Photo: Myotus · CC BY 4.0Iron Junction’s winters are colder than most of the U.S.; July afternoons average 78°
A typical July afternoon reaches 78°, a January night drops to −3°.
A year in Iron Junction at a glance
Each month’s typical high and low, and what it brings.
What stands out about Iron Junction’s climate
Compared with towns across the U.S., with Iron Junction’s place in Minnesota beside it.
What a year in Iron Junction feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 141 frost-free days a year
In half of years the last 32° night comes by May 12 and the first by October 1. Frost and day counts come from NOAA’s station at Eveleth Wwtp, MN, 5 miles from the town’s center, at about the same height.
The 2023 USDA map puts Iron Junction’s center in zone 4a: the coldest night of a typical winter, averaged over 1991–2020, reaches about −30°. Plant labels use the zone; frost dates tell you when to plant.
Freezing nights by month
Average nights at or below 32°
90° days by month
Average days at 90° or more
About 27 inches of rain a year
June is the wettest month and February the driest.
Rain + melted snow by month
Inches of water
Heating and cooling a home in Iron Junction
98% of the work is heating, so the furnace matters far more than the air conditioner. Months averaging under 55° run from October through May.
Degree days add up how far each day’s average falls below (heating) or rises above (cooling) 65° over a year. NOAA normals at Eveleth Wwtp, MN.
Living with Iron Junction’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
141 frost-free days in zone 4a. The last frost comes by May 12 in half of years, so many gardeners wait a week or two past that to set out tomatoes. The first fall frost comes by Oct 1.
Months with highs of 62–84° and lows of 40° or more: June, July, August and September.
Parks & trails →Cold waves are 63% of the yearly building losses FEMA expects in Iron Junction from natural hazards, the largest share. Normals are averages; the hazards page covers the extremes.
Natural hazards →Iron Junction and similar climates
TownRatings has no climate map of the towns around Iron Junction yet.
Temperatures and precipitation come from NOAA’s 5 km grid; snow and day counts from the stations named on this page.
Warmer than it used to be
The last 30 years in Iron Junction averaged 2.4° warmer than the 1900s. The biggest change is in December (+4.3°).
A bigger shift than in all but 162 U.S. towns.
Change by month
The two periods overlap (1991–2000 is in both), which makes the gap a little smaller than it would be between separate periods.
How Iron Junction compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Iron Junction’s place among Minnesota’s.
Iron Junction weather by month
Highs, lows and precipitation from NOAA’s grid at Iron Junction’s center. 1991–2020 normals.
| Month | High | Low | Rain + melt | 30-yr range |
|---|---|---|---|---|
| January | 17° | −3° | 0.8" | −6° – 21° |
| February | 24° | 0° | 0.7" | 1° – 28° |
| March | 37° | 14° | 1.1" | 15° – 39° |
| April | 51° | 27° | 1.8" | 30° – 47° |
| May | 65° | 39° | 3.0" | 46° – 58° |
| June | 74° | 49° | 4.3" | 57° – 67° |
| July | 78° | 53° | 3.8" | 59° – 71° |
| August | 76° | 52° | 3.5" | 58° – 68° |
| September | 67° | 44° | 3.5" | 48° – 61° |
| October | 52° | 32° | 2.6" | 34° – 47° |
| November | 35° | 19° | 1.4" | 17° – 38° |
| December | 22° | 5° | 1.0" | 1° – 23° |
| Year | 50° | 27° | 27.4" |
How much a month can swing
A normal is an average. February swings the most: from 1991 to 2020 its average ranged from 1° to 28°. August is the most reliable, staying within 10°.
Where Iron Junction’s numbers come from
Normals are 30-year averages, not a forecast. How TownRatings reads climate data →
- Temperatures and precipitation: NOAA’s gridded 1991–2020 normals for the 5 km cell at Iron Junction’s center.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Eveleth Wwtp, MN, 5 miles from the town’s center, at about the same height; the nearest station that passes our checks for distance, height and agreement with the grid.
- Growing zone: USDA Plant Hardiness Zone Map, 2023. USDA Agricultural Research Service and PRISM Group, Oregon State University, prism.oregonstate.edu/phzm, accessed 8 Oct 2026.
- Then and now: NOAA’s gridded normals for 1901–2000 at the same cell.
- Storms and extremes: FEMA National Risk Index (expected annual losses to buildings).
Common questions about Iron Junction’s climate
What is the weather like in Iron Junction?
A typical July afternoon reaches 78°, a January night drops to −3°. Colder January nights than all but 17 U.S. towns; cooler July afternoons than 96% of U.S. towns.
How cold does it get in Iron Junction in winter?
January nights average −3°. About 189 nights a year reach 32° or below and 47 reach 0° or below. In the coldest January of the last 30 years the month averaged −6°.
How hot does it get in Iron Junction?
July, with a typical high of 78° and a low of 53°. About 2 days a year reach 90° (Eveleth Wwtp, MN).
When is the first and last frost in Iron Junction?
In half of years the last spring frost (32°) comes by May 12 and the first fall frost by October 1, about 141 frost-free days, at Eveleth Wwtp, MN.
What growing zone is Iron Junction in?
Zone 4a on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about −30°.
What is the best time of year to visit Iron Junction?
By one simple rule (highs of 62–84° and lows of 40° or more), June, July, August and September. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Iron Junction getting warmer?
Yes: 1991–2020 averaged 2.4° warmer than 1901–2000 on NOAA’s grid. A bigger shift than all but 162 U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Iron Junction.
Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000; USDA/PRISM 2023 hardiness zones; FEMA National Risk Index. Today’s forecast: National Weather Service.