679
AXNT20 KNHC 222312
TWDAT
TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
0015 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
2300 UTC.
..SPECIAL FEATURES
HEAVY RAINFALL IN CENTRAL AMERICA, JAMAICA, AND CUBA: A MIDDLE TO
UPPER-LEVEL TROUGH CURRENTLY EXTENDS OVER THE NW CARIBBEAN WHILE
RELATIVELY WARM SEA SURFACE TEMPERATURES ARE PRESENT. IN ADDITION,
A CENTRAL AMERICAN GYRE LOOKS TO FORM OVER THE NEXT SEVERAL DAYS.
ALL OF THESE FACTORS WILL LEAD TO ENHANCED MOISTURE FUNNELING
INTO CENTRAL AMERICA AND THE CARIBBEAN, SUPPORTING HEAVY RAINFALL
TODAY THROUGH 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 CENTRAL CUBA TO WESTERN JAMAICA. SCATTERED POCKETS
OF MODERATE CONVECTION ARE ELSEWHERE NORTH OF ABOUT 14N AND WEST
OF 77W. HEAVY RAINFALL IN THESE REGIONS WILL RAISE CONCERNS FOR
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 EASTERN ATLANTIC TROPICAL WAVE HAS ITS AXIS NEAR 34W FROM 06N
TO 19N MOVING WESTWARD AT AROUND 10 KT. NO SIGNIFICANT
CONVECTION IS NOTED WITH THIS WAVE.
A CENTRAL ATLANTIC TROPICAL WAVE HAS ITS ALONG 55W SOUTH OF
22N. IT IS MOVING WESTWARD AT 10 TO 15 KT. SCATTERED SHOWERS AND
ISOLATED THUNDERSTORMS ARE WITHIN 180 NM EITHER SIDE OF THE WAVE
FROM 09N TO 13N.
..MONSOON TROUGH/ITCZ
THE MONSOON TROUGH AXIS EXTENDS FROM THE COAST OF AFRICA NEAR
12N16W SOUTHWESTWARD TO 10N21W AND GENERALLY WESTWARD TO 10N32W
AND TO 10N39W, WHERE IT TRANSITIONS TO THE ITCZ TO 09N46W AND
TO 08N54W. SCATTERED MODERATE TO STRONG CONVECTION IS WITHIN
240 NM SOUTH OF THE TROUGH BETWEEN 14W-20W, AND WITHIN 30 NM
NORTH OF THE TROUGH BETWEEN 16W-21W.
..GULF OF AMERICA
A VERY WEAK PRESSURE GRADIENT REMAINS ACROSS THE AREA. IT IS
GENERALLY PROVIDING FOR LIGHT TO GENTLE WINDS AND SLIGHT SEAS
ACROSS THE GULF. A RATHER BROAD UPPER-LEVEL TROUGH OVER THE
EASTERN GULF IS SUPPORTING SCATTERED SHOWERS AND ISOLATED
THUNDERSTORMS SOUTH OF ABOUT 26N AND EAST OF 86W, INCLUDING
THE STRAITS OF FLORIDA AND WATERS ADJACENT TO DRY TORTUGAS.
FOR THE FORECAST, THE AFOREMENTIONED WEAK PRESSURE GRADIENT WILL
GENERATE GENTLE TO MODERATE WINDS ACROSS THE GULF THROUGH THU.
AN UPPER- LEVEL TROUGH WILL SUPPORT SCATTERED SHOWERS AND
THUNDERSTORMS OVER THE SOUTHEASTERN 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 BEFORE STALLING OVER THE SE GULF THIS
WEEKEND.
..CARIBBEAN SEA
PLEASE REFER TO THE SPECIAL FEATURES SECTION ABOVE FOR INFORMATION
ON IMPACTFUL CONVECTION IN THE NORTHWESTERN CARIBBEAN.
OUTSIDE OF CONVECTION, A WEAK PRESSURE PATTERN IS ACROSS THE
BASIN. LATEST SATELLITE SCATTEROMETER DATA PASSES INDICATE
MODERATE TO FRESH TRADES EAST OF ABOUT 80W. SEAS ARE 4 TO 6 FT
WITH THESE TRADES AS A 2230Z SATELLITE ALTIMETER PASS WAS OF
ASSISTANCE IN VERIFYING THESE SEAS. LIGHT TO GENTLE TRADES AND
SLIGHT SEAS PREVAIL WEST OF 80W.
FOR THE FORECAST, A WEAK PRESSURE GRADIENT WILL GENERATE MODERATE
TO FRESH TRADES OVER THE SOUTH-CENTRAL CARIBBEAN, AND GENTLE TO
MODERATE WINDS ELSEWHERE. AN UPPER-LEVEL TROUGH WILL SUPPORT
SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS OVER THE WESTERN
CARIBBEAN FOR AT LEAST THE NEXT TWO DAYS.
..ATLANTIC OCEAN
OF NOTE: WHAT WAS PREVIOUSLY TROPICAL DEPRESSION FAY IS NOW A
POST-TROPICAL REMNANT LOW PRESSURE OF 1011 MB CENTERED NEAR 30.8N
35.3W, OR ABOUT 600 NM SOUTHWEST OF THE AZORES. ITS MAXIMUM
SUSTAINED WIND SPEED IS 30 KT WITH GUSTS TO 40 KT. SCATTERED
MODERATE CONVECTION IS OVER THE LOW PRESSURE CENTER, AND WITHIN
60 NM SE OF THE LOW PRESSURE.
SCATTERED SHOWERS AND THUNDERSTORMS REMAIN ACTIVE ACROSS THE
BAHAMAS, OFF THE COAST OF FLORIDA, AND BETWEEN THE BAHAMAS AND
BERMUDA, WEST OF ABOUT 65W. THIS ACTIVITY IS DUE TO THE
COMBINATION OF AMPLE DEEP-LAYER MOISTURE AND UPPER-LEVEL
DIVERGENCE SOUTHEAST OF A BROAD UPPER-LEVEL TROUGH THAT IS
OVER THE GULF OF AMERICA. ANOTHER UPPER-LEVEL LOW MOVING WESTWARD
IS SEEN ON WATER VAPOR IMAGERY FARTHER EAST NEAR 26N51W. THIS
FEATURE IS INTERACTING WITH SEVERAL SURFACE TROUGHS IN THE
CENTRAL ATLANTIC RESULTING IN AN AREA OF SCATTERED MODERATE
CONVECTION FROM 21N TO 28N BETWEEN 42W AND 53W. ANOTHER SURFACE
TROUGH IS JUST EAST OF THE LESSER ANTILLES. SCATTERED SHOWERS AND
ISOLATED THUNDERSTORMS ARE SEEN FROM 13N TO 16N BETWEEN 58W AND
61W. OUTSIDE OF CONVECTION, A RATHER WEAK PRESSURE GRADIENT
ACROSS MUCH OF THE ATLANTIC IS SUSTAINING MOSTLY GENTLE TO
MODERATE TRADES. SEAS OF 4 TO 6 FT ARE OCCURRING WITH THESE
TRADES.
FOR THE FORECAST WEST OF 55W, A WEAK PRESSURE GRADIENT WILL
GENERALLY SUPPORT GENTLE TO MODERATE TRADES ACROSS FORECAST
WATERS THROUGH WED NIGHT. AN UPPER-LEVEL TROUGH WILL PRODUCE
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
WILL FOLLOW THE FRONT ON THU AND FRI, BEFORE DECREASING ON SAT.
AGUIRRE
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