Aggregator

WW 643 SEVERE TSTM KS 132205Z - 140400Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 643 NWS Storm Prediction Center Norman OK 505 PM CDT Sun Aug 13 2023 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Central into southeast Kansas * Effective this Sunday afternoon and evening from 505 PM until 1100 PM CDT. * Primary threats include... Scattered damaging wind gusts to 70 mph likely Scattered large hail events to 1.5 inches in diameter likely SUMMARY...Scattered supercell development is expected this afternoon and storms will spread east-southeastward through late evening with an attendant threat for large hail up to 1.5 inches in diameter. Some clustering of storms is also expected, which will favor the potential for severe outflow gusts of 60-70 mph. The severe thunderstorm watch area is approximately along and 65 statute miles north and south of a line from 55 miles northwest of Medicine Lodge KS to 20 miles north northeast of Chanute KS. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU3). 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 640...WW 641...WW 642... AVIATION...A few severe thunderstorms with hail surface and aloft to 1.5 inches. Extreme turbulence and surface wind gusts to 60 knots. A few cumulonimbi with maximum tops to 550. Mean storm motion vector 29025. ...Thompson Read more

MD 1985 CONCERNING SEVERE THUNDERSTORM WATCH 641... FOR PORTIONS OF NORTHERN AND CENTRAL AL...INTO SOUTHERN TN AND NORTHWEST GA
Mesoscale Discussion 1985 NWS Storm Prediction Center Norman OK 0449 PM CDT Sun Aug 13 2023 Areas affected...portions of northern and central AL...into southern TN and northwest GA Concerning...Severe Thunderstorm Watch 641... Valid 132149Z - 132245Z The severe weather threat for Severe Thunderstorm Watch 641 continues. SUMMARY...The risk for damaging gusts should continue across WW641 this afternoon. Storms may continue farther south and east where a new weather watch is possible, but uncertain. DISCUSSION...As of 2135 UTC, regional radar analysis showed a linear cluster of storms ongoing across portions of the TN Valley. Over the last couple of hours, several reports of damaging gusts have been received with gusty outflow winds from these storms. The environment ahead of these storms remains strongly unstable, with 3000+ J/kg of MLCAPE, but only weak vertical shear. So far storms have been semi-organized along a propagating cold pool. Weak shear balance and the favorable buoyancy should allow for strong updrafts and damaging gust potential to continue across north-central AL and portions of southern TN over the next couple of hours. Farther south, uncertainty on the severe risk is higher as additional storms have resulted in some overturning of the air mass west of Atlanta into central AL. Outflow temperatures have dropped into the upper 70s F, which may limit the potential for stronger updrafts as the cluster moves south/southeast later this evening. If storms are able to retain strength as they move into the cooler air, as suggested by several HRRR runs, damaging gusts would be possible into parts of central AL and western GA. Convective trends will be monitored but it is unclear if a new weather watch is needed farther south. ..Lyons/Thompson.. 08/13/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...MRX...FFC...OHX...BMX...HUN...MEG... LAT...LON 35428635 36058538 36028466 35718457 35338456 34988457 34598462 34098474 33598494 33408505 33258532 33198566 33258614 33328649 33458710 33658756 33798782 33958811 34158819 34448816 34708786 34958738 35208676 35428635 Read more

WW 0642 Status Updates
STATUS FOR WATCH 0642 HAS NOT BEEN ISSUED YET Read more

WW 642 SEVERE TSTM OK TX 132145Z - 140400Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 642 NWS Storm Prediction Center Norman OK 445 PM CDT Sun Aug 13 2023 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Western and northern Oklahoma and the eastern Oklahoma Panhandle The eastern Texas Panhandle * Effective this Sunday afternoon and evening from 445 PM until 1100 PM CDT. * Primary threats include... Scattered damaging wind gusts to 70 mph likely Scattered large hail events to 1.5 inches in diameter possible SUMMARY...Clusters of storms will continue to form in the Texas Panhandle and spread into western and northern Oklahoma through late evening. The storm environment favors occasional severe outflow winds of 60-70 mph and isolated large hail of 1-1.5 inches in diameter. The severe thunderstorm watch area is approximately along and 85 statute miles east and west of a line from 20 miles northeast of Alva OK to 70 miles west southwest of Clinton OK. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU2). 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 640...WW 641... AVIATION...A few severe thunderstorms with hail surface and aloft to 1.5 inches. Extreme turbulence and surface wind gusts to 60 knots. A few cumulonimbi with maximum tops to 550. Mean storm motion vector 26025. ...Thompson Read more

WW 0641 Status Updates
STATUS REPORT ON WW 641 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 25 NE UOX TO 25 N HSV TO 25 ESE BWG. ..WEINMAN..08/13/23 ATTN...WFO...HUN...MEG...OHX... STATUS REPORT FOR WS 641 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ALC033-049-059-071-077-079-083-089-095-103-132240- AL . ALABAMA COUNTIES INCLUDED ARE COLBERT DEKALB FRANKLIN JACKSON LAUDERDALE LAWRENCE LIMESTONE MADISON MARSHALL MORGAN MSC117-141-132240- MS . MISSISSIPPI COUNTIES INCLUDED ARE PRENTISS TISHOMINGO TNC003-015-031-041-051-061-103-111-127-149-159-165-169-177-189- 132240- TN . TENNESSEE COUNTIES INCLUDED ARE Read more

WW 641 SEVERE TSTM AL MS TN 131835Z - 140100Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 641 NWS Storm Prediction Center Norman OK 135 PM CDT Sun Aug 13 2023 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Northern Alabama Northeast Mississippi Middle Tennessee * Effective this Sunday afternoon and evening from 135 PM until 800 PM CDT. * Primary threats include... Scattered damaging wind gusts to 60 mph possible SUMMARY...Storms are expected to continue to intensify across the region with a linear cluster evolving, with damaging winds as the primary severe hazard. The severe thunderstorm watch area is approximately along and 80 statute miles north and south of a line from 60 miles northwest of Muscle Shoals AL to 60 miles southeast of Nashville TN. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU1). 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 640... AVIATION...A few severe thunderstorms with hail surface and aloft to 1 inch. Extreme turbulence and surface wind gusts to 50 knots. A few cumulonimbi with maximum tops to 550. Mean storm motion vector 28025. ...Guyer Read more

WW 0640 Status Updates
STATUS REPORT ON WW 640 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..WEINMAN..08/13/23 ATTN...WFO...GYX...CAR... STATUS REPORT FOR WS 640 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS MEC001-003-005-007-009-011-013-015-017-019-021-023-025-027-031- 132240- ME . MAINE COUNTIES INCLUDED ARE ANDROSCOGGIN AROOSTOOK CUMBERLAND FRANKLIN HANCOCK KENNEBEC KNOX LINCOLN OXFORD PENOBSCOT PISCATAQUIS SAGADAHOC SOMERSET WALDO YORK NHC001-003-015-017-132240- NH . NEW HAMPSHIRE COUNTIES INCLUDED ARE BELKNAP CARROLL ROCKINGHAM STRAFFORD 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 640 SEVERE TSTM ME NH 131750Z - 140100Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 640 NWS Storm Prediction Center Norman OK 150 PM EDT Sun Aug 13 2023 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Maine Eastern New Hampshire * Effective this Sunday afternoon and evening from 150 PM until 900 PM EDT. * Primary threats include... Scattered damaging wind gusts to 65 mph possible Scattered large hail events to 1.5 inches in diameter possible SUMMARY...Scattered thunderstorms are forecast to intensify this afternoon with the stronger storms being capable of large hail and damaging gusts. This activity will gradually move from west to east across the watch area through the afternoon into the early evening. The severe thunderstorm watch area is approximately along and 70 statute miles east and west of a line from 30 miles northwest of Caribou ME to 10 miles southeast of Portsmouth NH. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU0). 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 55 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 26025. ...Smith Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0352 PM CDT Sun Aug 13 2023 Valid 151200Z - 211200Z The extended period forecast remains challenging with upper low/Rex block pattern in the eastern Pacific. Model guidance continues to vary with the progression/evolution of this feature in the near term. This variance increases with time. At the surface, a cold front will move through the Southern Plains early in the week. Other cold fronts will make progress into the Plains mid/late week. ...Northwest... Thunderstorm chances will increases into southern Oregon starting on Tuesday. Another push of mid-level moisture will begin on Thursday and renew thunderstorm potential. Activity will move northward each day into the weekend and early next week. There is some uncertainty as to when thunderstorm activity will begin to decrease. The GFS is more bullish on moving a shortwave trough across the Canadian border and pushing moisture out of the region at least temporarily. PWAT values will be a bit on the marginal side for dry thunderstorms in addition to storm motions being relatively slow between the upper low and the stronger mid-level winds to the north. As storms move northward, though, some drier storms would be possible along the leading edge of the moisture. Given all the complicating factors, confidence in placing dry thunderstorm highlights is low. Potential for locally dry and windy conditions is evident within the Cascade gaps/Columbia Gorge as temperatures increase into the Columbia Basin. The signal for more broadly critical fire weather is currently on Thursday when mid-level winds will be stronger and a surface low will deepen to the northeast. This could continue on Friday afternoon as well, but model differences in the upper/low-level patterns decrease confidence. ...Northern California... Thunderstorm activity is possible each afternoon from Tuesday into potentially the weekend. Storm motions will initially be slow and PWAT values will be somewhat high. Lighting outside of storm cores would remain a concern. The upper low is forecast to remain off the central California coast into the weekend and even intensify. As this occurs, drier air may get pulled northward. Thunderstorm potential will gradually decrease south to north with time. A few drier storms may occur later in the week, but with storm potential every afternoon in the same areas, fuels may be affected by that time. ...Montana... With an upper-level trough moving through the northern Plains on Tuesday/Wednesday, some dry and windy conditions are possible for parts of Montana. Some downslope enhancement is possible in the lee of the Rockies on Tuesday. Spatial extent of the fire weather threat appears very limited given the modest surface gradient and upper-level winds. Greater potential for critical fire weather is evident on Thursday as mid-level winds will be somewhat stronger across the terrain and a deeper surface low is expected to the north. Some potential could also exist into Friday, but the evolution of the upper-level/surface pattern is a bit too uncertain for highlights. ...Texas... Cooler, but relatively dry, northerly winds will be present behind the cold front perhaps into Tuesday/Wednesday of next week. There is low-end potential for a pocket of dry and windy conditions to develop in parts of East Texas on the western flank of an upper trough on Tuesday. Heat will return by late week. With a surface trough remaining in the region into the weekend, some concerns for elevated fire weather may develop in portions of western/central Texas. Furthermore, isolated thunderstorms are possible during the afternoons with the intense heat and may pose some concern for lightning ignitions given the dry fuels. ..Wendt.. 08/13/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

5-Day Uncertainty Track last updated Sun, 13 Aug 2023 20:39:07 GMT


Wind Speed Probabilities last updated Sun, 13 Aug 2023 21:22:55 GMT

Issued at 200 PM PDT Sun Aug 13 2023 669 WTPZ42 KNHC 132037 TCDEP2 Hurricane Fernanda Discussion Number 5 NWS National Hurricane Center Miami FL EP072023 200 PM PDT Sun Aug 13 2023 Satellite imagery indicates that small Fernanda has been strengthening rapidly today. A faint eye has become apparent on visible satellite imagery, and outer banding features are becoming better defined. Since the presence of a visible eye is usually a good indicator that a tropical cyclone has become a hurricane, the system is being upgraded on this advisory. This intensity is also in agreement with a Dvorak classification from SAB. The upper-level outflow pattern has also become more symmetric over the circulation. Fernanda continues moving west-northwestward at a slightly slower pace with an estimated motion of 285/8 kt. The mid-level ridge to the north of the tropical cyclone is currently rather weak due to the presence of a cutoff low near the California coast. Over the next few days, the ridge to the north of Fernanda is forecast to strengthen as the influence of the cutoff low lessens. As a result, the system should move somewhat faster to the west-northwest during the next 72 hours or so while turning westward later in the forecast period. The official track forecast remains very close to the previous one and is also very similar to the dynamical model consensus aid TVCE. The hurricane should continue to pass over SSTs of around 29 deg C for the next day or two while remaining in a very low vertical shear environment. The rapid intensification (RI) indices such as SHIPS, RII, and DTOPS continue to show a good chance of RI continuing over the next day or so. Thus, the official forecast will again call for RI over the next 24 hours. However, in about 48 hours, drier mid-level air should halt the strengthening process. The numerical guidance is in good agreement that Fernanda will steadily weaken in 2-5 days, and this is reflected in the NHC intensity forecast, which is fairly close to the latest corrected consensus prediction. FORECAST POSITIONS AND MAX WINDS INIT 13/2100Z 15.5N 116.5W 65 KT 75 MPH 12H 14/0600Z 15.8N 117.6W 80 KT 90 MPH 24H 14/1800Z 16.2N 119.0W 95 KT 110 MPH 36H 15/0600Z 16.7N 120.6W 95 KT 110 MPH 48H 15/1800Z 17.3N 122.5W 85 KT 100 MPH 60H 16/0600Z 17.5N 124.9W 75 KT 85 MPH 72H 16/1800Z 17.7N 127.2W 65 KT 75 MPH 96H 17/1800Z 18.0N 132.5W 45 KT 50 MPH 120H 18/1800Z 18.0N 138.0W 35 KT 40 MPH $$ Forecaster Pasch

Issued at 2100 UTC SUN AUG 13 2023 000 FOPZ12 KNHC 132037 PWSEP2 HURRICANE FERNANDA WIND SPEED PROBABILITIES NUMBER 5 NWS NATIONAL HURRICANE CENTER MIAMI FL EP072023 2100 UTC SUN AUG 13 2023 AT 2100Z THE CENTER OF HURRICANE FERNANDA WAS LOCATED NEAR LATITUDE 15.5 NORTH...LONGITUDE 116.5 WEST WITH MAXIMUM SUSTAINED WINDS NEAR 65 KTS...75 MPH...120 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 SUN 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 SUN 06Z MON 18Z MON 06Z TUE 18Z TUE 18Z WED 18Z THU PERIODS TO TO TO TO TO TO TO 06Z MON 18Z MON 06Z TUE 18Z TUE 18Z WED 18Z THU 18Z FRI FORECAST HOUR (12) (24) (36) (48) (72) (96) (120) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - LOCATION KT 15N 120W 34 X 17(17) 21(38) 3(41) X(41) X(41) X(41) 15N 120W 50 X 2( 2) 5( 7) X( 7) X( 7) X( 7) X( 7) 15N 120W 64 X 1( 1) 1( 2) X( 2) X( 2) X( 2) X( 2) 20N 120W 34 X 1( 1) 3( 4) 5( 9) 2(11) X(11) X(11) 15N 125W 34 X X( X) 2( 2) 4( 6) 12(18) 1(19) X(19) 20N 125W 34 X X( X) 1( 1) 5( 6) 20(26) 1(27) X(27) 20N 125W 50 X X( X) X( X) 1( 1) 4( 5) X( 5) X( 5) 20N 125W 64 X X( X) X( X) X( X) 1( 1) X( 1) X( 1) 15N 130W 34 X X( X) X( X) X( X) 4( 4) 7(11) X(11) 20N 130W 34 X X( X) X( X) X( X) 7( 7) 17(24) X(24) 20N 130W 50 X X( X) X( X) X( X) X( X) 5( 5) X( 5) 15N 135W 34 X X( X) X( X) X( X) X( X) 2( 2) 2( 4) 20N 135W 34 X X( X) X( X) X( X) X( X) 5( 5) 7(12) $$ FORECASTER PASCH

Issued at 2100 UTC SUN AUG 13 2023 000 WTPZ22 KNHC 132036 TCMEP2 HURRICANE FERNANDA FORECAST/ADVISORY NUMBER 5 NWS NATIONAL HURRICANE CENTER MIAMI FL EP072023 2100 UTC SUN AUG 13 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). HURRICANE CENTER LOCATED NEAR 15.5N 116.5W AT 13/2100Z POSITION ACCURATE WITHIN 15 NM PRESENT MOVEMENT TOWARD THE WEST-NORTHWEST OR 285 DEGREES AT 8 KT ESTIMATED MINIMUM CENTRAL PRESSURE 995 MB MAX SUSTAINED WINDS 65 KT WITH GUSTS TO 80 KT. 64 KT....... 10NE 0SE 0SW 0NW. 50 KT....... 25NE 25SE 0SW 0NW. 34 KT....... 50NE 50SE 20SW 40NW. 12 FT SEAS..120NE 60SE 30SW 60NW. WINDS AND SEAS VARY GREATLY IN EACH QUADRANT. RADII IN NAUTICAL MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT. REPEAT...CENTER LOCATED NEAR 15.5N 116.5W AT 13/2100Z AT 13/1800Z CENTER WAS LOCATED NEAR 15.5N 116.1W FORECAST VALID 14/0600Z 15.8N 117.6W MAX WIND 80 KT...GUSTS 100 KT. 64 KT... 10NE 10SE 0SW 0NW. 50 KT... 30NE 20SE 0SW 20NW. 34 KT... 60NE 60SE 30SW 40NW. FORECAST VALID 14/1800Z 16.2N 119.0W MAX WIND 95 KT...GUSTS 115 KT. 64 KT... 15NE 10SE 10SW 10NW. 50 KT... 30NE 20SE 20SW 30NW. 34 KT... 70NE 50SE 40SW 60NW. FORECAST VALID 15/0600Z 16.7N 120.6W MAX WIND 95 KT...GUSTS 115 KT. 64 KT... 15NE 10SE 10SW 10NW. 50 KT... 30NE 20SE 20SW 30NW. 34 KT... 70NE 50SE 40SW 60NW. FORECAST VALID 15/1800Z 17.3N 122.5W MAX WIND 85 KT...GUSTS 105 KT. 64 KT... 10NE 10SE 10SW 10NW. 50 KT... 30NE 20SE 20SW 30NW. 34 KT... 70NE 50SE 40SW 70NW. FORECAST VALID 16/0600Z 17.5N 124.9W MAX WIND 75 KT...GUSTS 90 KT. 50 KT... 30NE 20SE 20SW 30NW. 34 KT... 70NE 50SE 40SW 60NW. FORECAST VALID 16/1800Z 17.7N 127.2W MAX WIND 65 KT...GUSTS 80 KT. 50 KT... 30NE 20SE 10SW 30NW. 34 KT... 60NE 50SE 30SW 60NW. EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 100 NM ON DAY 4 AND 125 NM ON DAY 5...AND FOR INTENSITY NEAR 15 KT EACH DAY OUTLOOK VALID 17/1800Z 18.0N 132.5W MAX WIND 45 KT...GUSTS 55 KT. OUTLOOK VALID 18/1800Z 18.0N 138.0W MAX WIND 35 KT...GUSTS 45 KT. REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 15.5N 116.5W NEXT ADVISORY AT 14/0300Z $$ FORECASTER PASCH

Issued at 200 PM PDT Sun Aug 13 2023 000 WTPZ32 KNHC 132036 TCPEP2 BULLETIN Hurricane Fernanda Advisory Number 5 NWS National Hurricane Center Miami FL EP072023 200 PM PDT Sun Aug 13 2023 ...FERNANDA RAPIDLY INTENSIFIES INTO A HURRICANE... SUMMARY OF 200 PM PDT...2100 UTC...INFORMATION ---------------------------------------------- LOCATION...15.5N 116.5W ABOUT 670 MI...1075 KM SW OF THE SOUTHERN TIP OF BAJA CALIFORNIA MAXIMUM SUSTAINED WINDS...75 MPH...120 KM/H PRESENT MOVEMENT...WNW OR 285 DEGREES AT 9 MPH...15 KM/H MINIMUM CENTRAL PRESSURE...995 MB...29.39 INCHES WATCHES AND WARNINGS -------------------- There are no coastal watches or warnings in effect. DISCUSSION AND OUTLOOK ---------------------- At 200 PM PDT (2100 UTC), the center of Hurricane Fernanda was located near latitude 15.5 North, longitude 116.5 West. Fernanda is moving toward the west-northwest near 9 mph (15 km/h), and this general motion with some increase in forward speed is expected over the next few days. Maximum sustained winds have increased to near 75 mph (120 km/h) with higher gusts. Additional rapid strengthening is forecast during the next day or so. Fernanda is a small tropical cyclone. Hurricane-force winds extend outward up to 10 miles (20 km) from the center and tropical-storm-force winds extend outward up to 60 miles (95 km). The estimated minimum central pressure is 995 mb (29.39 inches). HAZARDS AFFECTING LAND ---------------------- None NEXT ADVISORY ------------- Next complete advisory at 800 PM PDT. $$ Forecaster Pasch

...FERNANDA RAPIDLY INTENSIFIES INTO A HURRICANE... As of 2:00 PM PDT Sun Aug 13 the center of Fernanda was located near 15.5, -116.5 with movement WNW at 9 mph. The minimum central pressure was 995 mb with maximum sustained winds of about 75 mph.

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0245 PM CDT Sun Aug 13 2023 Valid 132000Z - 141200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS THE OZARKS... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE SOUTH-CENTRAL PLAINS TO THE TENNESSEE VALLEY...AND PORTIONS OF NEW ENGLAND... ...SUMMARY... Severe thunderstorm wind gusts, large hail and a tornado threat are expected late this afternoon into tonight, especially across the south-central Plains and Ozarks. Other severe thunderstorms will persist into early evening across New England. ...20z Update... The overall forecast philosophy is unchanged from the 1630z outlook (see previous discussion below). The only minor change in severe probabilities is across parts of southeast MN into extreme southwest WI and eastern IA where the Marginal (level 1 of 5) risk has been expanded. This expansion is related to severe potential late tonight into early Monday morning associated with convection beneath the cold core of the upper shortwave trough and in the vicinity of the surface low. Damaging wind potential will continue this afternoon across the TN Valley as an ongoing MCS spreads east/southeast. Ref Severe Thunderstorm Watch 641 and forthcoming MCDs for short term severe trends. Additional isolated severe storms will continue the next several hours across parts of Maine and vicinity where Severe Thunderstorm Watch 640 is in effect until early 01z. Severe potential is expected to increase from late afternoon into this evening across the south-central Plains toward southern MO. See MCD 1982 for short term severe potential across parts of KS. Early day convection has modified and stabilized the low-levels across MO (per mesoanalysis and 18z SGF RAOB) and will likely delay convection until this evening as the airmass recovers and a low-level jet increases. Convection will then spread east/southeast from KS/OK along residual outflow/differential heating corridor posing an all-hazards risk. ..Leitman.. 08/13/2023 .PREV DISCUSSION... /ISSUED 1154 AM CDT Sun Aug 13 2023/ ...South-Central Plains/Ozarks/Mid-South... The Lower Missouri Valley/Ozarks continue to be considerably influenced by persistent convection/MCVs at midday, with only modestly broken cloud cover across much of the warm sector ahead of the primary front. But a gradual trend of thinning/less prevalent cloud cover is noted from the west across the south-central Plains, which should allow for moderate to locally strong destabilization into/around peak heating. Deep convection is expected to develop in multiple zones by late afternoon/sunset, including across the middle Missouri Valley/eastern South Dakota vicinity near the surface low, and otherwise near the south/southeastward-moving front across southeast Nebraska and portions of Kansas, as well as across the Oklahoma/Texas Panhandles and western/northern Oklahoma. Some of this convection, as it evolves across eastern Kansas toward the Ozarks, will interface with residual differential heating and a weak residual boundary or two. Seasonally strong winds aloft will influence supercell-favorable hodographs, with large hail initially the primary hazard. Several clusters of storms should evolve by early evening, potentially including northern Oklahoma/southeast Kansas into the Ozarks, where a somewhat higher-probability for wind damage, along with some tornado potential, is expected to exist this evening, and possibly linger into the overnight. ...Tennessee Valley/southern Appalachians... On the northern fringe of the upper ridge and stronger capping aloft, a remnant cluster/MCV across far southeast Missouri/northeast Arkansas at midday will likely influence additional downstream convective development and intensification this afternoon within a moderate to strongly unstable environment. Westerlies remain a bit stronger than typical mid-August scenarios, and this should influence the persistence and organization of the storms, with some semi-organized multicellular clusters possible. Wind damage will be the primary hazard regionally. For additional details, see Mesoscale Discussion 1981. ...New England... A Slight Risk has been introduced for expectations of a somewhat greater severe-weather potential today. Isolated/widely scattered thunderstorms are expected to further develop through early afternoon along and ahead of the surface cold front. A moderately unstable environment and with deep-layer shear around 30-35 kt will support some organized multicells capable of severe hail and locally damaging wind gusts. For additional details, see Mesoscale Discussion 1980. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0214 PM CDT Sun Aug 13 2023 Valid 141200Z - 151200Z The forecast generally remains on track. Breezy conditions are expected behind the cold front in Texas. However, RH will generally remain above critical thresholds. Some locally elevated conditions are certainly possible. Dry thunderstorm activity remains possible overnight in northern California. Coverage still appears to be very low at this time. ..Wendt.. 08/13/2023 .PREV DISCUSSION... /ISSUED 0152 AM CDT Sun Aug 13 2023/ ...Synopsis... High pressure over the Northwest is forecast to intensify as it moves inland over portions of WA and OR. Gusty north winds and hot surface conditions are expected to support local fire-weather concerns. A weak mid-level low and monsoon moisture will also lift north across CA, supporting the potential for dry thunderstorms late D2/Monday into early D3/Tuesday. ...Northwest... As the upper ridge continues to intensify and move inland, northerly flow is forecast to increase across portions of southwest WA and central OR. Bolstered by a thermally induced surface trough, surface gusts of 15-25 mph gusts are expected within the higher terrain. Poor overnight humidity recoveries from the dry northerly flow and hot afternoon temperatures will support surface RH values below 35%. A few hours of elevated fire-weather conditions appear likely given critically dry fuels. ...Northern CA... Monsoon moisture associated with the weak upper low is forecast to move into portions of northern CA late D2/Monday into early D3/Tuesday. Model soundings show PWAT values of 0.7 to 0.8 inches atop dry low levels. Weak buoyancy aloft may support isolated thunderstorms into the overnight hours, with the potential for lightning ignitions given the dry low-level air mass. However, significant uncertainty remains on storm coverage and the exact placement with relatively modest forcing for ascent. IsoDryT highlight will be withheld for now, but may be needed should greater confidence in dry storm coverage develop in subsequent forecasts. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

000
ABPZ20 KNHC 131736
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 AM PDT Sun Aug 13 2023

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

Active Systems:
The National Hurricane Center is issuing advisories on Tropical
Storm Fernanda, located several hundred miles southwest of the
southern tip of the Baja California peninsula.

Western East Pacific (EP99):
Showers and thunderstorms are becoming better organized in
association with an area of low pressure located about 1400 miles
east-southeast of the Hawaiian Islands. Environmental conditions
appear conducive for continued development, and a tropical
depression is likely to form during the next day or so as it moves
westward or west-northwestward at 10 to 15 mph. The system is
forecast to cross into the Central Pacific basin late tonight.
* Formation chance through 48 hours...high...90 percent.
* Formation chance through 7 days...high...90 percent.

Off the Coast of Southern Mexico:
A tropical wave continues to produce a large area of disorganized
showers and thunderstorms over the far eastern portion of the east
Pacific. Environmental conditions appear conducive for development
during the next several days, and a tropical depression is expected
to form by midweek while the system moves west-northwestward,
roughly parallel to the coast of southern and southwestern Mexico.
* Formation chance through 48 hours...low...30 percent.
* Formation chance through 7 days...high...90 percent.

$$
Forecaster Reinhart

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1232 PM CDT Sun Aug 13 2023 Valid 141200Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN KENTUCKY AND TENNESSEE INTO THE MID-ATLANTIC STATES... ...SUMMARY... Severe thunderstorms are possible Monday afternoon and evening across portions of Kentucky and Tennessee, extending north and east to the Mid-Atlantic States. ...Synopsis... A mid/upper shortwave trough oriented from the Upper Midwest to the southern Plains will develop eastward, extending from the eastern Great Lakes to the Mid-South by Tuesday morning. This will bring an belt of enhanced deep-layer southwesterly flow stretching across the Ohio Valley vicinity to the Mid-Atlantic and southern New England. At the surface, low pressure in the vicinity of eastern IA at the beginning of the period will track east to Lake Erie by 12z Tuesday. A cold front attendant to the low will shift east/southeast, extending from eastern IL to northern TX by late afternoon. This front will continue east/southeast through the overnight hours, becoming aligned along the central/southern Appalachians to south TX. A pre-frontal trough is forecast ahead of the main cold front and will become the main focus for strong/severe thunderstorm development (along with any outflow/MCVs associated with prior day's or ongoing morning convection) from KY/TN eastward. Another band of strong/severe thunderstorms attendant to the synoptic cold front and surface low are possible across parts of northern IL/far southern WI eastward across southern Lower MI/IN and northern/western OH from Monday morning into the early evening. ...OH/TN Valley vicinity to the Mid-Atlantic... Convection will likely be ongoing Monday morning across the Lower OH Valley in association with a lead shortwave impulse ahead of the main mid/upper trough. This cluster/MCS will spread east/northeast across WV/VA and southern PA through the afternoon and over the Delaware Valley during the evening. Outflow from morning convection may sag southward into Middle/eastern TN and become a focus for additional diurnal convection from the Cumberland Plateau eastward into the Carolinas. A warm front will be draped across northern MD into southern NJ. To the south of the warm front, southwesterly low-level flow will maintain upper 60s to low 70s F dewpoints, contributing to 1500-2500 J/kg MLCAPE (locally higher possible across eastern KY into TN). Moderate to strong vertical shear and steep low-level lapse rates will support a damaging wind risk from eastern KY into WV and the Mid-Atlantic. Where low-level flow is expected to remain more southeasterly in the vicinity warm front in the Delmarva vicinity, a locally higher tornado risk is possible. Further south across TN into the Carolinas, large-scale ascent will be somewhat weaker. However, moderate to strong instability, steep low-level lapse rates and modest vertical shear will support a risk for damaging winds. The greatest concentration of severe gusts is expected across parts of Middle into eastern TN. ...Lake Michigan vicinity into western OH... Beneath the core of the main upper trough and surface low, a tongue of boundary-layer moisture (dewpoints in the 60s) will arc westward from eastern OH to far eastern IA and southern WI/MI. This will result in a narrow corridor of MLCAPE up to 1000 J/kg. Within this cold core setup, enhanced low-level shear along a warm front will lead to enlarged low-level hodographs, becoming elongated above 2 km. This could support a couple of brief tornadoes and/or strong gusts from stronger cells from late morning into the afternoon. If any organized strong/deeper updrafts can be maintained, isolated hail to near 1 inch also will be possible. ..Leitman.. 08/13/2023 Read more