Several ingredients will combine today to create an unstable storm environment from the Ohio Valley to the Mid-Atlantic. 

A low pressure system tracking across Ontario, Canada, will allow moisture and instability to increase over eastern Kentucky, West Virginia, and southern Ohio this afternoon. Eventually, storm activity will push into the Mid-Atlantic this evening, which includes northern Virginia and western and central Maryland. 

Large hail and high winds will be the primary threats; however, with strong winds aloft, even a couple tornadoes will be a possibility. With these threats in mind, the Storm Prediction Center has issued an Enhanced Risk for severe weather across most of West Virginia into western Virginia today. Cities in this Enhanced Risk include Charleston, W. Va., and Harrisonburg, Va. A larger Slight Risk covers the rest of Appalachia into the Mid-Atlantic, including Lexington-Fayette, Ky., Richmond, Ba., and Washington, D.C.

Thunderstorms could go well into the evening before weakening late tonight into early Tuesday morning as they track toward the East Coast. 

Be sure to know the difference between a watch and a warning. A watch means that all the ingredients for severe weather to take place are there, while a warning indicates that the severe weather has already formed, and you should take action to keep your friends and family safe. Be sure to stay up to date with your latest local forecasts, and check WeatherBug frequently for any alerts that may be issued.