568  
FXCA20 KWBC 161856  
PMDCA  
 
TROPICAL DISCUSSION - INTERNATIONAL DESKS  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
255 PM EDT THU APR 16 2026  
 
FORECAST BULLETIN 16 APRIL 2026 AT 1900 UTC:  
 
IN THE UPPER LEVELS...  
 
AN UPPER LEVEL TROUGH IS CURRENTLY ENTERING THE CONTINENTAL UNITED  
STATES AND WILL INFLUENCE THE PROPAGATION OF TWO DISTINCT UPPER  
LEVEL FEATURES IN THE CARIBBEAN. STARTING SATURDAY MORNING, THE  
TROUGH AXIS WILL BE LOCATED ACROSS THE UNITED STATES CENTRAL  
PLAINS AND WILL ALSO INTERACT WITH ANOTHER UPPER LEVEL TROUGH THAT  
IS EMBEDDED WITHIN THE SUBTROPICAL JET STREAM. AS THESE FEATURES  
INTERACT, THEY WILL DISPLACE A PRE-EXISTING RIDGE THAT IS  
CURRENTLY SITUATED ACROSS SOUTHERN MEXICO AND NORTH CENTRAL  
AMERICA. THIS RIDGE WILL START TO EXTEND INTO THE INTERIOR OF THE  
CARIBBEAN SEA ON SATURDAY AND IS EXPECTED TO WEAKEN BY THE END OF  
THE WEEKEND. ANOTHER UPPER LEVEL TROUGH IS CURRENTLY EXTENDING  
FROM THE GREATER ANTILLES AND INTO THE CARIBBEAN SEA AND IT WILL  
CONTINUE TO INFLUENCE THE UPPER LEVEL PATTERNS IN THE REGION FOR  
THE NEXT THREE DAYS. ON THURSDAY AND FRIDAY, THE UPPER TROUGH WILL  
BE PROMOTING SPEED DIVERGENCE ACROSS COLOMBIA AND VENEZUELA.  
STARTING ON SATURDAY, THE TROUGH WILL TIGHTEN AND WILL PROPAGATE  
EASTWARD AS IT BECOMES DISPLACED BY THE AFOREMENTIONED UPPER  
RIDGE.  
 
IN THE MID TO LOW LEVELS...  
 
ACROSS HISPANIOLA, PUERTO RICO, AND THE VIRGIN ISLANDS (VI), THE  
PRESENCE OF THE UPPER LEVEL IS SUPPORTING THE MOISTENING OF THE  
ENVIRONMENT AND PRECIPITABLE WATER VALUES WILL BE REACHING 45MM  
FOR THURSDAY AND FRIDAY. AS THE UPPER TROUGH AXIS SHIFTS EASTWARD  
ON SATURDAY, EXPECT DRIER CONDITIONS TO RETURN. MEANWHILE, A  
TROUGH IS EXPECTED TO MOVE OUT OF HISPANIOLA BY THURSDAY AFTERNOON  
AND EASTERLY AND SOUTHEASTERLY WINDS WILL DOMINATE THEREAFTER. ON  
FRIDAY AND SATURDAY, LOCALIZED SURFACE-TO-LOW LEVEL WIND  
CONFLUENCE IS EXPECTED IN HISPANIOLA, PUERTO RICO, AND THE VI.  
WITH RESPECT TO PRECIPITATION, MODERATE TOTAL PRECIPITATION MAXIMA  
WILL OCCUR IN THE AFOREMENTIONED REGIONS FOR THURSDAY AND FRIDAY  
AND DECREASING FOR SATURDAY.  
 
ALONG THE NORTHWEST REGION OF SOUTH AMERICA AND PANAMA, THE  
INCREASE IN NORTHERLY LOW LEVEL WINDS ACROSS PANAMA AND INTO THE  
GULF OF PANAMA WILL ASSIST IN THE TRANSPORT OF DRY AIR FROM THE  
CARIBBEAN SEA INTO COLOMBIA. ON THURSDAY, A MOIST PLUME WILL BE  
ARRIVING INTO THE LAGO DE MARACAIBO REGION AND NORTH-CENTRAL  
COLOMBIA, HELPING KEEP THE ENVIRONMENT MOIST THROUGH FRIDAY. THE  
UPPER LEVEL DYNAMICS WILL SUPPORT AN INCREASE IN INSTABILITY IN  
THESE REGIONS AND UPPER DIVERGENCE. THUS, ENHANCED TOTAL  
PRECIPITATION MAXIMA IS LIKELY ON THURSDAY. BY FRIDAY, MODERATE  
TOTAL PRECIPITATION MAXIMA IS LIKELY.  
 
STARTING ON SATURDAY AFTERNOON, A COLD FRONT WILL BE MOVING INTO  
NORTHWEST MEXICO. AS THE COLD FRONT APPROACHES, THERE WILL BE AN  
INCREASE IN LOW LEVEL SOUTHERLY WINDS ACROSS THE GULF AND INTO THE  
SOUTHERN PLAINS OF THE UNITED STATES. STARTING SATURDAY, LOW LEVEL  
WINDS WILL SHIFT FROM THE EAST AND WILL SUPPORT MOISTURE POOLING  
ACROSS TAMAULIPAS AND NUEVO LEON. JET DYNAMICS WILL ALSO BE  
PRESENT IN THIS REGION. THUS, MODERATE TOTAL PRECIPITATION MAXIMA  
AND A RISK FOR SEVERE WEATHER IS LIKELY ACROSS NUEVO LEON AND  
TAMAULIPAS ON SATURDAY.  
 
ELSEWHERE IN TROPICAL SOUTH AMERICA† 
A DIFFLUENT UPPER LEVEL PATTERN WILL BE PRESENT ACROSS THE WEST  
AMAZON BASIN, FAVORING UPPER DIVERGENCE FOR THE NEXT THREE DAYS.  
THERE WILL BE A SERIES OF LOW LEVEL TROUGHS AND REGIONS OF LOW  
LEVEL WIND CONFLUENCE THAT WILL ENHANCE MOISTURE CONVERGENCE AND  
VERTICAL ASCENT. STARTING SATURDAY, EXPECT A DRYING TREND ACROSS  
THE NORTHERN HALF OF THE WEST AND CENTRAL AMAZON BASIN, WHICH WILL  
LEAD TO LOWER TOTAL PRECIPITATION MAXIMA. ACROSS THE GUIANAS AND  
THE AMAZON DELTA, EXPECT ELEVATED PRECIPITABLE WATER VALUES FOR  
THE NEXT THREE DAYS. DAILY SHOWERS AND CONVECTION ARE EXPECTED IN  
THE REGION.  
 
TINOCO-MORALES...(WPC)  
 

 
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.

The Nexlab HPC Page Main Text Page