textproduct: Houston/Galveston

KEY MESSAGES

- Scattered showers and storms are expected this afternoon and evening with a threat for strong winds and locally heavy rainfall.

- Hot and humid conditions with low chances for showers/storms will continue into next week.

DISCUSSION

SHORT TERM

(This afternoon through Friday Night) Issued at 1208 PM CDT Thu Aug 27 2026

Water vapor imagery shows an upper disturbance spreading out of western Oklahoma into North Texas at this time with convection developing along an outflow boundary well to our north. At the surface, a quasi stationary frontal boundary draped south of the I-20 corridor will begin to sag south as a weak cold front through this afternoon. While we're not expecting any significantly cooler weather, a broad area of low level convergence will develop across southeast TX through the afternoon aided by weak forcing for ascent from the upper disturbance. This will occur during peak afternoon heating and we should see a notable uptick in convective activity across the region this afternoon and evening. While showers and thunderstorms will still remain scattered, coverage should increase to 40-60% later today.

Low and mid level flow is generally weak with 0-6km shear <15kt as indicated by the last hour of data from the HGX VAD wind profile, however mid and upper flow is forecast to strengthen a bit through the afternoon which may allow for convective updrafts to become a little more organized. Given MLCAPE increasing to 2500J/kg through peak heating and mean storm motions around 15 kt, we may see a slightly higher threat for strong winds with any storms that develop this afternoon than we would typically see in a summertime pulse type environment. GOES derived PW values between 2.1-2.3 inches across the region will support a locally heavy rainfall potential, although storm motions may keep this threat limited in area through the evening.

Convection should wind down through the late evening with loss of heating although we'll maintain some low PoPs through the overnight hours given the proximity of the weak boundary in the area. This boundary will continue to push southward into Friday with the bulk of any convection likely being offshore through the rest of the period. Temperatures will be a touch cooler today given the extra cloud cover and convective potential and should remain in the mid/upper 90s for Friday afternoon.

Dunn

LONG TERM

(Saturday through next Wednesday) Issued at 1208 PM CDT Thu Aug 27 2026

The mid level ridge axis will still be centered across far West Texas on Saturday but will begin to expand eastward across the Southern Plains into early next week. Meanwhile, a disturbance over the northern Gulf will move westward, undercutting the ridge a bit and spreading into Texas by Tuesday. Unfortunately it appears that the better moisture associated with this disturbance will remain primarily to the east, but weak ascent should aid an increasingly active sea breeze boundary Monday through Wednesday. Afternoon temperatures will remain fairly steady with highs in the mid to upper 90s and peak heat indices between 105-110 degrees.

Dunn

AVIATION

(00Z TAF Issuance) Issued at 722 PM CDT Thu Aug 27 2026

Sct convection continues to develop around HOU n'wrd and is proceeding southward before weakening this evening. This round of convection has verification to produce VRB winds gusts up to 25kts and is anticipated to last until around 2-3z this evening. CXO/UTS/CLL do have the chance for BR or MVFR CIGS in the morning hrs around 12-14z. Winds become light and VRB overnight. During the post frontal passage, winds shift to NE before veering back to ESE in the afternoon. The frontal boundary is expected to stall out and have the possibility to produce another round of convection tomorrow afternoon mainly south of I-10. Confidence in occurrence is currently low on in-land terminals thus PROB30 have been omitted from TAFs. We will continue to monitor on following TAF period.

CMW

MARINE

Issued at 1208 PM CDT Thu Aug 27 2026

Morning convection has largely diminished across the coastal water at this time with south-southwest flow 5-10 kt expected through the afternoon. A weak frontal boundary will slide southward later today with northerly flow 5-10 kt expected tonight into Friday. Scattered showers and thunderstorms will increase in coverage late this afternoon through late evening with gusty winds and locally higher seas expected. Onshore flow will resume late Friday and continue into the weekend with seas generally 1-2 feet.

Dunn

PRELIMINARY POINT TEMPS/POPS

College Station (CLL) 76 99 76 97 / 20 0 0 10 Houston (IAH) 79 97 79 97 / 50 10 0 10 Galveston (GLS) 82 89 82 90 / 40 30 10 10

HGX WATCHES/WARNINGS/ADVISORIES

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