Kp index — September 1951
The Kp archive
GFZ definitive record · 3-hour UTC intervals · 1932 → 2026-07-31
Max Kp
8.7
26 Sep · G4
Storm nights
21
G1×6G2×7G3×5G4×3
Time at storm level
38.8%
intervals at Kp ≥ 5−
Avg Kp
3.9
all intervals
Tap a day — its eight intervals open here.
Highlights
- G4 storm · Sep 10–29 · peak Kp 8.7
1951 · the year at a glance — storm nights by month · year peak Kp 8.7
All-time record: Kp 9.0 — reached on 27 days, most recently 2024-05-11.