This page does not include current Flag Conditions. Flag Conditions are determined by the WetBulb Globe Temperature (WBGT); not by air temperature. WBGT is a measure of heat stress in direct sunlight, and takes into account: temperature, humidity, wind speed, sun angle, and cloud cover. (This differs from the heat index, which is calculated for shady areas.) Color-coded flags are flown in strategic locations at military installations to communicate hazardous conditions, so that outdoor activity can be adjusted accordingly.