154
AXNT20 KNHC 230440
TWDAT
TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
0615 UTC WED SEP 23 2026
TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA, CENTRAL AMERICA
GULF OF AMERICA, CARIBBEAN SEA, NORTHERN SECTIONS OF SOUTH
AMERICA, AND ATLANTIC OCEAN TO THE AFRICAN COAST FROM THE
EQUATOR TO 31N. THE FOLLOWING INFORMATION IS BASED ON SATELLITE
IMAGERY, WEATHER OBSERVATIONS, RADAR AND METEOROLOGICAL ANALYSIS.
BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
0330 UTC.
..SPECIAL FEATURES
HEAVY RAINFALL IN CENTRAL AMERICA, JAMAICA, AND CUBA: A MIDDLE TO
UPPER-LEVEL TROUGH CURRENTLY EXTENDS FROM THE EASTERN GULF OF
AMERICA ACROSS THE YUCATAN PENINSULA AND NW CARIBBEAN, WHILE
RELATIVELY WARM SEA SURFACE TEMPERATURES AND ABUNDANT LOW LEVEL
MOISTURE ARE PRESENT. AN ELONGATED LOW LEVEL TROUGH WILL DEVELOP
ACROSS THIS AREA DURING THE NEXT SEVERAL DAYS, AND AID IN
FUNNELING ENHANCED TROPICAL MOISTURE ACROSS CENTRAL AMERICA AND
THE WESTERN CARIBBEAN, SUPPORTING PERIODS OF HEAVY RAINFALL
TONIGHT THROUGH SAT THE 26TH. THERE IS STILL SOME UNCERTAINTY
REGARDING THE EXACT LOCATION OF HEAVIEST RAINFALL, BUT FOR NOW
HEAVY RAINFALL LOOKS LIKELY ACROSS EXTREME SOUTHEASTERN MEXICO
NEAR CHIAPAS, SOUTHERN AND CENTRAL GUATEMALA, WESTERN HONDURAS, EL
SALVADOR, SOUTHERN AND EASTERN BELIZE, AS WELL AS ACROSS PORTIONS
OF COSTA RICA AND PANAMA. CURRENTLY, VERY HEAVY RAINFALL IS
ONGOING FROM THE NW COASTAL WATERS OF JAMAICA, WESTWARD ACROSS THE
CAYMAN ISLANDS TO 83W AND THEN NORTHWARD ACROSS EAST-CENTRAL CUBA
TO ANDROS ISLAND IN THE BAHAMAS. SCATTERED POCKETS OF MODERATE
CONVECTION ARE ELSEWHERE ACROSS THE GULF OF HONDURAS, AND THE
REMAINDER OF THE BAHAMAS. HEAVY RAINFALL IN THESE REGIONS WILL
CREATE THE POSSIBILITY OF LIFE- THREATENING FLASH FLOODING AND
LANDSLIDES. PLEASE REFER TO LOCAL WEATHER SERVICES AS WELL AS THE
INTERNATIONAL DESK AT THE WEATHER PREDICTION CENTER FOR MORE
INFORMATION.
..TROPICAL WAVES
AN ATLANTIC TROPICAL WAVE IS ANALYZED ALONG 40W, S OF 15N, MOVING
WESTWARD AT 15 KT. SCATTERED MODERATE CONVECTION IS ABOUT THE
MONSOON TROUGH IN THIS AREA FROM 10N TO 11.5N BETWEEN 38W AND 45W.
AN ATLANTIC TROPICAL WAVE HAS ITS AXIS ALONG 56W SOUTH OF 16N,
MOVING WESTWARD AT 10 TO 15 KT. WIDELY SCATTERED SHOWERS AND
ISOLATED THUNDERSTORMS ARE NOTED FROM 08.5N TO 11.5N BETWEEN 54W
AND 60W.
..MONSOON TROUGH/ITCZ
THE MONSOON TROUGH AXIS EXITS AFRICA ALONG THE GUINEA COAST NEAR
10N14.5W AND EXTENDS SOUTHWESTWARD TO 1009 MB LOW PRESSURE NEAR
09N16W TO 10.5N23W TO 09.5N43W, WHERE IT TRANSITIONS TO THE ITCZ
AND CONTINUES TO 08N50W AND TO 09N56W. SCATTERED TO LOCALLY
NUMEROUS MODERATE TO STRONG CONVECTION IS NOTED FROM 05.5N TO
11.5N E OF 25W TO THE COAST OF AFRICA.
..GULF OF AMERICA
A VERY WEAK PRESSURE GRADIENT REMAINS ACROSS THE GULF BASIN AS
WEAKENING HIGH PRESSURE ACROSS THE SE U.S. EXTENDS A RIDGE ACROSS
THE NORTHERN GULF. A BROAD AND PERSISTENT MIDDLE TO UPPER-LEVEL
TROUGH OVER THE EASTERN GULF IS SUPPORTING VERY ACTIVE
THUNDERSTORMS OVER PORTIONS OF THE NW CARIBBEAN AND ACROSS EASTERN
CUBA INTO THE BAHAMAS, WHILE CONVECTION ACROSS THE GULF HAS
DIMINISHED IN RECENT HOURS, WITH WIDELY SCATTERED MODERATE
CONVECTION ACROSS THE STRAITS OF FLORIDA AND INTO THE SW FLORIDA
WATERS ACROSS THE FORT MEYERS AREA. A WEAK SURFACE TROUGH LINGERS
FROM CENTRAL FLORIDA INTO THE THE SW GULF TO THE WESTERN STRAITS
OF FLORIDA. THE CURRENT SURFACE PATTERN IS GENERALLY PRODUCING
LIGHT TO GENTLE EASTERLY WINDS AND SLIGHT SEAS ACROSS THE GULF.
MODERATE E-NE WINDS AND SEAS TO 3 FT ARE OCCURRING WELL OFFSHORE
OF SOUTHERN TEXAS BETWEEN 93W AND 95W.
FOR THE FORECAST, THE CURRENT WEAK PRESSURE PATTERN ACROSS THE
GULF WILL CONTINUE TO GENERATE GENTLE TO MODERATE WINDS ACROSS
THE GULF THROUGH THU. THE PERSISTENT MIDDLE TO UPPER-LEVEL TROUGH
WILL SUPPORT SCATTERED SHOWERS AND THUNDERSTORMS OVER THE SE GULF
AND THE STRAITS OF FLORIDA FOR AT LEAST THE NEXT COUPLE OF DAYS.
A COLD FRONT IS FORECAST TO MOVE INTO THE NE GULF THU NIGHT AND
FRI. THE FRONT WILL SHIFT SOUTHWARD ACCOMPANIED BY INCREASING
WINDS AND SEAS, BEFORE STALLING OVER THE SE GULF THIS WEEKEND.
..CARIBBEAN SEA
PLEASE REFER TO THE SPECIAL FEATURES SECTION ABOVE FOR INFORMATION
ON IMPACTFUL WEATHER ACROSS THE NORTHWESTERN CARIBBEAN.
OUTSIDE OF THE ACTIVE CONVECTION ACROSS THE NW CARIBBEAN, FAIR
WEATHER DOMINATES MOST OF THE BASIN. SCATTERED SHOWERS ACCOMPANY A
LOW LEVEL TROUGH MOVING ACROSS THE LEEWARD ISLANDS, WHILE EVENING
CONVECTION IS DIMINISHING ACROSS SW HISPANIOLA. AT THE SURFACE, A
WEAK PRESSURE PATTERN IS ACROSS THE BASIN, AS 1022 MB ATLANTIC
HIGH PRESSURE IS LOCATED E OF BERMUDA ALONG 57W AND EXTENDS A
RIDGE INTO THE SE BAHAMAS. MODERATE TRADES PREVAIL ACROSS MOST OF
THE BASIN E OF 76W, WHERE SEAS ARE 3 TO 5 FT, WHILE FRESH TO
STRONG WINDS ARE S OF 14N TO THE COASTS OF NW VENEZUELA AND
EXTREME NE COLOMBIA, WHERE SEAS ARE 5 TO 7 FT. OUTSIDE OF
CONVECTION, LIGHT TO GENTLE WINDS AND SLIGHT SEAS PREVAIL ACROSS
THE REMAINING WATERS OF THE WESTERN CARIBBEAN.
FOR THE FORECAST, A WEAK PRESSURE GRADIENT WILL CONTINUE ACROSS
THE BASIN TO PRODUCE MODERATE TO FRESH TRADES OVER THE S CENTRAL
CARIBBEAN, AND GENTLE TO MODERATE WINDS ELSEWHERE. A DEEP LAYERED
UPPER TROUGH OVER NW PORTIONS WILL SUPPORT SCATTERED TO NUMEROUS
SHOWERS AND THUNDERSTORMS OVER THE W CARIBBEAN FOR AT LEAST THE
NEXT COUPLE OF DAYS.
..ATLANTIC OCEAN
OF NOTE: WHAT WAS PREVIOUSLY TROPICAL DEPRESSION FAY IS NOW A
POST-TROPICAL REMNANT LOW PRESSURE OF 1013 MB CENTERED NEAR 30.5N
36W, OR ABOUT 630 NM SOUTHWEST OF THE AZORES. WINDS OF 20-30 KT
CONTINUE WITHIN 180 NM ACROSS THE N SEMICIRCLE, WHERE BUOY
OBSERVATIONS SUGGEST SEAS ARE 8 TO 13 FT. SCATTERED MODERATE
CONVECTION HAS INCREASED IN RECENT HOURS, AND WITHIN 90 NM ACROSS
THE E SEMICIRCLE OF THE LOW.
SCATTERED SHOWERS AND THUNDERSTORMS REMAIN ACTIVE ACROSS THE
NW CARIBBEAN, ACROSS EASTERN CUBA AND OVER MUCH OF THE BAHAMAS AND
ADJACENT ATLANTIC WATERS S OF 27.5N AND W OF 75W. THIS ACTIVITY
IS OCCURRING DUE TO THE COMBINATION OF AMPLE MOISTURE ACROSS THE
AREA AND UNSTABLE CONDITIONS CREATED BY THE PERSISTENT AND DEEP
LAYERED UPPER TROUGH ACROSS THE EASTERN GULF OF AMERICA AND NW
CARIBBEAN. ANOTHER UPPER-LEVEL LOW IS DRIFTING WESTWARD NEAR
26N51W. THIS FEATURE IS INTERACTING WITH SEVERAL SURFACE TROUGHS
IN THE CENTRAL ATLANTIC RESULTING IN AN AREA OF SCATTERED MODERATE
CONVECTION FROM 22.5N TO 28N BETWEEN 41W AND 53W. ANOTHER SURFACE
TROUGH IS MOVING WESTWARD ACROSS THE LESSER ANTILLES, AND PRODUCING
SCATTERED SHOWERS AND A FEW THUNDERSTORMS ACROSS THE LEEWARD
ISLANDS AND ADJACENT ATLANTIC WATERS W OF 59W. OUTSIDE OF THIS
CONVECTION, A RATHER WEAK PRESSURE GRADIENT CONTINUES ACROSS MUCH
OF THE ATLANTIC, WITH 1022 MB HIGH PRESSURE ACROSS THE ATLANTIC E
OF BERMUDA ALONG 57W PRODUCING A MODEST RIDGE INTO THE SE BAHAMAS,
WHILE A SURFACE TROUGH LINGERS FROM CENTRAL FLORIDA TO NEAR
31N76W. THIS PATTERN IS SUSTAINING MOSTLY GENTLE TO MODERATE
TRADES S OF 23N AND VARIABLE LIGHT TO GENTLE WINDS ELSEWHERE W OF
50W, EXCEPT FOR MODERATE SE TO S WINDS OVER THE AREA N OF 25N
BETWEEN 58W AND 70W. SEAS ARE 4 FT OR LESS ACROSS THIS AREA EXCEPT
5 TO 8 FT N OF 26N BETWEEN 49W AND 52W.
ELSEWHERE, THE AZORES HIGH IS CENTERED ACROSS THE NE ATLANTIC
ALONG 20W AND EXTENDS A RIDGE SOUTHWESTWARD AND DRAPES ACROSS THE
REMNANT LOW OF FAY NEAR 30.5N36W. THE RESULTANT PRESSURE GRADIENT
IS YIELDING MODERATE N TO NE WINDS FROM THE CANARY ISLANDS TO THE
CABO VERDES, WITH STRONG WINDS ALONG THE COAST OF AFRICA. SEAS
THERE ARE 3 TO 6 FT. MODERATE NE TRADES PREVAIL S OF 21N BETWEEN
THE CABO VERDES AND 50W, WHERE SEAS ARE4 TO 6 FT. N OF THIS AREA
WINDS ARE LIGHT TO GENTLE. HOWEVER, LONG PERIOD N TO NE SWELL HAS
MOVED INTO THE WATERS N OF 25N AND E OF 52W, WHERE SEAS ARE 6 TO 8
FT.
FOR THE FORECAST WEST OF 55W, A CONTINUED WEAK PRESSURE GRADIENT
WILL SUPPORT GENTLE TO MODERATE TRADES ACROSS FORECAST WATERS
THROUGH WED NIGHT. AN UPPER-LEVEL TROUGH WILL SUPPORT SCATTERED
SHOWERS AND THUNDERSTORMS WEST OF 65W FOR THE NEXT COUPLE OF DAYS.
A COLD FRONT WILL MOVE OFF THE SE UNITED STATES COAST LATE WED
NIGHT. THE FRONT WILL SHIFT EASTWARD, REACHING FROM NEAR BERMUDA
TO THE STRAITS OF FLORIDA SAT NIGHT BEFORE STARTING TO WEAKEN.
FRESH TO STRONG WINDS AND INCREASING SEAS IN LARGE NE SWELL WILL
FOLLOW THE FRONT ON THU AND FRI.
STRIPLING
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