Kp index — September 1958
The Kp archive
GFZ definitive record · 3-hour UTC intervals · 1932 → 2026-07-31
Max Kp
8.7
4 Sep · G4
Storm nights
9
G1×5G3×2G4×2
Time at storm level
13.3%
intervals at Kp ≥ 5−
Avg Kp
2.4
all intervals
Tap a day — its eight intervals open here.
Highlights
- G4 storm · Sep 3–5 · peak Kp 8.7
1958 · 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.