HeatStorms.org: tracking the biggest heat in North America
Heat storms are heat waves grown huge: abnormal heat spread across vast regions at once. See where the risk is today, which areas are under heat alerts, and how your own forecast compares to normal.
Heat across North America
Active heat alerts
Official alerts: US (weather.gov) · Canada (weather.gc.ca)How hot is it where you are?
Enter a city or ZIP in the US, Canada or Mexico to compare this week’s highs with normal for the date.
Normal = average daily high for the same dates, 1991–2020. Forecast and history from Open-Meteo.com.
From hot day to heat storm
Hot day
A single day hotter than normal for that place and time of year.
Heat wave
Abnormal heat that holds for days in a row over one area.
Heat storm
A heat wave so large it sprawls across many states or regions at once, tracked and named like a hurricane.
Cascade
Heat storms that overlap or follow one another with no break between them.
Get a heads-up before the heat hits
One email when a heat storm forms or heads your way. No spam.