Boulder Junction sits near the bottom of U.S. towns for winter warmth
Peak summer warmth arrives in July, with afternoons near 77°. Seasons differ by 75°, from the coldest nights to the warmest afternoons. Its July afternoons stay fresher than in 97% of U.S. towns. Tender plants can go out after about May 25; in half of years the first frost comes by September 21.
A year in Boulder Junction at a glance
Each month’s typical high and low, and what it brings.
What stands out about Boulder Junction’s climate
Compared with towns across the U.S., with Boulder Junction’s place in Wisconsin beside it.
What a year in Boulder Junction feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 117 frost-free days a year
In half of years the last 32° night comes by May 25 and the first by September 21. Frost and day counts come from NOAA’s station at Rest Lake, WI, 9 miles from the town’s center, at about the same height.
The 2023 USDA map puts Boulder Junction’s center in zone 4a: the coldest night of a typical winter, averaged over 1991–2020, reaches about −26°. 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 75 inches of snow a winter
Snow, measured at Rest Lake, WI, falls mostly in January and December. Precipitation (rain plus melted snow) adds up to 34 inches a year; June is the wettest month and February the driest. Rain or snow falls on about 120 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in Boulder Junction
97% 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 Rest Lake, WI.
Living with Boulder Junction’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
117 frost-free days in zone 4a. The last frost comes by May 25 in half of years, so many gardeners wait a week or two past that to set out tomatoes. The first fall frost comes by Sep 21.
Months with highs of 62–84° and lows of 40° or more: June, July, August and September. 68 miles of trails are waiting.
Parks & trails →Of the yearly building losses FEMA expects in Boulder Junction from natural hazards, river flooding is the largest share (49%); heat waves, cold waves, winter storms and ice storms together are 40%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Boulder Junction and its neighbors
Every town next door is within a degree of Boulder Junction in January and July, closer than the 5 km grid can tell apart. Tap a town to see its climate.
Climates most like Boulder Junction’s, farther away
TownRatings’ own comparison of NOAA 1991–2020 normals, not a NOAA product: places of 5,000+ at least 150 miles away, one per state, closest on January low, July high, precipitation and snow.
| Town | Jan. low | July high | Precip. | Snow |
|---|---|---|---|---|
| Boulder Junction, WI | 2° | 77° | 34" | 75" |
| Presque Isle, ME | 2° | 77° | 41" | 98" |
| Virginia, MN | −3° | 78° | 28" | 69" |
| St. Johnsbury, VT | 5° | 79° | 41" | 87" |
| Beekmantown, NY | 9° | 80° | 35" | 80" |
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value. Snow and frost-free days come from the nearest weather station, so neighbors often share them.
Warmer than it used to be
The last 30 years in Boulder Junction averaged 1.4° warmer than the 1900s. The biggest change is in December (+3.2°).
A bigger shift than in 55% of 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 Boulder Junction compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Boulder Junction’s place among Wisconsin’s.
Boulder Junction weather by month
Highs, lows and precipitation from NOAA’s grid at Boulder Junction’s center; snow, wet days and snow on the ground from Rest Lake, WI. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 21° | 2° | 1.5" | 16.7" | 10 | 28 | −1° – 23° |
| February | 26° | 3° | 1.2" | 12.7" | 7 | 26 | 2° – 29° |
| March | 37° | 13° | 1.8" | 10.9" | 8 | 22 | 14° – 41° |
| April | 50° | 26° | 2.8" | 7.2" | 10 | 8 | 28° – 46° |
| May | 65° | 39° | 3.6" | 0.3" | 11 | 0 | 45° – 59° |
| June | 74° | 49° | 4.3" | 0.0" | 11 | 0 | 58° – 67° |
| July | 77° | 53° | 4.2" | 0.0" | 11 | 0 | 59° – 70° |
| August | 75° | 52° | 3.5" | 0.0" | 10 | 0 | 58° – 68° |
| September | 67° | 45° | 3.7" | 0.1" | 11 | 0 | 49° – 61° |
| October | 53° | 33° | 3.7" | 2.9" | 12 | 2 | 36° – 49° |
| November | 37° | 22° | 2.1" | 9.1" | 9 | 9 | 20° – 40° |
| December | 26° | 10° | 1.7" | 15.3" | 10 | 25 | 7° – 27° |
| Year | 51° | 29° | 34.0" | 75.2" | 120 | 120 |
How much a month can swing
A normal is an average. February swings the most: from 1991 to 2020 its average ranged from 2° to 29°. June is the most reliable, staying within 9°.
Where Boulder 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 Boulder Junction’s center.
- Snow: Rest Lake, WI.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Rest Lake, WI, 9 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 Boulder Junction’s climate
What is the weather like in Boulder Junction?
A typical July afternoon reaches 77°, a January night drops to 2°, and about 75 inches of snow falls in a normal winter. Colder January nights than all but 87 U.S. towns; cooler July afternoons than 97% of U.S. towns.
How cold does it get in Boulder Junction in winter?
January nights average 2°. About 195 nights a year reach 32° or below and 44 reach 0° or below. In the coldest January of the last 30 years the month averaged −1°.
How much snow does Boulder Junction get?
About 75 inches in a normal winter at Rest Lake, WI, most of it in January and December, with snow on the ground about 120 days a year.
How hot does it get in Boulder Junction?
July, with a typical high of 77° and a low of 53°. About 3 days a year reach 90° (Rest Lake, WI).
When is the first and last frost in Boulder Junction?
In half of years the last spring frost (32°) comes by May 25 and the first fall frost by September 21, about 117 frost-free days, at Rest Lake, WI.
What growing zone is Boulder Junction in?
Zone 4a on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about −26°.
What is the best time of year to visit Boulder 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 Boulder Junction getting warmer?
Yes: 1991–2020 averaged 1.4° warmer than 1901–2000 on NOAA’s grid. A bigger shift than 55% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Boulder 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.