HOUSTON – After a sweltering start to the week, hot weather is holding on across Southeast Texas, with temperatures pushing 100°F (38°C) again today. But changes are on the horizon as a tropical disturbance in the Gulf of Mexico brings an uptick in rain chances Friday and Saturday—offering a short-lived break from the heat.
This disturbance, now moving across the central Gulf, shows very low potential for development, with odds under 10% according to meteorologists. But even without cyclonic formation, it’s expected to increase moisture across Greater Houston, delivering much-needed rainfall to parts of the region.
Friday’s forecast hinges on how the system behaves as it nears the Texas Coast. Current models lean toward a coastal-heavy rain pattern, meaning places like Galveston, Brazoria, and Chambers Counties could wake up to steady showers, with scattered afternoon storms pushing slightly inland. Some isolated totals could reach 2 to 4 inches (50 to 100 mm), especially near Galveston Bay.
Saturday may bring more widespread rain. While it’s not expected to be a total washout, outdoor plans across Houston may be interrupted by numerous pop-up thunderstorms, particularly during the afternoon hours.
Rainfall amounts will likely range from 1 to 2 inches (25 to 50 mm) along the coast, tapering to 0.5 to 1 inch (13 to 25 mm) closer to the Inner Loop. Some northern and western suburbs may only see a few scattered showers or stay dry altogether.
Once the system moves through, heat returns fast. After topping out at 99°F (37°C) yesterday, today’s high could flirt again with the century mark, especially in inland neighborhoods where storms don’t develop early. The brief cooldown from cloud cover and rain Friday and Saturday will quickly vanish as hot, dry air builds back in on Sunday. Expect highs near 100°F (38°C) again by Tuesday or Wednesday of next week.
And speaking of Tuesday’s heat, it stirred up plenty of discussion around George Bush Intercontinental Airport (IAH)—officially recording 100°F (38°C) while other nearby sites reported lower numbers. The discrepancy was enough to prompt the National Weather Service to inspect the IAH sensor. The verdict? Everything checked out.
Despite claims that something was off, the IAH thermometer was reading accurately. So what happened?
Turns out, IAH sits in a naturally hot pocket, and Tuesday’s dry air played a big role. At 3 PM, relative humidity at IAH dropped to 42%, among the lowest in the metro. That dry air helped amplify heating, pushing temperatures slightly higher than nearby suburbs like Katy, Pearland, or The Woodlands, where values hovered between 96°F and 98°F (35°C–37°C).
Looking at dewpoint values, there was a noticeable bubble of lower humidity just south of the airport, a factor that likely tipped the scales. Drier air heats faster, and when combined with IAH’s location—which already tends to be warmer than other Houston sites—it created a local surge in temperature.
Is IAH a perfect reflection of Houston’s climate? Not exactly. But it remains the official point of record, and its consistency over time is what makes it valuable. Like many U.S. cities, Houston’s historical weather has migrated from downtown locations to airports, where fewer people live, but where reliable instruments and uninterrupted data collection are possible.
In this way, IAH becomes the benchmark for comparing past and present records, not necessarily a stand-in for your backyard thermometer in Midtown, Sharpstown, or Sunnyside. Still, the temperature spike Tuesday shows how urban heat islands, Gulf humidity shifts, and climate change are shaping our daily weather in unexpected ways.
