958  
FXCA62 TJSJ 071824  
AFDSJU  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE SAN JUAN PR  
224 PM AST MON JUL 7 2025  
   
KEY MESSAGES  
 
* BREEZY CONDITIONS EXPECTED ON TUESDAY AND WEDNESDAY. CHOPPY SEAS  
AND A MODERATE RISK OF RIP CURRENTS WILL PERSIST OVER THE NEXT  
FEW DAYS. THESE MAY CREATE HAZARDOUS CONDITIONS.  
 
* DIURNALLY INDUCED AFTERNOON SHOWERS AND ISOLATED THUNDERSTORMS  
ARE EXPECTED OVER PORTIONS OF THE CORDILLERA CENTRAL AND WESTERN  
PR EACH DAY. PASSING SHOWERS WILL CONTINUE ACROSS THE USVI AND  
EASTERN SECTIONS OF PR DURING THE NIGHT/EARLY MORNING HOURS.  
 
* 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.  
 
* MODERATE TO HIGH CONCENTRATIONS OF SAHARAN DUST ARE EXPECTED TO  
RETURN DURING THE SECOND PART OF THE WORKWEEK, RESULTING IN HAZY  
SKIES, REDUCED VISIBILITY, AND POOR AIR QUALITY.  
 
 
   
SHORT TERM...TONIGHT THROUGH WEDNESDAY  
 
VARIABLY CLOUDY SKIES PREVAILED ACROSS PUERTO RICO AND THE U.S.  
VIRGIN ISLANDS TODAY. TRADE WIND SHOWERS MOVED OVER PORTIONS OF  
THE USVI AND THE EASTERN HALF OF PR DURING THE MORNING HOURS.  
DIURNALLY INDUCED AFTERNOON SHOWERS AND ISOLATED THUNDERSTORMS  
DEVELOPED OVER CENTRAL AND WESTERN PR. AS OF 2 PM, RAINFALL  
ACCUMULATIONS WERE UP TO 1.50 INCHES OVER PORTIONS OF LAS MARIAS,  
MAYAGUEZ, AND CABO ROJO. MAXIMUM TEMPERATURES WERE FROM THE  
UPPER-80S TO THE LOW 90S ACROSS THE LOWER ELEVATIONS OF THE  
ISLANDS, AND FROM THE MID-70S TO MID-80S ACROSS THE HIGHER  
ELEVATIONS OF PUERTO RICO. THE WIND WAS FROM THE EAST BETWEEN 15  
AND 20 MPH WITH SEA BREEZE VARIATIONS AND HIGHER GUSTS UP TO 32  
MPH OBSERVED ACROSS COASTAL AREAS.  
 
FOR THE REST OF THIS AFTERNOON, ISOLATED THUNDERSTORMS ARE EXPECTED  
TO CONTINUE MAINLY OVER PORTIONS OF WESTERN PR. GUSTY WINDS AND  
LIGHTNING STRIKES ARE EXPECTED WITH THIS ACTIVITY. FOR TONIGHT  
INTO TUESDAY MORNING, QUICK PASSING SHOWERS ARE EXPECTED TO LEAVE  
MINOR RAINFALL AMOUNTS ACROSS THE USVI AND WINDWARD SECTIONS OF  
PR. A BROAD RIDGE BUILDING FROM THE CENTRAL ATLANTIC WILL PROMOTE  
EAST TO SOUTHEAST WINDS FOR THE NEXT FEW DAYS. A WIND SURGE WILL  
BRING SCATTERED SHOWERS AND STRONGER WINDS ACROSS THE AREA FROM  
TUESDAY NIGHT THROUGH WEDNESDAY. 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...THURSDAY THROUGH MONDAY  
 
/FROM PREV DISCUSSION ISSUED AT 500 AM AST MON JUL 7 2025/  
 
A WEAK TROPICAL WAVE IS EXPECTED TO MOVE THROUGH THE REGION ON  
THURSDAY, STEERED BY A STRONG BERMUDA-AZORES HIGH, MAINTAINING  
NEAR-NORMAL MOISTURE LEVELS. A SURFACE WIND SURGE WILL ARRIVE ON  
FRIDAY, INITIALLY ENHANCING LOW-LEVEL MOISTURE BEFORE A  
SIGNIFICANTLY DRIER AIR MASS SETTLES IN THROUGH THE WEEKEND. MID-  
TO UPPER-LEVEL DRY AIR AND A TRADE WIND CAP INVERSION—REINFORCED  
BY A TROPICAL UPPER-TROPOSPHERIC TROUGH (TUTT) TO THE  
NORTHEAST—WILL LIMIT DEEP CONVECTION DURING THIS PERIOD. MORE  
FAVORABLE CONDITIONS ARE LIKELY SUNDAY INTO EARLY NEXT WEEK AS THE  
TUTT SHIFTS OVER HISPANIOLA AND EASTERLY TRADE WIND DISTURBANCES  
APPROACH THE AREA.  
 
LINGERING MOISTURE WILL SUPPORT ISOLATED TO SCATTERED SHOWERS  
EARLY IN THE PERIOD, WITH SIGNIFICANT DRYING EXPECTED FROM FRIDAY  
THROUGH SUNDAY, REDUCING RAINFALL POTENTIAL. EVEN DURING THE  
DRIEST PERIODS, AFTERNOON CONVECTIVE DEVELOPMENT—DRIVEN BY DIURNAL  
HEATING AND LOCAL TERRAIN EFFECTS—REMAINS LIKELY EACH DAY. BREEZY  
TO WINDY CONDITIONS WILL PREVAIL THROUGH THE WEEKEND, WITH  
SOUTHEASTERLY WINDS SUPPORTING ABOVE-NORMAL TEMPERATURES,  
ESPECIALLY BETWEEN THURSDAY AND SATURDAY, WHEN VALUES ARE FORECAST  
TO EXCEED TYPICAL SEASONAL THRESHOLDS. COOLER AIR ALOFT MAY  
ARRIVE FRIDAY AND PERSIST INTO SATURDAY; HOWEVER, LIMITED MOISTURE  
WILL LIKELY PREVENT WIDESPREAD CONVECTION. RAIN CHANCES ARE  
EXPECTED TO INCREASE AGAIN FROM SUNDAY AFTERNOON INTO MONDAY.  
 
A SAHARAN AIR LAYER SPREADING OVER THE REGION BEGINNING THURSDAY  
WILL CONTRIBUTE TO HAZY SKIES, REDUCED VISIBILITY, AND CONTINUED  
SUPPRESSION OF WIDESPREAD CONVECTION THROUGH AT LEAST SATURDAY.  
WHILE EXCESSIVE RAINFALL IS NOT A CONCERN UNTIL SUNDAY, OTHER  
WEATHER HAZARDS—INCLUDING PERIODS OF EXCESSIVE HEAT, GUSTY WINDS,  
AND ISOLATED AFTERNOON LIGHTNING—REMAIN POSSIBLE THROUGHOUT THE  
LONG-TERM PERIOD.  
 
 
   
AVIATION  
 
(18Z TAFS)  
 
MAINLY VFR CONDITIONS ARE EXPECTED ACROSS ALL TERMINALS DURING  
THE NEXT 24 HOURS. HOWEVER, SHRA/TSRA EXPECTED TO DEVELOP IN AND  
AROUND TJPS/TJBQ THRU 07/22Z. ACROSS THE USVI TERMINALS AND TJSJ,  
MOSTLY VCSH EXPECTED WITH BRIEF PERIODS OF -RA. THE 07/12Z TJSJ  
SOUNDING INDICATED E-ESE WINDS UP TO 23 KT BLO FL060.  
 
 
   
MARINE  
 
MODERATE TO LOCALLY FRESH WINDS WILL CREATE CHOPPY SEAS ACROSS LOCAL  
WATERS OVER THE NEXT SEVERAL DAYS, PROMPTING CAUTION FOR SMALL CRAFT  
OPERATORS. AFTERNOON THUNDERSTORMS MAY IMPACT COASTAL WATERS AND  
LOCAL PASSAGES, PARTICULARLY OVER WESTERN PUERTO RICO AND THE MONA  
PASSAGE EACH DAY. SHOWERS AND THUNDERSTORM CHANCES INCREASE ON  
THURSDAY WITH THE PASSAGE OF A TROPICAL WAVE. SAHARAN DUST IS  
EXPECTED TO RETURN LATER IN THE WORKWEEK.  
 
 
   
BEACH FORECAST  
 
INCREASING WINDS OVER THE NEXT SEVERAL DAYS WILL PROMOTE A  
MODERATE RISK OF RIP CURRENTS ACROSS THE EASTERN, NORTHERN, AND  
SOUTHERN BEACHES OF PUERTO RICO, AND ST. CROIX. LIFE-THREATENING  
RIP CURRENTS OFTEN OCCUR IN THE VICINITY OF GROINS, JETTIES,  
REEFS, AND PIERS.  
 
 
   
SJU WATCHES/WARNINGS/ADVISORIES  
 
PR...NONE.  
VI...NONE.  
AM...NONE.  
 
 
 
 
DSR/GRS  
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