Ironwood, MI Climate: Temperature & Rain by Month
Average temperature and precipitation from NOAA NCEI 1991–2020 normals →, with a derived climate comfort score
30-year climate normals (1991-2020) from Ironwood's primary NOAA station, IRONWOOD - 2 stations mapped to the area.
The climate verdict for Ironwood
Ironwood, Michigan has a mixed annual climate rather than one dominant extreme. Its NOAA normal shows an annual average of 40°F. At 44/100 (moderate) the climate comfort score falls in the bottom third of the station-mapped U.S. score corpus, exceeding only 10% of scores.
- 40°F
- average temperature, NOAA 1991-2020 normal
- 44/100
- comfort score, above 10% of station-mapped location scores
- 37.4"
- annual precipitation · 186" snow
- 134 days
- frost-free days per growing season
Ironwood: NOAA 1991-2020 normals describe a typical year, not a forecast. Method: /methodology.
Normals record plate
Sheet USC00204104 · Ironwood, MI 40°F mean · 37.4" precip
TEMP-COOL · RANK-COOL · PHOTO-FINISH · PRCP-MID · SWING-WIDE · COMF-LOW · LOAD-HEAT · STN-MULTI · BOOK-FULL
- TEMP-COOL 40°F
- RANK-COOL #412
- PHOTO-FINISH ≈ Willow Rsvr
- PRCP-MID 37.4"
- SWING-WIDE 54°F
- COMF-LOW 44/100
- LOAD-HEAT 9,263 HDD
- STN-MULTI USC00204104
- BOOK-FULL 6/6 fields
Nearest mean-temperature peer: Willow Rsvr, WI (+ 0 °F mean)
Instrument codes from this station's NOAA 1991–2020 normals, mean temperature, corpus warmth rank, photo-finish peer station, precipitation band, seasonal swing, comfort composite, degree-day load, and field book, not a livability rating.
Mean-temperature neighbourhood
Nationwide NOAA normal poles and nearest peers, not a reprint of every MI station list.
- Ironwood (this station) 40°F
- Cold Rhinelander, WI 40°F
- Hot Albion, MT 40°F
- Near Willow Rsvr, WI 40°F
- Near Eagle Rvr, WI 40°F
Climate Living Index · Ironwood
Ironwood: 26/100 · grade F
Ironwood publishes 5 of 6 Living Index dimensions (NOAA annual/seasonal normals · NOAA daily multivariate normals); 1 missing weight rescale to 100.
PlainClimate-derived for Ironwood, not an official NOAA rating. Rankings still use Comfort Score 44/100 (separate formula). Breakpoints and limits.
| Dimension | Station value | Score |
|---|---|---|
| Precipitation balance | 37.4 in · 2.4 from 35 in | 91/100 · A |
| Normal heat + freeze calendar | 183 calendar days | 23/100 · F |
| Frost-free season | 134 days/year | 15/100 · F |
| Annual temperature balance | 40.2°F · 27.3° from 67.5°F | 5/100 · F |
| Snowfall burden | 185.5 inches/year | 0/100 · F |
Ironwood · 2026-08-04 · NOAA NCEI Climate Normals · method · Comfort Score method.
Ironwood is a continental Köppen climate: Dfb
Coldest-month mean 12.0°F and warmest-month mean 66.1°F place this station in continental, no dry season, warm summer climates (Dfb). Class Dfb is the Peel et al. (2007) label for this station's monthly mean temperature and precipitation normals: continental, specifically continental, no dry season, warm summer.
- Köppen code
- Dfb
- Group
- Continental
- Warmest month
- 66.1°F
- Coldest month
- 12.0°F
Source: official public datasets monthly normals (1991–2020) at the city’s primary station. This is a station classification, not a mapped regional consensus.
National standing · heating-led station
Where Ironwood sits across the climate record
Three NOAA fields for Ironwood's primary station, temperature, precipitation, and seasonal swing, are ranked against every station-mapped normal that carries the same field.
- Annual temperature
- Cooler than 94%
- Among 6,861 stations, Ironwood sits in the cooler third of annual means.
- Annual precipitation
- 52nd percentile wetness
- Neither arid nor torrential versus 6,352 station totals.
- Seasonal temperature swing
- Wider than 91%
- Warmest-to-coldest month gap for Ironwood is large versus 6,861 complete station-years.
How Ironwood compares across U.S. station-mapped locations
Ironwood's comfort score vs. all station-mapped locations
PlainClimate composite comfort index (1–100), NOAA 1991–2020 normals
44 10th percentile score exceeds 10% of 6,189 station-mapped location scores
- 0–10: 0 station-mapped locations (0%). Below this entry.
- 10–20: 0 station-mapped locations (0%). Below this entry.
- 20–30: 96 station-mapped locations (2%). Below this entry.
- 30–40: 280 station-mapped locations (5%). Below this entry.
- 40–50: 1,113 station-mapped locations (18%). This entry sits in this band.
- 50–60: 1,329 station-mapped locations (21%). Above this entry.
- 60–70: 1,236 station-mapped locations (20%). Above this entry.
- 70–80: 650 station-mapped locations (11%). Above this entry.
- 80–90: 921 station-mapped locations (15%). Above this entry.
- 90–100: 564 station-mapped locations (9%). Above this entry.
Source NOAA U.S. Climate Normals, PlainClimate comfort index · 1991–2020
Ironwood's measured station temperature trend
MethodologyAcross 107 complete annual observations from 1903 to 2025, IRONWOOD warmed at a fitted rate of 0.14°C per decade. The line shows the fitted change relative to its first year, not raw year-to-year temperatures or a forecast.
- Ironwood primary station fitted change +0.14 °C/decade
Monthly Temperatures
Average daily high and low temperatures by month
| Month | Avg High | Avg Low | Mean | Precip | Snow | Freeze Days | 90°F+ Days |
|---|---|---|---|---|---|---|---|
| January | 20°F (-7°C) | 4°F (-16°C) | 12°F (-11°C) | 2.0" | 43.1" | 30.9 | 0.0 |
| February | 25°F (-4°C) | 5°F (-15°C) | 15°F (-10°C) | 1.5" | 30.9" | 27.6 | 0.0 |
| March | 36°F (2°C) | 14°F (-10°C) | 25°F (-4°C) | 2.0" | 23.9" | 28.5 | 0.0 |
| April | 48°F (9°C) | 28°F (-2°C) | 38°F (3°C) | 3.1" | 11.7" | 22.2 | 0.0 |
| May | 63°F (17°C) | 41°F (5°C) | 52°F (11°C) | 3.8" | 1.9" | 6.2 | 0.1 |
| June | 72°F (22°C) | 51°F (11°C) | 62°F (17°C) | 3.9" | 0.0" | 0.2 | 0.3 |
| July | 76°F (25°C) | 56°F (13°C) | 66°F (19°C) | 4.2" | 0.0" | 0.0 | 0.8 |
| August | 75°F (24°C) | 54°F (12°C) | 64°F (18°C) | 3.8" | 0.0" | 0.0 | 0.4 |
| September | 67°F (19°C) | 46°F (8°C) | 57°F (14°C) | 3.8" | 0.3" | 1.7 | 0.0 |
| October | 53°F (11°C) | 35°F (2°C) | 44°F (7°C) | 4.0" | 6.0" | 13.5 | 0.0 |
| November | 37°F (3°C) | 23°F (-5°C) | 30°F (-1°C) | 2.9" | 24.1" | 25.4 | 0.0 |
| December | 25°F (-4°C) | 11°F (-12°C) | 18°F (-8°C) | 2.4" | 43.6" | 30.7 | 0.0 |
The year, day by day
Summer here tops out rather than builds: the warmest normal high is 77°F around July 16, short of 90°F on every date, while 183 dates carry a normal low at or below freezing, the coldest 2°F near January 28.
The freezing stretch
The normal low stays at or below 32°F into April 24, then returns to freezing around October 25, covering 183 dates in all.
Derived from the normal daily minimum. This is a different measure from the 50%-probability frost dates shown elsewhere on this page, which come from NOAA’s frost product.
Where the wet dates fall
The likeliest wet date is January 11, when 58% of years recorded at least a hundredth of an inch. The driest is August 10 at 38%. Summed across the calendar, that is about 170 wet dates a year.
The widest day
May 21 carries the biggest normal gap between afternoon and dawn, 22°F between the normal high and the normal low.
Look up any date
Any date's 1991–2020 normal for Ironwood.
Where Ironwood Stands Nationally
Freezing is routine here by normals standards — the normal low reaches 32°F or colder on about 183 nights a year, more than most ranked stations.
Days and nights track unusually close together; the widest normal swing, about 22°F, is narrower than most stations record.
Ironwood earns 2 nationally notable standings (outer quintiles) against 6,860 NOAA 1991–2020 normals stations; only those extremes render.
Monthly Precipitation
Average monthly rainfall and snowfall
Snow: 43.1"
18.1 days with precipitation
Snow: 30.9"
13.6 days with precipitation
Snow: 23.9"
12.5 days with precipitation
Snow: 11.7"
12.8 days with precipitation
Snow: 1.9"
13.4 days with precipitation
13.2 days with precipitation
12.9 days with precipitation
11.8 days with precipitation
Snow: 0.3"
13.9 days with precipitation
Snow: 6.0"
15.6 days with precipitation
Snow: 24.1"
14.8 days with precipitation
Snow: 43.6"
16.8 days with precipitation
Ironwood spreads its precipitation across the year
Neither half of the year dominates here: June through August take 32% of the annual total and December through February 16%, with neither reaching the 35% that would mark a distinct wet season. Ironwood has no dry season to plan around, though it does carry a wide 54.1°F gap between its warmest and coldest month.
The gap between the wettest and driest month still matters: July averages 4.2" and February 1.5". The three wettest months together take 33% of the year, against the 25% a perfectly flat distribution would give them.
Shares are computed from this station's own 1991-2020 monthly precipitation normals. "Spread across the year" means neither the June-August nor the December-February share reaches 35%; it describes an average year, not the variability of any single one.
How Ironwood's precipitation splits across the calendar
About 169 days a year record measurable precipitation here, carrying 37.4" between them, or roughly 0.22 inches on a typical wet day. That sits in the middle band: neither the many-light-days pattern of the Pacific Northwest and the Great Lakes, nor the few-heavy-events pattern of the Gulf and the desert Southwest.
A wet day is one recording at least 0.01 inches. These are 1991-2020 normals: they describe an average year and say nothing about the heaviest single storm on record.
Winter brings real snow to Ironwood
Ironwood averages 185.5 inches of snowfall a year, with December the snowiest month on the normals, spread across roughly 80 days that record measurable snow. That is depth accumulating on the ground, which is why it can exceed the annual precipitation figure: precipitation counts the liquid the snow melts down to, and fresh snow is mostly air.
- Annual snowfall: 185.5 inches of depth.
- Days recording measurable snow: about 80 a year.
- At a rough ten-to-one melt ratio, snow accounts for on the order of 50% of the year's precipitation.
NOAA 1991-2020 normals. The ten-to-one ratio is a convention, not a measurement: real ratios vary with temperature, so treat the share as an order of magnitude rather than an exact split.
Frost Dates & Growing Season
First Fall Freeze
October 1
50% probability date
Last Spring Freeze
May 20
50% probability date
Growing Season
134 days
Heating & Cooling Degree Days
Annual totals indicate energy demand for heating and cooling
Heating Degree Days
9,263
Higher = more heating needed
Cooling Degree Days
256
Higher = more cooling needed
Warmest Month
July
Coldest Month
January
Nationwide similar cities
Other rankable U.S. places outside MI closest to Ironwood on two NOAA annual-normal axes (mean temperature and annual precipitation). Chip rows use distinct link sets.
Closest by average temperature
Nearest out-of-state peers by annual mean temperature (40°F here).
- Crosby, ND 40°F · 0.0°F off
- Libby, MT 40°F · 0.0°F off
- Scobey, MT 40°F · 0.0°F off
- Wadena, MN 40°F · 0.0°F off
Closest by annual precipitation
Nearest out-of-state peers by annual precipitation (37.4" here), excluding temperature-peer places.
- Grand Meadow, MN 37.4" · 0.0" off
- Independence, IA 37.4" · 0.0" off
- Hurley, WI 37.4" · 0.0" off
- Bryan, OH 37.4" · 0.0" off
Snow and freeze rhythm
When cold and snow define Ironwood
heating led · moderate · mid swing
Ironwood's energy balance leans toward cold weather: 9,263 annual heating degree days against 256 for cooling. Its 54.1°F seasonal range still makes the monthly rows more useful than the annual average alone.
Only about 134 days are frost-free in a normal year. That short interval is consistent with the cold-season signal, but the measure does not predict the exact first or last freeze in any one year.
-
1. Ironwood coldest normal
January
Averaging 12°F (-11°C), this month sits below freezing for the month as a whole, not merely overnight.
-
2. Ironwood typical freeze period
January through December
The station reports average freezing days from January through December.
-
3. Ironwood snow peak
December
Ironwood averages 185.5 inches of snow a year, with December the snowiest month on the normals.
Questions about Ironwood's climate
How much snow does Ironwood get? ▼
How cold does Ironwood get in winter? ▼
How much energy does heating and cooling require in Ironwood? ▼
Data Sources
Data source: NOAA U.S. Climate Normals v1.0.1 (1991-2020). All figures on this page are from Ironwood's primary station: IRONWOOD (USC00204104). 2 NOAA stations are mapped to the Ironwood area; the primary station's record is used for consistency. For informational purposes only.
Place identity: U.S. Census Bureau 2024 Gazetteer places. The 2024 Census Gazetteer identifies the exact name-and-state match as an incorporated place (GEOID 2641060). Match rule for Ironwood: exact normalized name + state only, no fuzzy expansion, so nearby differently spelled facilities stay unmatched.
On this page every temperature, precipitation, and derived score for Ironwood comes from its primary NOAA station record. No figure on this page is typed in by an editor - each value is rendered from NOAA 1991-2020 U.S. Climate Normals. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of 1991–2020 normals.