Houston is starting Tuesday, August 18, with clear skies and temperatures around 79 degrees, but the relatively calm morning will give way to another dangerous afternoon. The city is expected to reach 97 degrees, with the heat index climbing as high as 105. Rain is unlikely, and there is little meaningful relief ahead.
Afternoon Heat Builds Fast
A stubborn zone of high pressure, essentially a heat dome, is keeping skies mostly sunny and rain scarce across the region. The National Weather Service expects light southwest winds Tuesday, generally between calm and 5 mph, which will do little to take the edge off the heat.
Wednesday looks even hotter, with a high near 98 degrees and heat index values up to 106. Thursday should also reach 98, while Friday and Saturday could hit 99 degrees under sunny skies. The forecast then calls for highs near 98 Sunday and 97 Monday.
Little Rain And Little Overnight Relief
Rain chances stay at 6% or lower in Houston's daily forecast through Monday. Friday and Saturday offer the best possibility for a stray shower, but the broader outlook still favors mostly dry conditions. Overnight lows will remain in the upper 70s to low 80s, so air conditioning may feel less like a luxury and more like basic infrastructure.
Inland areas north and west of Houston will run hotter, with College Station forecast near 100 degrees Tuesday, while Galveston should stay closer to 91. Patchy morning fog may also develop in some areas west of Interstate 45 before burning off after sunrise.
Heat Safety Still Matters
No watches, warnings or advisories are listed in the current forecast, but forecasters caution that the heat can still be dangerous during extended outdoor activity. Schedule strenuous work for the morning or evening, drink water, take frequent breaks in shade or air conditioning, and check on older adults, children and pets. Never leave anyone in a parked vehicle, even for a quick errand.
