“Definitely more like August this week than May,” Cameron Self, a meteorologist with the National Weather Service’s office in the Houston and Galveston area, said Tuesday. A very strong ridge of high pressure over the south-central United States that is centered over the Gulf of Mexico will be responsible for the extreme heat.

Temperatures across the counties under the extreme heat warning are expected to rise to at least 105 degrees, which can cause heat-related illnesses.