27-day outlook · NOAA SWPC
The next 27 nights of Kp index
WATCH
Statistically, this 4-week window matters most during October–March at higher latitudes. Use it to plan a trip, not to promise a show.
How to read the calendar
Each cell is a single night. The label is the projected Kp index from 0 (quiet) to 9 (extreme storm). NOAA's official outlook runs in 12-hour blocks; we compress to per-night for ease.
What is a "good" projected Kp?
It depends on your latitude:
- Tromsø, Reykjavík, Fairbanks: Kp ≥ 3
- Edinburgh, Anchorage, Whitehorse: Kp ≥ 5
- New York, Seattle, central Germany: Kp ≥ 7
- Madrid, Atlanta, Tokyo: Kp ≥ 8, with a strong storm
This page is in active development. Day 1 scaffold — full data and per-city 27-day views are coming in Day 7.