Napoleon Township has cooler summers than 78% of U.S. towns
January nights here settle around 17°. Winter nights are cold: in January they are colder than in 78% of U.S. towns. December has warmed most since 1901–2000, part of a 1.6° rise. For walks and days out, the stretch from May to September brings highs of 70–82°.
A year in Napoleon Township at a glance
Each month’s typical high and low, and what it brings.
What stands out about Napoleon Township’s climate
Compared with towns across the U.S., with Napoleon Township’s place in Michigan beside it.
What a year in Napoleon Township feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 164 frost-free days a year
In half of years the last 32° night comes by May 1 and the first by October 14. Frost and day counts come from NOAA’s station at Jackson Reynolds Fld, MI, 11 miles from the town’s center, at about the same height.
The 2023 USDA map puts Napoleon Township’s center in zone 6a: the coldest night of a typical winter, averaged over 1991–2020, reaches about −8°. 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 33 inches of snow a winter
Snow, measured at Chelsea, MI, falls mostly in January. Precipitation (rain plus melted snow) adds up to 35 inches a year; May is the wettest month and February the driest. Rain or snow falls on about 123 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in Napoleon Township
91% 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 Jackson Reynolds Fld, MI.
Living with Napoleon Township’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
164 frost-free days in zone 6a. The last frost comes by May 1 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 14.
Months with highs of 62–84° and lows of 40° or more: May, June, July, August and September. 1.4 miles of trails are waiting.
Parks & trails →Of the yearly building losses FEMA expects in Napoleon Township from natural hazards, river flooding is the largest share (47%); heat waves, cold waves, winter storms and ice storms together are 12%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Napoleon Township and its neighbors
Every town next door is within a degree of Napoleon Township in January and July, closer than the 5 km grid can tell apart. Tap a town to see its climate.
Climates most like Napoleon Township’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 |
|---|---|---|---|---|
| Napoleon Township, MI | 17° | 82° | 35" | 33" |
| Pleasant Prairie, WI | 16° | 82° | 35" | 36" |
| North Dansville, NY | 17° | 82° | 33" | 36" |
| Zion, IL | 16° | 82° | 36" | 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 Napoleon Township averaged 1.6° warmer than the 1900s. The biggest change is in December (+3.3°).
A bigger shift than in 63% 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 Napoleon Township compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Napoleon Township’s place among Michigan’s.
Napoleon Township weather by month
Highs, lows and precipitation from NOAA’s grid at Napoleon Township’s center; snow, wet days and snow on the ground from Chelsea, MI. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 31° | 17° | 2.2" | 10.9" | 13 | 20 | 14° – 34° |
| February | 34° | 18° | 1.9" | 8.6" | 10 | 16 | 11° – 36° |
| March | 45° | 26° | 2.2" | 4.7" | 9 | 7 | 26° – 49° |
| April | 58° | 36° | 3.3" | 0.9" | 11 | 1 | 41° – 52° |
| May | 70° | 47° | 3.9" | 0.0" | 12 | 0 | 50° – 65° |
| June | 79° | 56° | 3.8" | 0.0" | 10 | 0 | 63° – 72° |
| July | 82° | 60° | 3.3" | 0.0" | 9 | 0 | 67° – 77° |
| August | 80° | 59° | 3.6" | 0.0" | 9 | 0 | 64° – 75° |
| September | 74° | 51° | 3.0" | 0.0" | 9 | 0 | 56° – 66° |
| October | 61° | 40° | 3.1" | 0.0" | 11 | 0 | 47° – 57° |
| November | 47° | 31° | 2.6" | 1.8" | 10 | 2 | 32° – 47° |
| December | 36° | 23° | 2.0" | 6.0" | 11 | 11 | 16° – 39° |
| Year | 58° | 38° | 34.7" | 32.9" | 123 | 56 |
How much a month can swing
A normal is an average. February swings the most: from 1991 to 2020 its average ranged from 11° to 36°. June is the most reliable, staying within 9°.
Where Napoleon Township’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 Napoleon Township’s center.
- Snow: Chelsea, MI.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Jackson Reynolds Fld, MI, 11 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 Napoleon Township’s climate
What is the weather like in Napoleon Township?
A typical July afternoon reaches 82°, a January night drops to 17°, and about 33 inches of snow falls in a normal winter. Colder January nights than 78% of U.S. towns; cooler July afternoons than 78% of U.S. towns.
How cold does it get in Napoleon Township in winter?
January nights average 17°. About 137 nights a year reach 32° or below and 7 reach 0° or below. In the coldest January of the last 30 years the month averaged 14°.
How much snow does Napoleon Township get?
About 33 inches in a normal winter at Chelsea, MI, most of it in January, with snow on the ground about 56 days a year.
How hot does it get in Napoleon Township?
July, with a typical high of 82° and a low of 60°. About 8 days a year reach 90° (Jackson Reynolds Fld, MI).
When is the first and last frost in Napoleon Township?
In half of years the last spring frost (32°) comes by May 1 and the first fall frost by October 14, about 164 frost-free days, at Jackson Reynolds Fld, MI.
What growing zone is Napoleon Township in?
Zone 6a on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about −8°.
What is the best time of year to visit Napoleon Township?
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 Napoleon Township getting warmer?
Yes: 1991–2020 averaged 1.6° warmer than 1901–2000 on NOAA’s grid. A bigger shift than 63% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Napoleon Township.
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.