Iron River Threshold Days by Year (USC00473917)

18 fixed thresholds counted per year at Iron River (USC00473917): hot days, frost, tropical nights and heavy rain, with the most days in a year.

Key Facts for Iron River Thresholds

Iron River: days with a maximum temperature at or above 30 C (86 F) in 28 years, most in 1937 with 41.
Iron River: days with a maximum temperature at or below 0 C (32 F) in 28 years, most in 1926 with 119.
Iron River: nights with a minimum temperature at or below 0 C (32 F) in 27 years, most in 1946 with 201.
Iron River: nights with a minimum temperature at or below -10 C (14 F) in 27 years, most in 1943 with 102.
18 fixed thresholds have at least one qualifying day at Iron River.

Days at or above 30 C (86 F)

28 years with a qualifying day

Days per year at Iron River with a maximum temperature at or above 30 C (86 F), with the decade average as a line. The most was 41 in 1937.

Days at or above 30 C (86 F) per year at Iron River
Year	Days	Decade average
1910	35	23.6
1912	19	23.6
1916	22	23.6
1918	12	23.6
1919	30	23.6
1920	12	16.1
1921	34	16.1
1922	18	16.1
1923	21	16.1
1924	3	16.1
1925	28	16.1
1926	11	16.1
1927	7	16.1
1928	8	16.1
1929	19	16.1
1930	23	27.4
1931	28	27.4
1932	20	27.4
1933	26	27.4
1934	29	27.4
1937	41	27.4
1938	24	27.4
1939	28	27.4
1940	22	23
1943	32	23
1944	25	23
1945	17	23
1946	19	23

For each year, a bar from the first to the last day at Iron River meeting 30 C (86 F).

First to last qualifying date each year at Iron River
Year	First date	Last date
1910	1910-06-12	1910-08-21
1912	1912-06-23	1912-10-05
1916	1916-07-01	1916-08-19
1918	1918-05-05	1918-08-25
1919	1919-05-26	1919-09-07
1920	1920-05-30	1920-09-25
1921	1921-05-20	1921-09-01
1922	1922-05-10	1922-10-04
1923	1923-05-27	1923-07-31
1924	1924-07-11	1924-08-29
1925	1925-05-20	1925-09-03
1926	1926-05-05	1926-08-27
1927	1927-06-28	1927-09-14
1928	1928-06-30	1928-08-15
1929	1929-05-27	1929-09-03
1930	1930-05-21	1930-09-23
1931	1931-05-15	1931-09-12
1932	1932-05-14	1932-08-30
1933	1933-06-01	1933-09-05
1934	1934-05-09	1934-08-18
1937	1937-05-29	1937-09-23
1938	1938-06-19	1938-09-23
1939	1939-05-30	1939-09-15
1940	1940-05-12	1940-09-19
1943	1943-06-14	1943-08-30
1944	1944-05-28	1944-08-12
1945	1945-06-11	1945-09-07
1946	1946-05-28	1946-08-16

Every Fixed Threshold

Fixed thresholds at Iron River
Threshold	Years with a qualifying day	Most days in a year	Year	Latest year days
30 C (86 F): Days	28	41	1937	19
35 C (95 F): Days	18	10	1910	1
40 C (104 F): Days	1	1	1934	1
90 F (32.2 C): Days	26	24	1937	6
100 F (37.8 C): Days	3	2	1931	1
0 C (32 F): Ice days (max	28	119	1926	82
0 C (32 F): Frost days (min	27	201	1946	201
-10 C (14 F): Days with min	27	102	1943	80
-20 C (-4 F): Days with min	27	54	1912	32
-30 C (-22 F): Days with min	24	17	1912	5
-40 C (-40 F): Days with min	1	1	1912	1
20 C (68 F): Tropical nights (min	22	12	1931	1
10 mm (0.39 in): Days with 10 mm or more rain	25	30	1916	23
25 mm (0.98 in): Days with 25 mm or more rain	24	7	1916	7
50 mm (1.97 in): Days with 50 mm or more rain	4	1	1929	2
100 mm (3.94 in): Days with 100 mm or more rain	1	0	n/a	1
10 cm (3.9 in): Days with 10 cm or more snowfall	14	6	1922	4
25 cm (9.8 in): Days with 25 cm or more snowfall	1	1	1922	1

Years with under 90 percent of days observed are left out of the most days column. Threshold history at this station starts in 1910.

Download the Data

Data for Iron River 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).

Iron River Threshold Days by Year (USC00473917)

Key Facts for Iron River Thresholds

Days at or above 30 C (86 F)

Every Fixed Threshold

Download the Data

Related