Storm Station

Live/Radar/Thunder

Forecast map / Forecast, each 12 hours

Thunderstorm chance forecast map

Over Citizen station DW4895, Illinois, where the map opens. The whole country

The chance of a thunderstorm in each 12 hours for seven days: where storms are likely, before any radar sees them. How to read it.

Thunder on the map

What the thunder map shows

The chance of a thunderstorm in each 12 hours for seven days, in percent: where storms are likely to form, before any radar can see them.

How to read it

Under 15%
Storms unlikely.
15 to 30%
An isolated storm or two.
30 to 55%
Scattered storms.
Over 55%
Storms likely; numerous where the chance runs highest.

What it is for

  • Plan around lightning: outdoors, on the water, in the mountains.
  • See the days a severe outbreak may come.
  • Read with the radar once the storms form.

How it is made

The forecast maps are drawn from the national blend of the forecast models: the models joined into one forecast and corrected against what each place has measured, on a grid 1.6 miles across, the forecast the country’s forecasters start from. Each of its main runs, four a day, is read whole, laid onto the same grid of latitude and longitude as the radar at 2.8 miles a cell, and played forward from now.

A frame every 12 hours for 7 days, played as a loop of 3 or 7 days. As data: /radar/now.json?show=fts, the times of its frames.

Beside it

Forecast, each 12 hours

Chance of rain

For

The chance of rain or snow in each 12 hours, day and night, for seven days: when to expect it, and how surely.

0100%

Open the map

Reflectivity

Radar

Latest

Rain, snow and hail across the country now, from every radar in the national network, a new picture every five minutes.

1070 dBZ

Open the map

Echo tops

Storm tops

Latest

How tall each storm stands, in feet: the higher the top, the stronger the storm and the more likely hail and wind.

560,000 ft

Open the map