Ellsworth AFB Weather Records (USW00024006)

Record envelope, standing records and threshold days for Ellsworth AFB (USW00024006), South Dakota, United States, with 78 years of record.

Key Facts for Ellsworth AFB

Ellsworth AFB (USW00024006) is a weather station in South Dakota, United States at 44.15 latitude and -103.10 longitude, 980 m (3,215 ft) above sea level.
The station reports from 1949 to 2026, 78 years of record.
1,464 records set at Ellsworth AFB still stand.
Records are tracked for no element yet: an element needs 30 years of data to be eligible.

About the Station

Location: South Dakota, United States, 44.15 latitude, -103.10 longitude.
Elevation: 980 m (3,215 ft).
Period of record: 1949 to 2026, 78 years.
Eligible elements: none yet.

Daily Record Envelope and 2026

35 days at or beyond a record

The band shows the record high and record low for each calendar day at Ellsworth AFB. The lines show the 2026 daily maximum and minimum. 35 days in 2026 matched or passed a record. Temperatures are in degrees Celsius.

Daily record high and record low at Ellsworth AFB, with 2026 drawn through them
Month	Highest record high	Lowest record low	2026 highest maximum	2026 lowest minimum
Jan	19.4 C (66.9 F)	-31.7 C (-25.1 F)	16.0 C (60.8 F)	-23.0 C (-9.4 F)
Feb	22.2 C (72.0 F)	-28.3 C (-18.9 F)	17.7 C (63.9 F)	-28.3 C (-18.9 F)
Mar	27.8 C (82.0 F)	-27.8 C (-18.0 F)	24.2 C (75.6 F)	-9.4 C (15.1 F)
Apr	30.0 C (86.0 F)	-14.4 C (6.1 F)	27.6 C (81.7 F)	-6.3 C (20.7 F)
May	36.1 C (97.0 F)	-6.7 C (19.9 F)	34.4 C (93.9 F)	1.2 C (34.2 F)
Jun	40.6 C (105.1 F)	-0.6 C (30.9 F)	40.0 C (104.0 F)	6.0 C (42.8 F)
Jul	42.8 C (109.0 F)	5.6 C (42.1 F)	38.0 C (100.4 F)	9.6 C (49.3 F)
Aug	40.6 C (105.1 F)	5.0 C (41.0 F)	37.3 C (99.1 F)	10.7 C (51.3 F)
Sep	39.4 C (102.9 F)	-2.8 C (27.0 F)	35.0 C (95.0 F)	4.7 C (40.5 F)
Oct	38.0 C (100.4 F)	-10.0 C (14.0 F)	38.0 C (100.4 F)	-3.9 C (25.0 F)
Nov	24.4 C (75.9 F)	-25.6 C (-14.1 F)	23.9 C (75.0 F)	-20.3 C (-4.5 F)
Dec	22.8 C (73.0 F)	-30.0 C (-22.0 F)	19.7 C (67.5 F)	-15.1 C (4.8 F)

Which Years Hold Standing Records

1,464 standing records

1,464 records at Ellsworth AFB still stand. 1951 holds the most, with 91.

Standing records at Ellsworth AFB by the year they were set
Year set	Standing records
1949	86
1950	83
1951	91
1952	58
1953	59
1954	86
1955	68
1956	69
1957	47
1958	63
1959	61
1960	59
1961	62
1962	62
1963	59
1964	56
1965	53
1966	71
1967	44
1968	76
1969	51
1970	41
2025	59

Wettest Day of Each Month

Jul: 82.0 mm (3.2 in)

The wettest day on record for each calendar month at Ellsworth AFB. The most was 82.0 mm (3.2 in) on 14 July 1969.

Record daily precipitation for each month at Ellsworth AFB
Month	Record daily precipitation (mm)	Date
Jan	12.7 mm (0.5 in)	18 January 1950
Feb	25.1 mm (1.0 in)	9 February 1955
Mar	36.3 mm (1.4 in)	3 March 1966
Apr	46.7 mm (1.8 in)	30 April 1967
May	78.5 mm (3.1 in)	14 May 1965
Jun	61.5 mm (2.4 in)	15 June 1967
Jul	82.0 mm (3.2 in)	14 July 1969
Aug	34.0 mm (1.3 in)	31 August 1951
Sep	49.0 mm (1.9 in)	13 September 1966
Oct	36.1 mm (1.4 in)	6 October 1962
Nov	16.0 mm (0.6 in)	12 November 1959
Dec	12.2 mm (0.5 in)	4 December 1960

Period of Record Coverage

1949 to 2025

23 years of record at Ellsworth AFB, 1949 to 2025. Every year has data for at least 90 percent of its days.

Days with data per year at Ellsworth AFB
Year	Days with data	Share of year	Complete
1949	365	100%	Yes
1950	364	100%	Yes
1951	365	100%	Yes
1952	365	100%	Yes
1953	365	100%	Yes
1954	365	100%	Yes
1955	364	100%	Yes
1956	362	99%	Yes
1957	362	99%	Yes
1958	364	100%	Yes
1959	365	100%	Yes
1960	366	100%	Yes
1961	365	100%	Yes
1962	365	100%	Yes
1963	365	100%	Yes
1964	366	100%	Yes
1965	364	100%	Yes
1966	361	99%	Yes
1967	363	99%	Yes
1968	364	99%	Yes
1969	332	91%	Yes
1970	363	99%	Yes
2025	347	95%	Yes

Latest Records

No records were set at this station in the latest data.

Climate Trend

22 complete years, 1949 to 2025

One stripe for each of 22 complete years at Ellsworth AFB, 1949 to 2025. Blue stripes are years cooler than the station's own mean of 8.5 C (47.4 F); red stripes are warmer. The coolest year was 1951, at 6.7 C (44.1 F), and the warmest was 2025, at 10.3 C (50.5 F). The strongest colour marks a difference of 1.9 C (3.4 F).

Annual mean temperature at Ellsworth AFB as warming stripes, 1949 to 2025
Year	Annual mean temperature	Difference from the station mean
1949	8.4 C	-0.16 C
1950	6.9 C	-1.62 C
1951	6.7 C	-1.81 C
1952	9.4 C	+0.85 C
1953	9.8 C	+1.27 C
1954	9.9 C	+1.34 C
1955	8.5 C	-0.04 C
1956	9.3 C	+0.78 C
1957	8.2 C	-0.38 C
1958	9.1 C	+0.51 C
1959	8.3 C	-0.26 C
1960	8.7 C	+0.17 C
1961	9.5 C	+0.90 C
1962	8.6 C	+0.06 C
1963	9.4 C	+0.88 C
1964	7.9 C	-0.68 C
1965	7.9 C	-0.68 C
1966	7.8 C	-0.79 C
1967	8.2 C	-0.32 C
1968	7.5 C	-1.06 C
1970	7.9 C	-0.66 C
2025	10.3 C	+1.73 C

This station does not have enough complete years (30 are needed) to fit a temperature trend.

A year is complete when all 12 months have at least 20 days of both daily maximum and daily minimum readings. The annual mean is the mean of the monthly means. The trend describes this one station over this period; it does not say what caused the change.

Extremes by Year

1949 to 2026

Yearly extremes at Ellsworth AFB: the record and the median year
Measure	Record	Year of the record	Median year	Years with a value
Hottest day (TXx)	42.8 C (109.0 F)	1966	37.8 C (100.0 F)	24
Coldest night (TNn)	-31.7 C (-25.1 F)	1949	-26.4 C (-15.5 F)	24
Wettest day (Rx1day)	82.0 mm (3.2 in)	1969	38.9 mm (1.5 in)	23
Wettest five days (Rx5day)	123.5 mm (4.9 in)	1962	67.6 mm (2.7 in)	23
Longest dry spell (CDD)	82 days	1952	33 days	23

Hottest day (TXx)

The hottest day of the year at Ellsworth AFB, 1949 to 2026. The record is 42.8 C (109.0 F) in 1966, marked on the chart; the median year is 37.8 C (100.0 F).

Hottest day (TXx) at Ellsworth AFB by year
Year	Hottest day (TXx)
1949	40.0 C (104.0 F)
1950	36.7 C (98.1 F)
1951	38.9 C (102.0 F)
1952	42.2 C (108.0 F)
1953	37.8 C (100.0 F)
1954	41.1 C (106.0 F)
1955	37.2 C (99.0 F)
1956	37.2 C (99.0 F)
1957	36.1 C (97.0 F)
1958	37.8 C (100.0 F)
1959	38.9 C (102.0 F)
1960	39.4 C (102.9 F)
1961	40.6 C (105.1 F)
1962	36.7 C (98.1 F)
1963	37.2 C (99.0 F)
1964	37.8 C (100.0 F)
1965	37.2 C (99.0 F)
1966	42.8 C (109.0 F)
1967	36.7 C (98.1 F)
1968	35.6 C (96.1 F)
1969	40.6 C (105.1 F)
1970	37.8 C (100.0 F)
2025	40.0 C (104.0 F)
2026	41.0 C (105.8 F)

Coldest night (TNn)

The coldest night of the year at Ellsworth AFB, 1949 to 2026. The record is -31.7 C (-25.1 F) in 1949, marked on the chart; the median year is -26.4 C (-15.5 F).

Coldest night (TNn) at Ellsworth AFB by year
Year	Coldest night (TNn)
1949	-31.7 C (-25.1 F)
1950	-31.1 C (-24.0 F)
1951	-28.3 C (-18.9 F)
1952	-26.7 C (-16.1 F)
1953	-22.2 C (-8.0 F)
1954	-26.1 C (-15.0 F)
1955	-22.2 C (-8.0 F)
1956	-23.3 C (-9.9 F)
1957	-28.9 C (-20.0 F)
1958	-22.2 C (-8.0 F)
1959	-26.1 C (-15.0 F)
1960	-23.9 C (-11.0 F)
1961	-22.2 C (-8.0 F)
1962	-27.8 C (-18.0 F)
1963	-30.6 C (-23.1 F)
1964	-30.0 C (-22.0 F)
1965	-25.0 C (-13.0 F)
1966	-30.0 C (-22.0 F)
1967	-27.8 C (-18.0 F)
1968	-29.4 C (-20.9 F)
1969	-26.1 C (-15.0 F)
1970	-25.0 C (-13.0 F)
2025	-28.3 C (-18.9 F)
2026	-23.7 C (-10.7 F)

Wettest day (Rx1day)

The wettest day of the year at Ellsworth AFB, 1949 to 2026. The record is 82.0 mm (3.2 in) in 1969, marked on the chart; the median year is 38.9 mm (1.5 in).

Wettest day (Rx1day) at Ellsworth AFB by year
Year	Wettest day (Rx1day)
1949	33.8 mm (1.3 in)
1950	35.6 mm (1.4 in)
1951	34.0 mm (1.3 in)
1952	33.3 mm (1.3 in)
1953	48.3 mm (1.9 in)
1954	34.5 mm (1.4 in)
1955	40.1 mm (1.6 in)
1956	34.0 mm (1.3 in)
1957	38.9 mm (1.5 in)
1958	47.0 mm (1.9 in)
1959	27.4 mm (1.1 in)
1960	34.3 mm (1.4 in)
1961	16.8 mm (0.7 in)
1962	53.1 mm (2.1 in)
1963	39.4 mm (1.6 in)
1964	36.3 mm (1.4 in)
1965	78.5 mm (3.1 in)
1966	49.0 mm (1.9 in)
1967	61.5 mm (2.4 in)
1968	58.4 mm (2.3 in)
1969	82.0 mm (3.2 in)
1970	45.7 mm (1.8 in)
2025	n/a
2026	14.5 mm (0.6 in)

Wettest five days (Rx5day)

The wettest five days of the year at Ellsworth AFB, 1949 to 2026. The record is 123.5 mm (4.9 in) in 1962, marked on the chart; the median year is 67.6 mm (2.7 in).

Wettest five days (Rx5day) at Ellsworth AFB by year
Year	Wettest five days (Rx5day)
1949	43.5 mm (1.7 in)
1950	49.1 mm (1.9 in)
1951	91.7 mm (3.6 in)
1952	69.4 mm (2.7 in)
1953	62.3 mm (2.5 in)
1954	37.3 mm (1.5 in)
1955	40.7 mm (1.6 in)
1956	35.2 mm (1.4 in)
1957	67.6 mm (2.7 in)
1958	105.1 mm (4.1 in)
1959	36.9 mm (1.5 in)
1960	55.8 mm (2.2 in)
1961	28.2 mm (1.1 in)
1962	123.5 mm (4.9 in)
1963	54.7 mm (2.2 in)
1964	78.7 mm (3.1 in)
1965	96.5 mm (3.8 in)
1966	85.7 mm (3.4 in)
1967	116.6 mm (4.6 in)
1968	78.4 mm (3.1 in)
1969	104.1 mm (4.1 in)
1970	69.6 mm (2.7 in)
2025	n/a
2026	23.8 mm (0.9 in)

Longest dry spell (CDD)

The longest dry spell of the year at Ellsworth AFB, 1949 to 2026. The record is 82 days in 1952, marked on the chart; the median year is 33 days.

Longest dry spell (CDD) at Ellsworth AFB by year
Year	Longest dry spell (CDD)
1949	54 days
1950	54 days
1951	33 days
1952	82 days
1953	47 days
1954	33 days
1955	33 days
1956	24 days
1957	44 days
1958	37 days
1959	23 days
1960	41 days
1961	41 days
1962	33 days
1963	27 days
1964	41 days
1965	22 days
1966	24 days
1967	36 days
1968	28 days
1969	38 days
1970	20 days
2025	n/a
2026	4 days

Each chart shows one value per year; the dot marks the record year. TXx is the hottest daily maximum, TNn the coldest daily minimum, Rx1day and Rx5day the largest one-day and five-day rain totals, and CDD the longest run of days with less than 1 mm of rain. A year with missing days can understate an extreme.

Frost Dates and Growing Season

22 years with a frost

Across 22 years with a frost, the median last spring frost at Ellsworth AFB falls on 4 May and the median first autumn frost on 1 October, which leaves a median of 152 days between them.

Frost dates and growing season at Ellsworth AFB
Measure	Median, all years	Earliest period	Recent period (1949 to 2025)	Recent against earliest	Fitted trend
Last spring frost	4 May	n/a	4 May	n/a	n/a
First autumn frost	1 October	n/a	1 October	n/a	n/a
Growing days	152 days	n/a	152 days	n/a	n/a

A frost day is a day with a daily minimum at or below 0 C (32 F). The last spring frost and the first autumn frost are the last and first such days of the cold season, and growing days are the days between them. A negative trend for the last spring frost means it comes earlier.

Download the Data

Data for Ellsworth AFB standing records by year: CSV or JSON. Field meanings are on the data page.
Data for Ellsworth AFB threshold days by year: CSV or JSON. Field meanings are on the data page.

Source: NOAA National Centers for Environmental Information, Global Historical Climatology Network Daily (GHCN-Daily). Records are computed by World Extreme Weather Monitor and are not official NOAA products. (US Government open data (NOAA NCEI)) Data as of 2026-10-14 (14 October 2026). Records are computed by this site and are not official.

Data as of 2025-12-31. Last revised 31 December 2025 (2025-12-31).