textproduct: Houston/Galveston

KEY MESSAGES

- NHC continues to monitor an area of low pressure drifting WNW off the coast of SE LA.

- A Hurricane Hunter aircraft is scheduled to investigate this morning. Tropical Storm Watches or Warnings could be issued for parts of the Upper Texas coast today

- Increased rain chances Tuesday, some could be locally heavy.

- Daily chances for scattered showers/storms continues beyond midweek.

DISCUSSION and TROPICAL

Issued at 141 AM CDT Mon Aug 31 2026

A small but persistent area of convection persists off the coast of southeast LA this morning in association with AL97. An ASCAT pass earlier this evening shows a defined circulation, but with winds generally in the 15-30kt range. A Hurricane Hunter is scheduled to take a look at things this morning. Guidance generally takes this area of disturbed wx west-northwest today and tonight. On this track, it should be somewhere in the vicinity of SE TX or SW LA Tuesday. Most 0z guidance shows some good clustering around the Sabine Pass area, Intensity-wise generally in the 25-45kt range, but noted that 18z Google Deepmind mean was a bit closer to 50kt. This system is small, and until we get some plane data sampling its peripheral environment...there remains some uncertainty how everything will unfold. Watches/Warnings may be required for portions of the Upper Texas coast today.

Keeping in mind the aforementioned uncertainties, here's our preliminary thinking which will likely be refined later this morning:

Today: continued hot with a speckling of isolated daytime shower/storms. Most of us won't see much.

Tonight: a slight increase in wind speeds and rain chances (generally east and southeast of the Galveston area).

Tuesday: the system begins making its way to the coast. Should it go into locations to our east...then locations further to the west will likely see rain chances/impacts be tapered down from what'll be in tonight's forecast package. Hopefully the morning recon will refine things...

- Rainfall: Some 1-3" totals on average generally E/SE of a line from Huntsville to Galveston. Reasonable worst case scenario (based off 90th percentile and tropical rainfall climatology) up to 5-7". There remains a Slight Risk of Excessive rainfall in the SE quadrant of the CWA. Localized street flooding will be monitored for those 2-4"/hr rain rates.

- Winds: with considerable uncertainty...maybe some gusts to TS strength in our eastern coastal waters and Chambers County.

- Surge: not much of a concern in terms of coastal flooding. Maybe some elevated wave runup near and to the right of where the center goes in.

- Rivers/hydro: No widespread concerns. Exceptions would be on a localized level where rises would occur where any of the highest amounts of rain falls in a short time period.

- Marine & Aviation: see below

The deepest PW air moves north Tuesday night. Rain coverage should diminish but not be eliminated. With fairly stagnant heights around 591dm for much of the week, a continued onshore wind, and intermittent fluxes of higher PW air, I'd generally look for temps near or just above seasonable norms along with diurnally driven scattered showers and tstms on a daily basis. 47

AVIATION

(12Z TAF Issuance) Issued at 519 AM CDT Mon Aug 31 2026

For today, expect prevailing SE winds to develop by afternoon. One wild card in the forecast is the very high moisture levels pushing in from the east and the Gulf. Models are not showing much coverage today. However, we cannot rule out widely scattered shra/tsra given the moisture. For now, we have only added VCSH near the coast.

A system in the Gulf may become a tropical storm today, and influence our weather by tonight. Towards the end of the TAF period, we are expecting winds to increase somewhat from the N to NE along with an increasing chance of rain. Depending on the exact track of the system, we cannot rule out gustier winds and heavier shra/tsra tomorrow. Higher chance of sub-VFR conditions tomorrow as well.

MARINE

Issued at 141 AM CDT Mon Aug 31 2026

The National Hurricane Center is monitoring an area of low pressure and disturbed weather off the coast of southeast Louisiana. A short-lived tropical depression or tropical storm is likely to form before the system reaches the Upper Texas or southwestern Louisiana coasts on Tuesday. Tropical Storm Watches or Warnings may be required for portions of the upper Texas coast today. Mariners are advised to monitor the forecast for changes and updates.

As described above in the main discussion text, considering the small size of this system, I suspect eastern parts of the marine area will be much more prone to impacts in terms of navigation. Galveston Bay and adjacent waters will see an increase in precip coverage late Monday night and Tuesday. Some cells could be on the strong side with gusts to or above 35kt. The threat of waterspouts cannot be ruled out...moreso for locations east of wherever the center becomes situated. To the west of the center, we're probably looking at 15g25kt winds and 3-5ft seas. Improving conditions are anticipated Tuesday late afternoon and night...though intermittent scattered tstms may be an issue throughout the week. 47

PRELIMINARY POINT TEMPS/POPS

College Station (CLL) 100 77 95 76 / 20 20 40 40 Houston (IAH) 98 78 92 78 / 20 30 80 40 Galveston (GLS) 92 82 90 82 / 30 70 90 50

HGX WATCHES/WARNINGS/ADVISORIES

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