Heavy Rainfall for the Mid-Atlantic; Heat and Wildfire Concerns for the West

Slow moving showers and thunderstorms may result in flash flooding for portions of the mid-Atlantic region today into tonight. Meanwhile, excessive heat will continue to build across the West through Tuesday. Heat Advisories and Extreme Heat Warnings are in effect. Fire Weather concerns continue for the interior Northwest with dry and breezy conditions. Watching the tropics across the Southeast. Read More >

Wet Bulb Globe Temperature

(Prototype -- not official -- availability not guaranteed)

New! Click here for regional and national WBGT forecasts

The Wet Bulb Globe Temperature (WBGT) is a measure of heat stress in direct sunlight, which is based on temperature, humidity, wind speed, sun angle, and cloud cover (solar radiation). This differs from the heat index, also called the apparent temperature, which is based only on temperature and humidity and is calculated for shady areas. If you work or exercise in direct sunlight, the WBGT is a good element to monitor. Scroll down for latest observations and forecasts.