Storms of 1951

G2 (Moderate) Geomagnetic Storm of June 19, 1951

June 19, 1951 · 15 hours

A G2 (moderate) geomagnetic storm began June 19, 1951, reached Kp 6 and lasted 15 hours, with a daily Ap as high as 37; at that Kp the aurora may be seen from about 55 degrees geomagnetic latitude.

The Kp through the storm

Began Jun 19, 03:00 UTC, peaked in the block from Jun 19, 03:00 UTC, ended Jun 19, 18:00 UTC.

From 00 UT the day before to the end of the day after. Blocks in the storm are colored by level; the rest are gray.

The storm

Peak Kp
6 (6.00)
NOAA level
G2 Moderate
Duration
15 hours
Highest daily Ap
37
Highest 3-hour ap
80
Rank since 1932
1,275 of 4,139

How far south the aurora could have been seen

At Kp 6 NOAA’s scales put the aurora’s reach at about 55 degrees geomagnetic latitude: 47°N in the central US, 46°N in the eastern US, 49°N in the western US and 56°N in northern Europe.

NOAA says a G2 storm’s aurora has been seen as low as New York and Idaho.

US cities within reach, the southernmost first

  • Anchorage, AK 61.9° geomag.

1 US cities of 150,000 people or more sit at or poleward of that line. Low on the northern horizon under a dark, clear sky; not a record of sightings.

Tonight’s aurora forecast

Day by day

The daily Ap is the mean of the day’s eight three-hour ap values.

UT dayDaily ApHighest Kp that day
June 19, 1951376

More

The storm before, Jun 17The storm after, Jun 25Every storm of 1951The strongest on recordThis day in weather historyTonight’s aurora forecast

Sources

Kp and ap from GFZ Helmholtz Centre for Geosciences, Geomagnetic Observatory Niemegk, licensed CC BY 4.0: Matzka, J., Stolle, C., Yamazaki, Y., Bronkalla, O. and Morschhauser, A., 2021, The geomagnetic Kp index and derived indices of geomagnetic activity, Space Weather, doi:10.1029/2020SW002641; data doi:10.5880/Kp.0001. Storms, levels and aurora reach worked out by WeatherOverTime from those values and NOAA’s space weather scales. Definitive through August 31, 2026; later values are preliminary. Rebuilt 2026-09-24.