597  
FXUS64 KHGX 202312  
AFDHGX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX  
612 PM CDT MON JUL 20 2026  
   
..NEW AVIATION
 
 
   
KEY MESSAGES
 
 
- HOT CONDITIONS PERSIST THROUGH THE WEEK WITH THE HOTTEST DAYS  
TUESDAY AND WEDNESDAY.  
 
- A HEAT ADVISORY IS IN EFFECT FROM 11 AM - 8 PM TUESDAY.  
 
- NHC IS MONITORING THE DEVELOPMENT OF TROPICAL DEPRESSION TWO,  
CURRENTLY IN THE NORTHEAST GULF. WHILE FORECAST UNCERTAINTY  
REMAINS FAIRLY HIGH, RESIDENTS SHOULD MONITOR THE LATEST  
FORECASTS AND EVOLUTION OF THIS SYSTEM.  
 
- CORRESPONDING RAIN AND TEMPERATURE FORECASTS FOR THE LOCAL AREA  
ARE SUBJECT TO CHANGES LATER IN THE WEEK AND HIGHLY DEPENDENT ON  
THE TROPICS.  
 

 
   
DISCUSSION
 
 
ISSUED AT 225 PM CDT MON JUL 20 2026  
 
HOT AND HUMID CONDITIONS CONTINUE THIS AFTERNOON AS HIGH PRESSURE  
REMAINS ANCHORED OVER THE REGION. WATER VAPOR AND VISIBLE SATELLITE  
IMAGERY DEPICT A PREVAILING DRIER AIRMASS AND BROAD SUBSIDENCE  
DOMINANT ACROSS THE AREA. AFTERNOON TEMPERATURES WILL CLIMB INTO THE  
MID 90S. WHEN COMBINED WITH SFC DEWPOINTS IN THE 70S, HEAT INDICES  
WILL REACH UP TO 107F, CLOSE TO ADVISORY LEVELS. BE SURE TO  
PRACTICE HEAT SAFETY IF SPENDING EXTENDED PERIODS OUTDOORS!  
 
THE MAIN WEATHER STORY FOR THE FIRST HALF OF THE WEEK CONTINUES TO  
BE THE HEAT. A ROBUST RIDGE OF HIGH PRESSURE WILL REMAIN ANCHORED  
ACROSS THE CENTRAL AND WESTERN CONUS, PROVIDING SUFFICIENT  
SUBSIDENCE LOCALLY TO KEEP HIGHS ON A STEADY UPWARD TREND. SOME  
INLAND LOCATIONS WILL LIKELY SEE THEIR FIRST 100-DEGREE DAY OF THE  
YEAR BY TUESDAY OR WEDNESDAY. SIMULTANEOUSLY, LOW TO MID-LEVEL  
MOISTURE FILTERING INLAND FROM THE GULF WILL KEEP HUMIDITY LEVELS  
ELEVATED. THE COMBINATION OF HOT AND HUMID CONDITIONS WILL PUSH PEAK  
HEAT INDEX VALUES INTO THE 107 TO 112F RANGE TUESDAY AND WEDNESDAY.  
A HEAT ADVISORY HAS BEEN ISSUED FOR ALL OF SOUTHEAST TEXAS FOR  
TUESDAY FROM 11 AM - 8 PM. WEDNESDAY IS SHAPING UP TO BE EVEN HOTTER  
(LIKELY DUE TO THE APPROACHING TROPICAL SYSTEM OVER THE GULF).  
THEREFORE, ADVISORIES WILL LIKELY BE EXTENDED IN FUTURE FORECAST  
UPDATES.  
 
HEADING INTO THURSDAY - SATURDAY, ATTENTION TURNS TOWARD THE GULF  
REGARDING THE EVOLUTION OF TROPICAL DEPRESSION (TD)TWO. THE MID TO  
UPPER LEVEL RIDGE POSITIONED TO OUR NORTHWEST WILL SERVE AS THE  
PRIMARY STEERING FOCUS, NUDGING THE SYSTEM ON A GENERAL WESTWARD TO  
WEST-NORTHWESTWARD TRACK TOWARD THE NORTHWESTERN GULF. HOWEVER,  
ENVIRONMENTAL FACTORS INCLUDING DRY AIR ENTRAINMENT AND SHEAR  
COULD INFLUENCE THE SYSTEM'S TRACK AND INTENSITY. PLEASE, SEE THE  
TROPICAL DISCUSSION BELOW FOR FURTHER DETAILS ON THIS SYSTEM AND  
POTENTIAL IMPACTS FOR SOUTHEAST TEXAS.  
 
FORECAST BEYOND SATURDAY REMAINS SENSITIVE TO THE FINAL TRACK AND  
STRENGTH OF TD TWO. WELL-ABOVE NORMAL TEMPERATURES WILL BE POSSIBLE.  
WILL CONTINUE TO MONITOR FOR HEAT HEADLINES THROUGH THE WEEKEND.  
 
JM  
 

 
   
AVIATION
 
 
(00Z TAF ISSUANCE)  
ISSUED AT 611 PM CDT MON JUL 20 2026  
 
VFR CONDITIONS AND LIGHT WINDS WILL PREVAIL. WINDS WILL TRANSITION  
FROM THE SSW THIS EVENING, TO THE WSW OVERNIGHT INTO EARLY  
AFTERNOON, THEN BACK TO THE SW/SSW LATE IN THE DAY). THERE WAS  
SOME PATCHY FOG AROUND EARLIER THIS MORNING, BUT FCST SOUNDINGS  
SHOW A BIT DRIER LLVL CONDITIONS...SO OTHER THAN SOME RURAL  
LOCATIONS MAINLY WEST OF I-45, MOST TERMINALS SHOULDN'T SEE  
SIGNIFICANT VSBY DROPS. 47  
 

 
   
MARINE
 
 
ISSUED AT 225 PM CDT MON JUL 20 2026  
 
SURFACE HIGH PRESSURE WILL CONTINUE TO BRING LIGHT TO OCCASIONALLY  
MODERATE WEST TO SOUTHWEST WINDS AND LOW SEAS ACROSS THE UPPER TX  
COAST. MARINERS SHOULD CONTINUE TO MONITOR WEATHER CONDITIONS,  
ESPECIALLY TOWARD THE END OF THE WEEK AS TROPICAL DEPRESSION TWO  
MOVES WESTWARD ALONG THE NORTHERN GULF. THIS SYSTEM IS FORECAST TO  
STRENGTHEN INTO A TROPICAL STORM LATER TODAY AS IT APPROACHES  
SOUTHEAST LOUISIANA, BEFORE WEAKENING AGAIN INTO A TROPICAL  
DEPRESSION AS IT MOVES TOWARD THE UPPER TEXAS COAST THURSDAY AND  
FRIDAY. WHILE FORECAST CONFIDENCE REMAINS LOW, GIVEN HIGH  
UNCERTAINTY IN TRACK AND INTENSITY; SIGNIFICANT IMPACTS ARE NOT  
ANTICIPATED ACROSS OUR COASTAL WATERS. HOWEVER, SMALL CRAFT  
ADVISORIES COULD POTENTIALLY BE ISSUED DURING THIS PERIOD WITH  
ELEVATED WINDS AND SEAS UP TO 6 FT (OFFSHORE).  
 
JM  
 

 
   
TROPICAL
 
 
ISSUED AT 329 PM CDT MON JUL 20 2026  
 
AS OF 3 PM CDT, TROPICAL DEPRESSION TWO CONTINUES TO MEANDER  
SLOWLY NORTHWESTWARD IN THE NORTHEASTERN GULF. THE SYSTEM HAS  
BECOME BETTER ORGANIZED RELATIVE TO YESTERDAY, FEATURING AN  
INCREASE IN BANDING FEATURES AS WELL AS AN UPTICK IN DEEP  
CONVECTION NEAR, THOUGH NOT COMPLETELY COLLOCATED, WITH THE  
CENTER. MODERATE UPPER-LEVEL SHEAR AND DRY AIR CONTINUE TO LIMIT  
THE RATE OF FURTHER ORGANIZATION. HOWEVER, THESE CONDITIONS ARE  
NOT EXPECTED TO PREVENT STRENGTHENING. THEREFORE, THE DEPRESSION  
IS FORECAST TO BECOME A TROPICAL STORM LATER TONIGHT OR TOMORROW  
AS IT CONTINUES ITS SLOW, NORTHWESTWARD DRIFT.  
 
BY WEDNESDAY, A BUILDING RIDGE IS EXPECTED TO STEER THE SYSTEM  
WESTWARD, PLACING IT ON A TRAJECTORY TOWARDS SOUTHEAST TEXAS. THE  
PRIMARY METEOROLOGICAL QUESTION FOR OUR AREA WILL BE WHETHER OR  
NOT THE SYSTEM CAN SURVIVE THE ATMOSPHERIC AND GEOGRAPHICAL  
HURDLES THAT LIE AHEAD OF IT. FOR STARTERS, THE SYSTEM IS EXPECTED  
TO TRACK NEAR OR OVER SOUTHERN LOUISIANA, LIMITING ITS  
INTENSIFICATION DUE TO LAND INTERACTION. IN ADDITION, THE  
BUILDING RIDGE WILL INCREASINGLY SUPPLY NORTH TO NORTHEASTERLY  
WIND SHEAR. THIS WOULD TEND TO DECOUPLE THE MID-LEVEL CIRCULATION  
FROM THE LOWER LEVELS, WEAKENING THE SYSTEM AS IT APPROACHES  
SOUTHEAST TEXAS. THERE'S ALSO THE CURRENT ENTRAINMENT OF DRY AIR,  
WHICH COUPLED WITH THE SHEAR IS RESULTING IN AN EXPOSED CENTER  
THAT IS NOT COLLOCATED WITH THE DEEP CONVECTION.  
 
DUE TO THESE ENVIRONMENTAL FACTORS, THE NATIONAL HURRICANE CENTER  
IS PREDICTING THAT THE SYSTEM WILL WEAKEN BACK TO A DEPRESSION AS  
IT APPROACHES SOUTHEAST TEXAS TOWARDS THE END OF THE WEEK. THAT  
BEING SAID, WE CONTINUE TO STRONGLY ADVISE THE PUBLIC TO MONITOR  
THE FORECAST IN CASE TRENDS CHANGE.  
 
SELF  
 

 
   
PRELIMINARY POINT TEMPS/POPS
 
 
COLLEGE STATION (CLL) 72 98 78 100 / 0 0 0 0  
HOUSTON (IAH) 75 100 80 102 / 0 0 0 10  
GALVESTON (GLS) 79 94 81 95 / 0 0 0 10  
 

 
   
HGX WATCHES/WARNINGS/ADVISORIES
 
 
TX...HEAT ADVISORY FROM 11 AM TO 8 PM CDT TUESDAY FOR TXZ163-164-  
176>179-195>200-210>214-226-227-235>238-300-313-335>338-  
436>439.  
 
GM...NONE.  
 

 
 

 
 
DISCUSSION...JM  
AVIATION...47  
MARINE...JM  
 
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