G1minor

The geomagnetic storm of 31 January – 1 February 1940

On 31 January – 1 February 1940 the Kp index reached 5: a G1 (minor) storm, with 27 hours at Kp 5 or more. At its peak the lights could be seen from 280,376 places in the atlas, down to about 51° magnetic latitude.

Kp 5Peak Kp · 31 January 1940 18:00 UT

27Hours at Kp 5 or more

48Largest ap

Solar cycle 17Year 7 of solar cycle 17

Kp every three hours

56789

30 Jan31 Jan1 Feb2 Feb

Where the lights could be seen

At Kp 5 the lights reach 280,376 places of the atlas on the horizon and 80,365 overhead, down to about 51° magnetic latitude.

Countries

Russia119,505 placesSweden27,876 placesFinland24,291 placesUnited States22,332 placesCanada17,756 placesLithuania16,991 placesNorway13,111 placesLatvia7,542 placesUnited Kingdom7,329 placesBelarus6,984 places

At the edge: just within reach

ChicagoUnited StatesUfaRussiaDetroitUnited StatesVilniusLithuaniaUlyanovskRussiaRyazanRussiaVitebskBelarusBelfastUnited Kingdom

The largest towns that could see them

Before and after

Previous storm18 January 1940 · Kp 7−

Next storm20 February 1940 · Kp 5

1940

Geomagnetic storms of 1940Every storm

Geomagnetic storms since 1932Geomagnetic storm archive

Strong storms at the same time of year

4 – 8 February 1983Kp 8 · 69 h

2 – 3 February 1969Kp 8 · 30 h

1 – 4 February 1992Kp 8− · 45 h

1 – 5 February 1982Kp 7 · 75 h

4 – 5 February 1961Kp 7 · 18 h

28 – 30 January 1945Kp 7 · 21 h