An upper level low moved out of Mexico and pushed a cold front through Texas. This generated thunderstorms that became severe.
Every event with a place to put it. Tap one for its entry below.
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 low moved out of Mexico and pushed a cold front through Texas. This generated thunderstorms that became severe.
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 Apr 1, 9:40 PM CST, 19 minutes earlier.
Area Forecast Discussion...UPDATED National Weather Service Austin/San Antonio TX 1040 PM CDT Sat Apr 1 2017 .UPDATE... Tornado Watch has been issued for portions of the southern Edwards Plateau and Rio Grande through 6 AM. && .PREV DISCUSSION... /ISSUED 911 PM CDT Sat Apr 1 2017/ UPDATE... A vorticity maximum is noted on water vapor rotating through the base of the upper level low across northwest Mexico this evening. Flow through the lowest 4k feet off DFX radar has backed east-southeast and increased to 20-30 kts. This will continue to increase through the late evening and as deeper large scale forcing approaches should see a quick expansion in coverage of storms across Val Verde County 03Z-06Z. Already some indications of this starting just across the border. The storms should expand further in coverage across the southern Edwards Plateau and Rio Grande 06Z-09Z. Initially discrete storms could yield a large hail risk however as a northeast to southwest oriented cold front enters the area from the north could see storms training parallel to the front. After coordination with WPC feel there is enough threat to warrant locally heavy rainfall mention late this evening and into portions of the overnight across the far western CWA. No changes this evening to the forecast thinking for Sunday morning farther east across the Hill Country and eventually along and east of I-35. This area will remain in a favorable location for some storms to produce large hail and damaging straight-line winds. An isolated tornado threat will also exist. PREV DISCUSSION... /ISSUED 658 PM CDT Sat Apr 1 2017/ AVIATION... All airports are VFR except for SSF which MVFR. This may only be temporary and they may be up and down for the next few hours. MVFR CIGs will settle over the Austin and San Antonio areas by around 03Z. Showers will develop around 06Z in the Austin and San Antonio areas. Thunderstorms will develop out west and DRT will see TSRA by around 07Z. Thunderstorms will move into Austin and San Antonio Sunday morning. Scattered storms will last into the afternoon. When the storms clear CIGs will improve to VFR and winds will shift to the southwest to west. PREV DISCUSSION... /ISSUED 419 PM CDT Sat Apr 1 2017/ SHORT TERM (Tonight through Sunday Night)... Low clouds are beginning to lift southwest of a Fredericksburg to New Braunfels to Cuero line to allow temperatures to generally warm up into the 80s with lower 90s later this afternoon in the Rio Grande Plains. Significant dry slotting from the southwest evident on water vapor imagery is contributing to this and will likely allow clouds to break up a bit more over the rest of the area later this afternoon except for possibly northern portions of the Hill Country. Shallow convective showers are forming along the Escarpment between San Antonio and Austin between areas with relatively clear skies to the west and overcast skies to the east, and these should continue over through the early evening hours. A few hi-res models show a stronger cell or two, but model soundings continue to predict an inversion at 700 mb that is quite a bit weaker than that observed on aircraft soundings at AUS and SAT. Although dry air aloft will steepen lapse rates, slightly drier air moving into the midlevels will make it that much harder to overcome the cap at 700 mb. Thus, deeper convection this afternoon is unlikely given the lack of a clear surface trigger or shortwave aloft, but any cell that makes it past the cap will have sufficient shear and instability to support severe storms. Strong to severe thunderstorms are expected to develop just over the border in Mexico west of Del Rio around Midnight as a lead shortwave rotates ahead of the broader positively-tilted trough west of Big Bend and the synoptic cold front moves into the region. The initial storm mode should be supercellular given shear values in excess of 40-50 knots, so the damaging winds and hail will be the main threats overnight, but a tornado cannot be ruled out with SRH values around 100 m^2/s^2 that could be locally enhanced depending on how the storm interacts with the environment. A steady feed of low-level moisture supplied by a 20-30 knot southeasterly LLJ will support low LCLs that could also increase this threat. This LLJ will also help provide a brief window for locally heavy rainfall after Midnight in the Edwards Plateau and Rio Grande Plains until the cold front approaches and the system begins to become cold pool dominated by 7 am. A few instances of flash flooding may be possible due to terrain and rainfall totals up to 3 inches in isolated areas, but not widespread enough or long enough to issue a watch at the current moment. These cells should transition to a more linear system moving from west to east along the front by sunrise. Ahead of this line, scattered showers should be ongoing across the rest of the region beneath a weak cap with isentropic ascent and an increasing LLJ out of the S-SE. Deeper cells should begin to develop by sunrise as the cap erodes much earlier than normal near the I-35 corridor north of San Antonio as the larger-scale forcing and height falls associated with an upper level trough ejecting out of Mexico approaches the Rio Grande Plains. This trough will be transitioning from a positive to more negative tilt that will increase diffluence aloft for areas mainly along and east of I-35 for the morning and afternoon hours on Sunday. Shear values in excess of 50 knots with abundant CAPE increasing from ~1500 J/kg towards possibly 4000 J/kg by Noon with steepening lapse rates aloft will support strong supercells capable of producing large hail and damaging winds. Very low LCLs and SRH values increasing towards 250-300 m^2/s^2 provide strong support for tornadic supercells (possibly strong tornadoes) tomorrow morning into the afternoon hours for our eastern counties. If the line merges with these cells, we could see some instances of QLCS mergers, but some hi-res models are trending towards weakening this line with fewer, but more significant supercells most likely caused by significant dry air moving in at midlevels. It is hard to tell which scenario will play out at this point, but the general threats would remain the same and most models show that the tornado and significant severe threat should end by early or mid-afternoon for the I-35 corridor and by 6 pm for our eastern counties. Given the significant nature of the severe weather threat expected for tomorrow, potential for dry slotting, and a marginal threat of locally heavy rainfall for our northern counties, we have elected to not issue any watch for flash flooding for now. Global and hi-res models continue to indicate that some additional showers and thunderstorms will develop as the upper low passes over the region or just to our north tomorrow evening. The main threat with these storms would be small or large hail, but not tornadoes or locally heavy rainfall. Skies should begin to clear behind this system to set up a nice Monday. LONG TERM (Monday through Saturday)... Next week should be dry and very nice behind this strong system with southwest flow continuing aloft for Monday and Tuesday and highs in the 80s and potentially lower 90s in the Rio Grande Plains. This dry air mass will cause elevated fire weather concerns for spots over the Rio Grande Plains that do not receive wetting rains in the next 24 hours, but this should just be our southwestern most counties. A weak front will move through Tuesday evening into Wednesday to further dry and cool the area out back closer to normal temperatures before a gradual warmup begins later next week. && .PRELIMINARY POINT TEMPS/POPS... Austin Camp Mabry 68 78 57 84 60 / 50 80 30 0 0 Austin Bergstrom Intl Airport 68 78 56 84 57 / 50 80 30 0 0 New Braunfels Muni Airport 68 78 55 84 57 / 50 80 30 0 0 Burnet Muni Airport 64 72 53 81 56 / 50 80 30 0 0 Del Rio Intl Airport 66 73 54 87 58 / 80 60 - 0 0 Georgetown Muni Airport 66 75 56 82 57 / 50 80 40 0 0 Hondo Muni Airport 68 81 53 85 56 / 50 70 20 0 0 San Marcos Muni Airport 68 79 55 84 57 / 50 80 30 0 0 La Grange - Fayette Regional 70 80 57 82 59 / 40 80 30 0 0 San Antonio Intl Airport 68 80 56 85 59 / 50 80 20 0 0 Stinson Muni Airport 69 81 55 85 58 / 50 70 20 0 0 && .EWX WATCHES/WARNINGS/ADVISORIES... None. && Mesoscale/Aviation...05 Synoptic/Grids...Runyen Public Service/Data Collection...Treadway
Hazardous Weather Outlook National Weather Service Austin/San Antonio TX 606 AM CDT Sat Apr 1 2017 TXZ171>173-183>194-202>209-217>225-228-021115- 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- 606 AM CDT Sat Apr 1 2017 This Hazardous Weather Outlook is for South-Central Texas.. .DAY ONE...Today And Tonight. Shower and thunderstorm activity will be on the increase this afternoon. There is a low chance of a strong storm or two this afternoon for areas west of an Eagle Pass to Burnet line. The chance for severe weather, including large hail, damaging winds and an isolated tornado will begin to take shape late this evening across the Rio Grande plains and southern Edwards plateau. .DAYS TWO THROUGH SEVEN...Sunday through Friday. An active weather pattern is expected across all of south central Texas on Sunday. Initially, the most active weather will be across the southern Edwards Plateau as a line of storms begins to organize. As this line of storms strengthens and moves east across the Hill Country and I-35 corridor through midday, a combination of large hail, damaging winds and locally heavy rainfall can be expected. In addition, an isolated tornado can not be ruled out. As this line of storms approaches the I-35 corridor Sunday morning, the threat for tornadoes will increase. In addition, rainfall amounts of 1 to 3 inches could bring the potential for localized flooding, especially across those areas that had heavy rains earlier in the week. By early Sunday evening, the severe weather concerns should be on the decrease as the line of storms moves east of the region. .SPOTTER INFORMATION STATEMENT... Spotters are urged to report severe weather and flooding with the storm system this weekend.
Special Weather Statement
National Weather Service Austin/San Antonio TX
735 PM CDT SAT APR 1 2017
TXZ183-020115-
Val Verde TX-
735 PM CDT SAT APR 1 2017
...SIGNIFICANT WEATHER ADVISORY FOR NORTHWESTERN VAL VERDE COUNTY
UNTIL 815 PM CDT...
At 734 PM CDT, Doppler radar was tracking a strong thunderstorm near
Langtry, moving northeast at 50 mph. This storm is still in Mexico,
but will cross the river within the next few minutes.
Nickel size hail and wind gusts up to 50 mph will be possible with
this storm.
Locations impacted include...
Langtry, Juno, and Shumla.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
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 3028 10144 3018 10107 2971 10140 2973 10139
2975 10142 2977 10140 2975 10144 2979 10146
2976 10151 2976 10154 2980 10154 2981 10155
2980 10157 2977 10158 2977 10161
TIME...MOT...LOC 0034Z 205DEG 43KT 2977 10150Special Weather Statement
National Weather Service Austin/San Antonio TX
738 PM CDT SAT APR 1 2017
TXZ183-020115-
Val Verde TX-
738 PM CDT SAT APR 1 2017
...SIGNIFICANT WEATHER ADVISORY FOR NORTHEASTERN VAL VERDE COUNTY
UNTIL 815 PM CDT...
At 736 PM CDT, Doppler radar was tracking a strong thunderstorm 7
miles northwest of Box Canyon-Amistad, or 8 miles southwest of
Comstock, moving northeast at 60 mph. This storm is still in Mexico,
but will cross the river within the next few minutes.
Nickel size hail and wind gusts up to 50 mph will be possible with
this storm.
Locations impacted include...
Comstock, Box Canyon-Amistad, Bakers Crossing, and Devils River
State Natural Area.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
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 3016 10105 3005 10075 2951 10117 2952 10120
2952 10125 2954 10126 2957 10124 2962 10125
2963 10127 2958 10128 2958 10131 2961 10131
2965 10130 2966 10133
TIME...MOT...LOC 0036Z 208DEG 51KT 2958 10126The Laughlin AFB radar (KDFX), 92 km away, was scanning. The volume nearest the first event began at 04:00 UTC.
24 thunderstorm wind, 18 hail, 6 flash flood, 1 tornado. Local standard time, as filed.
A thunderstorm produced golf ball size hail near Comstock. The report was forwarded to us by Laughlin AFB weather from the Border Patrol.
A thunderstorm produced quarter size hail at Seminole Canyon State Park.
A thunderstorm produced ping pong ball size hail at Seminole Canyon State Park.
A thunderstorm produced quarter size hail in the Buena Vista Park part of Del Rio. The report was forwarded to us by Laughlin AFB weather from the Del Rio Emergency Manager.
Thunderstorms produced heavy rain that led to flash flooding of the intersection of Main and Gibbs Sts. in Del Rio.
A thunderstorm produced quarter size hail at Laughlin AFB.
Thunderstorms produced heavy rain that led to flash flooding. Multiple water rescues and vehicles stuck in water were reported around Del Rio.
A thunderstorm produced wind gusts estimated at 80 mph that destroyed a carport and ripped metal roofs off two houses south of Leakey.
A thunderstorm produced wind gusts estimated at 90 mph that destroyed a large metal building in Boerne.
Thunderstorms produced heavy rain that led to flash flooding closing FM674 along the West Nueces River southwest of Rocksprings.
A thunderstorm produced wind gusts estimated at 75 mph that blew down trees in Ingram.
A thunderstorm produced wind gusts estimated at 75 mph that blew down large Pecan trees south of Leakey.
A thunderstorm produced wind gusts estimated at 75 mph that snapped and uprooted trees in Camp Verde.
A thunderstorm produced wind gusts estimated at 75 mph that blew down a tree in Boerne.
A thunderstorm produced wind gusts estimated at 75 mph that blew down trees near Hwy 281 and FM 473 in southern Blanco County.
Thunderstorms produced heavy rain that led to flash flooding closing FM336 from Hwy 83 to Hwy 41 along the West Frio River.
A thunderstorm produced wind gusts estimated at 60 mph that damaged trees northeast of Spring Branch.
A small tornado developed on the leading edge of squall line moving over the Lake Travis area. Many trees were blown down and damaged. A security cam video shows a developing circulation near Noack Hill at a residence. Tree damage can be seen along R O Drive toward Bee Creek. A couple of videos from citizens show a waterspout crossing Lake Travis near Bee Creek, moving east toward Point Venture. Several marinas were damaged as the small tornado crossed the lake. It is assumed the tornado came ashore near the park area of Point Venture on Whispering Hollow Drive where there is tree damage. At this point, concrete evidence of a tornado and tornado damage is lost so the path of the EF0 tornado is ended on the far west side of Point Venture. Estimated peak winds are 80 mph with a maximum width of 100 yards. The path length is estimated to be at 3 miles. Other house and roof damage was found on the south side of Point Venture but there was not enough evidence to call it tornado damage.
A thunderstorm produced wind gusts estimated at 60 mph that damaged trees and a building near Lakeway.
A thunderstorm produced wind gusts estimated at 60 mph that blew down tree limbs in Lakeway.
A thunderstorm produced wind gusts estimated at 75 to 80 mph that downed large trees on Point Venture near Lake Travis. In addition, several homes sustained wind damage especially those that were on the south side of the point facing Lakeway. Roofs and patios had the most damage as radar indicated winds in excess of 70 kt blowing through the area. With multiple homes damage including resulting water damage, estimates of monetary loss may be as high as one million dollars.
Several houses on or near Costa Bella Drive sustained roof and chimney damage. Some chimneys were broken off. Several marinas and even a floating restaurant were damaged on the lake shore from thunderstorm winds that are estimated to be as high as 80 mph. Many homes sustained damage in and around the Lakeway area. Estimates of damage are incomplete but may be as high as one million dollars, possibly higher based on the large and expensive homes in that area and neighborhood.
A thunderstorm produced wind gusts estimated at 80 mph that snapped a power pole in half near Hudson Bend Middle School.
A thunderstorm produced wind gusts estimated at 60 mph that knocked down tree limbs at the Sundancer Grill restaurant in Lakeway.
A thunderstorm produced wind gusts estimated at 70 mph.
Thunderstorms produced heavy rain that led to flash flooding closing RM3008 along Perdido Creek northeast of Amanda.
Thunderstorms produced heavy rain that led to flash flooding closing RM2804 northwest of Brackettville.
A thunderstorm produced wind gusts estimated at 60 mph that knocked down tree limbs near Cedar Park.
A thunderstorm produced wind gusts estimated at 60 mph.
A thunderstorm produced wind gusts estimated at 60 mph that knocked a five inch tree limb down a parked car near the intersection of Sans Souci Cove and Sans Souci Pl. in the Great Hills area of northwestern Austin.
A thunderstorm produced wind gusts estimated at 60 mph near Parmer Ln at RR620 in Jollyville.
A thunderstorm produced wind gusts estimated at 60 mph that blew down tree limbs in Leander.
A thunderstorm produced wind gusts estimated at 60 mph that snapped large tree limbs along Hairy Man Rd. in Round Rock.
A thunderstorm produced wind gusts estimated at 60 mph that blew down small tree limbs near Sun City.
A thunderstorm produced quarter size hail in Georgetown.
A thunderstorm produced wind gusts estimated at 80 mph that blew down large tree limbs southwest of Weir.
A thunderstorm produced wind gusts estimated at 60 mph in Georgetown.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Texas in 2017Every state in 2017This day in weather historyThe tornado archive for Texas, 2017Warnings in Texas, April 2017
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: 685488, 685489, 685490, 685491, 685518, 685492, 685519, 685493, 685494, 685545, 685495, 685496, 685547, 685524, 685548, 685497, 685549, 685553, 685555, 685498, 685557, 685528, 685558, 693573, 685562, 685559, 686298, 693568, 686296, 686299, 685500, 685502, 685533, 685537, 686300, 685503, 685504, 686302, 685505, 685506, and more.