Nights turn raw in Hanover each January, colder than in 91% of U.S. towns
Sunny July days climb to about 83°. By precipitation alone, it ranks drier than 71% of U.S. towns. December has warmed most since 1901–2000, part of a 1.1° rise. Keep the boiler serviced for the months from November to April, which average under 50°.
A year in Hanover at a glance
Each month’s typical high and low, and what it brings.
What stands out about Hanover’s climate
Compared with towns across the U.S., with Hanover’s place in Wisconsin beside it.
What a year in Hanover feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 170 frost-free days a year
In half of years the last 32° night comes by April 26 and the first by October 15. Frost and day counts come from NOAA’s station at Afton - Janesville Wwtp, WI, 5 miles from the town’s center, at about the same height.
The 2023 USDA map puts Hanover’s center in zone 5b: the coldest night of a typical winter, averaged over 1991–2020, reaches about −14°. 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 37 inches of snow a winter
Snow, measured at Afton - Janesville Wwtp, WI, is heaviest from January through February, about 10 inches a month. Precipitation (rain plus melted snow) adds up to 37 inches a year; June is the wettest month and January the driest. Rain or snow falls on about 127 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in Hanover
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 Afton - Janesville Wwtp, WI.
Living with Hanover’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
170 frost-free days in zone 5b. 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 15.
Months with highs of 62–84° and lows of 40° or more: May, June, July, August and September.
Parks & trails →Of the yearly building losses FEMA expects in Hanover from natural hazards, river flooding is the largest share (44%); heat waves, cold waves, winter storms and ice storms together are 21%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Hanover and similar climates
TownRatings has no climate map of the towns around Hanover yet.
Climates most like Hanover’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 |
|---|---|---|---|---|
| Hanover, WI | 12° | 83° | 37" | 37" |
| Boone, IA | 11° | 84° | 36" | 36" |
| Southport, NY | 16° | 83° | 36" | 42" |
| Kendallville, IN | 17° | 83° | 38" | 36" |
| Albion, MI | 17° | 83° | 37" | 40" |
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 Hanover averaged 1.1° warmer than the 1900s. The biggest change is in December (+2.7°).
A smaller shift than in 68% 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 Hanover compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Hanover’s place among Wisconsin’s.
Hanover weather by month
Highs, lows and precipitation from NOAA’s grid at Hanover’s center; snow, wet days and snow on the ground from Afton - Janesville Wwtp, WI. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | 30-yr range |
|---|---|---|---|---|---|---|
| January | 28° | 12° | 1.5" | 10.8" | 10 | 10° – 33° |
| February | 33° | 16° | 1.6" | 10.1" | 9 | 12° – 36° |
| March | 45° | 26° | 2.1" | 4.1" | 10 | 27° – 50° |
| April | 59° | 36° | 3.6" | 1.3" | 12 | 38° – 54° |
| May | 71° | 48° | 4.2" | 0.0" | 13 | 53° – 65° |
| June | 80° | 58° | 5.3" | 0.0" | 13 | 66° – 73° |
| July | 83° | 62° | 4.0" | 0.0" | 10 | 67° – 80° |
| August | 81° | 60° | 4.2" | 0.0" | 10 | 65° – 77° |
| September | 75° | 52° | 3.7" | 0.0" | 10 | 57° – 68° |
| October | 61° | 40° | 2.8" | 0.2" | 10 | 46° – 57° |
| November | 46° | 29° | 2.4" | 2.4" | 9 | 29° – 47° |
| December | 34° | 19° | 1.9" | 7.7" | 10 | 13° – 37° |
| Year | 58° | 38° | 37.3" | 36.6" | 127 |
How much a month can swing
A normal is an average. February swings the most: from 1991 to 2020 its average ranged from 12° to 36°. June is the most reliable, staying within 8°.
Where Hanover’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 Hanover’s center.
- Snow: Afton - Janesville Wwtp, WI.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Afton - Janesville Wwtp, WI, 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 Hanover’s climate
What is the weather like in Hanover?
A typical July afternoon reaches 83°, a January night drops to 12°, and about 37 inches of snow falls in a normal winter. Colder January nights than 91% of U.S. towns; cooler July afternoons than 68% of U.S. towns.
How cold does it get in Hanover in winter?
January nights average 12°. About 148 nights a year reach 32° or below and 16 reach 0° or below. In the coldest January of the last 30 years the month averaged 10°.
How much snow does Hanover get?
About 37 inches in a normal winter at Afton - Janesville Wwtp, WI, heaviest from January through February, about 10 inches a month.
How hot does it get in Hanover?
July, with a typical high of 83° and a low of 62°. About 13 days a year reach 90° (Afton - Janesville Wwtp, WI).
When is the first and last frost in Hanover?
In half of years the last spring frost (32°) comes by April 26 and the first fall frost by October 15, about 170 frost-free days, at Afton - Janesville Wwtp, WI.
What growing zone is Hanover in?
Zone 5b on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about −14°.
What is the best time of year to visit Hanover?
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 Hanover getting warmer?
Yes: 1991–2020 averaged 1.1° warmer than 1901–2000 on NOAA’s grid. A smaller shift than 68% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Hanover.
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.