More hot days in many U.S. cities

High temperatures rise and fall from one year to the next based on many factors. But overall, the average number of days when the temperature reaches 90, 95 or 100 degrees is trending upward in many cities across the U.S. These charts show the average number of days each year at one of those temperatures. The red line shows the 5-year average of those days and can help spot a trend.

SOURCE Climate Central

CREDIT Mitchell Thorson and Dinah Voyles Pulver/USA TODAY