El Niño and South Dakota winters

In Rapid City, December through February precipitation averaged 1.11 inches during the 7 winters since 1950 that were strong El Niños, compared with 1.32 inches in other winters. 3 of the 7 strong winters finished above that other-winter average. Season snowfall at Sioux Falls averaged 41.0 inches during the 7 winters since 1950 that were strong El Niños, compared with 41.4 inches in other winters; 4 of the 7 strong winters finished above that other-winter average. In Rapid City, strong El Niño winters averaged 4.0 degrees Fahrenheit warmer than other winters.

El Niño 2026-27 tracker

El Niño winter precipitation in South Dakota

Each city row shows the average December through February precipitation in strong El Niño winters, the average in all other winters, the change, and how many strong winters finished above the other-winter average.
City	Strong average	Other average	Change	Above
Rapid City	1.11 in	1.32 in	-15%	3 of 7
Sioux Falls	2.34 in	2.13 in	+10%	5 of 7

Station figures come from GHCN-Daily (NOAA NCEI); strong winters are classified from CPC's RONI; winters cover 1950-51 through 2025-26.

El Niño snowfall in South Dakota

Each city row shows the average season snowfall in strong El Niño winters, the average in all other winters, the change, and how many strong winters finished above the other-winter average.
City	Strong average	Other average	Change	Above
Rapid City	33.1 in	42.7 in	-23%	0 of 6
Sioux Falls	41.0 in	41.4 in	-1%	4 of 7

El Niño winter temperature in South Dakota

Each city row shows the December through February mean temperature in strong El Niño winters, the mean in all other winters, and the difference.
City	Strong average	Other average	Difference (F)
Rapid City	28.9°F	24.8°F	+4.0°F
Sioux Falls	22.7°F	18.4°F	+4.3°F

Strong El Niño winters in South Dakota, winter by winter

For each city, the table shows December through February precipitation in each strong El Niño winter and the other-winter average for scale; the strong winters often disagreed.
City	1957-58	1965-66	1972-73	1982-83	1991-92	1997-98	2015-16	Other average
Rapid City	1.31	1.37	0.77	0.89	0.49	1.48	1.49	1.32
Sioux Falls	2.22	2.15	2.11	2.76	2.72	1.43	3.00	2.13

Station figures come from GHCN-Daily (NOAA NCEI); strong winters are classified from CPC's RONI; winters cover 1950-51 through 2025-26.

White Christmas odds during El Niño years, South Dakota

The share of Christmas mornings with at least 1 inch of snow on the ground, comparing strong El Niño years with all other years, shown only for cities where it ever happens.
City	Strong years	Other years
Rapid City	0%	27%
Sioux Falls	14%	48%

White Christmas odds by city

Under 17 U.S.C. 105, no copyright attaches to the government-produced figures on this page, including reports, alerts, station observations, and normals, which were created by the National Weather Service and other NOAA offices. The notice that 17 U.S.C. 403 requires appears in this sentence. It does not imply endorsement by or affiliation with those agencies. See: Data sources and attribution.

How these figures work

Strong El Niño winters here are 1957-58, 1965-66, 1972-73, 1982-83, 1991-92, 1997-98, 2015-16, classified by the Relative Oceanic Niño Index. Each city is compared against its own station record: those strong winters against every other winter since 1950. A city appears after its station reports 3 or more strong winters and 10 or more other winters.