Severe Thunderstorms, Heavy Rainfall and Dangerous Heat

Severe thunderstorms are expected today and Friday from the upper Midwest, central Great Lakes into the Ohio and mid-Mississippi Valley's. In addition, heavy rainfall threat increases on Friday across the Ohio Valley. Meanwhile, early summer-like heat wave across portions of southern Texas with new daily records are forecast today and through the weekend; The heat spreads across the Gulf States. Read More >

FLASH FLOOD AND HEADWATER GUIDANCE

Flash Flood Guidance is used to predict flooding of smaller streams. Values are calculated for 1, 3, 6, 12, and 24 hour time periods for each county. Each value means: "if that amount of rainfall occurs over the given county in the given time period flooding of small streams is likely". It should be noted that these values are meant as guidance only. Just because 2 inches of rain falls in an hour in a county where the 1 hour flash flood guidance is 1.5 inches does not mean there will be flash flooding. Also it should be noted that this guidance is not applicable for urban, basement, or other flooding not associated with a stream.

Headwater Flood Guidance estimates how much rain is needed to bring selected headwater streams to flood in a given amount of time. As with flash flood guidance, these numbers are meant to be used as guidance only.

Flash Flood Guidance