textproduct: Houston/Galveston

KEY MESSAGES

Issued at 1133 PM CDT Wed Jul 16 2025

- Increasing tropical moisture will lead to increased coverage of showers and thunderstorms late Thursday through Friday with locally heavy rainfall possible.

- NHC continues to monitor a disturbance moving through the northern Gulf, giving it a 40% chance of development into a tropical system within the next 2 days. Regardless of development, increased rain chances are likely late Thursday through Friday with some lingering activity into early Saturday.

- Hot and dry weather is expected Sunday through at least mid-week next week.

DISCUSSION

Issued at 1133 PM CDT Wed Jul 16 2025

Our brief period of drier conditions will persist through at least the first half of Thursday, but moisture associated with a disturbance currently moving through the northern Gulf will bring rain chances back to the region starting Thursday night. To learn more about the potential tropical aspect of the aforementioned system, check out the tropical section below. Regardless of development, we can expect an increase in shower and thunderstorm activity. There is a chance for some isolated showers or storms as early as Thursday afternoon thanks to daytime heating and the gradual increase in PWATs, but coverage will not really begin in earnest until late Thursday night into Friday as that system moves further west. Friday will have the greatest chance of showers and thunderstorms, potentially bringing locally heavy rainfall. Lingering activity will be possible through early Saturday afternoon as the disturbance turns to the north. WPC has placed the Galveston Bay region up through eastern Polk County in a Slight Risk (level 2 of 4) of excessive rainfall leading to flooding on Friday, with areas generally along and of the Brazos River in a Marginal Risk (level 1 of 4). Due to the lingering activity on Saturday, WPC continues a Marginal Risk for areas generally east of I-45.

There will likely be a sharp cutoff of rainfall totals where areas west of the Brazos River may see zero to little rainfall, while areas to the east of I-45 may end getting up to 1-2" with locally higher amounts. However, this cutoff may end up happening further east if the disturbance turns northwards earlier, or further west if the disturbance can push a little closer to SE Texas before turning northwards (and thus increasing rainfall totals overall). And unfortunately there is still uncertainty on the track of this system, but hoping there is more clarity in the forecast on Thursday. Another thing to note that may end up limiting rainfall potential is that we will be on the drier side of this disturbance, experiencing mostly a north or northeasterly fetch through the event. Continue to monitor forecast for any changes, but at this point it looks like our main impact will be the possibility of some locally heavy rainfall on Friday.

Looking beyond this disturbance, high pressure looks to build in across the Southern Plains into the Midwest Sunday through at least midweek next week bringing us hot, humid, but mostly rain- free conditions (can't out rule some afternoon thunderstorms).

Fowler

AVIATION

(00Z TAF Issuance) Issued at 554 PM CDT Wed Jul 16 2025

Light winds, mostly southerly and VFR conditions will dominate throughout the TAF period. Isolated CIGS and patchy fog could develop at times during the early morning hours, possibly introducing MVFR conditions, though any FL reductions will likely be short lived.

03

MARINE

Issued at 1133 PM CDT Wed Jul 16 2025

Light to occasionally moderate onshore winds and low seas will persist through early Thursday. There is a disorganized disturbance currently located in the northern Gulf near the Florida Panhandle that the NHC is monitoring for developing into a tropical depression (40% chance). Regardless of development, we can expect the increased rain chances late Thursday through Friday or early Saturday with locally heavy rainfall possible - though Lousiana and the coastal waters off east of High Island will have a greater chance of locally heavy rainfall. There will also likely be a slight increase in wave heights Friday into Saturday, to around 2-4ft, but could become higher if that disturbance does indeed strengthen.

Low seas and light onshore winds return Sunday and persist through at least midweek next week.

Fowler

TROPICAL

Issued at 1133 PM CDT Wed Jul 16 2025

Not much change in the tropical outlook for Invest 93L in the northern Gulf with NHC maintaining a 40% chance of development over the next 2 days. Conditions are favorable for development, but that is only if the low-level center (LLC) of the disturbance can make it over the waters. So far, the LLC (which has been hard to find on Satellite) has remained either over land or just offshore. If this system cannot either get over more open ocean, or redevelop its LLC further offshore then the likelihood it becomes a tropical system is low. 93L will continue on its western trek through the next few days, reaching southern Louisiana by late Thursday, before turning north on Friday. And if it does develop into a tropical system, its limited time over the Gulf will likely limit strengthening.

Again, regardless of development into a tropical system, an increase of moisture will lead to increased chances of showers and thunderstorms in SE Texas late Thursday through early Saturday.

Fowler

PRELIMINARY POINT TEMPS/POPS

College Station (CLL) 92 73 94 74 / 0 0 0 0 Houston (IAH) 93 75 95 78 / 0 0 10 20 Galveston (GLS) 91 80 90 80 / 0 0 10 50

HGX WATCHES/WARNINGS/ADVISORIES

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