Thunderstorms formed along a cold front over Central Texas. Some of these storms moved into South-Central Texas and produced locally heavy rain that led to flash flooding.
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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.
Thunderstorms formed along a cold front over Central Texas. Some of these storms moved into South-Central Texas and produced locally heavy rain that led to flash flooding.
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 21, 5:32 PM CST, 10 minutes earlier. Its key messages:
Area Forecast Discussion National Weather Service Austin/San Antonio TX 632 PM CDT Thu May 21 2026 ...New AVIATION... .KEY MESSAGES... - Low to medium chances for rain this afternoon/evening. Isolated showers and storms may develop with the most favored areas over the southern Edwards Plateau, Rio Grande, and parts of the Hill Country. - Flood Watch Friday evening through Monday evening for areas along and east of a Kerr to Frio County line. - Active and unsettled weather pattern continues into next week. Multiple rounds of storms with heavy rain are possible and could lead to localized flooding. && .SHORT TERM... (Tonight through Friday night) Issued at 301 PM CDT Thu May 21 2026 A stalled frontal boundary along with previous outflow boundaries will be the main focus for additional thunderstorm development late this afternoon into tonight. Many areas did not receive much in the way of showers and thunderstorms last night which leads to a rather challenging and low confidence forecast for the short term portion. That being said we are starting to see clouds clearing in the western half of the area when looking at visible satellite imagery leading to the possibility of convection to form as the atmosphere begins to destabilize. SPC also has this area in a level 1 of 5 risk for severe weather with the main threats being large hail and damaging wind gusts. We are not anticipating a widespread event initially this evening but rather a more scattered to isolated scenario. Hi-Res models continue to be all over the place regarding initial placement and timing but the overall consensus is that most would see activity occur after 4 PM and continue through this evening into the overnight. An initial round of activity already located over Llano, Kimble and Mason counties will continue to progress eastward with activity continuing to form back behind it. The recent run of RRFS (18Z) shows this complex of activity slowly drifting southeastward and impacting parts of the Hill Country. The latest 18Z ACAR sounding at SAT shows MUCAPE of 1800 J/kg while the AUS sounding shows around 1600 J/kg and along with SPC meso showing mid-level lapse rates of 6.5 to 7 c/km. Any storms that do form will have the potential to produce damaging winds, large hail and torrential rainfall as moisture remains extremely high over the region. WPC has expanded their level 1 of 4 risk to include the entire area for today due to the recent rainfall and the anomalously high moisture located over our area. Several short range models show a secondary wave of activity forming over either West TX or Central TX as a another disturbance progresses eastward. This convection would then swing southward through the Rio Grande and Southern Edwards Plateau, possibly clipping portions of Bexar County and perhaps parts of the western Hill Country. However it should be weakening as it does so with most activity ending before daybreak Friday morning with most activity then pushing southward into South TX. Friday into Friday evening we seem to be in a bit of a lull as we remain trapped between two disturbances with the one moving off to our east and then the next one located over West TX and impacting portions of our western areas beginning as early as Saturday morning. Additionally due to the area receiving widespread rainfall of 1 to 3 inches over the past 3 days and the potential for additional rounds of heavy rainfall we went ahead and issued a Flood Watch for the entirety of the holiday weekend for areas along and east of a Kerr to Frio county line. && .LONG TERM... (Saturday through next Thursday) Issued at 301 PM CDT Thu May 21 2026 As alluded to above, Saturday could shape up to be a very active day as our next disturbance will be approaching the area sparking another round of showers and thunderstorms capable of very heavy rainfall as moisture continues to remain high across the area. There is relative good agreement on the latest model consensus regarding the evolution of a low pushing across our area and stalling over East TX. This low will be the focus for the repeated rounds of thunderstorms and heavy rainfall over the extended weekend. Many areas could see a widespread swath of 2 to 4 inches with some areas seeing isolated totals of up to 6 inches of rainfall especially for those across the Watch area. As such, WPC currently has our area in a level 2 of 4 risk for excessive rainfall for areas along and east of the I-10 to I-35 Corridor including the San Antonio and Austin Metro areas. Global models continue to indicate this low meandering somewhere across East TX until at least Tuesday as the upper level pattern shows another trough digging down into the Western U.S. This trough will help to finally kick out the meandering low but also puts our area back into southwest flow aloft. This then opens the door for renewed rainfall chances as disturbances continue to push across our area into next week. As stated previously this is a rather low confidence and challenging forecast as each round of storms moves across parts of our area, more stable conditions will likely follow leading to periods of dry weather as the atmosphere recharges. Even though many chances for precipitation are seen in the extended forecast, periods of dry weather are also expected. Similarly, as each day evolves, the outflow and leftover boundaries from the previous day's convection will be the continued focus for renewed development for the next day. Thus it wont be until 24 to perhaps 48 hrs prior to each day that we will be able to pinpoint the location and eventually trajectory of where storms may fire. It should be noted that every rain event that occurs will continue to bring soils closer to saturation thus increasing the potential for excessive run off which can lead to flash flooding or river flooding. Please continue to monitor the forecast and always have a way to receive warning information. && .AVIATION... (00Z TAFS) Issued at 631 PM CDT Thu May 21 2026 A broken line of storms is moving southeast across much of the area for the start of the period. TEMPO groups have included for I-35 terminals for the best timing as these thunderstorms pass. Another complex may form in the west, moving over the Rio Grande and potentially reaching KSAT/KSSF around 09Z. By Friday morning, drier conditions are expected which should last much of the day. MVFR ceilings are forecast to develop over the eastern Hill Country into the I-35 corridor early Friday morning returning to VFR conditions late morning. && .PRELIMINARY POINT TEMPS/POPS... Austin Camp Mabry 69 88 72 84 / 30 20 20 90 Austin Bergstrom Intl Airport 68 87 71 83 / 30 20 20 90 New Braunfels Muni Airport 67 86 70 83 / 30 20 20 90 Burnet Muni Airport 66 85 69 81 / 30 20 30 90 Del Rio Intl Airport 67 89 70 85 / 30 0 40 50 Georgetown Muni Airport 67 86 70 82 / 30 10 30 90 Hondo Muni Airport 66 85 69 81 / 30 10 50 90 San Marcos Muni Airport 68 87 71 83 / 30 20 20 90 La Grange - Fayette Regional 69 86 72 83 / 30 30 20 90 San Antonio Intl Airport 69 87 72 83 / 30 20 30 90 Stinson Muni Airport 69 87 72 83 / 30 20 30 90 && .EWX WATCHES/WARNINGS/ADVISORIES... Flood Watch from Friday evening through Monday evening for TXZ171>173-186>194-204>209-219>225. && SHORT TERM...CJM LONG TERM....CJM AVIATION...27
Special Weather Statement
National Weather Service Austin/San Antonio TX
410 PM CDT Thu May 21 2026
TXZ171-188-212200-
Gillespie TX-Llano TX-
410 PM CDT Thu May 21 2026
...A strong thunderstorm will impact portions of northwestern
Gillespie and southwestern Llano Counties through 500 PM CDT...
At 410 PM CDT, Doppler radar was tracking a strong thunderstorm 7
miles southwest of Hilda, or 14 miles south of Mason, moving east at
30 mph.
HAZARD...Winds in excess of 40 mph and penny size hail.
SOURCE...Radar indicated.
IMPACT...Gusty winds could knock down tree limbs and blow around
unsecured objects. Minor damage to outdoor objects is
possible.
Locations impacted include...
Castell, Cherry Spring, Prairie Mountain, Doss, Enchanted Rock State
Natural Area, and Harper.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
If outdoors, consider seeking shelter inside a building.
Torrential rainfall is also occurring with this storm and may lead to
localized flooding. Do not drive your vehicle through flooded
roadways.
Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.
&&
LAT...LON 3070 9872 3030 9893 3040 9930 3050 9931
3050 9896 3070 9896
TIME...MOT...LOC 2110Z 279DEG 24KT 3053 9922
MAX HAIL SIZE...0.75 IN
MAX WIND GUST...40 MPH
MMSpecial Weather Statement
National Weather Service Austin/San Antonio TX
505 PM CDT Thu May 21 2026
TXZ172-173-212245-
Williamson TX-Burnet TX-
505 PM CDT Thu May 21 2026
...A strong thunderstorm will impact portions of west central
Williamson and central Burnet Counties through 545 PM CDT...
At 504 PM CDT, Doppler radar was tracking a strong thunderstorm near
Longhorn Cavern State Park, or near Marble Falls, moving northeast at
25 mph.
HAZARD...Winds in excess of 40 mph and penny size hail.
SOURCE...Radar indicated.
IMPACT...Gusty winds could knock down tree limbs and blow around
unsecured objects. Minor damage to outdoor objects is
possible.
Locations impacted include...
Burnet, Marble Falls, Bertram, Granite Shoals, Meadowlakes, Lake
Victor, Sunnylane, Longhorn Cavern State Park, Joppa, Oatmeal, Shady
Grove, and Inks Lake State Park.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
If outdoors, consider seeking shelter inside a building.
Torrential rainfall is also occurring with this storm and may lead to
localized flooding. Do not drive your vehicle through flooded
roadways.
&&
LAT...LON 3073 9786 3053 9828 3067 9841 3101 9815
TIME...MOT...LOC 2204Z 234DEG 20KT 3065 9827
MAX HAIL SIZE...0.75 IN
MAX WIND GUST...40 MPH
CJMSpecial Weather Statement
National Weather Service Austin/San Antonio TX
525 PM CDT Thu May 21 2026
TXZ171-172-190-212315-
Blanco TX-Llano TX-Burnet TX-
525 PM CDT Thu May 21 2026
...A strong thunderstorm will impact portions of northwestern Blanco,
southeastern Llano and southwestern Burnet Counties through 615 PM
CDT...
At 525 PM CDT, Doppler radar was tracking a strong thunderstorm over
Sandy, or 9 miles west of Round Mountain, moving northeast at 20 mph.
HAZARD...Wind gusts up to 50 mph and penny size hail.
SOURCE...Radar indicated.
IMPACT...Gusty winds could knock down tree limbs and blow around
unsecured objects. Minor damage to outdoor objects is
possible.
Locations impacted include...
Marble Falls, Round Mountain, Granite Shoals, Horseshoe Bay,
Meadowlakes, Highland Haven, Spicewood, Blowout, Sandy, Cottonwood
Shores, and Sunrise Beach Village.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
If outdoors, consider seeking shelter inside a building.
Torrential rainfall is also occurring with this storm and may lead to
localized flooding. Do not drive your vehicle through flooded
roadways.
&&
LAT...LON 3046 9814 3027 9852 3035 9859 3047 9859
3068 9833
TIME...MOT...LOC 2225Z 232DEG 17KT 3039 9852
MAX HAIL SIZE...0.75 IN
MAX WIND GUST...50 MPH
CJMSpecial Weather Statement
National Weather Service Austin/San Antonio TX
619 PM CDT Thu May 21 2026
TXZ183>186-220015-
Kerr TX-Val Verde TX-Edwards TX-Real TX-
619 PM CDT Thu May 21 2026
...Strong thunderstorms will impact portions of northwestern Kerr,
northern Edwards, northeastern Val Verde and northwestern Real
Counties through 715 PM CDT...
At 618 PM CDT, Doppler radar was tracking strong thunderstorms along
a line extending from near Telegraph to 10 miles northeast of Juno.
Movement was southeast at 10 mph.
HAZARD...Wind gusts up to 50 mph and penny size hail.
SOURCE...Radar indicated.
IMPACT...Gusty winds could knock down tree limbs and blow around
unsecured objects. Minor damage to outdoor objects is
possible.
Locations impacted include...
Rocksprings, Kerr Wildlife Management Area, Devil's Sinkhole State
Natural Area, Vinegarone, and Devils River State Nat Area Del Norte.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
If outdoors, consider seeking shelter inside a building.
Torrential rainfall is also occurring with these storms and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.
Frequent cloud to ground lightning is occurring with these storms.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.
These storms may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.
&&
LAT...LON 3028 10109 3029 9973 3002 9945 2994 10091
TIME...MOT...LOC 2318Z 328DEG 10KT 3026 9996 3023 10097
MAX HAIL SIZE...0.75 IN
MAX WIND GUST...50 MPH
CJMThe Ft Hood radar (KGRK), 94 km away, was scanning. The volume nearest the first event began at 23:41 UTC.
1 flash flood. Local standard time, as filed.
Thunderstorms produced heavy rain that led to flash flooding. Flooding was reported throughout the city of Granite Shoals.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Texas in 2026Every state in 2026This day in weather historyWarnings in Texas, May 2026
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: 1340651.