Heavy to Excessive Rainfall in the Central Appalachians; Severe Weather in the Mid-South; Hot Weather in Southern California

Heavy to excessive rainfall may lead to flooding today over southwest Pennsylvania into northern West Virginia, and western Maryland. Severe thunderstorms are possible this afternoon and evening in the Mid-South and across Eastern North Carolina. An extended period of hot weather is forecast for parts of coastal southern California including Los Angeles from today through Thursday. Read More >

Flash Flood

Flooding that begins within 6 hours, and often within 3 hours, of the heavy rainfall (or other possible cause)

Flash floods are the most dangerous kind of floods, because they combine the destructive power of a flood with incredible speed. Flash floods occur when heavy rainfall exceeds the ability of the ground to absorb it, or when enough water accumulates for streams to overtop their banks, causing rapid rises of water in a short amount of time. They can happen within minutes of the causative rainfall, limiting the time available to warn and protect the public.

Flash Flood Terminology

Flash Flood Watch	Flash flooding is possible within the designated watch area -- Be alert !
Flash Flood Warning	Flash flooding has been reported or is imminent -- Take necessary precautions at once!
Small Stream Advisory	Flooding of small streams, roads and low-lying areas is occurring.
Flash Flood Statement	Follow-up information regarding flash flood event.