Kp index — December 1964
The Kp archive
GFZ definitive record · 3-hour UTC intervals · 1932 → 2026-07-31
Max Kp
5.3
16 Dec · G1
Storm nights
2
G1×2
Time at storm level
0.8%
intervals at Kp ≥ 5−
Avg Kp
1.2
all intervals
Tap a day — its eight intervals open here.
Highlights
- G1 storm · Dec 16–17 · peak Kp 5.3
1964 · the year at a glance — storm nights by month · year peak Kp 7.7
All-time record: Kp 9.0 — reached on 27 days, most recently 2024-05-11.