Record envelope, standing records and threshold days for Iron River (USC00473917), Wisconsin, United States, with 39 years of record.
Key Facts for Iron River
Iron River (USC00473917) is a weather station in Wisconsin, United States at 46.58 latitude and -91.40 longitude, 336 m (1,102 ft) above sea level.
The station reports from 1909 to 1947, 39 years of record.
1,464 records set at Iron River still stand.
Records are tracked for tmax, tmin, prcp: an element needs 30 years of data to be eligible.
Iron River tied a daily record low minimum temperature of -7.8 C (18.0 F) on 27 April 1947.
About the Station
Location: Wisconsin, United States, 46.58 latitude, -91.40 longitude.
Elevation: 336 m (1,102 ft).
Period of record: 1909 to 1947, 39 years.
Eligible elements: tmax, tmin, prcp.
Daily Record Envelope and 2026
0 days at or beyond a record
Record highRecord low2026 daily maximum2026 daily minimum
The band shows the record high and record low for each calendar day at Iron River. The lines show the 2026 daily maximum and minimum. 0 days in 2026 matched or passed a record. Temperatures are in degrees Celsius.
Daily record high and record low at Iron River, with 2026 drawn through them
Month
Highest record high
Lowest record low
2026 highest maximum
2026 lowest minimum
Jan
12.8 C (55.0 F)
-41.1 C (-42.0 F)
n/a
n/a
Feb
12.2 C (54.0 F)
-37.2 C (-35.0 F)
n/a
n/a
Mar
27.8 C (82.0 F)
-32.8 C (-27.0 F)
n/a
n/a
Apr
31.1 C (88.0 F)
-21.7 C (-7.1 F)
n/a
n/a
May
36.1 C (97.0 F)
-7.8 C (18.0 F)
n/a
n/a
Jun
37.8 C (100.0 F)
-4.4 C (24.1 F)
n/a
n/a
Jul
42.8 C (109.0 F)
1.7 C (35.1 F)
n/a
n/a
Aug
36.7 C (98.1 F)
0.6 C (33.1 F)
n/a
n/a
Sep
36.7 C (98.1 F)
-6.7 C (19.9 F)
n/a
n/a
Oct
30.6 C (87.1 F)
-13.3 C (8.1 F)
n/a
n/a
Nov
23.3 C (73.9 F)
-25.6 C (-14.1 F)
n/a
n/a
Dec
12.8 C (55.0 F)
-36.1 C (-33.0 F)
n/a
n/a
Which Years Hold Standing Records
1,464 standing records
Year with most
1,464 records at Iron River still stand. 1931 holds the most, with 69.
Standing records at Iron River by the year they were set
Year set
Standing records
1909
28
1910
54
1911
34
1912
56
1913
52
1915
29
1916
32
1917
35
1918
38
1919
51
1920
44
1921
36
1922
38
1923
45
1924
61
1925
49
1926
42
1927
25
1928
34
1929
48
1930
46
1931
69
1932
40
1933
49
1934
34
1935
27
1936
54
1937
25
1938
29
1939
41
1940
37
1941
39
1942
22
1943
17
1944
26
1945
43
1946
26
1947
9
All-Time Record Progression
1 new records
1 all-time records were set at Iron River between 30 August 1941 and 30 August 1941. Each dot is a new record.
When Iron River set new all-time records
Date
Kind
Detail
1941-08-30
Record daily precipitation
Record daily precipitation 146.1 mm (5.8 in)
Wettest Day of Each Month
Aug: 146.1 mm (5.8 in)
The wettest day on record for each calendar month at Iron River. The most was 146.1 mm (5.8 in) on 30 August 1941.
Record daily precipitation for each month at Iron River
Month
Record daily precipitation (mm)
Date
Jan
22.9 mm (0.9 in)
24 January 1938
Feb
25.4 mm (1.0 in)
22 February 1922
Mar
44.7 mm (1.8 in)
16 March 1945
Apr
67.6 mm (2.7 in)
20 April 1941
May
53.8 mm (2.1 in)
3 May 1944
Jun
124.5 mm (4.9 in)
24 June 1946
Jul
55.1 mm (2.2 in)
27 July 1945
Aug
146.1 mm (5.8 in)
30 August 1941
Sep
69.9 mm (2.8 in)
9 September 1929
Oct
48.3 mm (1.9 in)
30 October 1946
Nov
45.7 mm (1.8 in)
9 November 1943
Dec
33.0 mm (1.3 in)
17 December 1912
Period of Record Coverage
1909 to 1947
Complete yearUnder 90 percent of days
38 years of record at Iron River, 1909 to 1947. 10 years have data for under 90 percent of days and are left out of rankings: 1909, 1911, 1913, 1915, 1917, 1935, 1936, 1941 and others.
Cooler than the station meanWarmer than the station mean
One stripe for each of 25 complete years at Iron River, 1910 to 1946. Blue stripes are years cooler than the station's own mean of 4.8 C (40.6 F); red stripes are warmer. The coolest year was 1924, at 3.2 C (37.8 F), and the warmest was 1931, at 7.5 C (45.5 F). The strongest colour marks a difference of 2.8 C (5.0 F).
Annual mean temperature at Iron River as warming stripes, 1910 to 1946
Year
Annual mean temperature
Difference from the station mean
1910
6.1 C
+1.33 C
1912
3.8 C
-1.02 C
1916
3.7 C
-1.10 C
1918
4.6 C
-0.19 C
1919
4.9 C
+0.08 C
1920
4.7 C
-0.11 C
1921
6.2 C
+1.39 C
1922
4.9 C
+0.16 C
1923
4.6 C
-0.20 C
1924
3.2 C
-1.57 C
1925
4.6 C
-0.18 C
1926
3.5 C
-1.25 C
1927
3.8 C
-1.01 C
1928
4.1 C
-0.65 C
1929
3.4 C
-1.43 C
1931
7.5 C
+2.71 C
1932
4.7 C
-0.04 C
1933
4.7 C
-0.04 C
1937
4.8 C
-0.01 C
1938
6.0 C
+1.26 C
1939
5.7 C
+0.88 C
1940
4.8 C
+0.04 C
1944
6.0 C
+1.17 C
1945
4.2 C
-0.58 C
1946
5.2 C
+0.43 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
1909 to 1947
Yearly extremes at Iron River: 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)
1936
35.6 C (96.1 F)
38
Coldest night (TNn)
-41.1 C (-42.0 F)
1912
-32.8 C (-27.0 F)
38
Wettest day (Rx1day)
146.1 mm (5.8 in)
1941
41.0 mm (1.6 in)
38
Wettest five days (Rx5day)
206.8 mm (8.1 in)
1946
68.4 mm (2.7 in)
38
Longest dry spell (CDD)
52 days
1943
21 days
38
Hottest day (TXx)
The hottest day of the year at Iron River, 1909 to 1947. The record is 42.8 C (109.0 F) in 1936, marked on the chart; the median year is 35.6 C (96.1 F).
Hottest day (TXx) at Iron River by year
Year
Hottest day (TXx)
1909
32.2 C (90.0 F)
1910
37.2 C (99.0 F)
1911
37.2 C (99.0 F)
1912
36.1 C (97.0 F)
1913
36.1 C (97.0 F)
1915
31.1 C (88.0 F)
1916
37.2 C (99.0 F)
1917
36.7 C (98.1 F)
1918
36.7 C (98.1 F)
1919
35.6 C (96.1 F)
1920
33.3 C (91.9 F)
1921
37.8 C (100.0 F)
1922
33.9 C (93.0 F)
1923
33.3 C (91.9 F)
1924
31.1 C (88.0 F)
1925
33.9 C (93.0 F)
1926
33.3 C (91.9 F)
1927
33.3 C (91.9 F)
1928
31.7 C (89.1 F)
1929
34.4 C (93.9 F)
1930
35.6 C (96.1 F)
1931
37.8 C (100.0 F)
1932
35.6 C (96.1 F)
1933
36.1 C (97.0 F)
1934
40.6 C (105.1 F)
1935
33.9 C (93.0 F)
1936
42.8 C (109.0 F)
1937
36.1 C (97.0 F)
1938
36.7 C (98.1 F)
1939
36.1 C (97.0 F)
1940
35.0 C (95.0 F)
1941
37.2 C (99.0 F)
1942
33.9 C (93.0 F)
1943
35.6 C (96.1 F)
1944
35.0 C (95.0 F)
1945
35.0 C (95.0 F)
1946
33.3 C (91.9 F)
1947
21.1 C (70.0 F)
Coldest night (TNn)
The coldest night of the year at Iron River, 1909 to 1947. The record is -41.1 C (-42.0 F) in 1912, marked on the chart; the median year is -32.8 C (-27.0 F).
Coldest night (TNn) at Iron River by year
Year
Coldest night (TNn)
1909
-23.9 C (-11.0 F)
1910
-32.2 C (-26.0 F)
1911
-23.9 C (-11.0 F)
1912
-41.1 C (-42.0 F)
1913
-33.9 C (-29.0 F)
1915
-25.6 C (-14.1 F)
1916
-35.0 C (-31.0 F)
1917
-33.3 C (-27.9 F)
1918
-35.6 C (-32.1 F)
1919
-32.8 C (-27.0 F)
1920
-31.7 C (-25.1 F)
1921
-28.9 C (-20.0 F)
1922
-34.4 C (-29.9 F)
1923
-34.4 C (-29.9 F)
1924
-35.6 C (-32.1 F)
1925
-31.1 C (-24.0 F)
1926
-32.8 C (-27.0 F)
1927
-32.2 C (-26.0 F)
1928
-31.7 C (-25.1 F)
1929
-35.6 C (-32.1 F)
1930
-32.8 C (-27.0 F)
1931
-25.0 C (-13.0 F)
1932
-35.6 C (-32.1 F)
1933
-36.7 C (-34.1 F)
1934
-33.9 C (-29.0 F)
1935
-25.0 C (-13.0 F)
1936
-36.1 C (-33.0 F)
1937
-32.2 C (-26.0 F)
1938
-32.8 C (-27.0 F)
1939
-31.1 C (-24.0 F)
1940
-30.0 C (-22.0 F)
1941
-29.4 C (-20.9 F)
1942
-32.8 C (-27.0 F)
1943
-35.0 C (-31.0 F)
1944
-28.9 C (-20.0 F)
1945
-33.9 C (-29.0 F)
1946
-36.1 C (-33.0 F)
1947
-29.4 C (-20.9 F)
Wettest day (Rx1day)
The wettest day of the year at Iron River, 1909 to 1947. The record is 146.1 mm (5.8 in) in 1941, marked on the chart; the median year is 41.0 mm (1.6 in).
Wettest day (Rx1day) at Iron River by year
Year
Wettest day (Rx1day)
1909
36.8 mm (1.4 in)
1910
36.1 mm (1.4 in)
1911
53.6 mm (2.1 in)
1912
33.0 mm (1.3 in)
1913
38.1 mm (1.5 in)
1915
42.4 mm (1.7 in)
1916
46.5 mm (1.8 in)
1917
50.8 mm (2.0 in)
1918
30.7 mm (1.2 in)
1919
33.8 mm (1.3 in)
1920
45.7 mm (1.8 in)
1921
38.1 mm (1.5 in)
1922
40.1 mm (1.6 in)
1923
24.6 mm (1.0 in)
1924
41.4 mm (1.6 in)
1925
31.2 mm (1.2 in)
1926
34.8 mm (1.4 in)
1927
43.9 mm (1.7 in)
1928
40.6 mm (1.6 in)
1929
69.9 mm (2.8 in)
1930
58.7 mm (2.3 in)
1931
63.5 mm (2.5 in)
1932
33.8 mm (1.3 in)
1933
41.4 mm (1.6 in)
1934
26.7 mm (1.1 in)
1935
66.0 mm (2.6 in)
1936
26.7 mm (1.1 in)
1937
43.9 mm (1.7 in)
1938
35.8 mm (1.4 in)
1939
37.8 mm (1.5 in)
1940
42.2 mm (1.7 in)
1941
146.1 mm (5.8 in)
1942
30.5 mm (1.2 in)
1943
45.7 mm (1.8 in)
1944
64.3 mm (2.5 in)
1945
55.1 mm (2.2 in)
1946
124.5 mm (4.9 in)
1947
30.5 mm (1.2 in)
Wettest five days (Rx5day)
The wettest five days of the year at Iron River, 1909 to 1947. The record is 206.8 mm (8.1 in) in 1946, marked on the chart; the median year is 68.4 mm (2.7 in).
Wettest five days (Rx5day) at Iron River by year
Year
Wettest five days (Rx5day)
1909
88.8 mm (3.5 in)
1910
45.0 mm (1.8 in)
1911
85.4 mm (3.4 in)
1912
49.7 mm (2.0 in)
1913
79.0 mm (3.1 in)
1915
71.1 mm (2.8 in)
1916
69.9 mm (2.8 in)
1917
76.2 mm (3.0 in)
1918
40.9 mm (1.6 in)
1919
44.7 mm (1.8 in)
1920
93.5 mm (3.7 in)
1921
49.0 mm (1.9 in)
1922
69.3 mm (2.7 in)
1923
53.0 mm (2.1 in)
1924
52.8 mm (2.1 in)
1925
59.1 mm (2.3 in)
1926
69.1 mm (2.7 in)
1927
65.5 mm (2.6 in)
1928
60.7 mm (2.4 in)
1929
87.5 mm (3.4 in)
1930
109.3 mm (4.3 in)
1931
77.7 mm (3.1 in)
1932
59.9 mm (2.4 in)
1933
80.2 mm (3.2 in)
1934
47.7 mm (1.9 in)
1935
81.7 mm (3.2 in)
1936
55.2 mm (2.2 in)
1937
129.7 mm (5.1 in)
1938
73.2 mm (2.9 in)
1939
61.1 mm (2.4 in)
1940
67.6 mm (2.7 in)
1941
176.1 mm (6.9 in)
1942
35.8 mm (1.4 in)
1943
63.5 mm (2.5 in)
1944
63.0 mm (2.5 in)
1945
74.2 mm (2.9 in)
1946
206.8 mm (8.1 in)
1947
3.6 mm (0.14 in)
Longest dry spell (CDD)
The longest dry spell of the year at Iron River, 1909 to 1947. The record is 52 days in 1943, marked on the chart; the median year is 21 days.
Longest dry spell (CDD) at Iron River by year
Year
Longest dry spell (CDD)
1909
17 days
1910
38 days
1911
12 days
1912
22 days
1913
12 days
1915
21 days
1916
22 days
1917
27 days
1918
21 days
1919
15 days
1920
21 days
1921
22 days
1922
11 days
1923
26 days
1924
44 days
1925
27 days
1926
13 days
1927
15 days
1928
16 days
1929
20 days
1930
17 days
1931
20 days
1932
21 days
1933
19 days
1934
29 days
1935
12 days
1936
25 days
1937
17 days
1938
13 days
1939
24 days
1940
23 days
1941
23 days
1942
25 days
1943
52 days
1944
25 days
1945
22 days
1946
15 days
1947
7 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
25 years with a frost
Across 25 years with a frost, the median last spring frost at Iron River falls on 22 May and the median first autumn frost on 23 September, which leaves a median of 128 days between them.
Fitted over all years, the growing season changes by +1.3 days per decade at this station.
Frost dates and growing season at Iron River
Measure
Median, all years
Earliest period
Recent period (1910 to 1946)
Recent against earliest
Fitted trend
Last spring frost
22 May
n/a
22 May
n/a
-1.7 days per decade
First autumn frost
23 September
n/a
23 September
n/a
-0.4 days per decade
Growing days
128 days
n/a
128 days
n/a
+1.3 days per decade
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 Iron River standing records by year: CSV or JSON. Field meanings are on the data page.
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 2026-10-14 (14 October 2026). Records are computed by this site and are not official.