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SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0157 PM CDT Sun Aug 20 2023 Valid 211200Z - 221200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF CENTRAL TEXAS... The previous forecast (see below) remains generally on track. The two main changes in this outlook were to add Elevated highlights to eastern Wyoming and expand the Elevated in Texas eastward to central Louisiana. In Wyoming, 15-25 mph sustained southwesterly surface winds should overlap with 15-20 percent RH during the late morning to late afternoon hours. Grass-based fuels in this area have been exposed to multiple days of relatively dry conditions and have not received appreciable rainfall for at least the last 1-2 weeks. These fuels have become at least marginally receptive to wildfire spread, necessitating the introduction of Elevated highlights. Meanwhile, prolonged dry conditions have materialized across portions of the mid-south, resulting in the curing of fuels in this region. Elevated highlights have been extended into Louisiana to account for the increasingly receptive fuels, RH dipping below 30 percent, and at least locally gusty conditions expected. ..Squitieri.. 08/20/2023 .PREV DISCUSSION... /ISSUED 0218 AM CDT Sun Aug 20 2023/ ...Synopsis... A midlevel anticyclone over the central Plains will shift slightly northeastward on Day 2/Monday, yielding a slight increase in deep-layer easterlies across much of TX. At the same time, a modest increase in the surface pressure gradient is expected along the northwestern periphery of a weather disturbance moving across the Gulf of Mexico. ...Central and north TX... An anomalously warm/dry air mass will remain in place across much of central and north TX -- where 100+ deg afternoon temperatures and around 20 percent RH are expected. Deep boundary-layer mixing into the enhanced easterly low/mid-level flow, coupled with the tightening pressure gradient, will support 15-20 mph sustained east-southeasterly surface winds and locally higher gusts. Given exceptionally dry fuels over the area (95th+ percentile ERCs), critical fire-weather conditions are expected. ...Central High Plains... Similar to Day 1/Sunday, efficient diurnal heating/mixing will yield 15-20 percent minimum RH. At the same time, 15-20 mph sustained southerly surface winds are expected owing to a tightening pressure gradient, with gusts upwards of 30 mph possible. This dry/breezy combination will favor another day of elevated to spotty critical fire-weather conditions. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

541
ABNT20 KNHC 201804 CCA
TWOAT

Tropical Weather Outlook... Corrected
NWS National Hurricane Center Miami FL
200 PM EDT Sun Aug 20 2023

Corrected Emily's location relative to the Cabo Verde Islands

For the North Atlantic...Caribbean Sea and the Gulf of Mexico:

Active Systems:
The National Hurricane Center is issuing advisories on Tropical
Depression Six, located several hundred miles east of the northern
Leeward Islands and on newly formed Tropical Storm Emily, located
about 1000 miles west-northwest of the Cabo Verde Islands.

Eastern Caribbean (AL90):
Showers and thunderstorms continue to show signs of organization in
association with an area of low pressure over the eastern Caribbean
Sea. In addition, visible satellite imagery shows evidence that a
well-defined center is developing, and earlier satellite wind data
indicated the system was producing winds of 35-40 mph. If these
trends continue, a tropical depression or storm could form as soon
as later this afternoon. A NOAA Hurricane Reconnaissance mission is
currently en route to investigate the system this afternoon. The
system is forecast to move westward to west-northwestward at 10 to
15 mph over the eastern and central Caribbean, before turning
northward and potentially affecting the Dominican Republic and Haiti
on Tuesday or Wednesday, where tropical storm watches could become
necessary later this afternoon. Regardless of development, heavy
rainfall is possible over portions of the Lesser Antilles during the
next couple of days. Interests in the eastern and central Caribbean
should monitor the progress of this system.
* Formation chance through 48 hours...high...90 percent.
* Formation chance through 7 days...high...90 percent.

Western Gulf of Mexico (AL91):
Showers and thunderstorms have increased this afternoon in
association with an area of disturbed weather located in the eastern
Gulf of Mexico. Additional development of this system is possible as
it moves westward at about 15 to 20 mph, and a tropical depression
could form as it approaches the western Gulf of Mexico coastline by
Tuesday.
* Formation chance through 48 hours...medium...50 percent.
* Formation chance through 7 days...medium...60 percent.

Eastern Tropical Atlantic:
A large area of disorganized showers and thunderstorms over the far
eastern tropical Atlantic is associated with a tropical wave
centered just southeast of the Cabo Verde Islands. Environmental
conditions appear conducive for gradual development of this system,
and a tropical depression could form later this week while it moves
west-northwestward across the eastern tropical Atlantic.
* Formation chance through 48 hours...low...20 percent.
* Formation chance through 7 days...medium...60 percent.

&&

Public Advisories on Tropical Depression Six are issued under WMO
header WTNT31 KNHC and under AWIPS header MIATCPAT1.
Forecast/Advisories on Tropical Depression Six are issued under WMO
header WTNT21 KNHC and under AWIPS header MIATCMAT1.

Public Advisories on Tropical Storm Emily are issued under WMO
header WTNT32 KNHC and under AWIPS header MIATCPAT2.
Forecast/Advisories on Tropical Storm Emily are issued under WMO
header WTNT22 KNHC and under AWIPS header MIATCMAT2.

$$
Forecaster Papin/Cangialosi/Hogsett

000
ABPZ20 KNHC 201755
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 AM PDT Sun Aug 20 2023

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

Active Systems:
The National Hurricane Center is issuing advisories on recently
downgraded Tropical Storm Hilary, located on the west coast of the
Baja California peninsula.

South of Southern Mexico:
A broad area of low pressure could form offshore of the coast of
Central America or southern Mexico during the middle part of the
week. Development of this system, if any, should be slow to occur
while it moves slowly toward the northwest or north-northwest.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...low...20 percent.

$$
Forecaster Cangialosi

5-Day Uncertainty Track last updated 0


Wind Speed Probabilities last updated Sat, 19 Aug 2023 21:22:53 GMT

No watches are valid as of Sat Aug 19 22:04:01 UTC 2023.

Issued at 500 PM AST Sat Aug 19 2023 000 WTNT41 KNHC 192046 TCDAT1 Tropical Depression Six Discussion Number 1 NWS National Hurricane Center Miami FL AL062023 500 PM AST Sat Aug 19 2023 Visible imagery has shown a partially-exposed, well-defined low-level circulation for the past several hours. Infrared imagery has also shown deep convection persisting since around 0600 UTC east of the center with cold cloud tops of less than -85 degrees C. Therefore, the system now meets the necessary requirements to be classified as a tropical cyclone. Subjective satellite estimates from TAFB and SAB are 35 kt and 25 kt, respectively, and the initial intensity is set to 30 kt based on that data. Models indicate that the depression is currently in a relatively hostile environment. There is strong deep-layer vertical shear and the mid-level relative humidities are near 40 percent. These conditions are not expected to change much and global models suggest this will be a short-lived depression. Simulated satellite imagery from the ECMWF shows a few bursts of deep convection that are sheared away by 48 hours. The official forecast shows a steady-state depression through 36 hours that degenerates to a remnant low in 48 hours, and dissipates by 60 hours. This prediction is near the various consensus model guidance. The depression is moving west-northwestward at 14 kt. It is currently being steered by a narrow low-level ridge to its north. The system is expected to turn more westward and slow in forward speed over the next day or so followed by a slight bend back to the west-northwest on day 2. The NHC track forecast is near the simple and corrected model consensus aids, and leans towards the more southerly ECMWF track. FORECAST POSITIONS AND MAX WINDS INIT 19/2100Z 16.7N 50.2W 30 KT 35 MPH 12H 20/0600Z 17.0N 52.6W 30 KT 35 MPH 24H 20/1800Z 17.3N 54.8W 30 KT 35 MPH 36H 21/0600Z 17.6N 56.7W 30 KT 35 MPH 48H 21/1800Z 18.1N 58.6W 25 KT 30 MPH...POST-TROP/REMNT LOW 60H 22/0600Z...DISSIPATED $$ Forecaster Bucci

5-Day Uncertainty Track last updated Sat, 19 Aug 2023 20:45:34 GMT


Wind Speed Probabilities last updated Sat, 19 Aug 2023 21:29:07 GMT

Issued at 300 PM MDT Sat Aug 19 2023 000 WTPZ44 KNHC 192043 TCDEP4 Hurricane Hilary Discussion Number 14 NWS National Hurricane Center Miami FL EP092023 300 PM MDT Sat Aug 19 2023 Hilary appears to be weakening quickly. The eye is filling and the cloud tops in the eyewall and rainbands have been warming during the past several hours. In addition, the hurricane has become increasingly asymmetric with dry air continuing to wrap into the western half of the circulation. The Air Force Hurricane Hunters have been investigating Hilary during the past few hours and found that the minimum pressure has risen to 959 mb. Blending the aircraft flight-level wind and SFMR data, as well as some of the satellite estimates yields an initial intensity of 95 kt, but that could be a little generous. Areas of heavy rain are already spreading across portions of the Baja California Peninsula and the Southwestern U.S. Hilary is also producing a large area of high seas along the coast of Baja California and the Gulf of California, with maximum significant wave heights estimated to be higher than 40 ft. The hurricane is still moving north-northwestward, or 345/15 kt. The steering currents are well established and consist of a strong mid-level high pressure area over the south-central U.S. and a mid- to upper-level low off the central California coast. The flow between these features should cause Hilary to accelerate to the north-northwest or north during the next day or two, with the core of the system reaching the central portion of the Baja California Peninsula tonight and southern California Sunday afternoon or evening. The NHC track forecast is largely the same as the previous one and near the middle of the guidance envelope. Users are reminded that the exact details of the track forecast, including where Hilary might make landfall, are of little overall importance since strong winds and heavy rainfall will extend far from the center. These hazards will also begin well in advance of the arrival of the center. Hilary is expected to continue weakening rather quickly while it moves northward due to significantly cooler waters, drier air, and an increase in vertical wind shear. However, Hilary is still expected to be a hurricane when it makes landfall or moves very near the central portion of the Baja California Peninsula. There is high confidence that Hilary will move into southern California as a tropical storm. KEY MESSAGES: 1. Preparations for flooding impacts should be completed as soon as possible, as heavy rainfall will begin well in advance of the center. In the Southwestern U.S., the potentially historic amount of rainfall is expected to cause flash, urban, and arroyo flooding including landslides, mudslides, and debris flows. Dangerous to locally catastrophic flooding impacts are expected late tonight through early Monday. 2. Hurricane conditions are expected along the west-central coast of the Baja California Peninsula within the hurricane warning area tonight and Sunday morning, and are possible in the Hurricane Watch area on Sunday. 3. Tropical storm conditions are expected to begin Sunday in portions of the southwestern U.S. within the Tropical Storm Warning area. Winds could be particularly strong and gusty in and near areas of higher terrain. Gusty winds are expected to spread well inland across the western U.S. 4. Large swells generated by Hilary will affect portions of the Baja California Peninsula and southern California over the next couple of days. These swells are likely to cause life-threatening surf and rip current conditions. FORECAST POSITIONS AND MAX WINDS INIT 19/2100Z 23.8N 114.1W 95 KT 110 MPH 12H 20/0600Z 26.4N 114.8W 80 KT 90 MPH 24H 20/1800Z 30.8N 116.2W 60 KT 70 MPH 36H 21/0600Z 36.4N 117.6W 35 KT 40 MPH...POST-TROP/INLAND 48H 21/1800Z...DISSIPATED $$ Forecaster Cangialosi

Issued at 2100 UTC SAT AUG 19 2023 000 FONT11 KNHC 192043 PWSAT1 TROPICAL DEPRESSION SIX WIND SPEED PROBABILITIES NUMBER 1 NWS NATIONAL HURRICANE CENTER MIAMI FL AL062023 2100 UTC SAT AUG 19 2023 AT 2100Z THE CENTER OF TROPICAL DEPRESSION SIX WAS LOCATED NEAR LATITUDE 16.7 NORTH...LONGITUDE 50.2 WEST WITH MAXIMUM SUSTAINED WINDS NEAR 30 KTS...35 MPH...55 KM/H. Z INDICATES COORDINATED UNIVERSAL TIME (GREENWICH) ATLANTIC STANDARD TIME (AST)...SUBTRACT 4 HOURS FROM Z TIME EASTERN DAYLIGHT TIME (EDT)...SUBTRACT 4 HOURS FROM Z TIME CENTRAL DAYLIGHT TIME (CDT)...SUBTRACT 5 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 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 18Z SAT 06Z SUN 18Z SUN 06Z MON 18Z MON 18Z TUE 18Z WED PERIODS TO TO TO TO TO TO TO 06Z SUN 18Z SUN 06Z MON 18Z MON 18Z TUE 18Z WED 18Z THU FORECAST HOUR (12) (24) (36) (48) (72) (96) (120) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - LOCATION KT $$ FORECASTER BUCCI

Issued at 2100 UTC SAT AUG 19 2023 434 FOPZ14 KNHC 192043 PWSEP4 HURRICANE HILARY WIND SPEED PROBABILITIES NUMBER 14 NWS NATIONAL HURRICANE CENTER MIAMI FL EP092023 2100 UTC SAT AUG 19 2023 AT 2100Z THE CENTER OF HURRICANE HILARY WAS LOCATED NEAR LATITUDE 23.8 NORTH...LONGITUDE 114.1 WEST WITH MAXIMUM SUSTAINED WINDS NEAR 95 KTS...110 MPH...175 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 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 18Z SAT 06Z SUN 18Z SUN 06Z MON 18Z MON 18Z TUE 18Z WED PERIODS TO TO TO TO TO TO TO 06Z SUN 18Z SUN 06Z MON 18Z MON 18Z TUE 18Z WED 18Z THU FORECAST HOUR (12) (24) (36) (48) (72) (96) (120) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - LOCATION KT OXNARD CA 34 X 4( 4) 4( 8) X( 8) X( 8) X( 8) X( 8) SANTA CRUZ IS 34 X 3( 3) 3( 6) X( 6) X( 6) X( 6) X( 6) LONG BEACH/LA 34 X 6( 6) 16(22) X(22) X(22) X(22) X(22) S CATALINA IS 34 X 9( 9) 13(22) X(22) X(22) X(22) X(22) SAN DIEGO CA 34 X 23(23) 37(60) X(60) X(60) X(60) X(60) SAN DIEGO CA 50 X X( X) 10(10) X(10) X(10) X(10) X(10) SAN DIEGO CA 64 X X( X) 1( 1) X( 1) X( 1) X( 1) X( 1) YUMA AZ 34 X 5( 5) 9(14) X(14) X(14) X(14) X(14) TIJUANA 34 X 14(14) 42(56) X(56) X(56) X(56) X(56) TIJUANA 50 X X( X) 4( 4) X( 4) X( 4) X( 4) X( 4) ENSENADA 34 X 58(58) 19(77) X(77) X(77) X(77) X(77) ENSENADA 50 X 6( 6) 18(24) X(24) X(24) X(24) X(24) ENSENADA 64 X X( X) 4( 4) X( 4) X( 4) X( 4) X( 4) IS GUADALUPE 34 5 16(21) X(21) X(21) X(21) X(21) X(21) PUNTA EUGENIA 34 84 16(99) X(99) X(99) X(99) X(99) X(99) PUNTA EUGENIA 50 5 83(88) X(88) X(88) X(88) X(88) X(88) PUNTA EUGENIA 64 X 47(47) X(47) X(47) X(47) X(47) X(47) P ABREOJOS 34 99 1(99) X(99) X(99) X(99) X(99) X(99) P ABREOJOS 50 18 2(20) X(20) X(20) X(20) X(20) X(20) P ABREOJOS 64 1 1( 2) X( 2) X( 2) X( 2) X( 2) X( 2) CABO SAN LUCAS 34 3 X( 3) X( 3) X( 3) X( 3) X( 3) X( 3) SAN JOSE CABO 34 3 X( 3) X( 3) X( 3) X( 3) X( 3) X( 3) LA PAZ 34 5 X( 5) X( 5) X( 5) X( 5) X( 5) X( 5) LORETO 34 41 X(41) X(41) X(41) X(41) X(41) X(41) P PENASCO 34 2 27(29) X(29) X(29) X(29) X(29) X(29) HERMOSILLO 34 2 1( 3) X( 3) X( 3) X( 3) X( 3) X( 3) BAHIA KINO 34 19 6(25) X(25) X(25) X(25) X(25) X(25) GUAYMAS 34 11 3(14) X(14) X(14) X(14) X(14) X(14) 25N 115W 34 99 X(99) X(99) X(99) X(99) X(99) X(99) 25N 115W 50 85 X(85) X(85) X(85) X(85) X(85) X(85) 25N 115W 64 25 X(25) X(25) X(25) X(25) X(25) X(25) 25N 120W 34 3 X( 3) X( 3) X( 3) X( 3) X( 3) X( 3) 30N 120W 34 X 8( 8) X( 8) X( 8) X( 8) X( 8) X( 8) $$ FORECASTER CANGIALOSI

Issued at 300 PM MDT Sat Aug 19 2023 000 WTPZ34 KNHC 192043 TCPEP4 BULLETIN Hurricane Hilary Advisory Number 14 NWS National Hurricane Center Miami FL EP092023 300 PM MDT Sat Aug 19 2023 ...HEAVY RAINS ALREADY AFFECTING PORTIONS OF BAJA CALIFORNIA AND THE SOUTHWESTERN U.S... ...CATASTROPHIC AND LIFE-THREATENING FLOODING LIKELY... SUMMARY OF 300 PM MDT...2100 UTC...INFORMATION ---------------------------------------------- LOCATION...23.8N 114.1W ABOUT 285 MI...455 KM SSE OF PUNTA EUGENIA MEXICO ABOUT 640 MI...1030 KM SSE OF SAN DIEGO CALIFORNIA MAXIMUM SUSTAINED WINDS...110 MPH...175 KM/H PRESENT MOVEMENT...NNW OR 345 DEGREES AT 17 MPH...28 KM/H MINIMUM CENTRAL PRESSURE...959 MB...28.32 INCHES WATCHES AND WARNINGS -------------------- CHANGES WITH THIS ADVISORY: None. SUMMARY OF WATCHES AND WARNINGS IN EFFECT: A Hurricane Warning is in effect for... * Baja California peninsula from Punta Abreojos to Cabo San Quintin A Hurricane Watch is in effect for... * Baja California peninsula north of Cabo San Quintin to Ensenada A Tropical Storm Warning is in effect for... * Baja California peninsula from Punta Abreojos southward * Baja California peninsula entire east coast * Baja California peninsula north of Cabo San Quintin to the California/Mexico border * Mainland Mexico north of Guaymas * California/Mexico border to Point Mugu * Catalina Island A Tropical Storm Watch is in effect for... * Mainland Mexico from Huatabampito to Guaymas A Hurricane Warning means that hurricane conditions are expected somewhere within the warning area. A warning is typically issued 36 hours before the anticipated first occurrence of tropical-storm-force winds, conditions that make outside preparations difficult or dangerous. Preparations to protect life and property should be rushed to completion. A Hurricane Watch means that hurricane conditions are possible within the watch area. A watch is typically issued 48 hours before the anticipated first occurrence of tropical-storm-force winds, conditions that make outside preparations difficult or dangerous. A Tropical Storm Warning means that tropical storm conditions are expected somewhere within the warning area within 36 hours. A Tropical Storm Watch means that tropical storm conditions are possible within the watch area, generally within 48 hours. Interests elsewhere in the southwestern U.S. should monitor the progress of Hilary. For storm information specific to your area in the United States, including possible inland watches and warnings, please monitor products issued by your local National Weather Service forecast office. For storm information specific to your area outside of the United States, please monitor products issued by your national meteorological service. DISCUSSION AND OUTLOOK ---------------------- At 300 PM MDT (2100 UTC), the center of Hurricane Hilary was located near latitude 23.8 North, longitude 114.1 West. Hilary is moving toward the north-northwest near 17 mph (28 km/h). The hurricane is expected to accelerate as it moves north-northwestward to northward during the next day or two. On the forecast track, the center of Hilary will move close to the west-central coast of the Baja California Peninsula tonight and Sunday morning then move across southern California Sunday afternoon and Sunday night. Maximum sustained winds are near 110 mph (175 km/h) with higher gusts. Continued weakening is expected, but Hilary will still be a hurricane when it approaches the west coast of the Baja California Peninsula. Hilary is expected to weaken to a tropical storm before it reaches southern California. Hurricane-force winds extend outward up to 45 miles (75 km) from the center and tropical-storm-force winds extend outward up to 265 miles (425 km). A sustained wind of 46 mph (74 km/h) and a gust of 61 mph (98 km/h) were recently reported at Puerto Cortes. The estimated minimum central pressure based on data from the Air Force Hurricane Hunters is 959 mb (28.32 inches). HAZARDS AFFECTING LAND ---------------------- Key messages for Hilary can be found in the Tropical Cyclone Discussion under AWIPS header MIATCDEP4 and WMO header WTPZ44 KNHC and on the web at hurricanes.gov/text/MIATCDEP4.shtml. RAINFALL: Hilary is expected to produce storm total rainfall amounts of 3 to 6 inches, with isolated maximum amounts up to 10 inches, across portions of the northern Baja California Peninsula through Sunday night. Flash and urban flooding, locally catastrophic, is expected, especially in the northern portions of the peninsula. Heavy rainfall is expected across the Southwestern United States, peaking late tonight through Sunday night. Rainfall amounts of 3 to 6 inches, with isolated amounts of 10 inches, are expected across portions of southern California and southern Nevada. Dangerous to catastrophic flooding is expected. Elsewhere across portions of the Western United States, rainfall totals of 1 to 3 inches are expected, resulting in localized significant flash flooding. WIND: Hurricane conditions are expected within the hurricane warning area tonight and early Sunday and are possible within the hurricane watch on Sunday. Tropical storm conditions are occurring within the southern portion of the tropical storm warning area and will spread northward today and Sunday. Tropical storm conditions are possible within the tropical storm watch area through tonight. Tropical storm conditions are expected to begin in southern California on Sunday. Winds could be particularly strong and gusty in and near areas of elevated terrain. Higher gusts are expected well inland and will persist even after the system becomes post-tropical. STORM SURGE: A dangerous storm surge is likely to produce coastal flooding along the western Baja California peninsula of Mexico near where the center passes the coast in areas of onshore winds, or east of the center if Hilary makes landfall. The surge will be accompanied by large and destructive waves. Coastal flooding is possible along the northern coast of the Gulf of California Sunday through early Monday. TORNADOES: A tornado or two may occur Sunday from mid-morning through the evening over parts of the lower Colorado River Valley, Mojave Desert, and Imperial Valley regions. SURF: Large swells generated by Hilary will affect portions of the Baja California Peninsula and southern California over the next couple of days. These swells are likely to cause life-threatening surf and rip current conditions. Please consult products from your local weather office. NEXT ADVISORY ------------- Next intermediate advisory at 600 PM MDT. Next complete advisory at 900 PM MDT. $$ Forecaster Cangialosi

...HEAVY RAINS ALREADY AFFECTING PORTIONS OF BAJA CALIFORNIA AND THE SOUTHWESTERN U.S... ...CATASTROPHIC AND LIFE-THREATENING FLOODING LIKELY... As of 3:00 PM MDT Sat Aug 19 the center of Hilary was located near 23.8, -114.1 with movement NNW at 17 mph. The minimum central pressure was 959 mb with maximum sustained winds of about 110 mph.

Issued at 2100 UTC SAT AUG 19 2023 000 WTPZ24 KNHC 192042 TCMEP4 HURRICANE HILARY FORECAST/ADVISORY NUMBER 14 NWS NATIONAL HURRICANE CENTER MIAMI FL EP092023 2100 UTC SAT AUG 19 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 23.8N 114.1W AT 19/2100Z POSITION ACCURATE WITHIN 15 NM PRESENT MOVEMENT TOWARD THE NORTH-NORTHWEST OR 345 DEGREES AT 15 KT ESTIMATED MINIMUM CENTRAL PRESSURE 959 MB MAX SUSTAINED WINDS 95 KT WITH GUSTS TO 115 KT. 64 KT....... 40NE 40SE 25SW 40NW. 50 KT....... 70NE 70SE 50SW 70NW. 34 KT.......230NE 200SE 120SW 170NW. 12 FT SEAS..330NE 390SE 330SW 270NW. 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 23.8N 114.1W AT 19/2100Z AT 19/1800Z CENTER WAS LOCATED NEAR 22.9N 113.9W FORECAST VALID 20/0600Z 26.4N 114.8W MAX WIND 80 KT...GUSTS 100 KT. 64 KT... 40NE 30SE 0SW 30NW. 50 KT... 70NE 70SE 60SW 70NW. 34 KT...210NE 190SE 120SW 150NW. FORECAST VALID 20/1800Z 30.8N 116.2W MAX WIND 60 KT...GUSTS 75 KT. 50 KT... 50NE 50SE 0SW 30NW. 34 KT...200NE 180SE 90SW 120NW. FORECAST VALID 21/0600Z 36.4N 117.6W...POST-TROP/INLAND MAX WIND 35 KT...GUSTS 50 KT. 34 KT...150NE 150SE 0SW 0NW. FORECAST VALID 21/1800Z...DISSIPATED REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 23.8N 114.1W INTERMEDIATE PUBLIC ADVISORY...WTNT34 KNHC/MIATCPEP4...AT 20/0000Z NEXT ADVISORY AT 20/0300Z $$ FORECASTER CANGIALOSI

Issued at 500 PM AST Sat Aug 19 2023 635 WTNT31 KNHC 192042 TCPAT1 BULLETIN Tropical Depression Six Advisory Number 1 NWS National Hurricane Center Miami FL AL062023 500 PM AST Sat Aug 19 2023 ...NEW DEPRESSION FORMS... ...EXPECTED TO BE SHORT-LIVED... SUMMARY OF 500 PM AST...2100 UTC...INFORMATION ---------------------------------------------- LOCATION...16.7N 50.2W ABOUT 855 MI...1375 KM E OF THE NORTHERN LEEWARD ISLANDS MAXIMUM SUSTAINED WINDS...35 MPH...55 KM/H PRESENT MOVEMENT...WNW OR 290 DEGREES AT 16 MPH...26 KM/H MINIMUM CENTRAL PRESSURE...1006 MB...29.71 INCHES WATCHES AND WARNINGS -------------------- There are no coastal watches or warnings in effect. DISCUSSION AND OUTLOOK ---------------------- At 500 PM AST (2100 UTC), the center of Tropical Depression Six was located near latitude 16.7 North, longitude 50.2 West. The depression is moving toward the west-northwest near 16 mph (26 km/h) and a turn to the west is expected later today with a gradual decrease in forward motion over the next day or so. On Monday, the depression is expected to turn back to the west-northwest. Maximum sustained winds are near 35 mph (55 km/h) with higher gusts. The depression is expected to be short-lived and become a remnant low by Monday. The estimated minimum central pressure is 1006 mb (29.71 inches). HAZARDS AFFECTING LAND ---------------------- None NEXT ADVISORY ------------- Next complete advisory at 1100 PM AST. $$ Forecaster Bucci

...NEW DEPRESSION FORMS... ...EXPECTED TO BE SHORT-LIVED... As of 5:00 PM AST Sat Aug 19 the center of Six was located near 16.7, -50.2 with movement WNW at 16 mph. The minimum central pressure was 1006 mb with maximum sustained winds of about 35 mph.

Issued at 2100 UTC SAT AUG 19 2023 000 WTNT21 KNHC 192042 TCMAT1 TROPICAL DEPRESSION SIX FORECAST/ADVISORY NUMBER 1 NWS NATIONAL HURRICANE CENTER MIAMI FL AL062023 2100 UTC SAT AUG 19 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 16.7N 50.2W AT 19/2100Z POSITION ACCURATE WITHIN 20 NM PRESENT MOVEMENT TOWARD THE WEST-NORTHWEST OR 290 DEGREES AT 14 KT ESTIMATED MINIMUM CENTRAL PRESSURE 1006 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 16.7N 50.2W AT 19/2100Z AT 19/1800Z CENTER WAS LOCATED NEAR 16.6N 49.9W FORECAST VALID 20/0600Z 17.0N 52.6W MAX WIND 30 KT...GUSTS 40 KT. FORECAST VALID 20/1800Z 17.3N 54.8W MAX WIND 30 KT...GUSTS 40 KT. FORECAST VALID 21/0600Z 17.6N 56.7W MAX WIND 30 KT...GUSTS 40 KT. FORECAST VALID 21/1800Z 18.1N 58.6W...POST-TROP/REMNT LOW MAX WIND 25 KT...GUSTS 35 KT. FORECAST VALID 22/0600Z...DISSIPATED REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 16.7N 50.2W NEXT ADVISORY AT 20/0300Z $$ FORECASTER BUCCI

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0317 PM CDT Sat Aug 19 2023 Valid 211200Z - 271200Z An upper ridge will remain firmly in place across the central/southern CONUS through the upcoming week, promoting hot, dry, and occasionally breezy surface conditions across the central High Plains into Texas. Meanwhile, the remnants of Hilary will traverse the interior west, accompanied and preceded by a rich and deeply moist airmass/precipitation, both of which may prove detrimental to significant, widespread wildfire-spread potential. The best chance for Elevated-equivalent dry/windy surface conditions would be Day 3/Monday across the central High Plains and central Texas, where east-southeasterly winds amid a hot/mixed boundary layer will overspread receptive fuels. Thereafter, medium-range guidance differs on the placement and timing of overlapping favorable surface winds/RH across the south-central CONUS, precluding the addition of Critical probabilities. ..Squitieri.. 08/19/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

MD 2016 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR SAN JOAQUIN VALLEY INTO THE WESTERN MOJAVE DESERT
Mesoscale Discussion 2016 NWS Storm Prediction Center Norman OK 0319 PM CDT Sat Aug 19 2023 Areas affected...San Joaquin Valley into the western Mojave Desert Concerning...Severe potential...Watch unlikely Valid 192019Z - 192245Z Probability of Watch Issuance...5 percent SUMMARY...Storms capable of isolated strong to severe gusts will be possible later this afternoon. DISCUSSION...Initially steep midlevel lapse rates and increasing moisture in advance of Hurricane Hilary will result in widely scattered thunderstorm development this afternoon across parts of the San Joaquin Valley and western Mojave desert region. Recent thunderstorm development has already been noted across northeast Kern County, with storm coverage expected to increase over lower elevation areas with time. With low-level flow/shear expected to remain weak through the afternoon, storms may quickly become outflow dominant. However, increasing mid/upper-level flow (as noted on the KSOX and KEYX VWPs) may support modestly organized and sustained convection, with one or more outflow-driven clusters possible by late afternoon. Strong to locally severe gusts will be possible as storms spread northward through the afternoon into early evening across the San Joaquin Valley. ..Dean/Grams.. 08/19/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...VEF...SGX...HNX...LOX...STO...MTR... LAT...LON 36291776 35181694 34881717 34731770 34651820 35151930 36312069 37072115 37732112 38072037 37501907 36291776 Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0241 PM CDT Sat Aug 19 2023 Valid 192000Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER THE SAN JOAQUIN VALLEY AND WESTERN MOJAVE DESERT... ...SUMMARY... Isolated severe wind gusts are possible over the San Joaquin Valley and western Mojave Desert vicinity the remainder of the afternoon into early evening. ...20z Update -- San Joaquin Valley/Western Mojave Desert... The previous outlook remains unchanged with the 20z update. Convection will increase in coverage over the next 2-3 hours, and sporadic severe thunderstorm gusts are possible into early evening. For more details, see previous outlook below and any forthcoming MCDs. ..Leitman.. 08/19/2023 .PREV DISCUSSION... /ISSUED 1114 AM CDT Sat Aug 19 2023/ ...San Joaquin Valley and western Mojave Desert... Hot temperatures will persist over the Central Valley this afternoon with abundant insolation underway northwest of the extensive cloud canopy downstream of Hurricane Hilary. Convective temperatures will be breached towards early afternoon over the higher terrain across parts of the Transverse Ranges and southern Sierra NV mountains. Isolated to eventually scattered thunderstorms will occur through the afternoon, spreading north-northwest amid south to southeast steering flow that notably strengthens with height in the upper portion of the buoyancy profile. Deeply mixed, inverted-v thermodynamic profiles beneath the moderate storm motions should support a threat for sporadic severe wind gusts before waning during the early evening. ...West... Elsewhere in the West, very localized severe wind gusts will be possible with several areas of scattered thunderstorms this afternoon. Spatial coverage of the severe wind threat appears likely to remain below the 5 percent threshold needed for an areal delineation. Read more

000
ABNT20 KNHC 191934
TWOAT

Special Tropical Weather Outlook
NWS National Hurricane Center Miami FL
335 PM EDT Sat Aug 19 2023

For the North Atlantic...Caribbean Sea and the Gulf of Mexico:

Special outlook issued to update the discussion of the disturbance
in the Central Tropical Atlantic (AL99).

Eastern Tropical Atlantic (AL98):
Shower and thunderstorm activity continues in association with a
broad area of low pressure located several hundred miles west of the
Cabo Verde Islands. Environmental conditions appear generally
favorable for further development of this system, and a short-lived
tropical depression is likely to form this weekend while it moves
west-northwestward or northwestward at about 10 mph across the
eastern tropical Atlantic. By early next week, upper-level winds
over the system are forecast to increase, and further development is
not expected.
* Formation chance through 48 hours...high...70 percent.
* Formation chance through 7 days...high...70 percent.

Central Tropical Atlantic (AL99):
Updated: Showers and thunderstorms associated with an area of low
pressure located roughly halfway between the Cabo Verde Islands and
the Lesser Antilles have persisted and become better organized
this afternoon. If these development trends continue, a
short-lived tropical depression is likely to form this afternoon or
evening, while the system moves west-northwestward at 10 to 15 mph
across the tropical Atlantic. Upper-level winds are expected to
become increasingly unfavorable by late this weekend, with any
further development not anticipated.
* Formation chance through 48 hours...high...70 percent.
* Formation chance through 7 days...high...70 percent.

Near the Windward Islands (AL90):
A broad area of low pressure has formed near the Windward Islands,
shower and thunderstorm activity has become better organized since
yesterday. Some additional development of this system is likely and
a tropical depression could form by early next week while this
system moves westward to west-northwestward at 10 to 15 mph, across
the Lesser Antilles and over the eastern and central Caribbean Sea.
Regardless of development, heavy rainfall is possible over portions
of the Windward Islands during the next couple of days. Interests
in the eastern and central Caribbean should monitor the progress of
this system.
* Formation chance through 48 hours...medium...40 percent.
* Formation chance through 7 days...medium...60 percent.

Western Gulf of Mexico:
An area of disturbed weather located near the northwestern and
central Bahamas is expected to move into the Gulf of Mexico by early
next week, where a broad area of low pressure is expected to form.
Some slow development of this system is possible thereafter, and a
tropical depression could form as it moves westward and approaches
the western Gulf of Mexico coastline by the middle of next week.
* Formation chance through 48 hours...low...10 percent.
* Formation chance through 7 days...medium...50 percent.

Near the coast of Africa:
A tropical wave located near the western coast of Africa is
producing a large area of disorganized showers and thunderstorms.
Some slow development is possible while it moves generally
west-northwestward across the tropical eastern Atlantic during the
next several days.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...low...20 percent.

$$
Forecaster Kelly/Brown