Kp index — September 1941
The Kp archive
GFZ definitive record · 3-hour UTC intervals · 1932 → 2026-07-31
Max Kp
9.0
19 Sep · G5
Storm nights
13
G1×6G2×5G4×1G5×1
Time at storm level
12.5%
intervals at Kp ≥ 5−
Avg Kp
2.7
all intervals
Tap a day — its eight intervals open here.
Highlights
- G5 storm · Sep 18–21 · peak Kp 9.0
1941 · 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.