Latest Heat Index Values
Map updates automatically at the bottom of each hour.
map of latest heat index values

Heat Index / Heat Disorders
Heat Index Possible disorders for people in higher risk groups
130+ Heat stroke / sun stroke highly likely with continued exposure.
105 - 130 Sun stroke, heat cramps, or heat exhaustion likely, and heat stroke possible with prolonged exposure and/or physical activity.
90 - 105 Sun stroke, heat cramps and heat exhaustion possible with prolonged exposure and/or physical activity.
80 - 90 Fatigue possible with prolonged exposure and/or physical activity.

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