Heat stress in Houston
Gulf humidity stacked on Texas heat: oppressive WBGT that lingers long after sunset.
Reduce exertion and hydrate frequently. Take regular shade breaks.
Wet-bulb globe temperature via the Liljegren (2008) method. This page is cached and refreshes in the background, so the live badge below can be a few minutes ahead of it.
View Houston on the live mapReading heat stress in Houston
Wet-bulb globe temperature (WBGT) is the heat measure that actually tracks danger to the body. Unlike the plain air temperature on your phone, it folds in humidity, wind, and direct sun: the factors that decide whether your sweat can still cool you. It’s the standard the military, athletic associations, and occupational-safety bodies use to call when outdoor activity is no longer safe.
That matters in Houston because gulf humidity stacked on Texas heat: oppressive WBGT that lingers long after sunset. The number above is the live outdoor WBGT for the city right now; tap through to the live map to inspect any neighborhood, scrub the forecast hour by hour, and see the 7-day outlook.
How hot Houston usually gets
Across 2015–2024, Houston averaged a 90°F daily high in summer: 48th hottest of the 174 metros we track, and August is typically the warmest month.
Most of the heat here sits below the extremes: around 58 days a year top 90°F, and only about 3 reach 100°F.
Humidity is the real story: summer averages about 78%, so sweat evaporates poorly and heat stress runs well above what a 90°F afternoon suggests.
A bad day runs well past a normal one, with 107°F recorded against a 90°F summer average.
Daily high temperatures and humidity from ERA5 reanalysis, 2015–2024 (hottest day in the sample: 2023-08-27). These are climate averages for context: the reading at the top of this page is the live one.
For school sports, UIL (University Interscholastic League) publishes UIL 2026-27 Heat Stress & Athletic Participation Required Plan, which uses wet-bulb globe temperature. Texas’s activity zones appear beside the live reading in the app. Our Texas heat policy page has the details, the source and the date we last checked it.
Heat in Houston: common questions
How hot does it usually get in Houston?
Across 2015–2024, Houston averaged a 90°F daily high through summer, with about 58 days a year at or above 90°F and 3 at or above 100°F. August is typically the hottest month, and the hottest day in that sample reached 107°F. Figures are from ERA5 daily reanalysis.
When is the hottest time of year in Houston?
August has the highest average daily high in Houston. Humidity is the real story here: summer averages about 78%, so sweat evaporates poorly and heat stress runs well above what the temperature alone suggests. Use the forecast on this page to plan around the specific days that matter.
Does Texas have a heat policy for school sports?
UIL (University Interscholastic League) publishes UIL 2026-27 Heat Stress & Athletic Participation Required Plan, which uses wet-bulb globe temperature. Texas’s activity zones appear beside the live reading in the app. Our WBGT is a modeled estimate rather than the on-site device reading a policy may call for, so check the association's own document for current requirements.
What is the WBGT in Houston right now?
The reading at the top of this page is the current wet-bulb globe temperature for Houston, Texas, computed from live weather by the Liljegren (2008) method and labeled with how recently it updated. For an exact reading at your own neighborhood, plus an hour-by-hour forecast, open the live map.
Why is WBGT more useful than the temperature for Houston?
Air temperature ignores humidity, wind, and sun: the things that decide whether heat is dangerous. Houston's climate (gulf humidity stacked on Texas heat: oppressive WBGT that lingers long after sunset.) is exactly why a single "feels-like" or thermometer reading can understate the real risk. WBGT captures all of it in one number.
When is heat most dangerous in Houston?
August is the peak month in Houston, and within a day heat stress is highest in the early-to-mid afternoon when sun load is greatest. About 58 days a year reach 90°F, so most of the risk sits in a handful of afternoons rather than across the whole season. Use the forecast on this page to find the window that works.
Put Houston’s live heat stress on your site
A self-updating WBGT badge for schools, teams, camps, and local sites: it always shows the current reading and links back here.
<iframe src="https://wetbulbtracker.com/embed/houston-tx" width="340" height="150" style="border:0" title="Live WBGT: Houston, TX" loading="lazy"></iframe>Paste it into any website. The badge updates itself and links back here. Add ?theme=light for light sites.