543  
FXCA62 TJSJ 062050 CCA  
AFDSJU  
 
AREA FORECAST DISCUSSION...CORRECTED  
NATIONAL WEATHER SERVICE SAN JUAN PR  
450 PM AST SUN JUL 6 2025  
   
KEY MESSAGES
 
 
* NORMAL TO ABOVE NORMAL TEMPERATURES WILL CONTINUE EACH DAY AND  
A LIMITED HEAT RISK WILL PERSIST FOR THE LOWER ELEVATIONS AND  
URBAN AREAS OF THE ISLANDS.  
 
* LOCAL AND DIURNAL EFFECTS WILL CAUSE SHOWERS WITH ISOLATED  
THUNDERSTORMS TO DEVELOP OVER PORTIONS OF THE CORDILLERA AND  
WESTERN PR DURING THE NEXT FEW DAYS.  
 
* HAZY SKIES WILL RETURN LATE IN THE WORKWEEK DUE TO SAHARAN DUST.  
 

 
   
SHORT TERM...TONIGHT THROUGH TUESDAY
 
 
SUNNY TO PARTLY CLOUDY AND HAZY SKIES PREVAILED ONCE AGAIN ACROSS  
PUERTO RICO AND THE U.S. VIRGIN ISLANDS TODAY. DIURNALLY INDUCED  
AFTERNOON SHOWERS AND ISOLATED THUNDERSTORMS DEVELOPED OVER THE  
CORDILLERA AND WESTERN PR. HOWEVER, RAINFALL ACCUMULATIONS WERE  
JUST UNDER HALF AN INCH OF RAIN BY 2 PM AST. MAXIMUM TEMPERATURES  
WERE FROM THE MID-80S TO THE LOW 90S ACROSS THE LOWER ELEVATIONS  
OF THE ISLANDS, AND FROM THE UPPER-70S TO MID-80S ACROSS THE  
HIGHER ELEVATIONS OF PUERTO RICO. THE WIND WAS FROM THE EAST  
BETWEEN 12 AND 16 MPH WITH SEA BREEZE VARIATIONS AND HIGHER GUSTS  
ACROSS COASTAL AREAS.  
 
FOR THE REST OF THE SHORT-TERM PERIOD A SIMILAR WEATHER PATTERN IS  
EXPECTED EACH DAY. A MID-TO UPPER-LEVEL RIDGE BUILDING FROM THE  
EAST WILL PROMOTE RELATIVE STABLE CONDITIONS ALOFT. HOWEVER, TRADE  
WIND PERTURBATIONS WILL BRING AN INCREASE IN PASSING SHOWERS AT  
TIMES EACH DAY ACROSS THE USVI AND EASTERN SECTIONS OF PR DURING  
THE NIGHTTIME. THEN, THE AVAILABLE MOISTURE CONTENT WILL COMBINE  
WITH LOCAL AND DIURNAL EFFECTS TO TRIGGER AFTERNOON SHOWERS WITH  
ISOLATED THUNDERSTORMS OVER PORTIONS OF THE CORDILLERA AND WESTERN  
PR. NORMAL TO ABOVE NORMAL TEMPERATURES WILL CONTINUE EACH DAY AND  
A LIMITED HEAT RISK WILL PERSIST FOR THE LOWER ELEVATIONS AND  
URBAN AREAS OF THE ISLANDS.  
   
LONG TERM...WEDNESDAY THROUGH SUNDAY
 
 
/FROM PREV DISC ISSUED AT 500 AM AST SUN JUL 6 2025/  
 
A TRADE WIND PERTURBATION WILL AFFECT THE REGION WEDNESDAY,  
BRINGING BRIEF PERIODS OF ENHANCED MOISTURE AND LOCALIZED SHOWERS.  
FOLLOWING THIS, A WEAK TROPICAL WAVE WILL CROSS THE AREA THURSDAY  
INTO FRIDAY, STEERED WESTWARD BY A STRONG BERMUDA-AZORES HIGH. A  
WIND SURGE WILL THEN BRING BREEZY TO WINDY CONDITIONS FRIDAY INTO  
THE WEEKEND, WITH 700 MB WINDS PEAKING NEAR 35–40 KNOTS. THIS  
PATTERN WILL SUPPORT ENHANCED LOW-LEVEL MOISTURE TRANSPORT, THOUGH  
MID- TO UPPER-LEVEL DRYNESS AND A STRONG TRADE WIND CAP INVERSION  
WILL LIMIT DEEPER MOISTURE AVAILABILITY AND CONVECTION. DRY AIR  
ABOVE 850 MB WILL PERSIST DUE TO SUBSIDENCE FROM MID-LEVEL RIDGING  
AND LATER REINFORCED BY A TROPICAL UPPER-TROPOSPHERIC TROUGH  
(TUTT) EXPECTED TO CROSS THE REGION SATURDAY. THE MOST SIGNIFICANT  
DRYING WILL OCCUR INTO EARLY SUNDAY, WITH PRECIPITABLE WATER  
(PWAT) FALLING WELL BELOW CLIMATOLOGICAL NORMS.  
 
LIMITED PHASING OF MOISTURE AND INSTABILITY WILL RESTRICT  
WIDESPREAD OR ORGANIZED CONVECTION; HOWEVER, SOME AFTERNOON  
CONVECTION REMAINS LIKELY EACH DAY FOLLOWING THE GENERAL WIND FLOW  
AND DRIVEN BY DIURNAL HEATING AND LOCAL EFFECTS. ACTIVITY MAY  
INCREASE LATE SUNDAY AS THE TUTT SHIFTS WEST AND PWAT RETURNS TO  
TYPICAL LEVELS. A MODERATE TO HIGH SAHARAN AIR LAYER (SAL) EVENT  
IS ANTICIPATED FROM THURSDAY ONWARD, COINCIDING WITH THE DRYING  
TREND AND STRENGTHENING WINDS. THIS WILL CONTRIBUTE TO HAZY SKIES,  
REDUCED VISIBILITY, AND OVERALL ATMOSPHERIC STABILITY.  
 
WINDS WILL GENERALLY FLOW FROM EAST TO EAST-SOUTHEAST, SHIFTING  
BRIEFLY TO EAST-NORTHEAST SATURDAY NIGHT INTO SUNDAY AS THE  
SURFACE HIGH REPOSITIONS OVER THE WESTERN ATLANTIC. TEMPERATURES  
WILL REMAIN NEAR SEASONAL NORMS, WITH FRIDAY LIKELY THE WARMEST  
DAY DUE TO THE STRONGEST SOUTHEASTERLY FLOW COMPONENT. EXCEPT FOR  
EXCESSIVE RAINFALL HAZARDS, ALL OTHER WEATHER HAZARDS—INCLUDING  
PERIODS OF EXCESSIVE HEAT, GUSTY WINDS, AND ISOLATED AFTERNOON  
LIGHTNING—ARE POSSIBLE THROUGH THE LONG-TERM PERIOD.  
 

 
   
AVIATION
 
 
(18Z TAFS)  
 
MAINLY VFR CONDITIONS EXPECTED ACROSS ALL TERMINALS DURING THE  
NEXT 24 HOURS. HOWEVER, SHRA/TSRA IN AND AROUND TJPS/TJBQ MAY  
CAUSE BRIEF MVFR CIGS THRU 06/22Z. ALSO, SHRA EN ROUTE FROM THE  
LEEWARD ISLANDS SHOULD MOVE OVER THE USVI TERMINALS BETWEEN  
06/20Z-07/03Z, THIS MAY CAUSE BRIEF MVFR CIGS. THE 06/12Z TJSJ  
SOUNDING INDICATED EAST WINDS UP TO 18 KT BLO FL050.  
 

 
   
MARINE
 
 
MODERATE EASTERLY WINDS WILL PREVAIL TODAY, BUT LOCAL EFFECTS WILL  
LEAD TO CHOPPY SEAS NEAR COASTAL AREAS OF NORTHERN PUERTO RICO,  
PROMPTING SMALL CRAFT OPERATORS TO EXERCISE CAUTION. MODERATE TO  
LOCALLY FRESH WINDS WILL RETURN TONIGHT AND PERSIST OVER THE NEXT FEW  
DAYS, EXPANDING THE AREA WHERE CAUTION IS ADVISED. SAHARAN DUST WILL  
KEEP SKIES HAZY TODAY, WITH ANOTHER EVENT EXPECTED LATER IN THE  
WORKWEEK. AFTERNOON THUNDERSTORMS MAY AFFECT COASTAL WATERS AND LOCAL  
PASSAGES, PARTICULARLY NEAR WESTERN PUERTO RICO, EACH DAY. IN  
ADDITION, TROPICAL WAVES APPROACHING TUESDAY AND THURSDAY WILL LIKELY  
INCREASE THE CHANCES FOR SHOWERS, THUNDERSTORMS, GUSTY WINDS, AND  
LOCALLY HIGHER SEAS.  
 

 
   
BEACH FORECAST
 
 
A MODERATE RISK OF RIP CURRENT IS EXPECTED ACROSS THE NORTHERN  
BEACHES OF PUERTO RICO ON MONDAY, AND EXTENDING INTO THE EAST AND  
SOUTHEAST BEACHES AND ACROSS ST. CROIX FROM TUESDAY ONWARD.  
 

 
   
FIRE WEATHER
 
 
A FIRE DANGER STATEMENT IS IN EFFECT THROUGH LATE THIS AFTERNOON  
ACROSS SOUTHERN PR. WINDS SPEEDS REACHED 16 MPH IN CABO ROJO AND  
THE RH DROPPED JUST UNDER 55% FOR 2 HOURS DURING THE MID-MORNING  
HOURS. HOWEVER, SHOWERS WERE DEVELOPING EARLY IN THE AFTERNOON  
ALONG PORTIONS OF THE CORDILLERA AND SOUTHWESTERN PR. THIS WILL  
CAUSE RH LEVELS TO RECOVER AND THE FIRE DANGER THREAT TO DECREASE  
IN GENERAL.  
 

 
   
SJU WATCHES/WARNINGS/ADVISORIES
 
 
PR...NONE.  
VI...NONE.  
AM...NONE.  

 
 

 
 
DSR/GRS  
 
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