Kp index — 1940
The Kp archive
GFZ definitive record · 3-hour UTC intervals · 1932 → 2026-07-31
Max Kp
9.0
24 Mar · G5
Storm nights
13
G1×5G2×1G3×2G4×4G5×1
Time at storm level
21.4%
intervals at Kp ≥ 5−
Avg Kp
2.8
all intervals
Tap a day — its eight intervals open here.
Highlights
- G5 storm · Mar 23–31 · peak Kp 9.0
1940 · the year at a glance — storm nights by month · year peak Kp 9.0
All-time record: Kp 9.0 — reached on 27 days, most recently 2024-05-11.