G4 (Severe) Geomagnetic Storm of March 3, 1952

March 3 to 9, 1952 · 156 hours

A G4 (severe) geomagnetic storm began March 3, 1952, reached Kp 8 and lasted 156 hours, with a daily Ap as high as 94; at that Kp the aurora may be seen from about 45 degrees geomagnetic latitude.

The Kp through the storm

Began Mar 3, 12:00 UTC, peaked in the block from Mar 6, 00:00 UTC, ended Mar 10, 00:00 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: 8 (8.00)
NOAA level: G4 Severe
Duration: 156 hours
Highest daily Ap: 94
Highest 3-hour ap: 207
Rank since 1932: 131 of 4,139

How far south the aurora could have been seen

At Kp 8 NOAA’s scales put the aurora’s reach at about 45 degrees geomagnetic latitude: 37°N in the central US, 36°N in the eastern US, 39°N in the western US and 45°N in northern Europe.

NOAA says a G4 storm’s aurora has been seen as low as Alabama and northern California.

US cities within reach, the southernmost first

Nashville, TN 45.1° geomag.
Durham, NC 45.1° geomag.
Greensboro, NC 45.2° geomag.
Winston-Salem, NC 45.2° geomag.
Clarksville, TN 45.4° geomag.
Reno, NV 45.4° geomag.
Springfield, MO 45.7° geomag.
Wichita, KS 45.9° geomag.
Chesapeake, VA 46.0° geomag.
Norfolk, VA 46.0° geomag.

84 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 day	Daily Ap	Highest Kp that day
March 3, 1952	42	7-
March 4, 1952	70	6+
March 5, 1952	94	7+
March 6, 1952	82	8
March 7, 1952	58	7-
March 8, 1952	54	6
March 9, 1952	51	6

The storm before, Feb 27 The storm after, Mar 10 Every storm of 1952 The strongest on record This day in weather history Tonight’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.