365
FXCA20 KWBC 231833
PMDCA
TROPICAL DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
233 PM EDT FRI OCT 23 2026
FORECAST BULLETIN 23 OCTOBER 2026 AT 1830 UTC:
(CORRECTION)
AN UPPER-LEVEL TROUGH EXTENDING OVER THE EASTERN U.S. TO THE
YUCATAN PENINSULA WILL PROPAGATE SLOWLY SOUTHEASTWARD OVER THE
NEXT THREE DAYS WHILE SUPPORTING STRONG UPPER-LEVEL VENTILATION
OVER EASTERN CUBA, EASTERN JAMAICA, HISPANIOLA, AND THE
SOUTHEASTERN BAHAMAS. AT MID-LEVELS, ABUNDANT REGIONS OF VORTICITY
WILL SUPPORT STRONG UPWARD MOTION, WHILE A SERIES OF LOW-LEVEL
TROUGHS AND CUT-OFF LOWS WILL DEVELOP TO FAVOR LOW-LEVEL MOISTURE
CONVERGENCE TO TRIGGER HEAVY THUNDERSTORMS.
MID-LEVEL WINDS WILL ADVECT MOISTURE FROM THE VICINITY OF
HURRICANE VANCE, LOCATED OFF THE SOUTH COAST OF MEXICO, INTO
NORTHERN CENTRAL AMERICA TODAY. THE LOW-LEVEL WIND PATTERN IS
FORECAST TO SHIFT FROM NORTHEAST TO NORTH OVER THE NEXT FEW HOURS
AS A SHORTWAVE ALOFT CONTINUES TO PROPAGATE SOUTHEASTWARD. THIS
FORCED WIND SHIFT WILL HELP DEVELOP A LOW-LEVEL TROUGH THAT WILL
INTERACT WITH LOCAL OROGRAPHY OVER NORTHERN HONDURAS TO SUPPORT
LOW-LEVEL MOISTURE CONVERGENCE AND STRATIFORM SHOWERS. THE
LOW-LEVEL FEATURE IS EXPECTED TO REMAIN THROUGH THE NEXT FEW DAYS,
BUT A DRIER AIR MASS WILL MOVE IN OVER THE WEEKEND, LIMITING DAILY
RAINFALL TOTALS.
OVER THE NEXT THREE DAYS, FEEDER BANDS ASSOCIATED WITH HURRICANE
VANCE WILL CONTINUE TO BRING RAINFALL ALONG THE PACIFIC COAST OF
MEXICO, EXTENDING FROM GUERRERO TO JALISCO. THE HIGHEST DAILY
ACCUMULATION TOTALS ARE EXPECTED ON SUNDAY AS THE SYSTEM MOVES
CLOSER TO THE COAST, WITH MAXIMUM DAILY ACCUMULATIONS REACHING
20-35 MM.
A SERIES OF LOW-LEVEL TROUGHS EXTENDING OVER SOUTHERN CENTRAL
AMERICA AND ALONG THE PACIFIC COLOMBIAN COAST WILL SUPPORT STRONG
LOW-LEVEL MOISTURE CONVERGENCE TO ENHANCE PRECIPITABLE WATER
ANOMALIES BETWEEN 1 AND 2 STANDARD DEVIATIONS OVER THE NEXT THREE
DAYS. ELEVATED VERTICAL VORTICITY ADVECTION OVER NORTHERN COLOMBIA
WILL FAVOR HEAVY RAINFALL ACCUMULATIONS OVER THE NEXT THREE DAYS.
A STRONG MID- TO UPPER-LEVEL ANTICYCLONE EXTENDING OVER BRAZIL
WILL SUPPRESS CONVECTION ACROSS EASTERN AREAS, FOCUSING THE
HIGHEST RAINFALL TOTALS OVER WESTERN ORINOQUIA AND THE WESTERN
AMAZON BASIN TODAY. AS THIS SYSTEM DRIFTS WESTWARD OVER THE NEXT
THREE DAYS, MAIN AREAS OF RAINFALL WILL REMAIN CONSTRAINED TO ITS
WESTERN FLANK.
SANCHEZ-PEREZ...(WPC)
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page