Issued at 0300 UTC SAT SEP 28 2024 683 WTNT25 KNHC 280237 TCMAT5 HURRICANE ISAAC FORECAST/ADVISORY NUMBER 9 NWS NATIONAL HURRICANE CENTER MIAMI FL AL102024 0300 UTC SAT SEP 28 2024 HURRICANE CENTER LOCATED NEAR 38.2N 43.4W AT 28/0300Z POSITION ACCURATE WITHIN 20 NM PRESENT MOVEMENT TOWARD THE EAST-NORTHEAST OR 75 DEGREES AT 14 KT ESTIMATED MINIMUM CENTRAL PRESSURE 973 MB EYE DIAMETER 10 NM MAX SUSTAINED WINDS 80 KT WITH GUSTS TO 100 KT. 64 KT....... 0NE 25SE 20SW 0NW. 50 KT....... 20NE 45SE 40SW 25NW. 34 KT....... 50NE 130SE 110SW 50NW. 12 FT SEAS..120NE 180SE 180SW 150NW. WINDS AND SEAS VARY GREATLY IN EACH QUADRANT. RADII IN NAUTICAL MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT. REPEAT...CENTER LOCATED NEAR 38.2N 43.4W AT 28/0300Z AT 28/0000Z CENTER WAS LOCATED NEAR 37.9N 44.3W FORECAST VALID 28/1200Z 39.5N 40.9W MAX WIND 80 KT...GUSTS 100 KT. 64 KT... 10NE 25SE 20SW 10NW. 50 KT... 30NE 50SE 50SW 40NW. 34 KT... 80NE 130SE 110SW 80NW. FORECAST VALID 29/0000Z 41.0N 38.6W MAX WIND 75 KT...GUSTS 90 KT. 64 KT... 15NE 20SE 20SW 10NW. 50 KT... 50NE 50SE 50SW 50NW. 34 KT...130NE 120SE 110SW 120NW. FORECAST VALID 29/1200Z 42.5N 37.0W MAX WIND 70 KT...GUSTS 85 KT. 64 KT... 0NE 15SE 15SW 0NW. 50 KT... 50NE 50SE 50SW 50NW. 34 KT...170NE 120SE 110SW 140NW. FORECAST VALID 30/0000Z 43.8N 35.4W MAX WIND 60 KT...GUSTS 75 KT. 50 KT... 40NE 40SE 40SW 50NW. 34 KT...170NE 130SE 110SW 150NW. FORECAST VALID 30/1200Z 45.0N 33.7W...POST-TROPICAL MAX WIND 55 KT...GUSTS 65 KT. 50 KT... 40NE 30SE 30SW 40NW. 34 KT...160NE 120SE 100SW 140NW. FORECAST VALID 01/0000Z 46.9N 32.4W...POST-TROP/EXTRATROP MAX WIND 45 KT...GUSTS 55 KT. 34 KT...180NE 90SE 90SW 150NW. EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 125 NM ON DAY 4 AND 175 NM ON DAY 5...AND FOR INTENSITY NEAR 15 KT EACH DAY OUTLOOK VALID 02/0000Z 50.9N 31.0W...POST-TROP/EXTRATROP MAX WIND 40 KT...GUSTS 50 KT. 34 KT...180NE 80SE 90SW 120NW. OUTLOOK VALID 03/0000Z 53.8N 29.5W...POST-TROP/EXTRATROP MAX WIND 35 KT...GUSTS 45 KT. 34 KT... 0NE 0SE 150SW 160NW. REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 38.2N 43.4W NEXT ADVISORY AT 28/0900Z $$ FORECASTER HAGEN

...ISAAC CONTINUES TO STRENGTHEN... As of 3:00 AM GMT Sat Sep 28 the center of Isaac was located near 38.2, -43.4 with movement ENE at 16 mph. The minimum central pressure was 973 mb with maximum sustained winds of about 90 mph.

Issued at 300 AM GMT Sat Sep 28 2024 000 WTNT35 KNHC 280237 TCPAT5 BULLETIN Hurricane Isaac Advisory Number 9 NWS National Hurricane Center Miami FL AL102024 300 AM GMT Sat Sep 28 2024 ...ISAAC CONTINUES TO STRENGTHEN... SUMMARY OF 300 AM GMT...0300 UTC...INFORMATION ---------------------------------------------- LOCATION...38.2N 43.4W ABOUT 890 MI...1430 KM W OF THE AZORES MAXIMUM SUSTAINED WINDS...90 MPH...150 KM/H PRESENT MOVEMENT...ENE OR 75 DEGREES AT 16 MPH...26 KM/H MINIMUM CENTRAL PRESSURE...973 MB...28.74 INCHES WATCHES AND WARNINGS -------------------- There are no coastal watches or warnings in effect. DISCUSSION AND OUTLOOK ---------------------- At 300 AM GMT (0300 UTC), the center of Hurricane Isaac was located near latitude 38.2 North, longitude 43.4 West. Isaac is moving toward the east-northeast near 16 mph (26 km/h). A gradual turn to the northeast is expected with a slight decrease in forward speed over the next day or so. The northeastward motion should then continue through Monday. Maximum sustained winds are near 90 mph (150 km/h) with higher gusts. Little change in strength is expected through Saturday morning, followed by gradual weakening through early next week. Isaac is expected to be a post-tropical cyclone on Monday. Hurricane-force winds extend outward up to 30 miles (45 km) from the center and tropical-storm-force winds extend outward up to 150 miles (240 km). The estimated minimum central pressure is 973 mb (28.74 inches). HAZARDS AFFECTING LAND ---------------------- SURF: Swells generated by Isaac and a large wind fetch from a deep-layer trough could spread into the Azores this weekend. These swells are likely to cause life-threatening surf and rip current conditions. Please consult products from your local weather office. NEXT ADVISORY ------------- Next complete advisory at 900 AM GMT. $$ Forecaster Hagen

Issued at 1100 PM AST Fri Sep 27 2024 000 WTNT41 KNHC 280233 TCDAT1 Tropical Storm Joyce Discussion Number 3 NWS National Hurricane Center Miami FL AL112024 1100 PM AST Fri Sep 27 2024 Recent microwave imagery, including an 0022 UTC ASCAT-B pass, indicates that Joyce's circulation is tilted with height, with a mid-level center feature displaced about 40 nm north of the low-level center. The scatterometer data also indicated that Joyce still has maximum winds of 45 kt, which is also supported by the latest TAFB and SAB Dvorak fixes. Joyce is moving toward the west-northwest (300/10 kt) to the south of a narrow subtropical ridge. Deep-layer troughing is forecast to amplify over the central Atlantic during the next few days, eroding the ridge and causing Joyce to gradually turn toward the northwest and north and slow down to a crawl by this time on Monday. Because several of the regional hurricane models appear to keep Joyce too strong in the coming days (more on that below) and show recurvature with acceleration, the NHC track forecast more closely follows the global models and is a blend of the previous forecast with the GFEX consensus. UW-CIMSS analyses and SHIPS diagnostics indicate that Joyce is being affected by moderate-to-strong southerly shear, which is reflected by the satellite presentation. This shear is not expected to abate during the next few days, and the storm will also be moving into a gradually drier and subsident environment. Therefore, the NHC intensity forecast calls for little change in strength during the next 24 hours, followed by gradual weakening thereafter. Joyce is likely to lose its organized convection and become a remnant low by day 3, if not sooner. The remnant low should degenerate into a trough by day 4 or 5 and will likely be absorbed by a larger weather system moving across the eastern Atlantic. FORECAST POSITIONS AND MAX WINDS INIT 28/0300Z 18.9N 44.7W 45 KT 50 MPH 12H 28/1200Z 19.3N 46.0W 45 KT 50 MPH 24H 29/0000Z 19.7N 47.7W 45 KT 50 MPH 36H 29/1200Z 20.3N 48.8W 40 KT 45 MPH 48H 30/0000Z 21.0N 49.5W 35 KT 40 MPH 60H 30/1200Z 21.6N 49.7W 30 KT 35 MPH 72H 01/0000Z 22.0N 49.7W 25 KT 30 MPH...POST-TROP/REMNT LOW 96H 02/0000Z 22.4N 49.7W 25 KT 30 MPH...POST-TROP/REMNT LOW 120H 03/0000Z...DISSIPATED $$ Forecaster Berg

...JOYCE HOLDING STEADY IN INTENSITY... As of 11:00 PM AST Fri Sep 27 the center of Joyce was located near 18.9, -44.7 with movement WNW at 12 mph. The minimum central pressure was 1004 mb with maximum sustained winds of about 50 mph.

Issued at 1100 PM AST Fri Sep 27 2024 000 WTNT31 KNHC 280232 TCPAT1 BULLETIN Tropical Storm Joyce Advisory Number 3 NWS National Hurricane Center Miami FL AL112024 1100 PM AST Fri Sep 27 2024 ...JOYCE HOLDING STEADY IN INTENSITY... SUMMARY OF 1100 PM AST...0300 UTC...INFORMATION ----------------------------------------------- LOCATION...18.9N 44.7W ABOUT 1205 MI...1940 KM E OF THE NORTHERN LEEWARD ISLANDS MAXIMUM SUSTAINED WINDS...50 MPH...85 KM/H PRESENT MOVEMENT...WNW OR 300 DEGREES AT 12 MPH...19 KM/H MINIMUM CENTRAL PRESSURE...1004 MB...29.65 INCHES WATCHES AND WARNINGS -------------------- There are no coastal watches or warnings in effect. DISCUSSION AND OUTLOOK ---------------------- At 1100 PM AST (0300 UTC), the center of Tropical Storm Joyce was located near latitude 18.9 North, longitude 44.7 West. Joyce is moving toward the west-northwest near 12 mph (19 km/h), and general motion with a decrease in forward speed is expected through early Sunday. A slow turn toward the northwest and north is forecast later on Sunday and Monday. Satellite-derived wind data indicate that maximum sustained winds remain near 50 mph (85 km/h) with higher gusts. Little change in strength is expected through Saturday. Weakening is forecast to begin by Sunday, and Joyce could degenerate into a remnant low by late Monday. Tropical-storm-force winds extend outward up to 105 miles (165 km) from the center. The estimated minimum central pressure is 1004 mb (29.65 inches). HAZARDS AFFECTING LAND ---------------------- None NEXT ADVISORY ------------- Next complete advisory at 500 AM AST. $$ Forecaster Berg

Issued at 0300 UTC SAT SEP 28 2024 000 FONT11 KNHC 280232 PWSAT1 TROPICAL STORM JOYCE WIND SPEED PROBABILITIES NUMBER 3 NWS NATIONAL HURRICANE CENTER MIAMI FL AL112024 0300 UTC SAT SEP 28 2024 AT 0300Z THE CENTER OF TROPICAL STORM JOYCE WAS LOCATED NEAR LATITUDE 18.9 NORTH...LONGITUDE 44.7 WEST WITH MAXIMUM SUSTAINED WINDS NEAR 45 KTS...50 MPH...85 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 00Z SAT AND THE FORECAST HOUR (CUMULATIVE PROBABILITY) PROBABILITIES ARE GIVEN IN PERCENT X INDICATES PROBABILITIES LESS THAN 1 PERCENT PROBABILITIES FOR 34 KT AND 50 KT ARE SHOWN AT A GIVEN LOCATION WHEN THE 5-DAY CUMULATIVE PROBABILITY IS AT LEAST 3 PERCENT. PROBABILITIES FOR 34...50...64 KT SHOWN WHEN THE 5-DAY 64-KT CUMULATIVE PROBABILITY IS AT LEAST 1 PERCENT. - - - - WIND SPEED PROBABILITIES FOR SELECTED LOCATIONS - - - - FROM FROM FROM FROM FROM FROM FROM TIME 00Z SAT 12Z SAT 00Z SUN 12Z SUN 00Z MON 00Z TUE 00Z WED PERIODS TO TO TO TO TO TO TO 12Z SAT 00Z SUN 12Z SUN 00Z MON 00Z TUE 00Z WED 00Z THU FORECAST HOUR (12) (24) (36) (48) (72) (96) (120) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - LOCATION KT $$ FORECASTER BERG

Issued at 0300 UTC SAT SEP 28 2024 000 WTNT21 KNHC 280231 TCMAT1 TROPICAL STORM JOYCE FORECAST/ADVISORY NUMBER 3 NWS NATIONAL HURRICANE CENTER MIAMI FL AL112024 0300 UTC SAT SEP 28 2024 TROPICAL STORM CENTER LOCATED NEAR 18.9N 44.7W AT 28/0300Z POSITION ACCURATE WITHIN 20 NM PRESENT MOVEMENT TOWARD THE WEST-NORTHWEST OR 300 DEGREES AT 10 KT ESTIMATED MINIMUM CENTRAL PRESSURE 1004 MB MAX SUSTAINED WINDS 45 KT WITH GUSTS TO 55 KT. 34 KT....... 40NE 20SE 20SW 90NW. 12 FT SEAS.. 75NE 0SE 0SW 45NW. 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 18.9N 44.7W AT 28/0300Z AT 28/0000Z CENTER WAS LOCATED NEAR 18.7N 44.2W FORECAST VALID 28/1200Z 19.3N 46.0W MAX WIND 45 KT...GUSTS 55 KT. 34 KT... 50NE 20SE 20SW 70NW. FORECAST VALID 29/0000Z 19.7N 47.7W MAX WIND 45 KT...GUSTS 55 KT. 34 KT... 50NE 20SE 20SW 40NW. FORECAST VALID 29/1200Z 20.3N 48.8W MAX WIND 40 KT...GUSTS 50 KT. 34 KT... 50NE 20SE 0SW 30NW. FORECAST VALID 30/0000Z 21.0N 49.5W MAX WIND 35 KT...GUSTS 45 KT. 34 KT... 30NE 20SE 0SW 20NW. FORECAST VALID 30/1200Z 21.6N 49.7W MAX WIND 30 KT...GUSTS 40 KT. FORECAST VALID 01/0000Z 22.0N 49.7W...POST-TROP/REMNT LOW MAX WIND 25 KT...GUSTS 35 KT. EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 125 NM ON DAY 4 AND 175 NM ON DAY 5...AND FOR INTENSITY NEAR 15 KT EACH DAY OUTLOOK VALID 02/0000Z 22.4N 49.7W...POST-TROP/REMNT LOW MAX WIND 25 KT...GUSTS 35 KT. OUTLOOK VALID 03/0000Z...DISSIPATED REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 18.9N 44.7W NEXT ADVISORY AT 28/0900Z $$ FORECASTER BERG

000
ABNT20 KNHC 272325
TWOAT

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
800 PM EDT Fri Sep 27 2024

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

Active Systems:
The National Hurricane Center is issuing advisories on Hurricane
Isaac, located over the central Subtropical Atlantic Ocean, and on
Tropical Storm Joyce, located over the central Tropical Atlantic
Ocean. The Weather Prediction Center is issuing advisories on
Post-Tropical Cyclone Helene, located inland over the Ohio River
Valley.

Eastern and Central Tropical Atlantic:
A broad and elongated area of low pressure, associated with a
tropical wave, is producing limited shower activity near and to the
west of the Cabo Verde Islands. Environmental conditions appear
conducive for gradual development of this system, and a tropical
depression could form next week while moving toward the west and
then northwest at about 10 mph across the eastern and central
tropical Atlantic.
* Formation chance through 48 hours...low...10 percent.
* Formation chance through 7 days...medium...40 percent.

Western Caribbean Sea and Gulf of Mexico:
An area of low pressure could form over the western Caribbean Sea by
the middle of next week. Environmental conditions are expected to
be conducive for slow development thereafter while the system moves
generally northwestward, likely entering the Gulf of Mexico by the
end of next week.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...low...30 percent.

&&
Public Advisories on Tropical Storm Joyce are issued under WMO
header WTNT31 KNHC and under AWIPS header MIATCPAT1.
Forecast/Advisories on Tropical Storm Joyce are issued under WMO
header WTNT21 KNHC and under AWIPS header MIATCMAT1.

$$
Forecaster Berg

5-Day Uncertainty Track last updated Fri, 27 Sep 2024 20:44:50 GMT


Wind Speed Probabilities last updated Fri, 27 Sep 2024 21:29:05 GMT

5-Day Uncertainty Track last updated Fri, 27 Sep 2024 20:36:55 GMT


Wind Speed Probabilities last updated Fri, 27 Sep 2024 21:35:02 GMT

Issued at 500 PM AST Fri Sep 27 2024 368 WTNT41 KNHC 272035 TCDAT1 Tropical Storm Joyce Discussion Number 2 NWS National Hurricane Center Miami FL AL112024 500 PM AST Fri Sep 27 2024 Deep convection has increased and become more concentrated near the center of Joyce this afternoon. A cold dense overcast has developed and expanded over the low-level center of the tropical cyclone. As a result, the latest satellite intensity estimates have risen, and the initial intensity is brought up to 45 kt. This is consistent with a T3.0/45-kt Dvorak classification from TAFB, as well as a blend of recent UW-CIMSS objective estimates that range from 36-52 kt. Additional near-term strengthening is possible while Joyce remains in an environment of strong upper-level divergence and moderate shear over warm SSTs. However, the storm is forecast to encounter increasing shear and a progressively drier mid-level environment during the next couple of days, which should induce a weakening trend later this weekend and into early next week. The updated NHC intensity forecast peaks at 55 kt in 12 h, with gradual weakening shown thereafter based on the less favorable environmental conditions that are anticipated. Simulated satellite imagery from the latest ECMWF run shows Joyce maintaining organized convection through Monday, but the GFS suggests it could degenerate to a remnant low even sooner. This forecast shows Joyce degenerating into a post-tropical remnant low in 72 h and dissipating by day 5, but future timing changes may be necessary. The storm continues to move northwestward (305/11 kt) around the southwestern periphery of a low- to mid-level ridge over the eastern Atlantic. A slight turn toward the west-northwest is expected during the next day or two, along with a slower forward speed as the steering currents weaken. There is more spread in the track guidance thereafter, with some model disagreement about whether and how quickly the storm turns northward ahead of an upper trough over the central Atlantic. For now, the NHC track forecast is shifted slightly to the left and is a bit slower between 48-72 h, following the latest HCCA and and TVCA trends. FORECAST POSITIONS AND MAX WINDS INIT 27/2100Z 18.6N 44.0W 45 KT 50 MPH 12H 28/0600Z 19.1N 45.3W 55 KT 65 MPH 24H 28/1800Z 19.5N 47.1W 50 KT 60 MPH 36H 29/0600Z 20.1N 48.5W 45 KT 50 MPH 48H 29/1800Z 20.7N 49.5W 40 KT 45 MPH 60H 30/0600Z 21.4N 49.9W 35 KT 40 MPH 72H 30/1800Z 22.0N 49.8W 30 KT 35 MPH...POST-TROP/REMNT LOW 96H 01/1800Z 23.0N 49.5W 30 KT 35 MPH...POST-TROP/REMNT LOW 120H 02/1800Z...DISSIPATED $$ Forecaster Reinhart

Issued at 400 PM CDT Fri Sep 27 2024 367 WTNT44 KNHC 272035 TCDAT4 Post-Tropical Cyclone Helene Discussion Number 18 NWS National Hurricane Center Miami FL AL092024 400 PM CDT Fri Sep 27 2024 Helene has been producing catastrophic flooding over portions of the southeast U.S. and southern Appalachians, and the associated heavy rains are shifting westward into the Ohio and Tennessee Valleys. Satellite images and surface observations indicate that Helene has completed extratropical transition, and the initial intensity is set at 30 kt. The cyclone is moving to the north-northwest at 15 kt. A slowdown is expected tonight, and the cyclone is forecast to stall over the Tennessee Valley this weekend, likely resulting in continued and prolonged rainfall. This is the last tropical cyclone discussion issued by the National Hurricane Center on Helene. Future information on this system can be found in discussions issued by the Weather Prediction Center beginning at 1000 PM CDT, under AWIPS header TCDAT4, WMO header WTNT44 KWNH, and on the web at www.hurricanes.gov. Rainfall forecasts for the United States can always be found at https://www.wpc.ncep.noaa.gov/qpf/qpf2.shtml and outlooks of flash flood risks can be found at https://www.wpc.ncep.noaa.gov/qpf/excessive_rainfall_outlook_ero.php . KEY MESSAGES: 1. Historic, catastrophic and life-threatening flash and urban flooding, including numerous major landslides, will continue across portions of the southern Appalachians through this evening, followed by gradual improvement tonight and into Saturday. Widespread serious river flooding is ongoing, some of which will be major to record breaking. 2. There is a possibility of long-duration power outages in portions of the southeast U.S. If you use a generator, be sure it is placed outside at least 20 feet away from doors, windows, and garages to avoid deadly carbon monoxide poisoning. 3. Use caution after the system passes as deadly hazards remain including downed power lines and flooded areas. FORECAST POSITIONS AND MAX WINDS INIT 27/2100Z 37.5N 85.5W 30 KT 35 MPH...POST-TROPICAL 12H 28/0600Z 37.9N 87.0W 25 KT 30 MPH...POST-TROP/EXTRATROP 24H 28/1800Z 37.7N 87.2W 20 KT 25 MPH...POST-TROP/EXTRATROP 36H 29/0600Z 37.5N 87.3W 20 KT 25 MPH...POST-TROP/EXTRATROP 48H 29/1800Z 37.3N 87.0W 20 KT 25 MPH...POST-TROP/EXTRATROP 60H 30/0600Z...DISSIPATED $$ Forecaster Cangialosi

Issued at 2100 UTC FRI SEP 27 2024 000 FONT14 KNHC 272035 PWSAT4 POST-TROPICAL CYCLONE HELENE WIND SPEED PROBABILITIES NUMBER 18 NWS NATIONAL HURRICANE CENTER MIAMI FL AL092024 2100 UTC FRI SEP 27 2024 AT 2100Z THE CENTER OF POST-TROPICAL CYCLONE HELENE WAS LOCATED NEAR LATITUDE 37.5 NORTH...LONGITUDE 85.5 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 FRI 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 FRI 06Z SAT 18Z SAT 06Z SUN 18Z SUN 18Z MON 18Z TUE PERIODS TO TO TO TO TO TO TO 06Z SAT 18Z SAT 06Z SUN 18Z SUN 18Z MON 18Z TUE 18Z WED FORECAST HOUR (12) (24) (36) (48) (72) (96) (120) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - LOCATION KT $$ FORECASTER CANGIALOSI

...JOYCE BECOMES BETTER ORGANIZED AND STRENGTHENS... As of 5:00 PM AST Fri Sep 27 the center of Joyce was located near 18.6, -44.0 with movement NW at 13 mph. The minimum central pressure was 1001 mb with maximum sustained winds of about 50 mph.

Issued at 500 PM AST Fri Sep 27 2024 510 WTNT31 KNHC 272035 TCPAT1 BULLETIN Tropical Storm Joyce Advisory Number 2 NWS National Hurricane Center Miami FL AL112024 500 PM AST Fri Sep 27 2024 ...JOYCE BECOMES BETTER ORGANIZED AND STRENGTHENS... SUMMARY OF 500 PM AST...2100 UTC...INFORMATION ---------------------------------------------- LOCATION...18.6N 44.0W ABOUT 1250 MI...2015 KM E OF THE NORTHERN LEEWARD ISLANDS MAXIMUM SUSTAINED WINDS...50 MPH...85 KM/H PRESENT MOVEMENT...NW OR 305 DEGREES AT 13 MPH...20 KM/H MINIMUM CENTRAL PRESSURE...1001 MB...29.56 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 Storm Joyce was located near latitude 18.6 North, longitude 44.0 West. Joyce is moving toward the northwest near 13 mph (20 km/h). A west-northwest to northwest motion is expected during the next couple of days, followed by a gradual turn toward the north early next week. Maximum sustained winds have increased to near 50 mph (85 km/h) with higher gusts. Some additional strengthening is possible through early Saturday, followed by gradual weakening through early next week. Tropical-storm-force winds extend outward up to 70 miles (110 km) from the center in the northern semicircle. The estimated minimum central pressure is 1001 mb (29.56 inches). HAZARDS AFFECTING LAND ---------------------- None NEXT ADVISORY ------------- Next complete advisory at 1100 PM AST. $$ Forecaster Reinhart

Issued at 2100 UTC FRI SEP 27 2024 483 FONT11 KNHC 272035 PWSAT1 TROPICAL STORM JOYCE WIND SPEED PROBABILITIES NUMBER 2 NWS NATIONAL HURRICANE CENTER MIAMI FL AL112024 2100 UTC FRI SEP 27 2024 AT 2100Z THE CENTER OF TROPICAL STORM JOYCE WAS LOCATED NEAR LATITUDE 18.6 NORTH...LONGITUDE 44.0 WEST WITH MAXIMUM SUSTAINED WINDS NEAR 45 KTS...50 MPH...85 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 FRI 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 FRI 06Z SAT 18Z SAT 06Z SUN 18Z SUN 18Z MON 18Z TUE PERIODS TO TO TO TO TO TO TO 06Z SAT 18Z SAT 06Z SUN 18Z SUN 18Z MON 18Z TUE 18Z WED FORECAST HOUR (12) (24) (36) (48) (72) (96) (120) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - LOCATION KT $$ FORECASTER REINHART

...HELENE STILL PRODUCING CATASTROPHIC FLOODING OVER PORTIONS OF THE SOUTHERN APPALACHIANS AND TENNESSEE VALLEY... ...FUTURE ADVISORIES WILL BE ISSUED BY THE WEATHER PREDICTION CENTER... As of 4:00 PM CDT Fri Sep 27 the center of Helene was located near 37.5, -85.5 with movement NNW at 17 mph. The minimum central pressure was 984 mb with maximum sustained winds of about 35 mph.

Issued at 400 PM CDT Fri Sep 27 2024 511 WTNT34 KNHC 272035 TCPAT4 BULLETIN Post-Tropical Cyclone Helene Advisory Number 18 NWS National Hurricane Center Miami FL AL092024 400 PM CDT Fri Sep 27 2024 ...HELENE STILL PRODUCING CATASTROPHIC FLOODING OVER PORTIONS OF THE SOUTHERN APPALACHIANS AND TENNESSEE VALLEY... ...FUTURE ADVISORIES WILL BE ISSUED BY THE WEATHER PREDICTION CENTER... SUMMARY OF 400 PM CDT...2100 UTC...INFORMATION ---------------------------------------------- LOCATION...37.5N 85.5W ABOUT 50 MI...80 KM SSE OF LOUISVILLE KENTUCKY MAXIMUM SUSTAINED WINDS...35 MPH...55 KM/H PRESENT MOVEMENT...NNW OR 330 DEGREES AT 17 MPH...28 KM/H MINIMUM CENTRAL PRESSURE...984 MB...29.06 INCHES WATCHES AND WARNINGS -------------------- There are no coastal watches or warnings in effect. For storm information specific to your area, please monitor products issued by your local National Weather Service forecast office. DISCUSSION AND OUTLOOK ---------------------- At 400 PM CDT (2100 UTC), the center of Post-Tropical Cyclone Helene was located near latitude 37.5 North, longitude 85.5 West. The post-tropical cyclone is moving toward the north-northwest near 17 mph (28 km/h). A slowdown in forward speed is expected, and the system is forecast to stall over the Tennessee Valley late tonight and through the weekend. Maximum sustained winds are near 35 mph (55 km/h) with higher gusts. Continued weakening is expected during the next couple of days. The estimated minimum central pressure is 984 mb (29.06 inches). HAZARDS AFFECTING LAND ---------------------- Key Messages for Helene can be found in the Tropical Cyclone Discussion under AWIPS header MIATCDAT4 and WMO header WTNT44 KNHC and on the web at hurricanes.gov/text/MIATCDAT4.shtml RAINFALL: Over portions of the central and southern Appalachians, Helene is expected to produce additional rainfall amounts of 1 to 2 inches leading to widespread total rainfall accumulations of 6 to 12 inches, with isolated totals exceeding 20 inches. This rainfall will result in catastrophic and potentially life-threatening flash and urban flooding, along with record level river flooding in many instances. Numerous significant landslides are expected in steep terrain across the southern Appalachians. Elsewhere, 1 to 3 inches of rainfall is expected across portions of the Ohio Valley through Sunday evening. For a complete depiction of forecast rainfall associated with Tropical Storm Helene, please see the National Weather Service Storm Total Rainfall Graphic, available at hurricanes.gov/graphics_at4.shtml?rainqpf and the Flash Flood Risk graphic at hurricanes.gov/graphics_at4.shtml?ero. For a list of rainfall observations (and wind reports) associated this storm, see the companion storm summary at WBCSCCNS4 with the WMO header ACUS44 KWBC or at the following link: www.wpc.ncep.noaa.gov/discussions/nfdscc4.html. TORNADOES: Isolated tornadoes are possible this afternoon and evening over southern Virginia and northeast North Carolina. SURF: Swells generated by Helene will affect the coasts of Georgia and the Carolinas during the next day or so. These swells are likely to cause life-threatening surf and rip current conditions. Please consult products from your local weather office. NEXT ADVISORY ------------- This is the last public advisory issued by the National Hurricane Center on Helene. Future information on this system can be found in Public Advisories issued by the Weather Prediction Center beginning at 1000 PM CDT, under AWIPS header TCPAT4, WMO header WTNT34 KWNH, and on the web at www.hurricanes.gov. Rainfall forecasts for the United States can always be found at https://www.wpc.ncep.noaa.gov/qpf/qpf2.shtml and outlooks of flash flood risks can be found at https://www.wpc.ncep.noaa.gov/qpf/excessive_rainfall_outlook_ero.php . $$ Forecaster Cangialosi

Issued at 2100 UTC FRI SEP 27 2024 538 WTNT21 KNHC 272034 TCMAT1 TROPICAL STORM JOYCE FORECAST/ADVISORY NUMBER 2 NWS NATIONAL HURRICANE CENTER MIAMI FL AL112024 2100 UTC FRI SEP 27 2024 TROPICAL STORM CENTER LOCATED NEAR 18.6N 44.0W AT 27/2100Z POSITION ACCURATE WITHIN 30 NM PRESENT MOVEMENT TOWARD THE NORTHWEST OR 305 DEGREES AT 11 KT ESTIMATED MINIMUM CENTRAL PRESSURE 1001 MB MAX SUSTAINED WINDS 45 KT WITH GUSTS TO 55 KT. 34 KT....... 60NE 0SE 0SW 60NW. 12 FT SEAS.. 45NE 0SE 0SW 45NW. 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 18.6N 44.0W AT 27/2100Z AT 27/1800Z CENTER WAS LOCATED NEAR 18.3N 43.5W FORECAST VALID 28/0600Z 19.1N 45.3W MAX WIND 55 KT...GUSTS 65 KT. 50 KT... 20NE 0SE 0SW 0NW. 34 KT... 80NE 30SE 10SW 70NW. FORECAST VALID 28/1800Z 19.5N 47.1W MAX WIND 50 KT...GUSTS 60 KT. 50 KT... 20NE 0SE 0SW 0NW. 34 KT... 80NE 30SE 20SW 60NW. FORECAST VALID 29/0600Z 20.1N 48.5W MAX WIND 45 KT...GUSTS 55 KT. 34 KT... 60NE 20SE 20SW 40NW. FORECAST VALID 29/1800Z 20.7N 49.5W MAX WIND 40 KT...GUSTS 50 KT. 34 KT... 50NE 20SE 0SW 30NW. FORECAST VALID 30/0600Z 21.4N 49.9W MAX WIND 35 KT...GUSTS 45 KT. 34 KT... 40NE 20SE 0SW 20NW. FORECAST VALID 30/1800Z 22.0N 49.8W...POST-TROP/REMNT LOW MAX WIND 30 KT...GUSTS 40 KT. EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 125 NM ON DAY 4 AND 175 NM ON DAY 5...AND FOR INTENSITY NEAR 15 KT EACH DAY OUTLOOK VALID 01/1800Z 23.0N 49.5W...POST-TROP/REMNT LOW MAX WIND 30 KT...GUSTS 40 KT. OUTLOOK VALID 02/1800Z...DISSIPATED REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 18.6N 44.0W NEXT ADVISORY AT 28/0300Z $$ FORECASTER REINHART