textproduct: Austin/San Antonio

KEY MESSAGES

- Rain chances across portions of the area later tonight through the overnight hours and into early Sunday, with locally heavy rainfall possible. - The heat and humidity continue this weekend into early next week, with perhaps a brief break on Saturday.

UPDATE

Issued at 458 PM CDT Fri Jun 19 2026

Cancelled the Heat Advisory early as an outflow boundary moved across the region and has brought relief from the hazardous heat. The outflow boundary is soon to exit our coastal plain counties to the south and east but continues to generate convection along and just in wake of that boundary from Karnes through Lavaca counties.

Otherwise, have made changes to the grids this evening and through the overnight. Temperatures and dew points have been adjusted to the conditions seen behind the outflow boundary. Have also lowered the PoPs drastically through the evening but do have the return for higher PoPs towards midnight and through the overnight, especially from the Rio Grande Plains/Highway 90 corridor through Bexar Country and southern Hill Country based on latest short term guidance but the overall pattern is of low confidence and chaotic pending complex propagation. A threat for locally heavy rainfall with heavier rainfall rates and isolated flooding remains with this increase in activity later tonight through the overnight hours.

SHORT TERM

(Tonight through Saturday night) Issued at 139 PM CDT Fri Jun 19 2026

A weak frontal boundary is continuing to move through the area. Several mcs have formed off of this boundary to our north and have kept thick cloud cover deck over our area along with some convection out across the far northern Hill Country and also across the Rio Grande. Ahead of this boundary the low level flow is from the southeast across our CWA. This is keeping a warm, moist airmass over South-Central Texas. Temperatures are still in the mid 80s with low 90s across the Coastal Plains and dewpoints are in the mid 70s to around 80 for most areas. Areas that saw convection have cooled considerably, along with those remaining under the cloud cover so we have decided to trim back our heat advisory. Lowered daily highs several degrees as there just isn't enough time and most Hi-Res model guidance keeps the cloud cover around. For most the Heat Advisory has been canceled with only parts of the Rio Grande and all of the Coastal Plains areas remaining.

Recent short term guidance suggests that convection continues to move across our northernmost counties with more popping out ahead of it. We are currently seeing this start to happen with scattered showers and thunderstorms popping up along and east of I-35. Guidance suggests another round forming late this evening and continuing into the overnight hours though due to increased cloud cover and the outflow boundaries working there way through the area however confidence is low on this scenario playing out.

PWATS are currently sitting at 1.8 to 2 inches regionwide so any storms that do form will be capable of producing torrential rainfall. As such WPC keeps our entire region in a level 2 of 4 risk for excessive rainfall for today. With the ground previously saturated even 1 to 2 inches in a short time would likely all be runoff and could lead to flooding concerns. For Saturday There may be an uptick in convection with daytime heating by Saturday afternoon. PWATS will remain high enough that locally heavy rain will be possible once again. Saturday night there will be some low chances for convection across the south as the last bit of energy moves away from our area.

Regarding Temperatures most should remain in the upper 80s to low 90s for highs for Saturday with heat indices once again in the 100- 107 degree range, highest out across the Coastal Plains. However it looks like we should stay just below advisory criteria. Lows tonight and Saturday night will remain very mild with upper 70s to near 80 possible.

LONG TERM

(Sunday through next Friday) Issued at 139 PM CDT Fri Jun 19 2026

For the long term the subtropical ridge will finally build back over TX Sunday into Monday bringing back dry weather. A persistent south to southeasterly flow will continue to help keep temperatures holding above average and remaining very warm. With humidity added in, the heat indices will be elevated again Sunday and Monday. It's possible that we may need a Heat Advisory for the I-35 Corridor and the Coastal Plains for this timeframe. We should stay just below heat advisory criteria for the rest of the forecast with highs in the mid to upper 90s and heat indices in the 100-107 degree range for most. Overnight lows will continue to be very warm and humid in the mid to upper 70s along with the returning low stratus most nights forming late each overnight and dissipating by mid morning. Drier weather is also expected through the rest of the forecast period giving most of us a much needed chance to dry out.

AVIATION

(00Z TAFS) Issued at 646 PM CDT Fri Jun 19 2026

All area airports are enjoying VFR conditions and the forecast calls for those conditions to remain across the I-35 terminals through at least midnight tonight.Then, MVFR cigs develop overnight and stay through mid Saturday morning. There may be some showers and storms overnight across South Central Texas but difficult to pinpoint as of now since hires models are having a hard time resolving tonight's weather. Confidence is a bit better for KDRT as storms are ongoing over northeast Mexico and looking to be moving to the east and getting closer to the Rio Grande Plains/Mexico border. A southeast flow is forecast to dominate the local area through this aviation forecast cycle with speeds of 5 to 10 knots and occasional higher gusts especially during storm activity. VFR conditions return mid to late Saturday morning and continue through the evening for all area sites.

PRELIMINARY POINT TEMPS/POPS

Austin Camp Mabry 76 91 78 95 / 20 30 10 0 Austin Bergstrom Intl Airport 76 91 78 95 / 30 30 10 0 New Braunfels Muni Airport 76 91 76 94 / 40 30 30 10 Burnet Muni Airport 73 89 76 94 / 20 30 10 0 Del Rio Intl Airport 74 93 77 98 / 20 10 10 0 Georgetown Muni Airport 75 90 77 95 / 20 30 10 0 Hondo Muni Airport 75 90 76 93 / 60 30 40 10 San Marcos Muni Airport 76 91 77 95 / 30 30 20 0 La Grange - Fayette Regional 78 91 78 93 / 30 30 10 10 San Antonio Intl Airport 76 90 78 93 / 60 30 30 10 Stinson Muni Airport 77 90 77 93 / 60 30 30 10

EWX WATCHES/WARNINGS/ADVISORIES

None.