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BULLETIN
POST-TROPICAL CYCLONE JOYCE ADVISORY NUMBER 9
NWS NATIONAL HURRICANE CENTER MIAMI FL AL102012
1100 AM AST FRI AUG 24 2012

…JOYCE DEGENERATES INTO A REMNANT LOW…

SUMMARY OF 1100 AM AST…1500 UTC…INFORMATION
———————————————–
LOCATION…17.8N 46.2W
ABOUT 1030 MI…1655 KM E OF THE LEEWARD ISLANDS
MAXIMUM SUSTAINED WINDS…35 MPH…55 KM/H
PRESENT MOVEMENT…WNW OR 300 DEGREES AT 16 MPH…26 KM/H
MINIMUM CENTRAL PRESSURE…1009 MB…29.80 INCHES

WATCHES AND WARNINGS
——————–
THERE ARE NO COASTAL WATCHES OR WARNINGS IN EFFECT.

DISCUSSION AND 48-HOUR OUTLOOK
——————————
SATELLITE IMAGES INDICATE THAT JOYCE HAS DEGENERATED INTO A BROAD
AREA OF LOW PRESSURE. AT 1100 AM AST…1500 UTC…THE CENTER OF THE
REMNANT LOW WAS LOCATED NEAR LATITUDE 17.8 NORTH…LONGITUDE 46.2
WEST. THE LOW IS MOVING TOWARD THE WEST-NORTHWEST NEAR 15 MPH…24
KM/H. SOME INCREASE IN FORWARD SPEED IS EXPECTED DURING THE NEXT
COUPLE OF DAYS…WITH A TURN TOWARD THE NORTHWEST FORECAST ON
SUNDAY.

MAXIMUM SUSTAINED WINDS ARE NEAR 35 MPH…55 KM/H…WITH HIGHER
GUSTS. LITTLE CHANGE IN STRENGTH IS FORECAST DURING THE NEXT 48
HOURS…BUT THE REMNANT LOW COULD DEGENERATE INTO A TROUGH AT ANY
TIME.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 1009 MB…29.80 INCHES.

HAZARDS AFFECTING LAND
———————-
NONE

NEXT ADVISORY
————-
THIS IS THE LAST PUBLIC ADVISORY ISSUED BY THE NATIONAL HURRICANE
CENTER ON THIS SYSTEM UNLESS REGENERATION OCCURS. ADDITIONAL
INFORMATION ON THIS SYSTEM CAN BE FOUND IN HIGH SEAS FORECASTS
ISSUED BY THE NATIONAL WEATHER SERVICE…UNDER AWIPS HEADER
NFDHSFAT1 AND WMO HEADER FZNT01 KWBC.

POST-TROPICAL CYCLONE JOYCE DISCUSSION NUMBER 9
NWS NATIONAL HURRICANE CENTER MIAMI FL AL102012
1100 AM AST FRI AUG 24 2012

VISIBLE SATELLITE IMAGERY INDICATES THAT THE CENTER OF CIRCULATION
HAS BECOME ILL DEFINED…AND THE CIRCULATION ITSELF MAY NOT EVEN BE
CLOSED ANYMORE. ALTHOUGH THE CYCLONE IS PRODUCING SOME CONVECTION
IN THE NORTHERN SEMICIRCLE…THE SHOWERS AND THUNDERSTORMS ARE NOT
WELL ORGANIZED. JOYCE NO LONGER SATISFIES THE CRITERIA FOR BEING A
TROPICAL CYCLONE…AND IT IS THEREFORE BEING DESIGNATED AS A REMNANT
LOW. THIS WILL BE THE LAST ADVISORY UNLESS REGENERATION OCCURS.

BASED ON ANALYSES FROM UW-CIMSS…JOYCE IS BEING AFFECTED BY ABOUT
20 KT OF SOUTH-SOUTHEASTERLY SHEAR…AND IT IS EMBEDDED IN A DRY
MID-LEVEL ENVIRONMENT. THESE PARAMETERS ARE NOT EXPECTED TO
CHANGE APPRECIABLY DURING THE NEXT COUPLE OF DAYS…AND THE
PROSPECTS OF REGENERATION AND STRENGTHENING APPEAR LOW AT THIS TIME.
THE NHC OFFICIAL FORECAST HOLDS THE CYCLONE AS A REMNANT LOW
THROUGH THE 5-DAY FORECAST…BUT IT IS ENTIRELY POSSIBLE THAT THE
LOW COULD DISSIPATE AT ANY TIME.

THE INITIAL MOTION ESTIMATE IS 300/13. THE LOW IS EXPECTED TO
MAINTAIN A WEST-NORTHWESTWARD HEADING WITH SOME ACCELERATION AS IT
MOVES ALONG THE SOUTHWESTERN PERIPHERY OF A LOW/MID-LEVEL
SUBTROPICAL RIDGE. THE REMNANTS SHOULD REACH THE WESTERN EXTENT OF
THE RIDGE IN 3-4 DAYS…AND ARE FORECAST TO RE-CURVE TOWARD THE
NORTHEAST BY DAY 5. THE TRACK GUIDANCE IS STILL IN RELATIVELY GOOD
AGREEMENT…AND THE NEW NHC FORECAST IS JUST AN UPDATE OF THE
PREVIOUS ONE.

ADDITIONAL INFORMATION ON THIS SYSTEM CAN BE FOUND IN HIGH SEAS
FORECASTS ISSUED BY THE NATIONAL WEATHER SERVICE…UNDER AWIPS
HEADER NFDHSFAT1 AND WMO HEADER FZNT01 KWBC.

FORECAST POSITIONS AND MAX WINDS

INIT 24/1500Z 17.8N 46.2W 30 KT 35 MPH…POST-TROP/REMNT LOW
12H 25/0000Z 18.7N 48.6W 30 KT 35 MPH…POST-TROP/REMNT LOW
24H 25/1200Z 20.3N 52.1W 25 KT 30 MPH…POST-TROP/REMNT LOW
36H 26/0000Z 22.1N 55.5W 25 KT 30 MPH…POST-TROP/REMNT LOW
48H 26/1200Z 24.5N 58.7W 25 KT 30 MPH…POST-TROP/REMNT LOW
72H 27/1200Z 29.0N 63.5W 25 KT 30 MPH…POST-TROP/REMNT LOW
96H 28/1200Z 33.5N 62.0W 25 KT 30 MPH…POST-TROP/REMNT LOW
120H 29/1200Z 37.5N 53.0W 25 KT 30 MPH…POST-TROP/REMNT LOW

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