textproduct: Austin/San Antonio

KEY MESSAGES

- Flood Watch remains in effect for the holiday weekend.

- Locally heavy rain in multiple rounds of storms through Monday. Localized flash flooding is likely.

- Active and unsettled weather pattern to continue into at least late Wednesday with addition localized flooding issues possible.

SHORT TERM

(Today through Sunday) Issued at 1242 AM CDT Sat May 23 2026

Broad upper troughing is keeping the pattern active in the short- term, and today's relatively more quiet day is not turning out quite as quiet as we'd hoped. A line of storms looked like it was on it's last legs but was able to rebound a bit while moving through Kerrville towards San Antonio. Motion is about 35 mph so the threat of run-off issues will be relatively low despite the Flood Watch in effect. Expected rainfall amounts should be mainly 1/4 to 1 inch with the higher amounts expected to go over along the Guadalupe basin where totals were relatively lighter over the past 2 days. Another, stronger, cluster of storms moving toward San Saba had recent severe storm warning issuances, and could provide a more significant localized flood threat as this cluster appears to be in line to impact recently flood stricken areas of NE Llano, northern Burnet and NW Williamson Counties. It also could produce similar type of rainfall amounts with is forward speed also around 35 mph. The southern line continuing to strengthen, could propagate northward enough to connect with the other cluster should both hold together long enough to reach the Austin area. With all that said will make some early short range changes and perhaps discount some the midday rainfall potential as this activity overall is trending toward a nocturnal-friendly environment. This means the high rain chances expected for Saturday into Saturday evening will be lowered to account for the late night preferences.

Messaging for our Situation Reports for today and tonight will be extra complicated as we aren't really able to get into expected QPF specifics outside of daily amounts and storm totals. While today and tonight trends will probably have to be dumbed down to a 50-50 shot, a larger disturbance arrives for daytime Sunday, making Sunday, the most likely period were a larger scale flood event could take place. We think our Sunday PoPs might be running a bit low given what the latest deterministic runs are showing, but at the same time we don't want to stray too far from the blends, as seemingly all models have been struggling with this pattern at one time or another. Messaging therefore continues as a daily risk of 1 to 2 isolated 3 and storm totals ending Sunday that could reach 6 inches. This means some of our totals if you go back to Tuesday's start, will be underestimated. For instance, a near 6 inch report was received on the first night at Florence, so they may end up with closer to 10 inches by Monday. However, going to those higher amounts would be confusing, and the isolated 6 inch messaging continues to cover the current time up through Monday.

LONG TERM

(Sunday night through Friday) Issued at 1242 AM CDT Sat May 23 2026

Sunday night will appear as if the storm activity will take a break as the mid to upper level low sits over East TX leaving far East TX and LA as the likely locations for widespread heavy rains. However, this time of year and the Pwat amounts likely to still be in the area could lead to unstable NW Flow aloft storms which might favor nocturnal traits similar to what we're getting right now. There is also some deterministic model tendencies of showing the upper low retrograding and wobbling back west at some point during this general Sunday night to Monday period, which would also send PoP trends back up. If benign weather settles by Sunday night, then Monday's pattern might suggest a continued respite through the afternoon while a weak shortwave mid to upper ridge works east across the area. We'll not know these trends until Sunday afternoon at the earliest, so there's no reason to pull back on the Watch and the messaging for Monday.

By Tuesday morning, the unstable SW flow pattern comes right back for another round of stormy weather that could continue through Wednesday night. Our highest PoPs of the week center on this period with the deterministic runs all in good agreement of peak activity around 12Z Wednesday. By daytime Thursday, the deterministic model runs also look to show some good agreement on a slightly better shortwave mid to upper level ridge over TX that could potentially get us a few stable weather days Thursday through Saturday.

AVIATION

(06Z TAFS) Issued at 1242 AM CDT Sat May 23 2026

A line of convection has moved east of SAT and SSF and continues to weaken while approaching AUS. We will not mention any TSRA for AUS this morning, with TSRA ending shortly for SAT and SSF. We are also monitoring convective trends well to the west of DRT. As of now, we will not mention TSRA yet as most models show the more organized activity farther south of DRT. Concerns will then turn to MVFR cig development overnight. We will continue to mention MVFR cigs, but have shortened the duration as high clouds will disrupt low-level cooling/saturation. Timing of the next round of showers and storms remains problematic. For now, will continue to mention PROB30 groups at all TAF sites and focus on the peak heating hours.

PRELIMINARY POINT TEMPS/POPS

Austin Camp Mabry 86 69 84 69 / 50 50 40 10 Austin Bergstrom Intl Airport 85 69 84 69 / 60 50 40 10 New Braunfels Muni Airport 85 67 84 67 / 50 60 50 10 Burnet Muni Airport 83 67 82 66 / 50 50 40 10 Del Rio Intl Airport 88 68 91 70 / 20 20 10 10 Georgetown Muni Airport 84 68 82 67 / 50 50 40 10 Hondo Muni Airport 83 66 85 67 / 50 60 40 30 San Marcos Muni Airport 85 68 84 68 / 60 60 50 10 La Grange - Fayette Regional 86 69 82 68 / 70 60 60 20 San Antonio Intl Airport 84 69 86 69 / 50 60 50 10 Stinson Muni Airport 84 68 85 69 / 50 60 50 10

EWX WATCHES/WARNINGS/ADVISORIES

Flood Watch through Monday evening for TXZ171>173-186>194- 204>209-219>225.