Understen Threshold Days by Year (SWE00139308)

6 fixed thresholds counted per year at Understen (SWE00139308): hot days, frost, tropical nights and heavy rain, with the most days in a year.

Key Facts for Understen Thresholds

Understen: days with 10 mm (0.39 in) or more of precipitation in 23 years, most in 1960 with 18.
Understen: days with a maximum temperature at or below 0 C (32 F) in 21 years, most in 1956 with 92.
Understen: nights with a minimum temperature at or below 0 C (32 F) in 21 years, most in 1956 with 171.
Understen: nights with a minimum temperature at or below -10 C (14 F) in 19 years, most in 1956 with 43.
6 fixed thresholds have at least one qualifying day at Understen.

Nights at or below 0 C (32 F)

21 years with a qualifying day

Days per year at Understen with nights with a minimum temperature at or below 0 C (32 F), with the decade average as a line. The most was 171 in 1956.

Nights at or below 0 C (32 F) per year at Understen
Year	Days	Decade average
1951	126	132.2
1952	140	132.2
1953	107	132.2
1954	131	132.2
1955	160	132.2
1956	171	132.2
1957	122	132.2
1958	142	132.2
1959	91	132.2
1960	113	120.2
1961	97	120.2
1962	122	120.2
1963	138	120.2
1964	125	120.2
1965	130	120.2
1966	144	120.2
1967	104	120.2
1968	109	120.2
1989	76	76
1990	62	75.5
1991	89	75.5

For each year, a bar from the first to the last day at Understen meeting 0 C (32 F).

First to last qualifying date each year at Understen
Year	First date	Last date
1951	1951-01-01	1951-12-30
1952	1952-01-02	1952-12-31
1953	1953-01-01	1953-12-31
1954	1954-01-01	1954-12-31
1955	1955-01-01	1955-12-31
1956	1956-01-01	1956-12-31
1957	1957-01-01	1957-12-31
1958	1958-01-01	1958-12-31
1959	1959-01-01	1959-12-15
1960	1960-01-07	1960-12-24
1961	1961-01-01	1961-12-30
1962	1962-01-01	1962-12-31
1963	1963-01-01	1963-12-28
1964	1964-01-02	1964-12-30
1965	1965-01-02	1965-12-31
1966	1966-01-01	1966-12-29
1967	1967-01-01	1967-12-31
1968	1968-01-01	1968-11-26
1989	1989-01-01	1989-12-31
1990	1990-01-01	1990-12-31
1991	1991-01-01	1991-12-28

Every Fixed Threshold

Fixed thresholds at Understen
Threshold	Years with a qualifying day	Most days in a year	Year	Latest year days
0 C (32 F): Ice days (max	21	92	1956	30
0 C (32 F): Frost days (min	21	171	1956	89
-10 C (14 F): Days with min	19	43	1956	3
-20 C (-4 F): Days with min	2	9	1966	9
10 mm (0.39 in): Days with 10 mm or more rain	23	18	1960	6
25 mm (0.98 in): Days with 25 mm or more rain	12	2	1949	1

Years with under 90 percent of days observed are left out of the most days column. Threshold history at this station starts in 1951.

Download the Data

Data for Understen 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 2026-10-17 (17 October 2026). Threshold counts are computed by this site.

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

Understen Threshold Days by Year (SWE00139308)

Key Facts for Understen Thresholds

Nights at or below 0 C (32 F)

Every Fixed Threshold

Download the Data

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