textproduct: Houston/Galveston

KEY MESSAGES

- High pressure will intensify through the weekend, reducing chances of rain to near zero this weekend well into next week.

- Slightly above average summertime heat (upper 90s/lower 100s) will persist through most of the rest of the month across Southeast Texas. The potential for Heat Advisory issuance remains elevated as a result.

- Without adequate precautions outdoors, cumulative impacts of heat and heat stress will remain a significant risk factor to health (especially for heat-sensitive populations).

DISCUSSION

Issued at 147 PM CDT Sat Aug 15 2026

The weather pattern will continue to be dominated by a mid-level area of high pressure that is expected to shift westward and become centered over Texas through early next week. This will continue our "rinse and repeat" pattern of hot and dry weather through the next several days. Highs will be in the low to mid 90s along the coast, with inland areas seeing highs climb to the upper 90s to around 100F.

The probabilities of of heat advisories (using an input of MaxT >102F) through next week are around 30-60% (GEFS is the more closely aligned ensemble with today's temperatures, so using this as baseline). Highest probabilities exist across the Brazos Valley/Northern Piney Woods, and across the easternmost counties (Trinity, Polk, San Jacinto, Liberty) where temperatures could reach the Advisory threshold of 103F.

Looking at the heat index side of things, deterministic guidance seems to be coming in a bit warm compared to what is being observed today, particularly the NBM (which is known to bring in higher dew points for our area). I'm hesitant to rule out heat indices getting into the Advisory range (>=108F); however, probabilities of this were lower than reaching the Advisory criteria on MaxT alone. Current thought, after looking at sounding data, is that we appear to have good mixing each day, dry air in the lower levels, and high 850mb temperatures, so this could be the reason why probabilities of reaching Advisory with MaxT are higher than reaching it with the heat index.

Scientific analysis aside, it's going to be HOT. Nighttime temperatures will not provide much relief as lows remain in the 70s to low 80s. Winds will be on the lighter side and out of the SE.

To echo the previous forecaster, continue to use caution and protect yourself from dangerously hot temperatures. Do not underestimate the effects of heat stress when working or spending time outdoors, especially with little relief expected during the nighttime hours (heat stress compounds over time). Stay hydrated, wear loose-fitting and light-colored clothing, and LOOK BEFORE YOU LOCK; never leave kids or pets unattended in vehicles. For pet owners, if the pavement is too hot for your palm, it is too hot for their paws!

As we get into the latter part of the week, closer to the weekend, rain chances increase to around 15% (decent rain chances for it being in the long-term). High pressure will continue to retrograde west into the Four Corners, and a trough across the Great lakes will deepen over the SE CONUS, putting SE Texas in the proximity of NW flow aloft. NW flow aloft has been known to trigger showers and storms over our area, and with energy moving through the 500 mb level around the same time frame, this may result in some rainfall for portions of the area. In any case, it is pretty far out in the long-term, but will continue to monitor how it evolves in the coming days.

Bailey

AVIATION

(18Z TAF Issuance) Issued at 147 PM CDT Sat Aug 15 2026

For the 15/18Z TAF update, ridging continues to control and suppress the development of much impactful convection (other than very isolated -SHRA). Typical VFR vis/cig diurnal trends will prevail outside of a window of MVFR/IFR cigs for inland KCLL/KUTS terminals by 15/10Z-15/15Z with VRB04 winds maximizing to a southerly 10 to 15 kts this afternoon and by the end of the period.

Cassel

MARINE

Issued at 147 PM CDT Sat Aug 15 2026

Light onshore winds and seas of 2-3 feet expected to continue over the next several days. Otherwise, hot and dry conditions persist.

Bailey

PRELIMINARY POINT TEMPS/POPS

College Station (CLL) 99 74 99 74 / 0 0 0 0 Houston (IAH) 97 77 97 77 / 0 0 0 0 Galveston (GLS) 90 82 89 81 / 0 0 0 0

HGX WATCHES/WARNINGS/ADVISORIES

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