588  
FXUS64 KBRO 072338 AAA  
AFDBRO  
 
AREA FORECAST DISCUSSION...UPDATED  
NATIONAL WEATHER SERVICE BROWNSVILLE TX  
638 PM CDT TUE JUL 7 2020  
   
DISCUSSION
 
UPDATED FOR LATEST AVIATION DISCUSSION BELOW.  

 
   
AVIATION
 
MVFR TO VFR CONDITIONS ARE EXPECTED THROUGH THE NEXT  
24 HOURS. SURFACE WINDS WILL DIMINISH TONIGHT ONLY TO INCREASE  
DURING THE DAYLIGHT HOURS OF WEDNESDAY. CONVECTION IS NOT LIKELY.  

 
   
PREV DISCUSSION
 
/ISSUED 229 PM CDT TUE JUL 7 2020/  
 
SHORT TERM (NOW THROUGH WEDNESDAY NIGHT): BROWNSVILLE RADAR  
CURRENTLY SHOWS ISOLATED SHOWERS ACROSS THE SOUTHERN END OF THE  
LOWER TEXAS GULF WATERS. OTHERWISE, HOT, HUMID AND RAIN-FREE  
CONDITIONS CONTINUE ACROSS THE CWA THIS AFTERNOON. A MID-LEVEL  
WEAKNESS OVER NORTHEAST TEXAS THIS AFTERNOON AND TONIGHT WILL BE  
REPLACED BY A 500 MB RIDGE BUILDING INTO THE REGION FROM THE WEST  
ON WEDNESDAY. LOWS TONIGHT WILL BE SLIGHTLY ABOVE NORMAL IN THE  
UPPER 70S TO LOWER 80S. A FEW STREAMER SHOWERS ARE POSSIBLE OVER  
THE COASTAL WATERS OVERNIGHT. HIGH TEMPERATURES ON WEDNESDAY WILL  
RANGE FROM NEAR 90 AT THE BEACHES, MID TO UPPER 90S IN THE EAST  
AND 100 TO 106 DEGREES IN THE WEST. SLIGHTLY HIGHER HEAT INDEX  
VALUES MAY WARRANT A SHORT DURATION HEAT ADVISORY FOR PORTIONS OF  
HIDALGO AND STARR COUNTIES ON WEDNESDAY. LOW TEMPERATURES  
WEDNESDAY NIGHT WILL BE IN THE UPPER 70S TO LOWER 80S. EXCEPT FOR  
STREAMER SHOWERS NEAR THE COAST, NO RAINFALL IS EXPECTED DURING  
THE SHORT TERM.  
 
LONG TERM (THURSDAY THROUGH TUESDAY): SYNOPTIC SCALE CONDITIONS  
AFFECTING DEEP SOUTH TEXAS AND THE LOWER RGV ARE NOT EXPECTED TO  
CHANGE SIGNIFICANTLY IN THE LONG TERM PERIOD. THE MODELS TEND TO  
MAINTAIN A STRONG MID LEVEL RIDGE OVER ARIZONA/NEW MEXICO/WEST  
TEXAS/NORTH CENTRAL MEXICO THROUGH THE PERIOD. THIS WILL IN TURN  
REINFORCE SURFACE HIGH PRESSURE OVER THE GULF OF MEXICO AND THE  
ASSOCIATED GENERALLY STABLE, ANTICYCLONIC FLOW INTO THE AREA.  
INTRUSIONS OF MID LEVEL TROUGHS INTO THE SOUTHEAST UNITED STATES  
WILL AT TIMES CAUSE GULF HIGH PRESSURE TO WEAKEN OR SHIFT  
POSITION, RESULTING IN THE LOCAL VARIATION OF WIND DIRECTION,  
GENERALLY BETWEEN SOUTHEAST AND SOUTH.  
 
RAIN CHANCES WILL REMAIN VERY LOW AND SILENT IN THE FORECAST,  
WITH MOSTLY CLEAR SKIES THE MAJORITY OF THE TIME. HIGH TEMPS WILL  
REMAIN NEAR TO SLIGHTLY ABOVE NORMAL. THE INTERIOR RIDGE WILL TEND  
TO BUILD EAST OVER THE AREA A BIT MORE TOWARD THE LATTER HALF OF  
THE LONG TERM, RESULTING IN TEMPERATURES NUDGING HIGHER AND MORE  
ABOVE AVERAGE, ESPECIALLY ACROSS INLAND AREAS. THIS WILL BE  
COUNTERED IN PART BY SLIGHTLY DRIER CONDITIONS, RESULTING IN HEAT  
INDEX VALUES AVERAGING IN THE 103 TO 108 RANGE. A FEW AREAS IN THE  
STARR/ZAPATA COUNTY AREAS MAY SEE SLIGHTLY HIGHER AFTERNOON HEAT  
INDEX VALUES, ESPECIALLY THURSDAY AND FRIDAY AFTERNOONS, NEAR 110  
DEGREES.  
 
MARINE:  
 
NOW THROUGH WEDNESDAY NIGHT...A ROBUST THERMAL GRADIENT WILL  
SUPPORT MODERATE ONSHORE FLOW FOR THE REST OF THE AFTERNOON INTO  
TONIGHT. SMALL CRAFT EXERCISE CAUTION CONDITIONS IS EXPECTED TO  
CONTINUE ON THE LAGUNA MADRE THROUGH LATE THIS EVENING. THE  
PRESSURE GRADIENT IS EXPECTED TO STRENGTHEN ALONG THE LOWER TEXAS  
COAST ON WEDNESDAY AS LOW PRESSURE ACROSS WEST TEXAS INTERACTS  
WITH HIGH PRESSURE ACROSS THE GULF. A SMALL CRAFT ADVISORY MAY BE  
NEEDED ON THE LAGUNA MADRE FOR WEDNESDAY AFTERNOON. ISOLATED  
SHOWERS ARE POSSIBLE TONIGHT ON THE GULF WATERS.  
 
THURSDAY THROUGH SUNDAY NIGHT...HIGH PRESSURE WILL DOMINATE OVER  
THE CENTRAL GULF. LOWER PRESSURE OVER THE SOUTHERN HIGH PLAINS AND  
SOUTHWEST UNITED STATES WILL CONTRAST WITH THE HIGHER PRESSURE  
OVER THE GULF, SUPPORTING A MODEST PRESSURE GRADIENT THROUGH THE  
FORECAST PERIOD. LOOK FOR MODERATE TO FRESH SOUTHEAST TO SOUTH  
WINDS AND MODERATE SEAS. WINDS WILL BE STRONG ENOUGH AT TIMES TO  
SUPPORT SMALL CRAFT SHOULD EXERCISE CAUTION CONDITIONS, ESPECIALLY  
OVER THE LAGUNA MADRE AND NEARSHORE GULF WATERS.  

 
   
PRELIMINARY POINT TEMPS/POPS
 
 
BAYVIEW/PORT ISABEL 80 93 80 90 / 10 0 0 0  
BROWNSVILLE 80 96 81 93 / 10 0 0 0  
HARLINGEN 79 98 80 96 / 10 0 0 0  
MCALLEN 80 100 81 98 / 10 0 0 0  
RIO GRANDE CITY 79 104 80 102 / 10 0 0 0  
SOUTH PADRE ISLAND 81 88 83 87 / 20 0 0 0  

 
   
BRO WATCHES/WARNINGS/ADVISORIES
 
NONE.  

 
 

 
 
THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT:  
HTTP://WEATHER.GOV/RGV  
 
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