBER 1 NWS NATIONAL HURRICANE CENTER MIAMI FL EP112023 2100 UTC MON SEP 04 2023 AT 2100Z THE CENTER OF TROPICAL DEPRESSION ELEVEN-E WAS LOCATED NEAR LATITUDE 12.5 NORTH...LONGITUDE 104.2 WEST WITH MAXIMUM SUSTAINED WINDS NEAR 30 KTS...35 MPH...55 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 18Z MON 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 18Z MON 06Z TUE 18Z TUE 06Z WED 18Z WED 18Z THU 18Z FRI PERIODS TO TO TO TO TO TO TO 06Z TUE 18Z TUE 06Z WED 18Z WED 18Z THU 18Z FRI 18Z SAT FORECAST HOUR (12) (24) (36) (48) (72) (96) (120) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - LOCATION KT 15N 105W 34 1 1( 2) 2( 4) 1( 5) X( 5) X( 5) X( 5) CLIPPERTON IS 34 X 1( 1) 1( 2) 2( 4) 1( 5) X( 5) X( 5) 10N 110W 34 X X( X) 1( 1) 2( 3) 1( 4) X( 4) X( 4) 15N 110W 34 X 1( 1) 9(10) 53(63) 13(76) X(76) X(76) 15N 110W 50 X X( X) X( X) 24(24) 10(34) X(34) X(34) 15N 110W 64 X X( X) X( X) 7( 7) 7(14) X(14) X(14) 20N 110W 34 X X( X) X( X) 1( 1) 3( 4) X( 4) X( 4) ISLA SOCORRO 34 X X( X) X( X) 3( 3) 10(13) 1(14) X(14) ISLA CLARION 34 X X( X) X( X) 1( 1) 43(44) 14(58) X(58) ISLA CLARION 50 X X( X) X( X) X( X) 13(13) 12(25) X(25) ISLA CLARION 64 X X( X) X( X) X( X) 5( 5) 7(12) X(12) 15N 115W 34 X X( X) X( X) 2( 2) 49(51) 4(55) X(55) 15N 115W 50 X X( X) X( X) X( X) 18(18) 4(22) X(22) 15N 115W 64 X X( X) X( X) X( X) 8( 8) 1( 9) X( 9) 20N 115W 34 X X( X) X( X) X( X) 11(11) 17(28) X(28) 20N 115W 50 X X( X) X( X) X( X) X( X) 5( 5) X( 5) 20N 115W 64 X X( X) X( X) X( X) X( X) 2( 2) X( 2) 15N 120W 34 X X( X) X( X) X( X) 1( 1) 11(12) 1(13) 15N 120W 50 X X( X) X( X) X( X) X( X) 2( 2) X( 2) 15N 120W 64 X X( X) X( X) X( X) X( X) 1( 1) X( 1) 20N 120W 34 X X( X) X( X) X( X) X( X) 55(55) 21(76) 20N 120W 50 X X( X) X( X) X( X) X( X) 26(26) 19(45) 20N 120W 64 X X( X) X( X) X( X) X( X) 12(12) 15(27) 25N 120W 34 X X( X) X( X) X( X) X( X) 1( 1) 6( 7) 20N 125W 34 X X( X) X( X) X( X) X( X) 2( 2) 35(37) 20N 125W 50 X X( X) X( X) X( X) X( X) X( X) 11(11) 20N 125W 64 X X( X) X( X) X( X) X( X) X( X) 5( 5) 25N 125W 34 X X( X) X( X) X( X) X( X) X( X) 14(14) 25N 125W 50 X X( X) X( X) X( X) X( X) X( X) 3( 3) 25N 125W 64 X X( X) X( X) X( X) X( X) X( X) 1( 1) 20N 130W 34 X X( X) X( X) X( X) X( X) X( X) 3( 3) $$ FORECASTER D. ZELINSKY

Issued at 400 PM CDT Mon Sep 04 2023 000 WTPZ31 KNHC 042036 TCPEP1 BULLETIN Tropical Depression Eleven-E Advisory Number 1 NWS National Hurricane Center Miami FL EP112023 400 PM CDT Mon Sep 04 2023 ...TROPICAL DEPRESSION FORMS WELL SOUTH OF MEXICO... ...FORECAST TO BECOME A HURRICANE OVER THE CENTRAL PORTION OF THE BASIN LATER THIS WEEK... SUMMARY OF 400 PM CDT...2100 UTC...INFORMATION ---------------------------------------------- LOCATION...12.5N 104.2W ABOUT 810 MI...1305 KM SSE OF THE SOUTHERN TIP OF BAJA CALIFORNIA MAXIMUM SUSTAINED WINDS...35 MPH...55 KM/H PRESENT MOVEMENT...W OR 280 DEGREES AT 12 MPH...19 KM/H MINIMUM CENTRAL PRESSURE...1007 MB...29.74 INCHES WATCHES AND WARNINGS -------------------- There are no coastal watches or warnings in effect. DISCUSSION AND OUTLOOK ---------------------- At 400 PM CDT (2100 UTC), the center of Tropical Depression Eleven-E was located near latitude 12.5 North, longitude 104.2 West. The depression is moving toward the west near 12 mph (19 km/h). A generally west-northwestward motion is expected for the next several days. The depression is forecast to stay well south and west of Mexico. Maximum sustained winds are near 35 mph (55 km/h) with higher gusts. Strengthening is likely. A relatively slow rate of intensification is expected for the next day or so, followed by rapid strengthening beginning by the middle of the week. The estimated minimum central pressure is 1007 mb (29.74 inches). HAZARDS AFFECTING LAND ---------------------- None NEXT ADVISORY ------------- Next complete advisory at 1000 PM CDT. $$ Forecaster D. Zelinsky

...TROPICAL DEPRESSION FORMS WELL SOUTH OF MEXICO... ...FORECAST TO BECOME A HURRICANE OVER THE CENTRAL PORTION OF THE BASIN LATER THIS WEEK... As of 4:00 PM CDT Mon Sep 4 the center of Eleven-E was located near 12.5, -104.2 with movement W at 12 mph. The minimum central pressure was 1007 mb with maximum sustained winds of about 35 mph.

Issued at 2100 UTC MON SEP 04 2023 000 WTPZ21 KNHC 042036 TCMEP1 TROPICAL DEPRESSION ELEVEN-E FORECAST/ADVISORY NUMBER 1 NWS NATIONAL HURRICANE CENTER MIAMI FL EP112023 2100 UTC MON SEP 04 2023 NOTICE... LAND-BASED TROPICAL CYCLONE WATCHES AND WARNINGS ARE NO LONGER INCLUDED IN THE TROPICAL CYCLONE FORECAST/ADVISORY...(TCM). CURRENT LAND-BASED COASTAL WATCHES AND WARNINGS CAN BE FOUND IN THE MOST RECENTLY ISSUED TROPICAL CYCLONE PUBLIC ADVISORY...(TCP). TROPICAL DEPRESSION CENTER LOCATED NEAR 12.5N 104.2W AT 04/2100Z POSITION ACCURATE WITHIN 45 NM PRESENT MOVEMENT TOWARD THE WEST OR 280 DEGREES AT 10 KT ESTIMATED MINIMUM CENTRAL PRESSURE 1007 MB MAX SUSTAINED WINDS 30 KT WITH GUSTS TO 40 KT. 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 12.5N 104.2W AT 04/2100Z AT 04/1800Z CENTER WAS LOCATED NEAR 12.4N 103.8W FORECAST VALID 05/0600Z 12.8N 105.3W MAX WIND 35 KT...GUSTS 45 KT. 34 KT... 40NE 0SE 0SW 40NW. FORECAST VALID 05/1800Z 13.3N 106.7W MAX WIND 40 KT...GUSTS 50 KT. 34 KT... 60NE 70SE 0SW 60NW. FORECAST VALID 06/0600Z 13.9N 108.2W MAX WIND 50 KT...GUSTS 60 KT. 50 KT... 40NE 0SE 0SW 0NW. 34 KT...100NE 100SE 70SW 70NW. FORECAST VALID 06/1800Z 14.6N 110.2W MAX WIND 60 KT...GUSTS 75 KT. 50 KT... 40NE 30SE 20SW 40NW. 34 KT...140NE 150SE 80SW 90NW. FORECAST VALID 07/0600Z 15.5N 112.5W MAX WIND 80 KT...GUSTS 100 KT. 50 KT... 50NE 50SE 30SW 50NW. 34 KT...160NE 160SE 90SW 110NW. FORECAST VALID 07/1800Z 16.5N 114.8W MAX WIND 95 KT...GUSTS 115 KT. 50 KT... 60NE 60SE 30SW 50NW. 34 KT...160NE 160SE 90SW 130NW. 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 08/1800Z 19.0N 119.5W MAX WIND 100 KT...GUSTS 120 KT. OUTLOOK VALID 09/1800Z 21.5N 124.5W MAX WIND 75 KT...GUSTS 90 KT. REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 12.5N 104.2W NEXT ADVISORY AT 05/0300Z $$ FORECASTER D. ZELINSKY

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0300 PM CDT Mon Sep 04 2023 Valid 042000Z - 051200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTHERN PLAINS/NORTHERN AND CENTRAL HIGH PLAINS... ...SUMMARY... Isolated severe wind gusts and large hail remain possible over parts of the northern Plains this afternoon and evening, particularly from parts of eastern Wyoming to the Dakotas. ...Discussion... Little change appears necessary to the ongoing outlook at this time, as the convective scenario across the U.S. continues to largely evolve as expected. The primary change has been to extend severe risk southward across more of the central High Plains region. Here, scant low-level moisture and limited CAPE, but a dry sub-cloud layer may support gusty/isolated damaging wind gusts where storms are currently developing. ..Goss.. 09/04/2023 .PREV DISCUSSION... /ISSUED 1141 AM CDT Mon Sep 04 2023/ ...Northern Plains... An upper trough over the Intermountain West/north-central Rockies will continue northeastward toward the Dakotas, with thunderstorms expected to increase near/behind an advancing cold front this afternoon, initially across interior/eastern portions of Wyoming and far southeast Montana. Strengthening winds aloft, steep lapse rates, and modest overall buoyancy will support high-based storms capable of large hail and strong wind gusts. Storms will likely further increase, aggregate, and grow upscale into northeast Wyoming/western South Dakota and eventually North Dakota this evening, with the potential for severe-caliber wind gusts expected to steadily increase accordingly. This also includes some potential for significant wind gusts (65+ kt). ...Ozarks/Mid-South... Widely scattered to scattered, multicellular thunderstorms are expected to increase across the region this afternoon with the potential for localized wind damage, and possibly some sporadic hail near severe limits. This will be as the upper low transitions northeastward toward the region and interfaces with a moderately to strongly unstable boundary layer, with moderately strong winds aloft (25-30 kt at 500 mb? likely contributing to some semi-sustained multicells. Any such severe risk should diminish by around sunset. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0300 PM CDT Mon Sep 04 2023 Valid 042000Z - 051200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTHERN PLAINS/NORTHERN AND CENTRAL HIGH PLAINS... ...SUMMARY... Isolated severe wind gusts and large hail remain possible over parts of the northern Plains this afternoon and evening, particularly from parts of eastern Wyoming to the Dakotas. ...Discussion... Little change appears necessary to the ongoing outlook at this time, as the convective scenario across the U.S. continues to largely evolve as expected. The primary change has been to extend severe risk southward across more of the central High Plains region. Here, scant low-level moisture and limited CAPE, but a dry sub-cloud layer may support gusty/isolated damaging wind gusts where storms are currently developing. ..Goss.. 09/04/2023 .PREV DISCUSSION... /ISSUED 1141 AM CDT Mon Sep 04 2023/ ...Northern Plains... An upper trough over the Intermountain West/north-central Rockies will continue northeastward toward the Dakotas, with thunderstorms expected to increase near/behind an advancing cold front this afternoon, initially across interior/eastern portions of Wyoming and far southeast Montana. Strengthening winds aloft, steep lapse rates, and modest overall buoyancy will support high-based storms capable of large hail and strong wind gusts. Storms will likely further increase, aggregate, and grow upscale into northeast Wyoming/western South Dakota and eventually North Dakota this evening, with the potential for severe-caliber wind gusts expected to steadily increase accordingly. This also includes some potential for significant wind gusts (65+ kt). ...Ozarks/Mid-South... Widely scattered to scattered, multicellular thunderstorms are expected to increase across the region this afternoon with the potential for localized wind damage, and possibly some sporadic hail near severe limits. This will be as the upper low transitions northeastward toward the region and interfaces with a moderately to strongly unstable boundary layer, with moderately strong winds aloft (25-30 kt at 500 mb? likely contributing to some semi-sustained multicells. Any such severe risk should diminish by around sunset. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0300 PM CDT Mon Sep 04 2023 Valid 042000Z - 051200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTHERN PLAINS/NORTHERN AND CENTRAL HIGH PLAINS... ...SUMMARY... Isolated severe wind gusts and large hail remain possible over parts of the northern Plains this afternoon and evening, particularly from parts of eastern Wyoming to the Dakotas. ...Discussion... Little change appears necessary to the ongoing outlook at this time, as the convective scenario across the U.S. continues to largely evolve as expected. The primary change has been to extend severe risk southward across more of the central High Plains region. Here, scant low-level moisture and limited CAPE, but a dry sub-cloud layer may support gusty/isolated damaging wind gusts where storms are currently developing. ..Goss.. 09/04/2023 .PREV DISCUSSION... /ISSUED 1141 AM CDT Mon Sep 04 2023/ ...Northern Plains... An upper trough over the Intermountain West/north-central Rockies will continue northeastward toward the Dakotas, with thunderstorms expected to increase near/behind an advancing cold front this afternoon, initially across interior/eastern portions of Wyoming and far southeast Montana. Strengthening winds aloft, steep lapse rates, and modest overall buoyancy will support high-based storms capable of large hail and strong wind gusts. Storms will likely further increase, aggregate, and grow upscale into northeast Wyoming/western South Dakota and eventually North Dakota this evening, with the potential for severe-caliber wind gusts expected to steadily increase accordingly. This also includes some potential for significant wind gusts (65+ kt). ...Ozarks/Mid-South... Widely scattered to scattered, multicellular thunderstorms are expected to increase across the region this afternoon with the potential for localized wind damage, and possibly some sporadic hail near severe limits. This will be as the upper low transitions northeastward toward the region and interfaces with a moderately to strongly unstable boundary layer, with moderately strong winds aloft (25-30 kt at 500 mb? likely contributing to some semi-sustained multicells. Any such severe risk should diminish by around sunset. Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0216 PM CDT Mon Sep 04 2023 Valid 061200Z - 121200Z The potential for critical fire weather conditions appears low through the extended period. Long-range guidance continues to show a building upper ridge over northern Mexico and into the Southwest region through the mid/late week period, which will maintain warm and dry conditions from west TX to the Four Corners. There is a signal in ensemble guidance for 15-25 mph winds across the greater Four Corners region D3/Wednesday into D4/Thursday as a shortwave trough passes through the Pacific Northwest and augments the regional pressure gradient. However, recent reports and ERC analyses indicate fuels are not currently receptive and may require multiple days of drying before supporting a fire weather concern. Across the Plains where fuels are currently dry, ensemble clusters show a reasonably good signal for increasing rain chances across the Plains starting D5/Friday into early next week. While some areas may remain dry, the potential for wetting rain over the broader region limits confidence in the overall fire weather threat at this range. ..Moore.. 09/04/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0216 PM CDT Mon Sep 04 2023 Valid 061200Z - 121200Z The potential for critical fire weather conditions appears low through the extended period. Long-range guidance continues to show a building upper ridge over northern Mexico and into the Southwest region through the mid/late week period, which will maintain warm and dry conditions from west TX to the Four Corners. There is a signal in ensemble guidance for 15-25 mph winds across the greater Four Corners region D3/Wednesday into D4/Thursday as a shortwave trough passes through the Pacific Northwest and augments the regional pressure gradient. However, recent reports and ERC analyses indicate fuels are not currently receptive and may require multiple days of drying before supporting a fire weather concern. Across the Plains where fuels are currently dry, ensemble clusters show a reasonably good signal for increasing rain chances across the Plains starting D5/Friday into early next week. While some areas may remain dry, the potential for wetting rain over the broader region limits confidence in the overall fire weather threat at this range. ..Moore.. 09/04/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0216 PM CDT Mon Sep 04 2023 Valid 061200Z - 121200Z The potential for critical fire weather conditions appears low through the extended period. Long-range guidance continues to show a building upper ridge over northern Mexico and into the Southwest region through the mid/late week period, which will maintain warm and dry conditions from west TX to the Four Corners. There is a signal in ensemble guidance for 15-25 mph winds across the greater Four Corners region D3/Wednesday into D4/Thursday as a shortwave trough passes through the Pacific Northwest and augments the regional pressure gradient. However, recent reports and ERC analyses indicate fuels are not currently receptive and may require multiple days of drying before supporting a fire weather concern. Across the Plains where fuels are currently dry, ensemble clusters show a reasonably good signal for increasing rain chances across the Plains starting D5/Friday into early next week. While some areas may remain dry, the potential for wetting rain over the broader region limits confidence in the overall fire weather threat at this range. ..Moore.. 09/04/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more