Brown Deer School · Photo: Freekee · CC0Winter nights in Brown Deer are colder than in 86% of U.S. towns
Peak summer warmth arrives in July, with afternoons near 81°. By July afternoons alone, it runs cooler than 86% of U.S. towns. December has warmed most since 1901–2000, part of a 1.4° rise. Comfortable outdoor weather lasts from May to September, with highs of 66–81°.
A year in Brown Deer at a glance
Each month’s typical high and low, and what it brings.
What stands out about Brown Deer’s climate
Compared with towns across the U.S., with Brown Deer’s place in Wisconsin beside it.
What a year in Brown Deer feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 173 frost-free days a year
In half of years the last 32° night comes by April 26 and the first by October 18. Frost and day counts come from NOAA’s station at Mt Mary College, WI, 8 miles from the town’s center, at about the same height.
The 2023 USDA map puts Brown Deer’s center in zone 6a: the coldest night of a typical winter, averaged over 1991–2020, reaches about −9°. 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 40 inches of snow a winter
Snow, measured at Mt Mary College, WI, is heaviest from January through February, about 10 inches a month. 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 Brown Deer
90% of the work is heating, so the furnace matters far more than the air conditioner. Months averaging under 55° run from October through April.
Degree days add up how far each day’s average falls below (heating) or rises above (cooling) 65° over a year. NOAA normals at Mt Mary College, WI.
Living with Brown Deer’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
173 frost-free days in zone 6a. The last frost comes by Apr 26 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 18.
Months with highs of 62–84° and lows of 40° or more: May, June, July, August and September. 0.9 miles of trails are waiting.
Parks & trails →Of the yearly building losses FEMA expects in Brown Deer from natural hazards, river flooding is the largest share (47%); heat waves, cold waves, winter storms and ice storms together are 46%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Brown Deer and its neighbors
Every town next door is within a degree of Brown Deer in January and July, closer than the 5 km grid can tell apart. Tap a town to see its climate.
Climates most like Brown Deer’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 |
|---|---|---|---|---|
| Brown Deer, WI | 14° | 81° | 34" | 40" |
| Milford, MI | 15° | 82° | 33" | 36" |
| Corning, NY | 15° | 81° | 36" | 47" |
| Kendallville, IN | 17° | 83° | 38" | 36" |
| Sayre, PA | 17° | 84° | 37" | 35" |
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 Brown Deer averaged 1.4° warmer than the 1900s. The biggest change is in December (+3.1°).
A bigger shift than in 50% 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 Brown Deer compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Brown Deer’s place among Wisconsin’s.
Brown Deer weather by month
Highs, lows and precipitation from NOAA’s grid at Brown Deer’s center; snow, wet days and snow on the ground from Mt Mary College, WI. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 29° | 14° | 1.6" | 11.0" | 10 | 20 | 11° – 33° |
| February | 33° | 17° | 1.5" | 9.9" | 9 | 17 | 13° – 35° |
| March | 43° | 26° | 2.0" | 5.3" | 9 | 7 | 26° – 49° |
| April | 55° | 35° | 3.7" | 1.5" | 12 | 1 | 36° – 50° |
| May | 66° | 45° | 3.7" | 0.0" | 13 | 0 | 50° – 61° |
| June | 76° | 55° | 4.3" | 0.0" | 11 | 0 | 62° – 71° |
| July | 81° | 61° | 3.5" | 0.0" | 10 | 0 | 66° – 78° |
| August | 79° | 60° | 3.7" | 0.0" | 10 | 0 | 65° – 75° |
| September | 73° | 53° | 3.1" | 0.0" | 9 | 0 | 56° – 67° |
| October | 60° | 41° | 2.8" | 0.0" | 11 | 0 | 46° – 57° |
| November | 46° | 30° | 2.1" | 2.0" | 9 | 2 | 29° – 47° |
| December | 35° | 20° | 1.8" | 9.8" | 10 | 12 | 15° – 38° |
| Year | 56° | 38° | 33.7" | 39.5" | 120 | 58 |
How much a month can swing
A normal is an average. December swings the most: from 1991 to 2020 its average ranged from 15° to 38°. June is the most reliable, staying within 9°.
Where Brown Deer’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 Brown Deer’s center.
- Snow: Mt Mary College, WI.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Mt Mary College, WI, 8 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 Brown Deer’s climate
What is the weather like in Brown Deer?
A typical July afternoon reaches 81°, a January night drops to 14°, and about 40 inches of snow falls in a normal winter. Colder January nights than 86% of U.S. towns; cooler July afternoons than 86% of U.S. towns.
How cold does it get in Brown Deer in winter?
January nights average 14°. About 134 nights a year reach 32° or below and 11 reach 0° or below. In the coldest January of the last 30 years the month averaged 11°.
How much snow does Brown Deer get?
About 40 inches in a normal winter at Mt Mary College, WI, heaviest from January through February, about 10 inches a month, with snow on the ground about 58 days a year.
How hot does it get in Brown Deer?
July, with a typical high of 81° and a low of 61°. About 17 days a year reach 90° (Mt Mary College, WI).
When is the first and last frost in Brown Deer?
In half of years the last spring frost (32°) comes by April 26 and the first fall frost by October 18, about 173 frost-free days, at Mt Mary College, WI.
What growing zone is Brown Deer in?
Zone 6a on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about −9°.
What is the best time of year to visit Brown Deer?
By one simple rule (highs of 62–84° and lows of 40° or more), May, June, July, August and September. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Brown Deer getting warmer?
Yes: 1991–2020 averaged 1.4° warmer than 1901–2000 on NOAA’s grid. A bigger shift than 50% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Brown Deer.
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.