751 

ABNT20 KNHC 271906 CCB

TWOAT 



Tropical Weather Outlook...Corrected

NWS National Hurricane Center Miami FL

200 PM EDT Mon Sep 27 2021



Corrected geographic reference for the remnants of Peter



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.



The area of low pressure associated with the remnants of Peter is 

located a few hundred miles east of Bermuda.  The low has become 

better defined today, and the shower and thunderstorm activity has 

become a little better organized.  Any further increase in 

organization could result in the formation of a short-lived tropical 

depression, while it moves northeastward at about 10 mph.  By 

Wednesday, environmental conditions are expected to become 

unfavorable for further development.

* Formation chance through 48 hours...medium...60 percent.

* Formation chance through 5 days...medium...60 percent.



A broad area of low pressure located several hundred miles southwest 

of the Cabo Verde Islands is producing disorganized showers and 

thunderstorms.  Environmental conditions are conducive for further 

development of this disturbance, and a tropical depression is likely 

to form in a few of days while it moves westward to 

west-northwestward at 5 to 10 mph over the central tropical 

Atlantic.

* Formation chance through 48 hours...medium...50 percent.

* Formation chance through 5 days...high...80 percent.



A tropical wave located just offshore the west coast of Africa is 

producing a large area of disorganized showers and thunderstorms.  

Upper-level winds are 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...50 percent.

* Formation chance through 5 days...high...80 percent.



$$

Forecaster Hagen/Pasch



]]>

Hurricane for

• Summary for Hurricane Sam (AT3/AL182021)
  ...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.

Hurricane Sam

• Hurricane Sam Public Advisory Number 20
  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 Sam Forecast Advisory Number 20
  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 ]]>
• Hurricane Sam Forecast Discussion Number 20
  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 ]]>
• Hurricane Sam Wind Speed Probabilities Number 20
  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 ]]>
• Hurricane Sam Graphics
  
  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 ]]>