619  
FXUS64 KEWX 121742  
AFDEWX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX  
1242 PM CDT SUN APR 12 2026  
   
..NEW AVIATION  
 
   
KEY MESSAGES  
 
 
- A LINE OF STORMS WILL CONTINUE ACROSS THE ACROSS THE HILL  
COUNTRY TOWARDS THE I-35 CORRIDOR EARLY SUNDAY MORNING, WITH HEAVY  
DOWNPOURS AND ISOLATED SEVERE WEATHER POSSIBLE.  
 
- ISOLATED STRONG TO SEVERE STORMS WITH HEAVY DOWNPOURS ARE  
POSSIBLE THIS AFTERNOON AND EVENING ACROSS SOUTH-CENTRAL TEXAS.  
 
- THE POTENTIAL FOR STRONG TO SEVERE STORMS AND LOCALLY HEAVY  
RAINFALL CONTINUES THROUGH THE WEEKEND INTO EARLY NEXT WEEK.  
 
 
   
UPDATE  
 
ISSUED AT 1037 AM CDT SUN APR 12 2026  
 
A FLOOD WATCH IS NOW IN EFFECT FOR THE I-35 CORRIDOR AND COASTAL  
PLAINS THAT GOES THROUGH TOMORROW MORNING. A HEAVY RAIN SIGNAL  
CONTINUES TO INCREASE CONFIDENCE IN POTENTIAL FLOODING FOR AREAS  
IN THE WATCH THIS AFTERNOON THROUGH TONIGHT.  
 
 
   
SHORT TERM  
 
(TODAY THROUGH MONDAY)  
ISSUED AT 136 AM CDT SUN APR 12 2026  
 
AS OF 1 AM CDT SUNDAY, A LINE OF STRONG TO MARGINALLY SEVERE  
THUNDERSTORMS WAS MOVING ACROSS THE SOUTHERN EDWARDS PLATEAU AND  
HILL COUNTRY. IT WILL CONTINUE TO ADVANCE ACROSS THE HILL COUNTRY  
AND PORTIONS OF THE I-35 CORRIDOR (MAINLY NEAR THE AUSTIN AREA)  
EARLY THIS MORNING. THE PRIMARY CONCERN, GIVEN THE VERY MOIST  
AIRMASS IN PLACE, IS LOCALLY HEAVY DOWNPOURS WITH THE POTENTIAL FOR  
ISOLATED INSTANCES OF FLASH FLOODING. A RESIDUAL ISOLATED DAMAGING  
WIND THREAT IS ALSO POSSIBLE AND UNDERLIES THE CURRENTLY ACTIVE  
SEVERE THUNDERSTORM WATCHES. HOWEVER, THAT RISK THAT SHOULD  
GENERALLY DECLINE DURING THE MORNING AS THE STORMS MOVE FARTHER EAST  
AND START TO LOSE THEIR DEFINITION AMID STABILIZING AIR.  
 
THE FORECAST DURING THE DAY SUNDAY IS MORE UNCERTAIN THAN USUAL. THE  
MORNING STORMS ARE EXPECTED TO CONSUME SOME OF THE INSTABILITY OVER  
SOUTH-CENTRAL TEXAS AND INTRODUCE SLIGHT CAPPING. HOWEVER, THE  
STORMS MAY LEAVE A SURFACE BOUNDARY DRAPED ACROSS OUR AREA, AND THE  
PERSISTENCE OF A WARM AND MOIST AIRMASS WILL ALLOW INSTABILITY TO  
BUILD THROUGHOUT THE DAY, ESPECIALLY ALONG AND WEST OF THE I-35  
CORRIDOR. ISOLATED TO SCATTERED SHOWERS MAY CONTINUE THROUGH THE  
MORNING INTO THE AFTERNOON. IF UPDRAFTS PUNCH CLEANLY THROUGH THE  
CAP, PARTICULARLY ON THE LEFTOVER OUTFLOW BOUNDARY, THERE COULD BE A  
FEW ISOLATED THUNDERSTORMS WITH ACCOMPANYING HEAVY RAIN. NOT ALL OF  
THE HIGH RESOLUTION MODELS DEPICT THESE STRONGER STORMS IN THE  
AFTERNOON, BUT THOSE THAT DO FAVOR THE I-35 CORRIDOR AND HILL  
COUNTRY. GIVEN VERY HIGH MOISTURE LEVELS FOR THIS TIME OF YEAR AND  
FAVORABLE ATMOSPHERIC PROFILES, EVEN RELATIVELY SMALL SHOWERS CAN  
STILL BE HIGHLY EFFICIENT RAINMAKERS. EVEN WITH THE RELATIVELY LOW  
CONFIDENCE IN STORM COVERAGE, THE PRESENCE OF A LEVEL 2 OF 4  
(SLIGHT) RISK OF EXCESSIVE RAINFALL CAPABLE OF CAUSING FLASH  
FLOODING UNDERSCORES THE ANOMALOUS MOISTURE AVAILABLE TO ANY SHOWERS  
THAT DEVELOP SUNDAY. BASED ON THIS ENVIRONMENT, THIS IS OUR MAIN  
CONCERN WITH TODAY'S STORMS.  
 
TOWARDS THE EVENING HOURS AND INTO SUNDAY NIGHT, SUFFICIENT HEATING  
OVER MEXICO AND A SUBTLE SHORTWAVE MOVING ACROSS THE RIO GRANDE MAY  
PROMPT THE DEVELOPMENT THUNDERSTORMS. HOWEVER, IT IS UNCLEAR WHETHER  
THESE WILL ALSO EXTEND INTO THE RIO GRANDE PLAINS AND SOUTHERN  
EDWARDS PLATEAU. IF THEY DO, THE PRESENCE OF MODERATELY STRONG WIND  
SHEAR (30-40 KT BULK SHEAR) AND HIGH INSTABILITY (ABOVE 2000 J/KG  
CAPE) COULD SUPPORT SEVERE STORMS, WITH LARGE HAIL THE PRIMARY  
HAZARD. THIS POTENTIAL IS ENCAPSULATED IN THE LEVEL 2 OF 5 (SLIGHT)  
RISK FOR SEVERE WEATHER HIGHLIGHTED BY THE SPC FOR AREAS GENERALLY  
ALONG AND WEST OF THE I-35 CORRIDOR. HOWEVER, MUCH LIKE THE ACTIVITY  
EARLIER ON SUNDAY, THE OCCURRENCE OF THIS ACTIVITY IS HIGHLY  
SENSITIVE TO PRECEDING DEVELOPMENTS. MOST OF THE HI-RES MODELS SHOW  
VERY SPARSE STORM COVERAGE SUNDAY EVENING, WHILE THE COARSER  
SYNOPTIC-SCALE MODELS AND MACHINE LEARNING MODELS FAVOR MORE RAIN  
COVERAGE. WE'LL LIKELY HAVE A BETTER HANDLE ON THIS ACTIVITY ONCE  
WE'RE ABLE TO ASSESS HOW THE CURRENT LINE OF STORMS IMPACTS THE  
ATMOSPHERIC ENVIRONMENT.  
 
PRECIPITABLE WATER LEVELS EASE SLIGHTLY ON MONDAY, BUT NONETHELESS  
IT WILL REMAIN MOIST WITH PW ABOVE THE 90TH PERCENTILE. STRONGER  
CAPPING IS EXPECTED TO BE IN PLACE, AND SHOULD GENERALLY LIMIT  
SHOWER COVERAGE. STILL, A FEW THUNDERSTORMS COULD DEVELOP ALONG THE  
DRY LINE IN WEST TEXAS, WHICH COULD PRODUCE ISOLATED SEVERE ACTIVITY  
IN THE SOUTHERN EDWARDS PLATEAU MONDAY EVENING.  
 
 
   
LONG TERM  
 
(MONDAY NIGHT THROUGH SATURDAY)  
ISSUED AT 136 AM CDT SUN APR 12 2026  
 
THE BROAD UPPER-LEVEL TROUGHING PATTERN HELPING TO SHAPE OUR  
UNSETTLED WEATHER PERSISTS THROUGH NEXT WEEK, ALONG WITH THE WARM  
AND MOIST AIRMASS OVER TEXAS. SOUTHWESTERLY FLOW ALOFT WILL PROVIDE  
CONTINUED CHANCES FOR SHOWERS AND THUNDERSTORMS MOST DAYS, TYPICALLY  
IN THE AFTERNOON AND EARLY EVENING IN TANDEM WITH DAYTIME HEATING.  
GIVEN THE ANOMALOUS AIRMASS, STRONG STORMS WITH LOCALLY HEAVY  
RAINFALL WILL ALSO BE POSSIBLE THROUGHOUT THE WEEK.  
 
AROUND MIDWEEK, A STRONGER SHORTWAVE ASSOCIATED WITH THE BROADER  
PATTERN SWINGS EAST INTO THE CENTRAL PLAINS, ACCOMPANIED BY A ROUND  
OF STRONGER STORMS OVER THE CENTRAL US. WHILE THE TRAJECTORY OF THIS  
TROUGH WILL TEND TO KEEP THE WORST WEATHER FARTHER NORTH, SOME  
STRONGER STORMS COULD EXTEND INTO OUR AREA SOMETIME TUESDAY OR  
WEDNESDAY. SOUTHWESTERLY MID- TO UPPER-LEVEL FLOW CONTINUES THROUGH  
THE REMAINDER OF THE WEEK, THOUGH THE LACK OF WELL-DEFINED  
SHORTWAVES DURING THE LATTER HALF OF THE WEEK MAY LIMIT THE  
POTENTIAL FOR STRONGER STORMS AND KEEP SHOWERS MORE ISOLATED  
COMPARED TO WHAT WE'VE BEEN SEEING THE PAST FEW DAYS.  
 
OVERNIGHT TEMPERATURES WILL BE RELATIVELY STABLE THROUGH THE WEEK,  
BUOYED INTO THE 60S AND LOW 70S BY HIGH DEW POINTS. DAYTIME HIGHS  
WILL GENERALLY BE IN THE 80S, BUT COULD WARM SOME INTO THE LOW 90S  
LATE NEXT WEEK DURING SLIGHTLY CALMER STRETCHES WITH LESS RAIN.  
 
 
   
AVIATION  
 
(18Z TAFS)  
ISSUED AT 1241 PM CDT SUN APR 12 2026  
 
MOSTLY MVFR CONDITIONS ARE EXPECTED TODAY, THOUGH FURTHER WEST AND  
POSSIBLY OVER KSAT/KSSF SOME PERIODS OF VFR MAY BE SEEN. SHOWERS AND  
THUNDERSTORMS, SOME OF WHICH MAY BE STRONG TO SEVERE, WILL MAINLY BE  
FOCUSED FROM THE HILL COUNTRY EAST TODAY WITH TIMING TRICKY FOR I-35  
TERMINALS. HI-RES GUIDANCE SUGGESTS A LATER TIME STORMS TO IMPACT  
TERMINALS SO PUSHED BACK TEMPO GROUPS SLIGHTLY TO ACCOUNT FOR THESE  
TRENDS. THIS EVENING, CEILINGS DROP TO IFR AND BEGIN TO SPREAD WEST  
REACHING KDRT BEFORE SUNRISE. LOCAL LIFR CEILINGS MAY BE SEEN ALONG  
WITH AREAS OF PATCHY DENSE FOG, THOUGH CONFIDENCE IS NOT HIGH ENOUGH  
TO INCLUDE THESE MENTIONS AT ANY SITE. WIND REMAINS SOUTH TO  
SOUTHEASTERLY THROUGH THE PERIOD WITH GUSTY WIND FROM 20-25 KNOTS IN  
THE EASTERN HALF OF THE AREA.  
 
 
   
PRELIMINARY POINT TEMPS/POPS  
 
AUSTIN CAMP MABRY 70 85 69 86 / 60 10 0 10  
AUSTIN BERGSTROM INTL AIRPORT 69 85 68 85 / 60 20 0 10  
NEW BRAUNFELS MUNI AIRPORT 69 86 68 86 / 50 20 10 10  
BURNET MUNI AIRPORT 67 83 67 82 / 50 10 10 20  
DEL RIO INTL AIRPORT 70 87 70 84 / 10 20 40 40  
GEORGETOWN MUNI AIRPORT 69 82 67 82 / 60 10 0 10  
HONDO MUNI AIRPORT 67 85 68 85 / 40 20 20 20  
SAN MARCOS MUNI AIRPORT 69 85 68 85 / 60 20 10 10  
LA GRANGE - FAYETTE REGIONAL 70 85 69 87 / 50 20 0 0  
SAN ANTONIO INTL AIRPORT 70 85 70 85 / 50 20 10 10  
STINSON MUNI AIRPORT 71 86 70 86 / 40 20 10 10  
 
 
   
EWX WATCHES/WARNINGS/ADVISORIES  
 
FLOOD WATCH THROUGH MONDAY MORNING FOR TXZ173-191>194-206>209-  
223>225.  
 
 
 
 
 
SHORT TERM...TRAN  
LONG TERM....TRAN  
AVIATION...27  
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