Kp index — September 1991
The Kp archive
GFZ definitive record · 3-hour UTC intervals · 1932 → 2026-07-31
Max Kp
7.0
9 Sep · G3
Storm nights
10
G1×3G2×6G3×1
Time at storm level
16.3%
intervals at Kp ≥ 5−
Avg Kp
3.0
all intervals
Tap a day — its eight intervals open here.
Highlights
- G3 storm · Sep 8–10 · peak Kp 7.0
1991 · 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.