textproduct: Houston/Galveston

KEY MESSAGES

- Hot with a daily risk of isolated showers and thunderstorms along the sea breeze boundary.

- Chance of late afternoon / evening thunderstorms has increased for our northern counties on Monday.

- Slightly less hot later in the week.

DISCUSSION

Issued at 1200 AM CDT Sun Sep 20 2026

Overall, the general expected synoptic pattern over the next few days has not changed. Persistent, yet weakening, ridging should dominate the Lone Star State. The ridge will be influential enough to help skew temperatures hotter than normal. But it shouldn't be suppressive enough to prevent diurnally forced isolated showers and thunderstorms. We suspect there will be a daily risk of isolated showers/storms, particularly in our southern and coastal counties. However, the guidance is suggesting the high may erode a little more on Monday, allowing PVA from a shortwave to sneak into our region by the afternoon and evening. 00Z HRRR is even going as far as showing thunderstorm activity in our northern counties by late Monday afternoon. For this reason, I decided to add some low PoPs in our northern counties late Monday afternoon evening. We'll monitor trends in case we need to bump up PoPs during that time frame. Inland afternoon temperatures are expected to average in the mid / upper 90s through the mid-week (upper 80s to low 90s at the coast)

Not much has changed regarding expectations in the late week pattern. Guidance still suggests a deepening E CONUS trough with ridging aloft over central CONUS. This signals a continuation of hot weather, but there may be a backdoor frontal boundary that at least brings lower humidity and perhaps drops temperatures a few degrees.

Self

AVIATION

(12Z TAF Issuance) Issued at 620 AM CDT Sun Sep 20 2026

Light winds this morning will strengthen and become southeasterly during the afternoon. Isolated showers will be possible as well, though chances and coverage are currently forecast to be too low to warrant a mention with the current TAF cycle. Winds become light and variable this evening. Cloud decks lower to around 2000-3000 ft overnight into Monday morning. Outside of brief patchy fog in spots, VFR conditions should largely prevail throughout the TAF period.

03

MARINE

Issued at 1200 AM CDT Sun Sep 20 2026

Light to occasionally moderate east to southeast winds, should become more consistently moderate and from the east to northeast by the middle to later part of the week. There will be a daily risk of an isolated shower or thunderstorm through mid-week. Gulf seas are expected to be in the 1-3 foot range. However, seas may increase somewhat later in the week, possibly nearing 5 feet well offshore by Thursday.

PRELIMINARY POINT TEMPS/POPS

College Station (CLL) 97 75 98 75 / 10 0 20 20 Houston (IAH) 96 77 96 78 / 20 0 20 10 Galveston (GLS) 90 83 91 82 / 20 10 10 10

HGX WATCHES/WARNINGS/ADVISORIES

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