The risk of flash flooding will expand from the South into the mid-Atlantic on Tuesday, threatening Atlanta, Ga., Raleigh, N.C., and Philadelphia, Pa.
An area of low pressure moving from the Tennessee Valley toward the Chesapeake Bay will pull warm, moisture-rich air from the South, providing fuel for heavy thunderstorms on Tuesday and into Tuesday night.
This is the same system that spread flooding thunderstorms across the South on Monday, causing rivers and creeks to jump their banks and roads to close due to high water.
While the threat for flash flooding is widespread, the heaviest rain will be centered from southern Virginia to central North Carolina. In this area, thunderstorms may produce 1-3 inches of rainfall.
Although the highest rainfall totals will be focused on this area, heavy thunderstorms elsewhere can still easily produce over an inch of rain in less than an hour, leading to flash flooding.
Many areas in the eastern United States have already received well above their normal amount of precipitation for the month of June.
Some cities that have already topped their monthly average include Atlanta, Ga., Charlotte, N.C., Richmond, Va. and Philadelphia, Pa.
With so many areas well above their normal rainfall for the month, flash flooding can occur rather quickly. With the ground already saturated with water, heavy rainfall will easily runoff into creeks and rivers, causing them to rise rapidly.
Small creeks can quickly turn into dangerous, fast flowing bodies of water. Caution should be used when approaching these creeks as well as roadways that are covered with water.
Story by AccuWeather.com Meteorologist Brian Lada.