NHC Atlantic

Atlantic Tropical Weather Outlook

nhcwebmaster@noaa.gov (NHC Webmaster) — Sun, 05 Sep 2021 17:47:03 GMT

000
ABNT20 KNHC 051746
TWOAT

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
200 PM EDT Sun Sep 5 2021

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

The National Hurricane Center is issuing advisories on Hurricane
Larry, located over the central tropical Atlantic about 900 miles
east of the northern Leeward Islands.

Disorganized showers and thunderstorms over the Yucatan Peninsula
and surrounding waters are associated with a surface trough and an
upper-level disturbance. Locally heavy rains are likely to continue
today over that area. The system is forecast to move slowly
northward or northeastward over the central and then northeastern
Gulf of Mexico over the next few days, when upper-level winds are
only expected to be marginally conducive for tropical cyclone
formation. The disturbance is then expected to cross the
southeastern United States beginning midweek, and some development
is possible once it emerges over the Atlantic waters by late this
week.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 5 days...low...30 percent.

$$
Forecaster Latto

Summary for Hurricane Larry (AT2/AL122021)

nhcwebmaster@noaa.gov (NHC Webmaster) — Sun, 05 Sep 2021 14:44:58 GMT

...LARRY EXPECTED TO CAUSE DANGEROUS SURF AND RIP CURRENTS ALONG THE WESTERN ATLANTIC SHORES LATER THIS WEEK... As of 11:00 AM AST Sun Sep 5 the center of Larry was located near 19.5, -49.7 with movement NW at 13 mph. The minimum central pressure was 955 mb with maximum sustained winds of about 125 mph.

Hurricane Larry Public Advisory Number 20

nhcwebmaster@noaa.gov (NHC Webmaster) — Sun, 05 Sep 2021 14:44:58 GMT

Issued at 1100 AM AST Sun Sep 05 2021 000 WTNT32 KNHC 051444 TCPAT2 BULLETIN Hurricane Larry Advisory Number 20 NWS National Hurricane Center Miami FL AL122021 1100 AM AST Sun Sep 05 2021 ...LARRY EXPECTED TO CAUSE DANGEROUS SURF AND RIP CURRENTS ALONG THE WESTERN ATLANTIC SHORES LATER THIS WEEK... SUMMARY OF 1100 AM AST...1500 UTC...INFORMATION ----------------------------------------------- LOCATION...19.5N 49.7W ABOUT 880 MI...1415 KM E OF THE NORTHERN LEEWARD ISLANDS ABOUT 1285 MI...2070 KM SE OF BERMUDA MAXIMUM SUSTAINED WINDS...125 MPH...205 KM/H PRESENT MOVEMENT...NW OR 310 DEGREES AT 13 MPH...20 KM/H MINIMUM CENTRAL PRESSURE...955 MB...28.20 INCHES WATCHES AND WARNINGS -------------------- There are no coastal watches or warnings in effect. DISCUSSION AND OUTLOOK ---------------------- At 1100 AM AST (1500 UTC), the eye of Hurricane Larry was located near latitude 19.5 North, longitude 49.7 West. Larry is moving toward the northwest near 13 mph (20 km/h). A northwestward motion with a slight decrease in forward speed is expected during the next few days. Maximum sustained winds are near 125 mph (205 km/h) with higher gusts. Larry is a category 3 hurricane on the Saffir-Simpson Hurricane Wind Scale. Little change in strength is forecast during the next few days, although fluctuations in intensity will be possible. Larry is expected to remain a major hurricane through the middle of this week. Larry is a large hurricane. Hurricane-force winds extend outward up to 45 miles (75 km) from the center and tropical-storm-force winds extend outward up to 175 miles (280 km). The estimated minimum central pressure is 955 mb (28.20 inches). HAZARDS AFFECTING LAND ---------------------- SURF: Swells generated by Larry are expected to reach the Lesser Antilles today, and will spread westward to portions of the Greater Antilles, the Bahamas, and Bermuda on Monday and Tuesday. Significant swells will likely reach the east coast of the United States and Atlantic Canada by midweek. 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 500 PM AST. $$ Forecaster Pasch ]]>

Hurricane Larry Forecast Advisory Number 21

nhcwebmaster@noaa.gov (NHC Webmaster) — Sun, 05 Sep 2021 20:47:38 GMT

Issued at 2100 UTC SUN SEP 05 2021 668 WTNT22 KNHC 052047 TCMAT2 HURRICANE LARRY FORECAST/ADVISORY NUMBER 21 NWS NATIONAL HURRICANE CENTER MIAMI FL AL122021 2100 UTC SUN SEP 05 2021 THERE ARE NO COASTAL WATCHES OR WARNINGS IN EFFECT. HURRICANE CENTER LOCATED NEAR 20.5N 50.6W AT 05/2100Z POSITION ACCURATE WITHIN 15 NM PRESENT MOVEMENT TOWARD THE NORTHWEST OR 315 DEGREES AT 11 KT ESTIMATED MINIMUM CENTRAL PRESSURE 955 MB MAX SUSTAINED WINDS 110 KT WITH GUSTS TO 135 KT. 64 KT....... 40NE 30SE 25SW 35NW. 50 KT....... 80NE 80SE 40SW 70NW. 34 KT.......140NE 150SE 70SW 130NW. 12 FT SEAS..300NE 210SE 240SW 300NW. 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 20.5N 50.6W AT 05/2100Z AT 05/1800Z CENTER WAS LOCATED NEAR 20.1N 50.2W FORECAST VALID 06/0600Z 21.6N 51.9W MAX WIND 110 KT...GUSTS 135 KT. 64 KT... 50NE 40SE 30SW 40NW. 50 KT... 80NE 80SE 50SW 70NW. 34 KT...150NE 150SE 80SW 130NW. FORECAST VALID 06/1800Z 22.7N 53.4W MAX WIND 110 KT...GUSTS 135 KT. 64 KT... 50NE 40SE 35SW 50NW. 50 KT... 80NE 80SE 50SW 70NW. 34 KT...150NE 150SE 90SW 130NW. FORECAST VALID 07/0600Z 23.9N 54.8W MAX WIND 105 KT...GUSTS 130 KT. 64 KT... 60NE 50SE 40SW 50NW. 50 KT... 90NE 80SE 60SW 80NW. 34 KT...150NE 150SE 100SW 130NW. FORECAST VALID 07/1800Z 25.3N 56.2W MAX WIND 100 KT...GUSTS 120 KT. 64 KT... 60NE 50SE 40SW 50NW. 50 KT...100NE 90SE 70SW 80NW. 34 KT...160NE 150SE 110SW 130NW. FORECAST VALID 08/0600Z 26.8N 57.5W MAX WIND 100 KT...GUSTS 120 KT. 50 KT...100NE 90SE 70SW 80NW. 34 KT...170NE 170SE 120SW 140NW. FORECAST VALID 08/1800Z 28.5N 59.1W MAX WIND 100 KT...GUSTS 120 KT. 50 KT...100NE 90SE 70SW 90NW. 34 KT...180NE 170SE 130SW 150NW. EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 150 NM ON DAY 4 AND 175 NM ON DAY 5...AND FOR INTENSITY NEAR 15 KT EACH DAY OUTLOOK VALID 09/1800Z 32.8N 61.3W MAX WIND 95 KT...GUSTS 115 KT. OUTLOOK VALID 10/1800Z 39.8N 58.7W MAX WIND 85 KT...GUSTS 105 KT. REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 20.5N 50.6W NEXT ADVISORY AT 06/0300Z $$ FORECASTER LATTO ]]>

Hurricane Larry Forecast Discussion Number 20

nhcwebmaster@noaa.gov (NHC Webmaster) — Sun, 05 Sep 2021 14:45:32 GMT

Issued at 1100 AM AST Sun Sep 05 2021 000 WTNT42 KNHC 051445 TCDAT2 Hurricane Larry Discussion Number 20 NWS National Hurricane Center Miami FL AL122021 1100 AM AST Sun Sep 05 2021 Larry continues as a large and intense hurricane this morning, with a 40 n mi diameter eye surround by cloud tops to near -80 deg C. There are, however, some breaks in the cold tops over the northern portion of the circulation. The current intensity is adjusted slightly to 110 kt, based on a blend of subjective Dvorak estimates from TAFB and SAB along with objective ADT estimates from UW-CIMSS. Upper-level outflow remains somewhat restricted over the southwestern quadrant of the system, indicative of at least slight vertical shear. This shear is probably being caused by the flow to the east of an upper-level low to the north of Puerto Rico. The low is forecast to move northwestward over the next few days, possibly lessening the shear over Larry. The hurricane is moving northwestward at a slightly slower speed, or 310/11 kt. Larry is likely to continue its northwestward trek along the southwestern periphery of a mid-tropospheric anticyclone during the next 2-3 days, with only a slight reduction in forward speed. Around 96 hours, the hurricane is forecast to turn toward the north-northwest and north while rounding the western side of the ridge. By the end of the forecast period, Larry is expected to begin its recurvature into the mid-latitude westerlies. The new official forecast track essentially follows the previous one, and is also very close to the latest NOAA corrected consensus and Florida State University Superensemble guidance. Larry's large eye suggests that no rapid changes in strength are likely during the short term. Since vertical shear is not expected to increase and the system will be traversing warm waters, the hurricane should be able to more or less maintain its intensity during the next few days. One inhibiting factor is the presence of relatively dry mid-level air in the environment. The official intensity forecast is on the high side of the model guidance and keeps Larry as a major hurricane through 72 hours. Key Messages: 1. Large swells generated by Larry are expected to reach the Lesser Antilles today and will spread to portions of the Greater Antilles, the Bahamas, and Bermuda on Monday and Tuesday. Significant swells will likely reach the east coast of the United States and Atlantic Canada by midweek. These swells will likely cause life-threatening surf and rip current conditions, and beachgoers and other interests along these coasts are urged to follow the advice of lifeguards and local officials this week. 2. Larry is forecast to approach Bermuda during the next several days, likely as a major hurricane, bringing a risk of strong winds, heavy rainfall, and coastal flooding to the island by the middle of this week. While it is too soon to determine the magnitude of these hazards and potential impacts on Bermuda, interests there should closely monitor the latest forecast updates during the next several days. FORECAST POSITIONS AND MAX WINDS INIT 05/1500Z 19.5N 49.7W 110 KT 125 MPH 12H 06/0000Z 20.5N 51.1W 110 KT 125 MPH 24H 06/1200Z 21.9N 52.7W 110 KT 125 MPH 36H 07/0000Z 23.0N 54.0W 110 KT 125 MPH 48H 07/1200Z 24.3N 55.4W 105 KT 120 MPH 60H 08/0000Z 25.7N 56.7W 105 KT 120 MPH 72H 08/1200Z 27.3N 58.1W 105 KT 120 MPH 96H 09/1200Z 31.1N 61.1W 95 KT 110 MPH 120H 10/1200Z 37.4N 60.6W 85 KT 100 MPH $$ Forecaster Pasch ]]>

Hurricane Larry Wind Speed Probabilities Number 20

nhcwebmaster@noaa.gov (NHC Webmaster) — Sun, 05 Sep 2021 14:45:01 GMT

Issued at 1500 UTC SUN SEP 05 2021 000 FONT12 KNHC 051444 PWSAT2 HURRICANE LARRY WIND SPEED PROBABILITIES NUMBER 20 NWS NATIONAL HURRICANE CENTER MIAMI FL AL122021 1500 UTC SUN SEP 05 2021 AT 1500Z THE CENTER OF HURRICANE LARRY WAS LOCATED NEAR LATITUDE 19.5 NORTH...LONGITUDE 49.7 WEST WITH MAXIMUM SUSTAINED WINDS NEAR 110 KTS...125 MPH...205 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 12Z SUN AND THE FORECAST HOUR (CUMULATIVE PROBABILITY) PROBABILITIES ARE GIVEN IN PERCENT X INDICATES PROBABILITIES LESS THAN 1 PERCENT PROBABILITIES FOR 34 KT AND 50 KT ARE SHOWN AT A GIVEN LOCATION WHEN THE 5-DAY CUMULATIVE PROBABILITY IS AT LEAST 3 PERCENT. PROBABILITIES FOR 34...50...64 KT SHOWN WHEN THE 5-DAY 64-KT CUMULATIVE PROBABILITY IS AT LEAST 1 PERCENT. - - - - WIND SPEED PROBABILITIES FOR SELECTED LOCATIONS - - - - FROM FROM FROM FROM FROM FROM FROM TIME 12Z SUN 00Z MON 12Z MON 00Z TUE 12Z TUE 12Z WED 12Z THU PERIODS TO TO TO TO TO TO TO 00Z MON 12Z MON 00Z TUE 12Z TUE 12Z WED 12Z THU 12Z FRI FORECAST HOUR (12) (24) (36) (48) (72) (96) (120) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - LOCATION KT SABLE ISLAND 34 X X( X) X( X) X( X) X( X) X( X) 8( 8) HALIFAX NS 34 X X( X) X( X) X( X) X( X) X( X) 3( 3) BERMUDA 34 X X( X) X( X) X( X) X( X) 23(23) 12(35) BERMUDA 50 X X( X) X( X) X( X) X( X) 7( 7) 5(12) BERMUDA 64 X X( X) X( X) X( X) X( X) 3( 3) 3( 6) $$ FORECASTER PASCH ]]>

Hurricane Larry Graphics

nhcwebmaster@noaa.gov (NHC Webmaster) — Sun, 05 Sep 2021 14:47:54 GMT

5-Day Uncertainty Track last updated Sun, 05 Sep 2021 14:47:54 GMT

Wind Speed Probabilities last updated Sun, 05 Sep 2021 15:22:48 GMT