An upper level shortwave trough moved through southwesterly flow over Texas. This disturbance provided sufficient lift to initiate isolated convection.
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Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS EWX wrote it up.
An upper level shortwave trough moved through southwesterly flow over Texas. This disturbance provided sufficient lift to initiate isolated convection. Some of these storms produced weak tornadoes, large hail, and heavy rain.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Austin/San Antonio, TX wrote its last area forecast discussion before the first event at May 27, 9:14 AM CST, 25 minutes earlier.
AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX 1014 AM CDT WED MAY 27 2015 .UPDATE... CONVECTION CONTINUES ALONG A SURFACE/OUTFLOW BOUNDARY THAT SITS ACROSS THE NORTHERN HILL COUNTRY. NOT EXPECTING FOR THIS BOUNDARY TO PUSH FURTHER TO THE SOUTH REST OF TODAY WHILE STORMS CONCENTRATE ALONG AND NORTHEAST OF A FREDERICKSBURG TO KENDALIA TO HALLETTSVILLE LINE. SOME OF THESE STORMS COULD PRODUCE HEAVY RAIN AT TIMES...WHICH WILL LEAD TO FLASH FLOODING DUE TO SATURATED GROUNDS ACROSS OUR AREA. LATER THIS EVENING...ANOTHER OUTFLOW BOUNDARY IS EXPECTED TO AFFECT THE HILL COUNTRY AS AN MCS FORM ACROSS CENTRAL TEXAS AND MOVES TO THE SOUTHEAST. THIS COULD END UP ON ADDITIONAL FLASH FLOOD POTENTIAL ACROSS SOME AREAS OVER THE HILL COUNTRY. IN ADDITION...ISOLATED STRONG STORMS ARE EXPECTED TO FORM THIS AFTERNOON AND EVENING ACROSS THE MEXICAN MOUNTAINS AND SLOWLY PUSH TO THE NORTHEAST ACCORDING TO STORM MOTION. ISOLATED HEAVY RAIN IS POSSIBLE ACROSS SOME AREAS AND MINOR FLASH FLOODING CANT BE RULED OUT. && .PREV DISCUSSION... /ISSUED 648 AM CDT WED MAY 27 2015/ AVIATION... ONLY SAT REACHED IFR THIS MORNING AND ALL THE OTHER TERMINALS ARE MVFR. CIGS SHOULD STAY STEADY FOR MOST OF THE FIRST PERIOD...ALTHOUGH THERE IS SOME CHANCE OF SSF DROPPING TO IFR. THERE ARE SCATTERED SHOWERS AND THUNDERSTORMS AROUND THE REGION THIS MORNING AND THERE IS CHANCE OF THESE AT AUS. HAVE NOT INCLUDED ANY PRECIP IN THE TAF AND ANY SHOWER THAT MOVES OVER THE TERMINAL WILL NOT CHANGE THE FLYING CATEGORY. CIGS SHOULD IMPROVE TO VFR BY AROUND NOON AT ALL AIRPORTS. LOOKING FOR A REPEAT OVERNIGHT TONIGHT WITH ALL TERMINALS GOING MVFR AND THE AUSTIN AND SAN ANTONIO AIRPORTS DROPPING TO IFR. PREV DISCUSSION... /ISSUED 408 AM CDT WED MAY 27 2015/ SHORT TERM (TODAY THROUGH THURSDAY)... A CLUSTER OF STORMS WAS MOVING THROUGH THE NORTHERN I35 CORRIDOR IN MAINLY WILLIAMSON...LEE...AND FAYETTE COUNTIES THIS MORNING PRODUCING SOME MODERATE TO BRIEFLY HEAVY RAINFALL. AREA SOUNDINGS WERE SHOWING STABILIZATION AND MID LEVEL WARMING WHICH HAS EFFECTIVELY LIMITED THE CONVECTIVE POTENTIAL IN THESE STORMS FOR THE REST OF THE MORNING. AS THE UPPER SHORTWAVE RESPONSIBLE FOR THIS ACTIVITY MOVES OFF...THIS ENERGY SHOULD SHIFT SOUTHEAST BRUSHING THE EASTERNMOST ZONES THROUGH MID DAY. THE PROGRESSIVE NATURE OF THE SYSTEM SHOULD KEEP FLASH FLOODING CONCERNS LOW. FOR THE REST OF THE DAY...HI RES MODELS ALL HAVE BEEN HANDLING THE NEXT 24 HOURS RATHER POORLY AS NONE OF THEM ADEQUATELY CAPTURED THE OVERNIGHT MCS. SO NOT MUCH STOCK WAS PUT INTO THEIR DEPICTIONS. HOWEVER...PLENTY OF INSTABILITY REMAINS FOR A MORE ISOLATED STORM THREAT TODAY ACROSS THE AREA. ECMWF AND GFS INDICATED MORE MINOR SHORTWAVE PASSAGES OVER THE NEXT 24 HOURS...WITH ONE UP NEAR FORT WORTH AND YET ANOTHER OVER THE BIG BEND. WITH THE DRY LINE RECEDING WESTWARD IN THE MODELS...THINK OUTFLOWS WILL BE THE DECIDER FOR CI THIS AFTERNOON/EVENING. ONE SUCH OUTFLOW WAS OBSERVED ALONG THE RIO GRANDE THIS MORNING AND AM A BIT CONCERNED SOME DEVELOPMENT MAY OCCUR ALONG IT TODAY SO INCREASED POPS TO CHANCE OUT THERE AS WELL. LONG TERM (THURSDAY NIGHT THROUGH TUESDAY)... A MORE POTENT SHORTWAVE IS EXPECTED TO DEVELOP OFF THE NEW MEXICAN ROCKIES AND INTERACT WITH THE DRYLINE OUT WEST TO DEVELOP A MORE ORGANIZED STORM SYSTEM THURSDAY NIGHT. THERE IS PRETTY GOOD MODEL AGREEMENT THAT SOME ISOLATED CONVECTION IN THE AFTERNOON...POSSIBLY SEVERE...COULD ORGANIZE INTO A STRONG LINE OF STORMS THAT WOULD MOVE SOUTHEAST INTO THE PLATEAU COUNTIES OVERNIGHT THURSDAY. WITH PWAT VALUES IN THE 1.6-1.7 RANGE...THINK THESE COULD BE ANOTHER POTENTIAL HEAVY RAINER. GOOD NEWS IS THIS SYSTEM LOOKS RATHER PROGRESSIVE AND SHOULD BE LOSING INTENSITY AS IT DISPLACES FROM THE MAIN UPPER LEVEL SHORTWAVE ENERGY. MOVING INTO THE WEEKEND AND EARLY NEXT WEEK...A MUCH LESS ACTIVE PERIOD IS EXPECTED TO BEGIN WHEN COMPARED TO...WELL...MAY. THE JUNE 1 ECMWF SYNOPTIC PATTERN SHOWS A BUILDING RIDGE OVER THE FOUR CORNERS REGION AND KEEPS THE UPPER JET STREAM WELL TO OUR NORTH THROUGH NEXT WEEK. WE STILL HAVE PLENTY OF MOISTURE AND INSTABILITY TO WARRANT ISOLATED SHOWERS AND STORMS...BUT ORGANIZED SYSTEMS LIKE WE HAVE BEEN SEEING OVER THE LAST MONTH...LOOKS MUCH LESS LIKELY. WE AS METEOROLOGISTS ENJOY INTERESTING PATTERNS AND CHALLENGING FORECASTS TO A DEGREE. BUT WE WILL BE JOINING YOU IN A COLLECTIVE HALLELUJAH IF THINGS ARE MORE BENIGN FOR THE EXTENDED GIVEN THE LAST MONTH AND ESPECIALLY THE LAST WEEKEND. LUCKILY THAT SEEMS TO BE THE CASE FOR NOW. && .PRELIMINARY POINT TEMPS/POPS... AUSTIN CAMP MABRY 88 71 86 71 84 / 40 20 30 40 40 AUSTIN BERGSTROM INTL AIRPORT 88 70 86 71 84 / 40 20 30 40 40 NEW BRAUNFELS MUNI AIRPORT 89 73 87 72 85 / 30 20 30 30 40 BURNET MUNI AIRPORT 86 70 84 68 82 / 30 30 30 40 30 DEL RIO INTL AIRPORT 89 74 88 68 87 / 30 30 40 50 30 GEORGETOWN MUNI AIRPORT 87 71 85 70 84 / 40 30 30 40 40 HONDO MUNI AIRPORT 88 73 87 69 85 / 20 20 40 40 30 SAN MARCOS MUNI AIRPORT 88 72 85 71 83 / 30 20 30 30 40 LA GRANGE - FAYETTE REGIONAL 88 73 87 73 85 / 30 20 40 30 40 SAN ANTONIO INTL AIRPORT 89 74 86 72 85 / 20 20 30 40 40 STINSON MUNI AIRPORT 89 74 87 73 85 / 20 20 30 30 40 && .EWX WATCHES/WARNINGS/ADVISORIES... NONE. && MESOSCALE/AVIATION...76 SYNOPTIC/GRIDS...17 PUBLIC SERVICE/DATA COLLECTION...TREADWAY
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX 520 AM CDT WED MAY 27 2015 TXZ171>173-183>194-202>209-217>225-228-281030- LLANO-BURNET-WILLIAMSON-VAL VERDE-EDWARDS-REAL-KERR-BANDERA- GILLESPIE-KENDALL-BLANCO-HAYS-TRAVIS-BASTROP-LEE-KINNEY-UVALDE- MEDINA-BEXAR-COMAL-GUADALUPE-CALDWELL-FAYETTE-MAVERICK-ZAVALA- FRIO-ATASCOSA-WILSON-KARNES-GONZALES-DE WITT-LAVACA-DIMMIT- 520 AM CDT WED MAY 27 2015 THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTH CENTRAL TEXAS. .DAY ONE...TODAY AND TONIGHT. RIVER FLOODING WILL CONTINUE TODAY AND TONIGHT. ANY RAIN TODAY SHOULD NOT AFFECT RIVER LEVELS SIGNIFICANTLY. .DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY. RIVER FLOODING WILL CONTINUE AT LEAST THROUGH THE END OF THE WEEK. THERE IS A CHANCE FOR THUNDERSTORMS PRODUCING LOCALLY HEAVY RAIN THURSDAY AND THURSDAY NIGHT MAINLY OVER THE WESTERN PART OF THE AREA. OTHERWISE NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION MAY BE NEEDED THURSDAY AND THURSDAY NIGHT.
The Austin/San Antonio radar (KEWX), 57 km away, was scanning. The volume nearest the first event began at 15:40 UTC.
1 hail, 1 flash flood, 1 tornado. Local standard time, as filed.
A thunderstorm produced quarter sized hail at the intersection of Slaughter Ln. and Escarpment Blvd. in Austin.
Thunderstorms produced heavy rain that led to flash flooding closing low water crossings on Joe Tanner Ln. and Old Bee Caves Rd.
A thunderstorm produced a brief, weak tornado just east of Hwy 281 near the Little Blanco River. No damage was reported.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Texas in 2015Every state in 2015This day in weather historyThe tornado archive for Texas, 2015Warnings in Texas, May 2015
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 581115, 581120, 581123.