Weather Radar Screensaver
The Weather Radar screensaver loops live precipitation radar over your chosen region, animating the last hour of rain and snow across a dark map. The radar comes from RainViewer and the base map from CARTO — both free and key-less. It's free, runs in your browser, and ESC exits.
How the Weather Radar screensaver works
The saver is a small slippy map. It works out which map tiles cover your region at the chosen zoom using the standard Web Mercator tile maths, then fetches and composites those square tiles into the canvas.
A dark base map comes from CARTO's free tiles. Over it, the saver overlays radar tiles from RainViewer, which publishes a list of recent radar frames — roughly the past hour plus a short nowcast forecast.
Each animation step swaps in the next radar frame, so precipitation appears to sweep and evolve across the map. A timeline at the bottom shows the loop position and the timestamp of the frame on screen.
Everything is fetched live and key-less; tiles are cached as they load, so the loop runs smoothly once it has warmed up.
A worked example
Choose United States at zoom 4 and you'll see radar echoes drift west to east across the country — greens and yellows where it's raining, brighter cores in storms. Pick UK & Ireland and raise the zoom to 6 to watch fronts sweep in off the Atlantic. The last few frames are labelled 'forecast' — RainViewer's short-term nowcast.
Settings & tips
- Region centres the map; zoom sets how close in you are.
- Color scheme and radar opacity change how the precipitation looks over the map.
- Playback speed controls how fast the hour of radar loops.
Frequently asked questions
- Is the radar live?
- Yes. It loops the most recent radar frames from RainViewer — roughly the past hour plus a short nowcast — and refreshes for new frames every few minutes.
- Which regions can I watch?
- Eight presets are built in, including the United States, Europe, the UK, Japan and Australia. Pick one and adjust the zoom to taste.
- Why are the last frames labelled 'forecast'?
- RainViewer includes a short-term nowcast — a model projection of the next several minutes — after the observed frames, so the very end of the loop is a forecast.
- Does it need an internet connection?
- Yes, it streams live map and radar tiles. Offline it shows a short notice instead.
- Is the weather radar screensaver free?
- Yes, free and browser-based with no key or download. Run it fullscreen and press ESC to exit.