Forecast FAQ

Interpreting The Map

Each shape on the map represents a risk area where tornadoes are possible on a specific day. These areas are labeled with a day of the week using the following convention:

M = Monday
Tu = Tuesday
W = Wednesday
Th = Thursday
F = Friday
Sa = Saturday
Su = Sunday

Each risk area is valid from 12z of the forecast day to 12z of the next day, with the exception of the Day 1 forecast, which is valid from the time the forecast is issued to 12z the next day.

Discussion Details

TORNADO RANGE – How many tornadoes are expected.

[OLD] POTENTIAL (used in 2012 and 2013 forecasts) – Describes the amount of tornadoes possible within the risk area(s). The categories are:

Very low – One or no tornadoes expected.
Low – Two or less tornadoes expected.
Medium – One to several tornadoes expected.
High – At least several tornadoes expected.

CONFIDENCE – Portrays the amount of certainty in the potential and timing/placement of the risk area. The categories are low, normal and high.

TORNADO OUTBREAK – A day in which six or more tornadoes are expected.


U.S. Tornadoes does not issue official forecasts and claims no liability in any decisions or actions that may be based on our forecasts or discussions on any platform. The official sources for tornado forecasts are the Storm Prediction Center and the National Weather Service.

While the tornado threat forecast could remain accurate through several days, the forecast can and often does change from day to day. Forecasts are only truly valid during the day they are issued. Short term updates may be issued between the scheduled forecasts, but if there aren’t, you should refer to the Storm Prediction Center’s Convective Outlooks page for forecast updates.

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