Houston heat advisory escalates to excessive heat warning with weekend heat index near 115

Houston and much of Southeast Texas are under an extreme heat warning as forecasters warn that dangerous humidity and soaring temperatures could push the heat index near 114 degrees Thursday and as high as 115 degrees over the weekend.

The warning is the first extreme heat warning for Harris County since August 23, 2024, according to the Houston Chronicle. The warning is in effect until 8 p.m. Thursday, after which a heat advisory remains in place through Saturday evening.

What forecasters are saying

The Chronicle reported that the hottest part of Thursday could bring heat index values between 108 and 114 degrees. Weekend conditions may be even worse, with heat index values expected to reach 110 to 115 degrees.

Forecasters said the setup is being driven by lingering moisture left behind by Tropical Storm Arthur, along with saturated soils, strong sunshine and strengthening high pressure. Nighttime lows may stay near 80 degrees, limiting recovery overnight.

Why it matters

Heat index values above 110 degrees can become dangerous quickly, especially for older adults, children and outdoor workers. Extended heat like this also raises the risk for heat exhaustion and heat stroke.

The warning has immediate implications for anyone spending long periods outside, including event organizers and people attending FIFA World Cup-related activities in Houston during the hottest stretch.

What to watch next

Forecasters will be watching whether the warning is extended or expanded beyond Saturday, and whether weekend temperatures or dew points run hotter than expected.

Officials may also issue additional heat-related guidance or cooling-center information if conditions worsen.