National Hurricane Center (NHC) Atlantic Map

Issued at 1500 UTC MON OCT 04 2021 000 FONT15 KNHC 041442 PWSAT5 REMNANTS OF VICTOR WIND SPEED PROBABILITIES NUMBER 21 NWS NATIONAL HURRICANE CENTER MIAMI FL AL202021 1500 UTC MON OCT 04 2021 AT 1500Z THE REMNANTS OF VICTOR WERE LOCATED NEAR LATITUDE 18.8 NORTH...LONGITUDE 45.2 WEST WITH MAXIMUM SUSTAINED WINDS NEAR 25 KTS ...30 MPH...45 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 MON 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 MON 00Z TUE 12Z TUE 00Z WED 12Z WED 12Z THU 12Z FRI PERIODS TO TO TO TO TO TO TO 00Z TUE 12Z TUE 00Z WED 12Z WED 12Z THU 12Z FRI 12Z SAT FORECAST HOUR (12) (24) (36) (48) (72) (96) (120) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - LOCATION KT ...THERE IS NO OFFICIAL FORECAST FOR THIS DATE/TIME... AND THEREFORE NO WIND SPEED PROBABILITIES CAN BE CALCULATED... $$ FORECASTER REINHART

Issued at 1100 AM AST Mon Oct 04 2021 000 WTNT35 KNHC 041442 TCPAT5 BULLETIN Remnants Of Victor Advisory Number 21 NWS National Hurricane Center Miami FL AL202021 1100 AM AST Mon Oct 04 2021 ...VICTOR DEGENERATES INTO A TROUGH OVER THE CENTRAL ATLANTIC... ...THIS IS THE FINAL NHC ADVISORY... SUMMARY OF 1100 AM AST...1500 UTC...INFORMATION ----------------------------------------------- LOCATION...18.8N 45.2W ABOUT 1410 MI...2270 KM W OF THE CABO VERDE ISLANDS MAXIMUM SUSTAINED WINDS...30 MPH...45 KM/H PRESENT MOVEMENT...WNW OR 300 DEGREES AT 15 MPH...24 KM/H MINIMUM CENTRAL PRESSURE...1011 MB...29.86 INCHES WATCHES AND WARNINGS -------------------- There are no coastal watches or warnings in effect. DISCUSSION AND OUTLOOK ---------------------- At 1100 AM AST (1500 UTC), the remnants of Victor were located near latitude 18.8 North, longitude 45.2 West. The remnants are moving toward the west-northwest near 15 mph (24 km/h), and this general motion is expected to continue through tonight. Recent satellite-derived wind data indicate that maximum sustained winds are near 30 mph (45 km/h) with higher gusts. Weakening is forecast through tonight. The estimated minimum central pressure is 1011 mb (29.86 inches). HAZARDS AFFECTING LAND ---------------------- None. NEXT ADVISORY ------------- This is the last public advisory issued by the National Hurricane Center on Victor. Additional information on the remnants of Victor can be found in High Seas Forecasts issued by the National Weather Service, under AWIPS header NFDHSFAT1, WMO header FZNT01 KWBC, and online at ocean.weather.gov/shtml/NFDHSFAT1.php $$ Forecaster Reinhart

...VICTOR DEGENERATES INTO A TROUGH OVER THE CENTRAL ATLANTIC... ...THIS IS THE FINAL NHC ADVISORY... As of 11:00 AM AST Mon Oct 4 the center of Victor was located near 18.8, -45.2 with movement WNW at 15 mph. The minimum central pressure was 1011 mb with maximum sustained winds of about 30 mph.

Issued at 1500 UTC MON OCT 04 2021 000 FONT13 KNHC 041442 PWSAT3 HURRICANE SAM WIND SPEED PROBABILITIES NUMBER 48 NWS NATIONAL HURRICANE CENTER MIAMI FL AL182021 1500 UTC MON OCT 04 2021 AT 1500Z THE CENTER OF HURRICANE SAM WAS LOCATED NEAR LATITUDE 42.6 NORTH...LONGITUDE 45.7 WEST WITH MAXIMUM SUSTAINED WINDS NEAR 85 KTS ...100 MPH...155 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 MON 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 MON 00Z TUE 12Z TUE 00Z WED 12Z WED 12Z THU 12Z FRI PERIODS TO TO TO TO TO TO TO 00Z TUE 12Z TUE 00Z WED 12Z WED 12Z THU 12Z FRI 12Z SAT FORECAST HOUR (12) (24) (36) (48) (72) (96) (120) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - LOCATION KT HIBERNIA OILFD 34 5 3( 8) X( 8) X( 8) X( 8) X( 8) X( 8) $$ FORECASTER BROWN

Issued at 1500 UTC MON OCT 04 2021 000 WTNT25 KNHC 041442 TCMAT5 REMNANTS OF VICTOR FORECAST/ADVISORY NUMBER 21 NWS NATIONAL HURRICANE CENTER MIAMI FL AL202021 1500 UTC MON OCT 04 2021 THERE ARE NO COASTAL WATCHES OR WARNINGS IN EFFECT. REMNANTS OF CENTER LOCATED NEAR 18.8N 45.2W AT 04/1500Z POSITION ACCURATE WITHIN 40 NM PRESENT MOVEMENT TOWARD THE WEST-NORTHWEST OR 300 DEGREES AT 13 KT ESTIMATED MINIMUM CENTRAL PRESSURE 1011 MB MAX SUSTAINED WINDS 25 KT WITH GUSTS TO 35 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 18.8N 45.2W AT 04/1500Z AT 04/1200Z CENTER WAS LOCATED NEAR 18.5N 44.5W FORECAST VALID 05/0000Z...DISSIPATED REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 18.8N 45.2W THIS IS THE LAST FORECAST/ADVISORY ISSUED BY THE NATIONAL HURRICANE CENTER ON VICTOR. ADDITIONAL INFORMATION ON THE REMNANTS OF VICTOR CAN BE FOUND IN HIGH SEAS FORECASTS ISSUED BY THE NATIONAL WEATHER SERVICE...UNDER AWIPS HEADER NFDHSFAT1 AND WMO HEADER FZNT01 KWBC. $$ FORECASTER REINHART

Issued at 1100 AM AST Mon Oct 04 2021 000 WTNT33 KNHC 041442 TCPAT3 BULLETIN Hurricane Sam Advisory Number 48 NWS National Hurricane Center Miami FL AL182021 1100 AM AST Mon Oct 04 2021 ...SAM MOVING QUICKLY NORTHEASTWARD... ...FORECAST TO BECOME A POWERFUL POST-TROPICAL CYCLONE TONIGHT OR EARLY TUESDAY... SUMMARY OF 1100 AM AST...1500 UTC...INFORMATION ----------------------------------------------- LOCATION...42.6N 45.7W ABOUT 460 MI...740 KM SE OF CAPE RACE NEWFOUNDLAND MAXIMUM SUSTAINED WINDS...100 MPH...155 KM/H PRESENT MOVEMENT...NE OR 45 DEGREES AT 32 MPH...52 KM/H MINIMUM CENTRAL PRESSURE...960 MB...28.35 INCHES WATCHES AND WARNINGS -------------------- There are no coastal watches or warnings in effect. DISCUSSION AND OUTLOOK ---------------------- At 1100 AM AST (1500 UTC), the center of Hurricane Sam was located near latitude 42.6 North, longitude 45.7 West. Sam is moving toward the northeast near 32 mph (52 km/h). A faster northeastward motion is expected through tonight. A slower east-northeastward motion is forecast to begin on Tuesday and continue through midweek. Maximum sustained winds are near 100 mph (155 km/h) with higher gusts. Gradual weakening is forecast during the next few days, and Sam is expected to transition into a powerful post-tropical cyclone over the north Atlantic tonight or early Tuesday. 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 ---------------------- Key messages for Sam can be found in the Tropical Cyclone Discussion under AWIPS header MIATCDAT3 and WMO header WTNT43 KNHC, and on the web at hurricanes.gov/graphics_at3.shtml?key_messages. SURF: Swells generated by Sam will impact the northern Leeward Islands, the Greater Antilles, portions of the Bahamas, and southeastern Newfoundland for the next day or so. These swells could 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 Brown

...SAM MOVING QUICKLY NORTHEASTWARD... ...FORECAST TO BECOME A POWERFUL POST-TROPICAL CYCLONE TONIGHT OR EARLY TUESDAY... As of 11:00 AM AST Mon Oct 4 the center of Sam was located near 42.6, -45.7 with movement NE at 32 mph. The minimum central pressure was 960 mb with maximum sustained winds of about 100 mph.

Issued at 1500 UTC MON OCT 04 2021 000 WTNT23 KNHC 041441 TCMAT3 HURRICANE SAM FORECAST/ADVISORY NUMBER 48 NWS NATIONAL HURRICANE CENTER MIAMI FL AL182021 1500 UTC MON OCT 04 2021 THERE ARE NO COASTAL WATCHES OR WARNINGS IN EFFECT. HURRICANE CENTER LOCATED NEAR 42.6N 45.7W AT 04/1500Z POSITION ACCURATE WITHIN 25 NM PRESENT MOVEMENT TOWARD THE NORTHEAST OR 45 DEGREES AT 28 KT ESTIMATED MINIMUM CENTRAL PRESSURE 960 MB MAX SUSTAINED WINDS 85 KT WITH GUSTS TO 105 KT. 64 KT....... 0NE 50SE 50SW 0NW. 50 KT.......100NE 100SE 100SW 70NW. 34 KT.......220NE 240SE 240SW 220NW. 12 FT SEAS..350NE 390SE 580SW 330NW. 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 42.6N 45.7W AT 04/1500Z AT 04/1200Z CENTER WAS LOCATED NEAR 41.4N 47.1W FORECAST VALID 05/0000Z 46.5N 41.9W MAX WIND 75 KT...GUSTS 90 KT. 64 KT... 40NE 60SE 60SW 0NW. 50 KT...110NE 140SE 140SW 70NW. 34 KT...240NE 300SE 300SW 270NW. FORECAST VALID 05/1200Z 50.0N 40.5W...POST-TROP/EXTRATROP MAX WIND 70 KT...GUSTS 85 KT. 64 KT... 40NE 60SE 60SW 40NW. 50 KT...110NE 180SE 180SW 70NW. 34 KT...270NE 420SE 420SW 330NW. FORECAST VALID 06/0000Z 50.3N 38.3W...POST-TROP/EXTRATROP MAX WIND 60 KT...GUSTS 75 KT. 50 KT... 60NE 150SE 150SW 60NW. 34 KT...270NE 420SE 420SW 330NW. FORECAST VALID 06/1200Z 51.4N 33.2W...POST-TROP/EXTRATROP MAX WIND 55 KT...GUSTS 65 KT. 50 KT... 0NE 120SE 120SW 0NW. 34 KT...240NE 330SE 330SW 240NW. FORECAST VALID 07/0000Z 54.3N 27.7W...POST-TROP/EXTRATROP MAX WIND 50 KT...GUSTS 60 KT. 50 KT... 0NE 100SE 0SW 0NW. 34 KT...210NE 270SE 270SW 180NW. FORECAST VALID 07/1200Z 58.3N 24.8W...POST-TROP/EXTRATROP MAX WIND 50 KT...GUSTS 60 KT. 50 KT... 0NE 100SE 0SW 0NW. 34 KT...360NE 240SE 210SW 450NW. 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 08/1200Z 61.0N 29.7W...POST-TROP/EXTRATROP MAX WIND 50 KT...GUSTS 60 KT. OUTLOOK VALID 09/1200Z 60.0N 29.8W...POST-TROP/EXTRATROP MAX WIND 40 KT...GUSTS 50 KT. REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 42.6N 45.7W NEXT ADVISORY AT 04/2100Z $$ FORECASTER BROWN

000
ABNT20 KNHC 041116
TWOAT

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
800 AM EDT Mon Oct 4 2021

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

The National Hurricane Center is issuing advisories on Hurricane
Sam, located over the far North Atlantic, and on Tropical
Depression Victor, located over the central tropical Atlantic.

A large area of disorganized cloudiness and showers continues over
the southeastern Bahamas and adjacent southwestern Atlantic waters
in association with a surface trough. Upper-level winds are not
expected to be especially conducive, and any development of this
system should be slow to occur while it moves slowly northwestward
through the end of this week.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 5 days...low...10 percent.

$$
Forecaster Brown

5-Day Uncertainty Track last updated Mon, 27 Sep 2021 15:00:56 GMT


Wind Speed Probabilities last updated Mon, 27 Sep 2021 15:22:52 GMT

Issued at 1100 AM AST Mon Sep 27 2021 759 WTNT43 KNHC 271459 TCDAT3 Hurricane Sam Discussion Number 20 NWS National Hurricane Center Miami FL AL182021 1100 AM AST Mon Sep 27 2021 Sam appeared weaker on satellite images earlier this morning, and the eye was not apparent in visible or infrared satellite imagery. However, a 27/0741 UTC SSMIS pass still showed a well-defined eye. Recent visible and infrared images from the past couple of hours however, show that the structure is becoming better organized again, with the eye again becoming apparent on visible satellite. A NOAA Hurricane Hunter aircraft has made one pass through the hurricane so far and found that the central pressure has risen to about 966 mb. The current intensity estimate is reduced slightly to 110 kt. The aircraft has not yet sampled the northeast quadrant, where the strongest winds are likely occurring. The initial motion is estimated to be northwestward, or 310/7. A subtropical ridge to the north and northeast of Sam will remain the primary steering mechanism over the next several days, and Sam is expected to continue on a similar heading through the next 72 hours or so. A mid- to upper-level trough is forecast to emerge off the U.S. Northeast and Mid-Atlantic coast and dig southward over the western Atlantic late this week. The deep-layer southerly flow ahead of this feature should cause Sam to accelerate to the north-northwest by late Thursday and then turn northward on Friday. The NHC forecast track is largely unchanged from the previous, except it is shifted ever so slightly westward at the hour 72 and 96 points, about midway between the previous NHC forecast and the latest HCCA consensus. The confidence in the track forecast is medium to high through 3 to 4 days. Beyond that time, confidence is about average, as there is some increase in model spread noted. Regarding the intensity forecast, Sam is forecast to travel over warm ocean temperatures while it remains in an environment of low vertical wind shear through the next 4 days. Some mid-level dry air noted on water vapor channels to the west of Sam could play a role in limiting Sam's intensity through hour 48. However, the environment could become more moist again after that time. Due to these competing factors, I opted to hold the intensity steady for the next several days, although fluctuations in intensity can be expected. The NHC intensity forecast is above all model guidance through hour 60, and is in agreement with the model consensus at hour 72-96. After that time, increasing wind shear induced by the approaching mid- to upper-level trough to the northwest of the cyclone should cause weakening. FORECAST POSITIONS AND MAX WINDS INIT 27/1500Z 15.7N 52.1W 110 KT 125 MPH 12H 28/0000Z 16.4N 52.8W 110 KT 125 MPH 24H 28/1200Z 17.3N 53.9W 110 KT 125 MPH 36H 29/0000Z 18.1N 55.1W 110 KT 125 MPH 48H 29/1200Z 19.1N 56.5W 110 KT 125 MPH 60H 30/0000Z 20.2N 58.1W 110 KT 125 MPH 72H 30/1200Z 21.7N 59.8W 110 KT 125 MPH 96H 01/1200Z 25.9N 62.2W 110 KT 125 MPH 120H 02/1200Z 32.0N 61.3W 100 KT 115 MPH $$ Forecaster Hagen/Pasch

Issued at 1500 UTC MON SEP 27 2021 940 FONT13 KNHC 271454 PWSAT3 HURRICANE SAM WIND SPEED PROBABILITIES NUMBER 20 NWS NATIONAL HURRICANE CENTER MIAMI FL AL182021 1500 UTC MON SEP 27 2021 AT 1500Z THE CENTER OF HURRICANE SAM WAS LOCATED NEAR LATITUDE 15.7 NORTH...LONGITUDE 52.1 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 MON 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 MON 00Z TUE 12Z TUE 00Z WED 12Z WED 12Z THU 12Z FRI PERIODS TO TO TO TO TO TO TO 00Z TUE 12Z TUE 00Z WED 12Z WED 12Z THU 12Z FRI 12Z SAT FORECAST HOUR (12) (24) (36) (48) (72) (96) (120) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - LOCATION KT BERMUDA 34 X X( X) X( X) X( X) X( X) 3( 3) 26(29) BERMUDA 50 X X( X) X( X) X( X) X( X) 1( 1) 11(12) BERMUDA 64 X X( X) X( X) X( X) X( X) X( X) 7( 7) SAINT THOMAS 34 X X( X) X( X) X( X) 1( 1) 2( 3) X( 3) SAINT MAARTEN 34 X X( X) X( X) X( X) 4( 4) 2( 6) X( 6) SABA 34 X X( X) X( X) X( X) 2( 2) 1( 3) X( 3) ST EUSTATIUS 34 X X( X) X( X) X( X) 3( 3) X( 3) 1( 4) ST KITTS-NEVIS 34 X X( X) X( X) X( X) 3( 3) 1( 4) X( 4) BARBUDA 34 X X( X) X( X) 1( 1) 5( 6) 2( 8) X( 8) ANTIGUA 34 X X( X) X( X) 1( 1) 4( 5) 1( 6) X( 6) GUADELOUPE 34 X X( X) X( X) 1( 1) 2( 3) 1( 4) X( 4) $$ FORECASTER HAGEN/PASCH

Issued at 1100 AM AST Mon Sep 27 2021 769 WTNT33 KNHC 271453 TCPAT3 BULLETIN Hurricane Sam Advisory Number 20 NWS National Hurricane Center Miami FL AL182021 1100 AM AST Mon Sep 27 2021 ...HURRICANE HUNTER AIRCRAFT CURRENTLY INVESTIGATING SAM... SUMMARY OF 1100 AM AST...1500 UTC...INFORMATION ----------------------------------------------- LOCATION...15.7N 52.1W ABOUT 745 MI...1200 KM ESE OF THE NORTHERN LEEWARD ISLANDS MAXIMUM SUSTAINED WINDS...125 MPH...205 KM/H PRESENT MOVEMENT...NW OR 310 DEGREES AT 8 MPH...13 KM/H MINIMUM CENTRAL PRESSURE...966 MB...28.53 INCHES WATCHES AND WARNINGS -------------------- There are no coastal watches or warnings in effect. DISCUSSION AND OUTLOOK ---------------------- At 1100 AM AST (1500 UTC), the center of Hurricane Sam was located near latitude 15.6 North, longitude 52.0 West. Sam is moving toward the northwest near 8 mph (13 km/h) and this motion is expected to continue for the next few days, with an increase in forward speed beginning on Thursday. A turn to the north is expected on Friday. On the forecast track, Sam will pass well to the northeast of the northern Leeward Islands Wednesday and Thursday. Maximum sustained winds are near 125 mph (205 km/h) with higher gusts. Sam is a category 3 hurricane on the Saffir-Simpson Hurricane Wind Scale. Fluctuations in intensity are possible during the next days, although Sam is forecast to remain a major hurricane through at least Thursday night. Hurricane-force winds extend outward up to 30 miles (45 km) from the center and tropical-storm-force winds extend outward up to 105 miles (165 km). The minimum central pressure estimated from NOAA Hurricane Hunter aircraft observations is 966 mb (28.53 inches). HAZARDS AFFECTING LAND ---------------------- SURF: Swells generated by Sam will reach the Lesser Antilles today and impact these islands for the next several days. Swells are expected to reach Bermuda and the Bahamas mid-to-late week, and then spread to the United States east coast late this week. These swells could 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 Hagen/Pasch

...HURRICANE HUNTER AIRCRAFT CURRENTLY INVESTIGATING SAM... As of 11:00 AM AST Mon Sep 27 the center of Sam was located near 15.7, -52.1 with movement NW at 8 mph. The minimum central pressure was 966 mb with maximum sustained winds of about 125 mph.

Issued at 1500 UTC MON SEP 27 2021 000 WTNT23 KNHC 271452 TCMAT3 HURRICANE SAM FORECAST/ADVISORY NUMBER 20 NWS NATIONAL HURRICANE CENTER MIAMI FL AL182021 1500 UTC MON SEP 27 2021 THERE ARE NO COASTAL WATCHES OR WARNINGS IN EFFECT. HURRICANE CENTER LOCATED NEAR 15.7N 52.1W AT 27/1500Z POSITION ACCURATE WITHIN 15 NM PRESENT MOVEMENT TOWARD THE NORTHWEST OR 310 DEGREES AT 7 KT ESTIMATED MINIMUM CENTRAL PRESSURE 966 MB MAX SUSTAINED WINDS 110 KT WITH GUSTS TO 135 KT. 64 KT....... 25NE 20SE 20SW 20NW. 50 KT....... 40NE 30SE 30SW 35NW. 34 KT....... 90NE 90SE 60SW 80NW. 12 FT SEAS..120NE 90SE 120SW 120NW. WINDS AND SEAS VARY GREATLY IN EACH QUADRANT. RADII IN NAUTICAL MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT. REPEAT...CENTER LOCATED NEAR 15.7N 52.1W AT 27/1500Z AT 27/1200Z CENTER WAS LOCATED NEAR 15.4N 51.7W FORECAST VALID 28/0000Z 16.4N 52.8W MAX WIND 110 KT...GUSTS 135 KT. 64 KT... 25NE 20SE 20SW 20NW. 50 KT... 40NE 30SE 30SW 35NW. 34 KT... 90NE 90SE 60SW 80NW. FORECAST VALID 28/1200Z 17.3N 53.9W MAX WIND 110 KT...GUSTS 135 KT. 64 KT... 30NE 25SE 20SW 25NW. 50 KT... 50NE 40SE 30SW 40NW. 34 KT... 90NE 90SE 60SW 80NW. FORECAST VALID 29/0000Z 18.1N 55.1W MAX WIND 110 KT...GUSTS 135 KT. 64 KT... 30NE 25SE 20SW 25NW. 50 KT... 50NE 40SE 30SW 40NW. 34 KT... 90NE 90SE 60SW 80NW. FORECAST VALID 29/1200Z 19.1N 56.5W MAX WIND 110 KT...GUSTS 135 KT. 64 KT... 40NE 30SE 25SW 30NW. 50 KT... 60NE 50SE 40SW 50NW. 34 KT...100NE 90SE 70SW 80NW. FORECAST VALID 30/0000Z 20.2N 58.1W MAX WIND 110 KT...GUSTS 135 KT. 50 KT... 60NE 50SE 40SW 50NW. 34 KT...110NE 100SE 70SW 80NW. FORECAST VALID 30/1200Z 21.7N 59.8W MAX WIND 110 KT...GUSTS 135 KT. 50 KT... 60NE 60SE 50SW 50NW. 34 KT...110NE 110SE 80SW 90NW. 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 01/1200Z 25.9N 62.2W MAX WIND 110 KT...GUSTS 135 KT. OUTLOOK VALID 02/1200Z 32.0N 61.3W MAX WIND 100 KT...GUSTS 120 KT. REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 15.7N 52.1W NEXT ADVISORY AT 27/2100Z $$ FORECASTER HAGEN/PASCH

000
ABNT20 KNHC 271152 CCA
TWOAT

Tropical Weather Outlook...Corrected
NWS National Hurricane Center Miami FL
800 AM EDT Mon Sep 27 2021

Corrected formation chances to medium in last two paragraphs

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

The National Hurricane Center is issuing advisories on Hurricane
Sam, located several hundred miles east of the Lesser Antilles.

An elongated area of low pressure associated with the remnants of
Peter is located a few hundred miles east-southeast of Bermuda.
Showers and thunderstorms associated with this system have changed
little in organization since yesterday. However, environmental
conditions are marginally conducive for some further development,
and Peter could briefly become a tropical depression again during
the next day or two while it moves northeastward near 10 mph.
By midweek, environmental conditions are expected to become
unfavorable for further development.
* Formation chance through 48 hours...medium...50 percent.
* Formation chance through 5 days...medium...50 percent.

Disorganized showers and thunderstorms are associated with a broad
area of low pressure located several hundred miles southwest of the
Cabo Verde Islands. Environmental conditions are forecast to be
conducive for further development of this disturbance, and a
tropical depression is likely to form in a few days while it moves
westward to west-northwestward at 5 to 10 mph over the central
tropical Atlantic.
* Formation chance through 48 hours...medium...40 percent.
* Formation chance through 5 days...high...80 percent.

A tropical wave is moving offshore the west coast of Africa and
into the far eastern tropical Atlantic. Upper-level winds are
forecast to be conducive for gradual development, and a tropical
depression is likely to form in a few days while the system moves
westward to west-northwestward at 10 to 15 mph over the far eastern
tropical Atlantic.
* Formation chance through 48 hours...medium...40 percent.
* Formation chance through 5 days...high...80 percent.

$$
Forecaster Hagen/Pasch

000
ABNT20 KNHC 201134
TWOAT

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
800 AM EDT Mon Sep 20 2021

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

The National Hurricane Center is issuing advisories on Tropical
Storm Peter, located east-northeast of the northernmost Leeward
Islands, and on Tropical Storm Rose, located over the eastern
tropical Atlantic Ocean.

A tropical wave located over the far eastern tropical Atlantic
several hundred miles south-southeast of the Cabo Verde Islands
is producing an area of showers and thunderstorms that are showing
some signs of organization. Upper-level winds are expected to
become more conducive for further development by midweek, and a
tropical depression is likely to form by Friday while the system
moves westward at 10 to 15 mph across the eastern and central
tropical Atlantic Ocean.
* Formation chance through 48 hours...low...20 percent.
* Formation chance through 5 days...high...70 percent.

A storm-force, non-tropical low pressure system, the remnants
of Odette, is located a couple of hundred miles southeast of
Newfoundland. This low could acquire some subtropical
characteristics by the middle of this week as it moves slowly
southeastward over warmer waters across the north-central Atlantic
Ocean before moving northward out of the area over the weekend.
Additional information on this system, including storm warnings, can
be found in High Seas Forecasts issued by the National Weather
Service.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 5 days...low...30 percent.

&&

High Seas Forecasts issued by the National Weather Service can be
found under AWIPS header NFDHSFAT1, WMO header FZNT01 KWBC, and
online at ocean.weather.gov/shtml/NFDHSFAT1.php

$$
Forecaster Blake

Issued at 500 AM AST Mon Sep 20 2021 000 WTNT42 KNHC 200859 TCDAT2 Tropical Storm Rose Discussion Number 5 NWS National Hurricane Center Miami FL AL172021 500 AM AST Mon Sep 20 2021 Rose remains a sheared tropical storm with the low-level center located near the eastern edge of the convective cloud mass based on an earlier 0359Z AMSR2 microwave overpass. These same data also revealed that a well-defined mid-level circulation center was located about 80-90 nmi west of the low-level center, an indication of the magnitude and effect of the mid-level shear impinging on the cyclone. The intensity of 35 kt is being maintained for this advisory based on subjective Dvorak satellite intensity estimates of 35 from both TAFB and SAB. Objective estimates from UW-CIMSS are higher at 45-55 kt, which are considered to be unrepresentative due to the severe westward tilt of Rose's vortex column. The initial motion estimate is northwestward or 315/13 kt. Rose is expected to move generally northwestward around the southwestern and western periphery of a strong subtropical ridge during the next few days. By day 4 and beyond, a mid- to upper-level trough over the north-central Atlantic is forecast to dig southeastward, causing the cyclone to turn northward. The latest NHC model guidance remains in excellent agreement on this track scenario through 72 hours, but then diverge significantly thereafter owing to whether Rose weakens to shallow system or remains a little stringer and deeper. The weaker solutions go more toward the northwest and the stronger solutions take Rose northeastward. The NHC forecast track on days 4 and 5 is a blend of these two extremes. Rose only has about 24 hours over warm waters and in a weak vertical wind shear regime that will allow for some addition strengthening to occur. On days 2-5, however, increasing westerly shear is expected to induce some gradual weakening. Rose is forecast to weaken to a tropical depression by 96 hours, although some of the models suggest that weakening could occur faster than indicated below, and that Rose could degenerate into a remnant low by the end of the forecast period. FORECAST POSITIONS AND MAX WINDS INIT 20/0900Z 15.9N 32.6W 35 KT 40 MPH 12H 20/1800Z 17.5N 33.8W 40 KT 45 MPH 24H 21/0600Z 19.8N 35.5W 40 KT 45 MPH 36H 21/1800Z 21.7N 36.7W 35 KT 40 MPH 48H 22/0600Z 23.0N 37.7W 35 KT 40 MPH 60H 22/1800Z 24.2N 38.7W 35 KT 40 MPH 72H 23/0600Z 25.2N 39.8W 30 KT 35 MPH 96H 24/0600Z 27.3N 41.3W 25 KT 30 MPH 120H 25/0600Z 29.2N 40.6W 25 KT 30 MPH $$ Forecaster Stewart

Issued at 500 AM AST Mon Sep 20 2021 000 WTNT41 KNHC 200848 CCA TCDAT1 Tropical Storm Peter Discussion Number 7...Corrected NWS National Hurricane Center Miami FL AL162021 500 AM AST Mon Sep 20 2021 Corrected name of storm in first and second paragraphs Peter is a strongly sheared tropical storm. Reconnaissance wind data, conventional satellite imagery, and passive microwave satellite data indicate that Peter's center is located just to the west of the deep convection. Data from the aircraft support holding the intensity at 45 kt for now based on 925-mb flight-level and SFMR winds of 53 kt and 41 kt, respectively, on their last leg when the aircraft came in from the northeast. The central pressure had also increased only slightly to 1006 mb. Peter has continued to move west-northwestward, or 295/12 kt. There are no significant changes to the previous track forecast or reasoning. Peter is expected to move around the southwestern and western periphery of a subtropical ridge for the next couple of days, followed by a slow northward motion on days 3-5 as the cyclone moves through a weakness in the ridge induced by the southward-moving former Tropical Storm Odette. The new NHC track forecast is very similar to the previous advisory track, and lies just to the east of the tightly packed consensus track models. Some fluctuations in intensity will be possible during the next 24-36 hours owing to 5-10 kt fluctuations in the magnitude and also the direction of the deep-layer vertical wind shear. However, by 48 hours and beyond, a slow weakening trend is expected due to the shear increasing from the southwest and west-southwest of near 30 kt. The new official intensity forecast is essentially just an update of the previous advisory, and closely follows the IVCN and HCCA intensity consensus models. Based on the latest track, intensity, and wind radii forecasts, no tropical storm watches or warnings are required for the northern Leeward Islands, Virgin Islands, or Puerto Rico at this time. However, locally heavy rain is possible on Monday and Tuesday when Peter is expected to pass to the north of these locations. Key Messages: Rainfall around the southern periphery of Tropical Storm Peter may lead to areas of urban and small stream flooding through Tuesday across Puerto Rico, the Virgin Islands, and the Northern Leeward Islands. FORECAST POSITIONS AND MAX WINDS INIT 20/0900Z 19.1N 59.5W 45 KT 50 MPH 12H 20/1800Z 19.7N 61.4W 40 KT 45 MPH 24H 21/0600Z 20.4N 63.6W 40 KT 45 MPH 36H 21/1800Z 21.4N 65.5W 35 KT 40 MPH 48H 22/0600Z 22.4N 67.2W 35 KT 40 MPH 60H 22/1800Z 23.2N 68.0W 30 KT 35 MPH 72H 23/0600Z 24.2N 68.4W 30 KT 35 MPH 96H 24/0600Z 26.2N 67.8W 25 KT 30 MPH 120H 25/0600Z 28.5N 66.8W 30 KT 35 MPH $$ Forecaster Stewart

5-Day Uncertainty Track last updated Mon, 20 Sep 2021 08:43:45 GMT


Wind Speed Probabilities last updated Mon, 20 Sep 2021 09:29:32 GMT