If you’re traveling for the Fourth of July, prepare for more than just crowds—you may also be walking into some dangerous heat.
A large dome of high pressure will dominate much of the country through Independence Day, bringing widespread above-average temperatures from the Plains to the East Coast. Many cities will climb into the upper 90s or above 100 degrees Saturday afternoon, making it one of the hottest holiday weekends of the summer so far.
Triple-digit heat from the Plains to the East Coast:
Forecast highs on Saturday include:
- Dallas: 101°
- Oklahoma City: 101°
- Raleigh: 105°
- Phoenix: 105°
- Las Vegas: 103°
- Washington, D.C.: 99°
- New York City: 95°
- Houston: 96°
While Houston’s high of 96 degrees is certainly hot, it won’t be among the nation’s hottest locations this holiday. Instead, the most intense heat will shift east, where cities unaccustomed to prolonged heat could experience dangerous conditions.
Heat risk reaches dangerous levels:
The National Weather Service’s Heat Risk forecast paints an even more concerning picture. Much of the eastern half of the country is expected to experience Major to Extreme Heat Risk on Saturday.
This forecast doesn’t just consider the afternoon high temperature. It also accounts for humidity, warm overnight lows, and how long the heat has persisted—all factors that increase stress on the human body.
For vulnerable groups, including older adults, young children, outdoor workers, and those without reliable air conditioning, prolonged time outdoors could become dangerous.
Why it’s so hot:
The culprit is a sprawling area of high pressure centered over the Southeast.
High pressure causes air to sink, and sinking air warms and dries as it compresses. That suppresses widespread thunderstorm development while allowing abundant sunshine to heat the ground efficiently throughout the day.
Around the edges of the high, temperatures ease slightly, but much of the central and eastern U.S. will remain locked in summer heat through the holiday weekend.
Houston’s forecast:
Houston will also be hot for Fourth of July celebrations, with afternoon temperatures reaching the mid-90s and heat index values likely climbing into the low 100s. A few isolated showers may develop during the afternoon, but many communities will stay dry for fireworks and evening festivities.
If you’re celebrating outdoors—whether in Houston or traveling elsewhere—drink plenty of water, take breaks in the shade or air conditioning, wear lightweight clothing, and never leave children or pets in a parked vehicle. Even a short time inside a hot car can quickly become life-threatening.