Monday ended both June and the year’s first half on a day that fulfilled the requirements for summer in Washington: ...

Sometimes the temperature outside feels warmer than it is, and there's a reason. Here's a breakdown of the heat index.

A public health researcher explains the signs someone is developing heat exhaustion or heat stroke, and what to do.

Residents can use the NWS Heat Index Calculator to calculate what the heat index is locally. In addition, there is the Heat Index Chart with a wider range of temperatures and humidity percentages.

The National Oceanic and Atmospheric Administration says people should start exercising “caution” when the heat index reaches ...

An 'extreme heat watch' is in effect as the heat index is expected to skyrocket. Here's timing, updated heat index values, more.

Within those constraints, finding ways to stay hydrated and lower your body temperature are paramount. You can do this by drinking lots of fluids, wetting clothing or putting cold water or a cold rag ...

The heat index explained Here's what you need to know about "feels-like" temperatures and humidity in this first heat wave of the season. To stream WUSA9 on your phone, you need the WUSA9 app.

Residents can use the NWS Heat Index Calculator to calculate what the heat index is locally. In addition, there is the Heat Index Chart with a wider range of temperatures and humidity percentages.

An 'extreme heat watch' is in effect as the heat index is expected to skyrocket. Here's timing, updated heat index values, more.

There are four classifications for heat index, according to the National Weather Service: Caution: When the heat index is 80-90 degrees, prolonged exposure to heat and physical activity can cause ...