Aggregator

Issued at 300 PM MDT Thu Aug 17 2023 000 WTPZ44 KNHC 172056 TCDEP4 Hurricane Hilary Discussion Number 6 NWS National Hurricane Center Miami FL EP092023 300 PM MDT Thu Aug 17 2023 Hilary has an impressive appearance on satellite imagery. The eye, which is becoming better defined, is surrounded by very cold cloud tops in the CDO. There are numerous convective banding features, especially over the eastern semicircle of the circulation. Upper-level outflow is well-defined over all but the northwestern quadrant of the circulation. Recent objective Dvorak T-numbers support an intensity of about 95 kt, which is used for this advisory. The hurricane continues to move on a west-northwestward track with an initial motion estimate of 300/13 kt. Global models indicate that a mid-tropospheric ridge currently situated to the north of Hilary will shift eastward over the next few days while a cutoff low remains near the California coast. This should result in a steering pattern that will cause the system to gradually turn toward the northwest, north-northwest, and north with increasing forward speed during the next 72 hours. The official forecast track has not changed much from the past few advisory packages, and is a blend of the simple and corrected dynamical model consensus solutions. Since the forecast track is roughly paralleling the coastline north of the central Baja peninsula to the California border, it nearly impossible to know at this point if the center will remain just offshore or move over the peninsula before reaching the southwestern United States. Hilary is over very warm waters, near 30 deg C, with extremely low vertical wind shear and a moist mid- to low-level atmospheric environment. Therefore additional intensification is highly likely for the next day or so. The various SHIPS rapid intensification (RI) indices continue to show high probabilities of RI during the next day or so. The most likely indicated intensity increase is around 25 kt over the next 24 hours, which is also shown in the NHC forecast. Later in the forecast period, cooler waters and land interaction should result in some weakening. The official wind speed forecast remain near or above latest HCCA guidance. The surface circulation is likely to be dissipated by day 5, but a day 5 forecast point (as a remnant low) is still provided to maintain a forecast track over the southwestern United States. KEY MESSAGES: 1. Heavy rainfall associated with Hilary may produce areas of flash flooding and result in landslides over portions of Baja California Peninsula from late Friday into late Sunday. Rainfall impacts from Hilary within the Southwestern United States are expected to peak this weekend into Monday. Flash, urban, and arroyo flooding is possible with the potential for significant impacts. 2. The threat of hurricane-force wind impacts is increasing along the west-central coast of the Baja California Peninsula and hurricane watches could be issued for a portion of that area tonight. Tropical storm conditions are expected to spread across the southern portion of the Baja California Peninsula by late Friday where a Tropical Storm Warning is in effect. 3. The threat of significant wind impacts continues to increase for the northern portions of the Baja California Peninsula and the Southwestern United States, especially in areas of mountainous terrain. Although it is too soon to determine the location and magnitude of these impacts, interests in these areas should monitor the progress of Hilary and updates to the forecast. Watches could be issued for portions of this area on Friday. 4. Large swells from Hilary will spread northward along the coast of southwestern Mexico and the Baja California Peninsula. These swells will reach the Gulf of California and northern portions of the Baja California Peninsula later this weekend. FORECAST POSITIONS AND MAX WINDS INIT 17/2100Z 16.1N 108.9W 95 KT 110 MPH 12H 18/0600Z 17.0N 110.4W 110 KT 125 MPH 24H 18/1800Z 18.4N 112.0W 120 KT 140 MPH 36H 19/0600Z 20.3N 113.0W 120 KT 140 MPH 48H 19/1800Z 22.4N 113.8W 115 KT 130 MPH 60H 20/0600Z 25.0N 114.5W 105 KT 120 MPH 72H 20/1800Z 28.5N 115.4W 85 KT 100 MPH 96H 21/1800Z 35.4N 118.4W 30 KT 35 MPH...INLAND 120H 22/1800Z 43.0N 120.0W 20 KT 25 MPH...POST-TROP/INLAND $$ Forecaster Pasch

Issued at 2100 UTC THU AUG 17 2023 000 FOPZ14 KNHC 172055 PWSEP4 HURRICANE HILARY WIND SPEED PROBABILITIES NUMBER 6 NWS NATIONAL HURRICANE CENTER MIAMI FL EP092023 2100 UTC THU AUG 17 2023 AT 2100Z THE CENTER OF HURRICANE HILARY WAS LOCATED NEAR LATITUDE 16.1 NORTH...LONGITUDE 108.9 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 THU 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 THU 06Z FRI 18Z FRI 06Z SAT 18Z SAT 18Z SUN 18Z MON PERIODS TO TO TO TO TO TO TO 06Z FRI 18Z FRI 06Z SAT 18Z SAT 18Z SUN 18Z MON 18Z TUE FORECAST HOUR (12) (24) (36) (48) (72) (96) (120) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - LOCATION KT OXNARD CA 34 X X( X) X( X) X( X) X( X) 26(26) 1(27) OXNARD CA 50 X X( X) X( X) X( X) X( X) 8( 8) 2(10) OXNARD CA 64 X X( X) X( X) X( X) X( X) 2( 2) 1( 3) SANTA CRUZ IS 34 X X( X) X( X) X( X) X( X) 23(23) 1(24) SANTA CRUZ IS 50 X X( X) X( X) X( X) X( X) 7( 7) 1( 8) SANTA CRUZ IS 64 X X( X) X( X) X( X) X( X) 3( 3) 1( 4) LONG BEACH/LA 34 X X( X) X( X) X( X) X( X) 35(35) 1(36) LONG BEACH/LA 50 X X( X) X( X) X( X) X( X) 13(13) X(13) LONG BEACH/LA 64 X X( X) X( X) X( X) X( X) 4( 4) X( 4) S CATALINA IS 34 X X( X) X( X) X( X) 1( 1) 36(37) 1(38) S CATALINA IS 50 X X( X) X( X) X( X) X( X) 16(16) 1(17) S CATALINA IS 64 X X( X) X( X) X( X) X( X) 6( 6) X( 6) SAN DIEGO CA 34 X X( X) X( X) X( X) 3( 3) 46(49) 1(50) SAN DIEGO CA 50 X X( X) X( X) X( X) X( X) 19(19) X(19) SAN DIEGO CA 64 X X( X) X( X) X( X) X( X) 6( 6) 1( 7) YUMA AZ 34 X X( X) X( X) X( X) 1( 1) 8( 9) X( 9) TIJUANA 34 X X( X) X( X) X( X) 1( 1) 34(35) X(35) TIJUANA 50 X X( X) X( X) X( X) X( X) 11(11) X(11) TIJUANA 64 X X( X) X( X) X( X) X( X) 1( 1) X( 1) ENSENADA 34 X X( X) X( X) X( X) 10(10) 49(59) 1(60) ENSENADA 50 X X( X) X( X) X( X) 1( 1) 25(26) X(26) ENSENADA 64 X X( X) X( X) X( X) X( X) 10(10) X(10) IS GUADALUPE 34 X X( X) X( X) X( X) 19(19) 13(32) X(32) IS GUADALUPE 50 X X( X) X( X) X( X) 2( 2) 5( 7) X( 7) IS GUADALUPE 64 X X( X) X( X) X( X) X( X) 3( 3) X( 3) PUNTA EUGENIA 34 X X( X) X( X) 1( 1) 86(87) 3(90) X(90) PUNTA EUGENIA 50 X X( X) X( X) X( X) 57(57) 3(60) X(60) PUNTA EUGENIA 64 X X( X) X( X) X( X) 30(30) 2(32) X(32) P ABREOJOS 34 X X( X) X( X) 5( 5) 77(82) 1(83) X(83) P ABREOJOS 50 X X( X) X( X) X( X) 47(47) 1(48) X(48) P ABREOJOS 64 X X( X) X( X) X( X) 25(25) X(25) X(25) CABO SAN LUCAS 34 X 1( 1) 6( 7) 8(15) 2(17) X(17) X(17) SAN JOSE CABO 34 X 1( 1) 4( 5) 6(11) 2(13) X(13) X(13) LA PAZ 34 X X( X) 2( 2) 9(11) 6(17) X(17) X(17) LORETO 34 X X( X) X( X) 5( 5) 20(25) 1(26) X(26) LORETO 50 X X( X) X( X) X( X) 4( 4) X( 4) X( 4) P PENASCO 34 X X( X) X( X) X( X) 15(15) 13(28) X(28) P PENASCO 50 X X( X) X( X) X( X) 1( 1) 4( 5) X( 5) P PENASCO 64 X X( X) X( X) X( X) X( X) 1( 1) X( 1) HERMOSILLO 34 X X( X) X( X) X( X) 3( 3) 1( 4) X( 4) BAHIA KINO 34 X X( X) X( X) X( X) 23(23) 2(25) X(25) GUAYMAS 34 X X( X) X( X) X( X) 12(12) 1(13) X(13) HUATABAMPO 34 X X( X) X( X) 1( 1) 2( 3) X( 3) X( 3) LOS MOCHIS 34 X X( X) X( X) 1( 1) 2( 3) X( 3) X( 3) 15N 110W 34 83 1(84) X(84) X(84) X(84) X(84) X(84) 20N 110W 34 16 44(60) 5(65) 1(66) X(66) X(66) X(66) 20N 110W 50 X 2( 2) 2( 4) X( 4) X( 4) X( 4) X( 4) ISLA SOCORRO 34 67 32(99) 1(99) X(99) X(99) X(99) X(99) ISLA SOCORRO 50 3 71(74) 2(76) X(76) X(76) X(76) X(76) ISLA SOCORRO 64 X 24(24) 3(27) X(27) X(27) X(27) X(27) ISLA CLARION 34 2 10(12) 12(24) 2(26) 1(27) X(27) X(27) ISLA CLARION 50 X 1( 1) 2( 3) X( 3) X( 3) X( 3) X( 3) 15N 115W 34 1 2( 3) 1( 4) X( 4) X( 4) X( 4) X( 4) 20N 115W 34 X 5( 5) 32(37) 9(46) 1(47) X(47) X(47) 20N 115W 50 X X( X) 5( 5) 3( 8) X( 8) X( 8) X( 8) 20N 115W 64 X X( X) 1( 1) 1( 2) X( 2) X( 2) X( 2) 25N 115W 34 X X( X) 1( 1) 18(19) 70(89) X(89) X(89) 25N 115W 50 X X( X) X( X) 3( 3) 60(63) 1(64) X(64) 25N 115W 64 X X( X) X( X) X( X) 40(40) X(40) X(40) 25N 120W 34 X X( X) X( X) X( X) 4( 4) X( 4) X( 4) 30N 120W 34 X X( X) X( X) X( X) 4( 4) 11(15) X(15) $$ FORECASTER PASCH

Issued at 300 PM MDT Thu Aug 17 2023 000 WTPZ34 KNHC 172055 TCPEP4 BULLETIN Hurricane Hilary Advisory Number 6 NWS National Hurricane Center Miami FL EP092023 300 PM MDT Thu Aug 17 2023 ...HILARY APPROACHING MAJOR HURRICANE STATUS... SUMMARY OF 300 PM MDT...2100 UTC...INFORMATION ---------------------------------------------- LOCATION...16.1N 108.9W ABOUT 475 MI...765 KM S OF CABO SAN LUCAS MEXICO MAXIMUM SUSTAINED WINDS...110 MPH...175 KM/H PRESENT MOVEMENT...WNW OR 300 DEGREES AT 14 MPH...22 KM/H MINIMUM CENTRAL PRESSURE...960 MB...28.35 INCHES WATCHES AND WARNINGS -------------------- CHANGES WITH THIS ADVISORY: The government of Mexico has extended the Tropical Storm Watch northward on the west coast of the Baja California peninsula to Punta Abreojos, and northward on the east coast of the Baja California peninsula to Loreto. SUMMARY OF WATCHES AND WARNINGS IN EFFECT: A Tropical Storm Warning is in effect for... * Baja California Sur Mexico from Cabo San Lazaro southward * Baja California Sur Mexico from Los Barriles southward A Tropical Storm Watch is in effect for... * North of Cabo San Lazaro to Punta Abreojos * North of Los Barriles to Loreto 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 on the Baja California peninsula, along the coast of northwestern mainland Mexico, and the southwestern United States coastline should closely monitor the progress of Hilary. Additional watches or warnings will likely be required for portions of these areas later tonight and Friday. For storm information specific to your area, 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 16.1 North, longitude 108.9 West. Hilary is moving toward the west-northwest near 14 mph (22 km/h), and this general motion is expected to continue through tonight. A turn toward the northwest is expected Friday morning, followed by a turn toward the north-northwest and north on Saturday. On the forecast track, the center of Hilary will approach the Baja California peninsula over the weekend. Maximum sustained winds have increased to near 110 mph (175 km/h) with higher gusts. Additional rapid strengthening is forecast during the next day or so, and Hilary is likely to become a major hurricane later today. Hurricane-force winds extend outward up to 60 miles (95 km) from the center and tropical-storm-force winds extend outward up to 275 miles (445 km). The estimated minimum central pressure is 960 mb (28.35 inches). HAZARDS AFFECTING LAND ---------------------- RAINFALL: Hilary is expected to produce rainfall amounts of 3 to 6 inches, with isolated maximum amounts up to 10 inches, across portions of the Baja California Peninsula through Sunday night. Flash flooding, locally significant, will be possible. Heavy rainfall in association with Hilary is expected to impact the Southwestern United States from Friday through early next week, peaking on Sunday and Monday. Rainfall amounts of 2 to 4 inches, with isolated amounts in excess of 8 inches, will be possible across portions of southern California and southern Nevada. WIND: Tropical storm conditions are expected within the warning area by late Friday, and are possible within the watch area by early Saturday. SURF: Large swells generated by Hilary will affect portions of the coast of southwestern Mexico and the Baja California peninsula over the next few 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 Pasch

...HILARY APPROACHING MAJOR HURRICANE STATUS... As of 3:00 PM MDT Thu Aug 17 the center of Hilary was located near 16.1, -108.9 with movement WNW at 14 mph. The minimum central pressure was 960 mb with maximum sustained winds of about 110 mph.

Issued at 2100 UTC THU AUG 17 2023 000 WTPZ24 KNHC 172054 TCMEP4 HURRICANE HILARY FORECAST/ADVISORY NUMBER 6 NWS NATIONAL HURRICANE CENTER MIAMI FL EP092023 2100 UTC THU AUG 17 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 16.1N 108.9W AT 17/2100Z POSITION ACCURATE WITHIN 20 NM PRESENT MOVEMENT TOWARD THE WEST-NORTHWEST OR 300 DEGREES AT 12 KT ESTIMATED MINIMUM CENTRAL PRESSURE 960 MB MAX SUSTAINED WINDS 95 KT WITH GUSTS TO 115 KT. 64 KT....... 50NE 40SE 20SW 30NW. 50 KT.......100NE 80SE 40SW 60NW. 34 KT.......240NE 200SE 100SW 120NW. 12 FT SEAS..300NE 300SE 180SW 180NW. WINDS AND SEAS VARY GREATLY IN EACH QUADRANT. RADII IN NAUTICAL MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT. REPEAT...CENTER LOCATED NEAR 16.1N 108.9W AT 17/2100Z AT 17/1800Z CENTER WAS LOCATED NEAR 15.8N 108.4W FORECAST VALID 18/0600Z 17.0N 110.4W MAX WIND 110 KT...GUSTS 135 KT. 64 KT... 50NE 40SE 0SW 30NW. 50 KT...100NE 80SE 40SW 70NW. 34 KT...240NE 200SE 120SW 150NW. FORECAST VALID 18/1800Z 18.4N 112.0W MAX WIND 120 KT...GUSTS 145 KT. 64 KT... 50NE 40SE 20SW 30NW. 50 KT...100NE 80SE 40SW 70NW. 34 KT...250NE 220SE 120SW 170NW. FORECAST VALID 19/0600Z 20.3N 113.0W MAX WIND 120 KT...GUSTS 145 KT. 64 KT... 50NE 40SE 20SW 30NW. 50 KT...100NE 90SE 50SW 70NW. 34 KT...250NE 230SE 140SW 180NW. FORECAST VALID 19/1800Z 22.4N 113.8W MAX WIND 115 KT...GUSTS 140 KT. 64 KT... 50NE 40SE 30SW 30NW. 50 KT...100NE 100SE 60SW 80NW. 34 KT...250NE 220SE 150SW 180NW. FORECAST VALID 20/0600Z 25.0N 114.5W MAX WIND 105 KT...GUSTS 130 KT. 50 KT...100NE 100SE 70SW 80NW. 34 KT...250NE 220SE 160SW 180NW. FORECAST VALID 20/1800Z 28.5N 115.4W MAX WIND 85 KT...GUSTS 105 KT. 50 KT...100NE 100SE 70SW 70NW. 34 KT...200NE 220SE 140SW 160NW. 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 21/1800Z 35.4N 118.4W...INLAND MAX WIND 30 KT...GUSTS 40 KT. OUTLOOK VALID 22/1800Z 43.0N 120.0W...POST-TROP/INLAND MAX WIND 20 KT...GUSTS 30 KT. REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 16.1N 108.9W INTERMEDIATE PUBLIC ADVISORY...WTNT34 KNHC/MIATCPEP4...AT 18/0000Z NEXT ADVISORY AT 18/0300Z $$ FORECASTER PASCH

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0327 PM CDT Thu Aug 17 2023 Valid 191200Z - 251200Z Fire weather concerns will primarily be focused on the western periphery of tropical moisture moving northward in association with now Hurricane Hillary. Additional concerns may also develop as winds increase over very dry fuels in parts of Texas. ...West Texas... The proximity of Hurricane Hillary to the Baja Peninsula is expected to have some effect on the surface pressure gradient for the Southwest and perhaps into the southern High Plains. With hot temperatures expected on preceding days, already very dry fuels in western/central Texas will dry further. Given the increase in wind fields expected and the state of fuels, concern for elevated to near-critical fire weather is evident on Saturday and Sunday. ...Thunderstorms... Models differ in the speed of northward moisture transport along with now Hurricane Hillary. The GFS is the more aggressive of the two models and shows cloud cover/cooler temperatures into northern California and the Northwest this weekend. The ECMWF shows more potential for heating. With some lingering mid-level moisture, isolated thunderstorms could develop in parts of northern California into Oregon. Uncertainty remains high, however. The main push of tropical moisture is currently forecast to primarily impact western and central portions of the Great Basin. With a weak trough forecast to remain off the northern California coast there is at least a low conditional probability of thunderstorms for northern California and perhaps parts of the Northwest late this weekend into early next week. Potential will be contingent upon how fuels respond to any cooler/wetter conditions as well as cloud cover on the western flank of the tropical system. ..Wendt.. 08/17/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0258 PM CDT Thu Aug 17 2023 Valid 172000Z - 181200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL/SOUTHERN GREAT LAKES REGION AND ALSO PARTS OF THE NORTHEAST... ...SUMMARY... Isolated strong to severe thunderstorms remain possible late this afternoon across parts of the central/southern Great Lakes region, and later tonight over parts of the Northeast. ...IL/IN/OH/MI... The Marginal Risk has been trimmed slightly from the west across northeast IL, to account for the progression of the cold front. Otherwise, the previous outlook reasoning remains valid. A few strong storms may develop as the cold front moves eastward, with a threat of isolated hail and damaging winds. See the previous discussion below for more information. ...PA/NJ/NY... The 5% wind and 2% tornado probabilities have been expanded slightly eastward, to account for the potential progression of overnight convection through the end of the period. Wind profiles will be favorable for organized convection in the vicinity of a warm front, as storms develop late tonight across eastern PA. The magnitude of the severe threat remains uncertain due to limited instability, but locally damaging winds and perhaps a tornado will be possible as storms move eastward toward southern New England by Friday morning. ..Dean.. 08/17/2023 .PREV DISCUSSION... /ISSUED 1109 AM CDT Thu Aug 17 2023/ ...IN/OH/Lower MI... A large and progressive upper trough is moving across the central Great Lakes region today, with an associated surface cold front digging southeastward across northern IL. A pre-frontal band of thunderstorms extends from central IL into lower MI, and is situated along the axis of the low-level jet. This precipitation will significantly limit daytime heating for much of the day ahead of the front and preclude a more organized severe threat. Nevertheless, a consensus of 12z CAM solutions suggest a narrow corridor of heating in the wake of this pre-frontal activity later this afternoon over parts of IN/OH. Sufficient instability and favorable deep-layer shear will support a few organized storms, with a risk of strong winds and hail in the most intense cells. This threat should end around sunset. ...PA/NJ/NY... Later tonight, large scale forcing associated with the approaching upper trough will spread into eastern PA and vicinity. Greater low-level moisture will be in place across this region as dewpoints in the upper 60s advect northward. Diurnal cooling/de-coupling will likely limit the severe threat. But there is some chance of an occasional rotating storm during the late evening or overnight, capable of gusty winds or perhaps a brief tornado. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0209 PM CDT Thu Aug 17 2023 Valid 181200Z - 191200Z ...CRITICAL FIRE WEATHER AREA FOR COLUMBIA BASIN... ...CRITICAL FIRE WEATHER AREA FOR PARTS OF NORTHERN MONTANA... No changes to the ongoing forecast. ..Wendt.. 08/17/2023 .PREV DISCUSSION... /ISSUED 0149 AM CDT Thu Aug 17 2023/ ...Synopsis... A mid-level trough over the Pacific Northwest is forecast to intensify and shift eastward, suppressing the strong ridge centered over the southern Plains. At the surface, a cyclone in southern Canada will deepen, enhancing westerly winds along the international border. Very hot and dry conditions are expected over parts of the Plains and Intermountain West. Dry and breezy west winds are expected over parts of the Northwest and northern Rockies with widespread elevated to critical fire-weather conditions likely. ...Northwest and northern Rockies... As the Pacific trough moves inland it is forecast to strengthen, resulting in moderate mid-level westerly flow over much of the Northwest. At the same time, the surface cyclone over southern Alberta should deepen, enhancing low-level flow in its wake. Downslope winds of 20-25 mph are likely in the lee of the Cascades and across the western Columbia Basin. Warm temperatures will also support low afternoon RH of 15-20% from eastern WA to central MT. With area fuels rather dry, widespread critical fire-weather conditions are likely. Dry and windy conditions will extend eastward across the northern Rockies as the surface low approaches later in the day. While slightly cooler in the wake of a prior cold front, strong surface winds of 20-30 mph are expected over parts of northern/western MT. With afternoon RH values of 20-25% critical conditions still appear likely. As westerly winds increase, the monsoon moisture that has lingered over northern CA and southern OR will be shunted eastward. Isolated showers and thunderstorms are possible over parts of central and northeast OR into western ID/MT. Model soundings show relatively high PWAT values near 1 inch, but fast storm motions greater than 30 mph. Lightning strikes are possible outside of the wetter cores with these storms as they move over areas of dry fuels. However, storm coverage and the potential for some wetting rain cast considerable uncertainty on the need for IsoDryT highlights. ...Texas... As the ridge continues to build, extremely hot temperatures are forecast to redevelop over parts of southern and central TX. Highs over 100F along with exceptionally dry fuels will be the primary catalyst for locally elevated fire-weather activity. Southerly surface winds, while not robust, may occasionally reach 10-15 mph further increasing concerns for locally elevated fire-weather conditions over central parts of the state. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

000
ABPZ20 KNHC 171753
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 AM PDT Thu Aug 17 2023

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

Active Systems:
The National Hurricane Center is issuing advisories on Hurricane
Hilary, located several hundred miles south-southeast of the
southern tip of Baja California peninsula.

South of Southern Mexico:
A broad area of low pressure could form offshore of the coast of
southern Mexico during the early or middle part of next week. Some
gradual development of this system is possible thereafter while it
moves slowly west-northwestward or northwestward.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...low...20 percent.

$$
Forecaster Bucci

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1229 PM CDT Thu Aug 17 2023 Valid 181200Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PARTS OF NEW ENGLAND AND ARIZONA... ...SUMMARY... Isolated severe thunderstorms with a risk for damaging gusts and perhaps a tornado or two will be possible during the day across portions of New England on Friday. Storms capable of isolated severe gusts will also be possible across parts of Arizona. ...Synopsis... A seasonably deep/strong upper-level trough will move across the Northeast and Mid Atlantic regions on Friday. An associated surface low will move eastward across Quebec, as a trailing cold front moves from the upper Great Lakes into New England through the day. Farther west, a mid/upper-level low will remain nearly stationary off of the California coast. A mid/upper-level shortwave trough and associated surface low will move across the Canadian Prairies, as an attendant cold front moves into the northern Plains. ...Northeast... Multiple rounds of convection are possible across parts of the Northeast/New England on Friday. The initial morning to early afternoon round may be capable of locally damaging gusts and perhaps a tornado or two, with a more isolated threat later Friday afternoon along/ahead of the cold front. One or more storm clusters will likely be ongoing Friday morning somewhere from northern NY into southern New England. Strong deep-layer flow associated with the approaching upper trough will support sufficient effective shear for organized convective elements within these clusters. The strongest buoyancy (with MLCAPE generally 500-1000 J/kg during the morning) is expected near/south of a northward-advancing warm front across southern New England, with weaker instability extending northward into parts of VT/NH. The morning threat will likely be maximized near/south of the warm front, where line-embedded supercells and/or shorter-lived mesovortices will support potential for locally damaging gusts and perhaps a tornado or two, within an environment of favorable low-level shear/SRH. Depending on the extent of heating/destabilization that can occur across southern New England prior to storm arrival, higher severe probabilities may eventually be needed. In the wake of early-day convection, redevelopment along/ahead of the cold front will be possible during the afternoon. Coverage and intensity of convection associated with the cold front remain uncertain, with storms potentially struggling to mature due to generally weak instability and a midlevel dry slot overspreading the region. However, a few strong to locally severe storms will be possible within this frontal regime, with a threat of locally damaging gusts and small to marginally severe hail. ...Arizona... Scattered to numerous thunderstorms are expected Friday from AZ into southern NV/UT, as moisture continues to increase east of the nearly stationary upper-level trough off of the CA coast. Modest southerly midlevel flow will support the potential for loosely organized, north to northwesterly moving clusters during the afternoon and evening. Localized severe gusts will be possible where somewhat stronger preconvective heating/destabilization occurs, which currently appears most likely across the lower elevations of southern/central AZ. Small hail and gusty winds will also be possible into northern AZ, though coverage of any severe threat remains more uncertain across this area. ...Montana... Widely scattered high-based convection is expected across parts of MT Friday afternoon and evening. Hot, deeply mixed boundary layers will support the potential for localized severe gusts, though the threat appears too disorganized and unfocused for severe-wind probabilities at this time. ..Dean.. 08/17/2023 Read more

Wisconsin has had about 250 more wildfires than usual since the start of the year due to persistent drought, according to the Wisconsin Department of Natural Resources. There have been 871 fires that have consumed nearly 4,400 acres to date, compared to the 10-year average of 614 fires and roughly 1,800 acres burned. Wisconsin Public Radio (Madison), Aug 11, 2023

Water was not flowing at Headwaters at the Comal. Water that used to be flowing and clear had become cloudy and filled with algae as extreme heat and drought depleted the flow. Fewer birds, butterflies and dragonflies can be found at the Headwaters riverside grassland ecosystem. Native grasses and plants were brown and dry. At Landa Lake, the Landa Lake Boathouse was closed early for the season due to low water levels. Launching boats was not safe. A burn ban was reinstated in early July and remained in effect. Open flames were prohibited. The extreme fire risk led the county to issue a disaster declaration due to the ongoing heat wave and intensifying drought conditions. New Braunfels Herald-Zeitung (Texas), Aug 14, 2023

Some fishing spots in Bell County have gone dry, due to drought, leaving fewer fishing opportunities. Winkler Park Campsite and Own Creek near Gatesville were dry. Lake Belton was 60% full, compared to 62% two weeks ago. The lake was at 77.7% at this time last year. KWTX TV 10 (Waco, Texas), Aug 16, 2023

5-Day Uncertainty Track last updated Thu, 17 Aug 2023 14:51:52 GMT


Wind Speed Probabilities last updated Thu, 17 Aug 2023 15:22:49 GMT

Issued at 500 AM HST Thu Aug 17 2023 190 WTPZ42 KNHC 171450 TCDEP2 Post-Tropical Cyclone Fernanda Discussion Number 20 NWS National Hurricane Center Miami FL EP072023 500 AM HST Thu Aug 17 2023 Fernanda has lacked convective activity since yesterday evening and is therefore considered a post-tropical cyclone. With no convective activity, Dvorak estimates are no longer a reliable source for intensity guidance. The initial intensity is lowered to 30 kt for this advisory largely based on the trend in geostationary satellite imagery. An occasional burst of convection is still possible given 25-26 degrees C sea surface temperatures along the forecast track of Fernanda. Model guidance indicates the cyclone will continue to weaken in an increasingly dry and stable environment for the next few days and is likely to dissipate by day 3. The remnant low is moving westward at 13 kt. This general motion is expected to continue for the next few days as the system is steered by the low-level flow around a ridge to its north. For additional information on the remnant low please see High Seas Forecasts issued by the National Weather Service. Those forecasts can be found under AWIPS header NFDHSFEPI and WMO header FZPN02 KWBC, and on the web at ocean.weather.gov/shtml/NFDHSFEPI.php. FORECAST POSITIONS AND MAX WINDS INIT 17/1500Z 16.4N 132.2W 30 KT 35 MPH...POST-TROPICAL 12H 18/0000Z 16.4N 134.1W 25 KT 30 MPH...POST-TROP/REMNT LOW 24H 18/1200Z 16.4N 136.6W 25 KT 30 MPH...POST-TROP/REMNT LOW 36H 19/0000Z 16.4N 139.2W 25 KT 30 MPH...POST-TROP/REMNT LOW 48H 19/1200Z 16.3N 141.7W 20 KT 25 MPH...POST-TROP/REMNT LOW 60H 20/0000Z 16.4N 144.4W 20 KT 25 MPH...POST-TROP/REMNT LOW 72H 20/1200Z...DISSIPATED $$ Forecaster Bucci

Issued at 1500 UTC THU AUG 17 2023 000 FOPZ12 KNHC 171450 PWSEP2 POST-TROPICAL CYCLONE FERNANDA WIND SPEED PROBABILITIES NUMBER 20 NWS NATIONAL HURRICANE CENTER MIAMI FL EP072023 1500 UTC THU AUG 17 2023 AT 1500Z THE CENTER OF POST-TROPICAL CYCLONE FERNANDA WAS LOCATED NEAR LATITUDE 16.4 NORTH...LONGITUDE 132.2 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 12Z THU 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 12Z THU 00Z FRI 12Z FRI 00Z SAT 12Z SAT 12Z SUN 12Z MON PERIODS TO TO TO TO TO TO TO 00Z FRI 12Z FRI 00Z SAT 12Z SAT 12Z SUN 12Z MON 12Z TUE FORECAST HOUR (12) (24) (36) (48) (72) (96) (120) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - LOCATION KT $$ FORECASTER BUCCI

Issued at 500 AM HST Thu Aug 17 2023 000 WTPZ32 KNHC 171450 TCPEP2 BULLETIN Post-Tropical Cyclone Fernanda Advisory Number 20 NWS National Hurricane Center Miami FL EP072023 500 AM HST Thu Aug 17 2023 ...FERNANDA BECOMES A REMNANT LOW... ...THIS IS THE LAST NHC ADVISORY... SUMMARY OF 500 AM HST...1500 UTC...INFORMATION ---------------------------------------------- LOCATION...16.4N 132.2W ABOUT 1515 MI...2440 KM WSW OF THE SOUTHERN TIP OF BAJA CALIFORNIA MAXIMUM SUSTAINED WINDS...35 MPH...55 KM/H PRESENT MOVEMENT...W OR 270 DEGREES AT 15 MPH...24 KM/H MINIMUM CENTRAL PRESSURE...1005 MB...29.68 INCHES WATCHES AND WARNINGS -------------------- There are no coastal watches or warnings in effect. DISCUSSION AND OUTLOOK ---------------------- At 500 AM HST (1500 UTC), the center of Post-Tropical Cyclone Fernanda was located near latitude 16.4 North, longitude 132.2 West. The post-tropical cyclone is moving toward the west near 15 mph (24 km/h) and this general motion is expected to continue for the next few days. Maximum sustained winds have decreased to near 35 mph (55 km/h) with higher gusts. Continued weakening is forecast during the next couple of days, and Fernanda is likely to dissipate by the weekend. The estimated minimum central pressure is 1005 mb (29.68 inches). HAZARDS AFFECTING LAND ---------------------- None NEXT ADVISORY ------------- This is the last public advisory issued by the National Hurricane Center on this system. $$ Forecaster Bucci

...FERNANDA BECOMES A REMNANT LOW... ...THIS IS THE LAST NHC ADVISORY... As of 5:00 AM HST Thu Aug 17 the center of Fernanda was located near 16.4, -132.2 with movement W at 15 mph. The minimum central pressure was 1005 mb with maximum sustained winds of about 35 mph.

Issued at 1500 UTC THU AUG 17 2023 000 WTPZ22 KNHC 171449 TCMEP2 POST-TROPICAL CYCLONE FERNANDA FORECAST/ADVISORY NUMBER 20 NWS NATIONAL HURRICANE CENTER MIAMI FL EP072023 1500 UTC THU AUG 17 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). POST-TROPICAL CYCLONE CENTER LOCATED NEAR 16.4N 132.2W AT 17/1500Z POSITION ACCURATE WITHIN 20 NM PRESENT MOVEMENT TOWARD THE WEST OR 270 DEGREES AT 13 KT ESTIMATED MINIMUM CENTRAL PRESSURE 1005 MB MAX SUSTAINED WINDS 30 KT WITH GUSTS TO 40 KT. 12 FT SEAS.. 90NE 30SE 30SW 90NW. 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 16.4N 132.2W AT 17/1500Z AT 17/1200Z CENTER WAS LOCATED NEAR 16.4N 131.5W FORECAST VALID 18/0000Z 16.4N 134.1W...POST-TROP/REMNT LOW MAX WIND 25 KT...GUSTS 35 KT. FORECAST VALID 18/1200Z 16.4N 136.6W...POST-TROP/REMNT LOW MAX WIND 25 KT...GUSTS 35 KT. FORECAST VALID 19/0000Z 16.4N 139.2W...POST-TROP/REMNT LOW MAX WIND 25 KT...GUSTS 35 KT. FORECAST VALID 19/1200Z 16.3N 141.7W...POST-TROP/REMNT LOW MAX WIND 20 KT...GUSTS 30 KT. FORECAST VALID 20/0000Z 16.4N 144.4W...POST-TROP/REMNT LOW MAX WIND 20 KT...GUSTS 30 KT. FORECAST VALID 20/1200Z...DISSIPATED REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 16.4N 132.2W THIS IS THE LAST FORECAST/ADVISORY ISSUED BY THE NATIONAL HURRICANE CENTER ON THIS SYSTEM. FOR ADDITIONAL INFORMATION ON THE REMNANT LOW PLEASE SEE HIGH SEAS FORECASTS ISSUED BY THE NATION WEATHER SERVICE...UNDER AWIPS HEADER NFDHSFEPI AND WMO HEADER FZPN02 KWBC. $$ FORECASTER BUCCI

The City of Lampasas entered Stage 4 Drought Response, or critical water shortage conditions, on Aug. 15, due to the low level of Stillhouse Hollow Reservoir. Lawn watering is permitted once weekly. Water may not be used to wash motor vehicles, except in the immediate interest of public health, safety and welfare. Pools may not be filled or refilled. KWTX-TV 10 News Waco (Texas), Aug 16, 2023