textproduct: Houston/Galveston

KEY MESSAGES

- Mother's Day Sunday will remain mostly dry before the early afternoon as another round of severe thunderstorms is expected to emerge southward from Central Texas through the evening and overnight.

- Some isolated severe thunderstorms could form ahead of the main line of thunderstorms, and both rounds of storms will carry the threat of damaging winds and large hail.

- Dry and seasonable conditions are expected through the following workweek with a gradual warm-up by the end of the week.

DISCUSSION

Issued at 1221 AM CDT Sun May 10 2026

Weather conditions in the next 24-48 hours will be the most active in the forecast period across southeast Texas. This is due to a swiftly-moving embedded trough that is finishing emergence from the Intermountain West into the Southern Great Plains this morning. Attendant to this troughing is the frontal boundary driving our next chance of severe weather arriving later today. The favorable atmospheric environment ahead of this boundary consists/will consist of elevated mid-level lapse rates of 7-7.5 C/km and CAPE values in excess of 2500+ J/kg, while bulk shear of 30+ kts will also aid updraft separation for large hail production (especially with any isolated supercells that could form in the evening). The main line of strong to severe thunderstorms will begin to arrive closer to the evening twilight hours across Piney Woods zones, reaching the I-10 corridor before midnight. Damaging winds will become a more predominant threat overnight as the line of storms congeals and reaches the Upper Texas shoreline.

By the dawn hours of Monday morning, the storms and frontal boundary will be offshore with ensuing post-frontal conditions elsewhere, including some fairly seasonable temperature maximums/minimums in the low-to-mid 80s/upper 60s respectively. Surface northerly winds will continue later into Tuesday before veering back as the surface ridge axis shifts to our east towards the lower Mississippi River Valley. By the end of the next workweek, the 70-degree isodrosotherm makes its return with long- range guidance very gradually re-introducing some rain chances into next weekend. By then, some temperature maximums could reach the 90-degree mark.

Cassel

AVIATION

(18Z TAF Issuance) Issued at 1235 PM CDT Sun May 10 2026

Southeasterly 10-15 kt winds and VFR conditions expected this afternoon. Iso to sct SHRA/TSRA expected in the late afternoon and early evening north of I-10. Will need to monitor closely for possible amendments for possible afternoon activity. Overnight, the primary concern is a line of SHRA/TSRA that is expected to reach our northern terminals during the 03-06Z time frame. There is uncertainty regarding how far south the line will make it. At this time, we think it will make it to the coast by 09-11Z, though we are unsure how strong it will be. Some of the hi-res guidance is quite aggressive, bringing strong to severe storms all the way to the coast. Other guidance shows substantial weakening of the line. Hail and high winds are the primary concerns with thunderstorms, both from the iso/sct activity this afternoon and the line overnight.

MARINE

Issued at 1221 AM CDT Sun May 10 2026

The next 24-48 hours will be the most eventful across marine zones due to frontal passage beginning just before midnight on Sunday. A line of strong thunderstorms (some still severe) will emerge offshore, producing some moderate downdraft winds. After the storms abate in the dawning hours on Monday, post-frontal northerly winds will remain through the rest of the day before veering back onshore by Wednesday through the rest of the drier and milder workweek ahead. All post-frontal winds are expected to remain below the threshold requiring issuance of a Small Craft Advisory at this time.

Cassel

PRELIMINARY POINT TEMPS/POPS

College Station (CLL) 67 79 64 82 / 80 10 0 0 Houston (IAH) 70 83 68 85 / 70 20 10 0 Galveston (GLS) 75 83 72 81 / 40 20 10 0

HGX WATCHES/WARNINGS/ADVISORIES

TX...None. GM...None.