textproduct: Austin/San Antonio

KEY MESSAGES

- A powerful cold front arriving this afternoon/evening will bring strong winds, critical fire weather conditions, and much colder temperatures across South-Central Texas.

- Critical fire weather conditions linger into Monday as winds gradually weaken during the day.

- Light freezes are possible over the Hill Country Monday morning and over the Hill Country and adjacent low lying areas near the Balcones Escarpment Tuesday morning.

- A rain free forecast remains through next week with a warming trend from midweek through the weekend.

SHORT TERM

(Tonight through Monday night) Issued at 1245 PM CDT Sun Mar 15 2026

The strong cold front arriving later this afternoon is on its way, with the leading edge along the I-20 corridor as of noon. Before its arrival here, the combined warming effects of compressional heating and downsloping flows will impinge on the Balcones Escarpment, and we continue to project daily record warmth this afternoon along the I-35 corridor with highs in the mid 90s. To the west, relative humidity values below 20% are beginning to spread into the Hill Country behind an advancing dry line, delineating the spread of critical fire weather conditions. A Red Flag Warning is now in effect. The dry line should continue east of I-35 by the mid- afternoon.

By around 3-4 PM, the cold front should reach our northernmost counties in the Hill Country, racing south across the area and sweeping across our southernmost counties in the Rio Grande and Coastal Plains by about 8-9 PM. Strong north winds will develop quickly behind the front. Widespread sustained winds of 20-30 mph with gusts of 40-50 mph are expected across South-Central Texas. Most of the hi-res models also suggest enhancement of winds at higher terrain after sunset, especially after 9 PM along the southern rim of the Edwards Plateau. Sustained winds could reach 35 mph with gusts to 55 mph along these ridgetops. A Wind Advisory will go into effect from 3 PM today to 5 AM Monday when the strongest winds are anticipated. Secure loose outdoor objects before the front arrives. Those operating high-profile vehicles especially along west- east roadways like I-10 and US-90 should use extra caution this evening and tonight. The front is expected to remain dry across our region, but a narrow, fast-moving band of showers with perhaps a rumble of thunder or two may develop along the leading edge of the front on the eastern fringes of our region.

The air will rapidly cool behind the front as winds quickly whip in a much colder airmass, with temperatures dropping into the 30s and low 40s by sunrise Monday. This represents an impressive 50-55 degree drop in temperatures over a roughly 15-hour window. A light patchy freeze is possible in the Hill Country. While winds are expected to be weaker during the coldest period, they will still be quite breezy and drive wind chills into the 20s and low 30s especially over the Edwards Plateau and Hill Country.

Monday will stay unseasonably cool during the afternoon, with mid- to upper-level clouds also suppressing warming some. Highs are expected to rise only into the 50s and low to mid 60s. Lingering breezy north winds along with dry air, especially along the I-35 corridor and Coastal Plains, will result in a continued threat for critical fire weather conditions. Winds across South-Central Texas should settle to a light to near calm flow as surface high pressure settles over the region. This will support more favorable conditions for radiational cooling. Monday night into Tuesday morning is forecast to feature the coldest temperatures of this cold spell with lows in the 30s for most of South-Central Texas. Light freezes will be possible in rural low-lying locations across the Coastal Plains, I-35 corridor, and Hill Country. For these areas, the likelihood of a freeze is moderate (40-60%) based on the latest model blend.

LONG TERM

(Tuesday through next Sunday) Issued at 1245 PM CDT Sun Mar 15 2026

A steady warming trend is forecast beginning Tuesday and should continue on to next weekend. As the parent trough associated with the cool early-week air moves east, an upper-level ridge is forecast to intensify over Desert Southwest and inch into our area over the course of the week. Southerly winds return to South-Central Texas on Tuesday, raising daytime temperatures back to near-average levels. By Friday and Saturday, daytime highs could again approach daily record highs with temperatures in the 90s. This ridging aloft will keep rain chances out of the picture throughout the week into the weekend with abundant clear skies.

AVIATION

(00Z TAFS) Issued at 557 PM CDT Sun Mar 15 2026

VFR flight conditions continue but winds will be impactful into and through the overnight. North winds will sustain in the 20 to 30 kt range with gusts as high as 40 kt. These winds may bring haze with slight visibilities reductions at KAUS and KSAT during this evening. Wind speeds subside into and through Monday, but remain breezy for especially the first half of the day. However, winds will become light on Monday night. A few high clouds are possible tonight before high clouds thicken Monday afternoon into Monday evening. Clouds will then decrease beyond the evening hours.

FIRE WEATHER

Issued at 1245 PM CDT Sun Mar 15 2026

A Red Flag Warning is in effect for all of South-Central Texas. A dry line is advancing to the I-35 corridor this afternoon. A combination of 10-20 percent relative humidity, 10-20 mph westerly winds, and unusually warm temperatures in the 90s in the wake of the dry line will support the initial period of critical fire weather, especially over the Hill Country and southern Edwards Plateau. The dry line then becomes overtaken by a powerful cold front mid- afternoon to around sunset across the region. Very strong north winds will arrive immediately and in the wake of this front with sustained wind speeds climbing into the 20 to 35 mph range and gusts as high as 45 to 55 mph. Expect for these strong winds to persist through much of the overnight. Low RH values will spread across the remainder of the region. Despite rapidly falling temperatures behind the front, moisture recovery will be poor with the highest humidity only in the 30 to 35 percent range tonight.

Expect minimum humidity to fall back into the 10 to 20 percent range Monday afternoon. Winds will remain breezy through Monday afternoon, especially across the Coastal Plains, but not nearly as strong as the speeds overnight. The primary areas of concern for critical fire weather Monday afternoon includes are mainly along and east of I-35 into the Coastal Plains, though daytime temperatures will be much lower and in the 50s. Wind speeds weaken to light levels across all areas into Monday night. Dry conditions persist through midweek with enough wind at times for pockets of some elevated fire weather conditions across portions of the region. Overnight moisture recovery improves later in the week with the return and increase of southerly flow, but a warming trend and dry air will continue to support daytime RH values below 35 percent.

CLIMATE

Issued at 1235 AM CDT Sat Mar 14 2026

Record High Temperatures

Mar 15(Sun) Austin Bergstrom 87 (1977) Austin Camp Mabry 92 (2016) San Antonio Intl 91 (1908) Del Rio 98 (1908)

Record Low Temperatures Mar 16(Mon) March 17(Tue) Austin Bergstrom 32 (1962,1947) 30 (2005) Austin Camp Mabry 30 (1924) 30 (1913) San Antonio Intl 27 (1947) 32 (1947) Del Rio 28 (1913) 33 (1969)

PRELIMINARY POINT TEMPS/POPS

Austin Camp Mabry 40 56 36 67 / 0 0 0 0 Austin Bergstrom Intl Airport 41 56 34 67 / 0 0 0 0 New Braunfels Muni Airport 40 58 34 67 / 0 0 0 0 Burnet Muni Airport 37 53 34 66 / 0 0 0 0 Del Rio Intl Airport 45 62 41 71 / 0 0 0 0 Georgetown Muni Airport 39 55 34 66 / 0 0 0 0 Hondo Muni Airport 41 60 34 68 / 0 0 0 0 San Marcos Muni Airport 41 58 34 67 / 0 0 0 0 La Grange - Fayette Regional 41 56 34 67 / 10 0 0 0 San Antonio Intl Airport 42 59 37 67 / 0 0 0 0 Stinson Muni Airport 44 60 37 69 / 0 0 0 0

EWX WATCHES/WARNINGS/ADVISORIES

Red Flag Warning until 8 PM CDT Monday for TXZ171>173-183>194- 202>209-217>225-228.

Wind Advisory until 5 AM CDT Monday for TXZ171>173-183>194- 202>209-217>225-228.