Hover a row to highlight it on the map · click for the full CAP message
Layers
Radar is an optional underlay, off by default so the polygons read cleanly.
Alert types
IEM radar mosaic
The whole country, stitched from every NEXRAD site by the Iowa Environmental Mesonet. Drawing it takes any single radar off the map; for one radar, use NEXRAD Sites and click the radar.
NEXRAD sites
One radar reaches about 230 km. Pick two to combine neighbors.
Storm cells
Blue is under the alert threshold. Yellow through pink is Significant and above: the bands that can notify you.
A white ring marks a storm rated severe-likely on any hazard: damaging wind, hail or a tornado.
The solid inner cone is the rotation's, capped at 25 min because beyond that it stops being the smaller one.
Dashed behind a cell is where it has been; dotted ahead is where its motion puts it, with a bar every 15 min from the scan, not from now.
What this layer is, and how well it works →
SPC outlook
Temperature
Rainfall
Wind
From
Sustained wind at the stations, carried along as moving lines. Faster lines are brighter and warmer. Blank where too few stations report, which is most open water.
Barbs in knots. The staff points into the wind. Half barb 5, full barb 10, pennant 50; a circle is calm. Coloured by speed like the flow lines. Hover or tap a barb for the reading in your units.
Peak gusts
Each station's latest gust, smoothed between stations. Turn on Wind flow as well to see which way it is blowing.
Pressure
Pressure reduced to sea level, smoothed between stations. Lines every 4 hPa (about 0.12 inHg). Closely packed lines mean a strong gradient and wind; blue is lower than average, orange higher.
Spotter reports
Newer / less provenMore proven
Colour shows confidence: lighter = newer/less proven, darker = more proven. Tap a report for its scores.
Your places
The places saved on your account, each drawn as a pin with its name.
Sign inManage places
