Green Bay, WI climate
Green Bay has cold, snowy winters and pleasant summers. A typical July afternoon reaches 78°, a January night drops to 12°, and about 48 inches of snow falls in a normal winter.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in Green Bay feels like
Winter
Spring
Summer
Fall
Green Bay weather by month
Average highs, lows, rain and snow for every month, from NOAA’s 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 26° | 12° | 1.6" | 13.5" | 9 | 24 | 8° – 31° |
| February | 29° | 14° | 1.2" | 12.6" | 7 | 24 | 10° – 32° |
| March | 39° | 23° | 1.9" | 6.2" | 7 | 14 | 21° – 45° |
| April | 50° | 33° | 3.1" | 2.4" | 9 | 1 | 34° – 48° |
| May | 63° | 44° | 3.5" | 0 | 10 | 0 | 47° – 59° |
| June | 73° | 54° | 4.0" | 0 | 9 | 0 | 60° – 68° |
| July | 78° | 60° | 3.6" | 0 | 9 | 0 | 63° – 74° |
| August | 76° | 59° | 3.4" | 0 | 9 | 0 | 63° – 72° |
| September | 69° | 51° | 3.3" | 0 | 8 | 0 | 54° – 65° |
| October | 56° | 40° | 3.1" | 0.2" | 9 | 0 | 44° – 54° |
| November | 43° | 30° | 2.2" | 2.2" | 9 | 2 | 28° – 44° |
| December | 31° | 19° | 1.8" | 11.0" | 8 | 15 | 13° – 35° |
| Year | 53° | 37° | 32.6" | 48.1" | 102 | 80 |
“Wet days” have at least 0.01" of rain or melted snow. “Snow on ground” counts days with 1" or more. The 30-year range is the coldest and warmest that month’s average temperature got between 1991 and 2020.
Rain and snow in Green Bay
Green Bay gets 33 inches of rain and melted snow a year. June is the wettest month and February the driest. Rain or snow falls on about 102 days a year. Snow covers the ground about 80 days of the year.
About 168 frost-free days a year
In half of years the last 32° night comes by May 1 and the first one by October 18. That leaves about 168 frost-free days for gardens, shorter than 63% of U.S. towns.
Heating and cooling a home in Green Bay
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Green Bay, 96% of that work is heating and 4% is cooling, so the furnace matters far more than the air conditioner.
Degree days measure how far each day’s average temperature falls below or rises above 65°, added up over a year. Source: NOAA station normals.
Green Bay and its neighbors
Green Bay borders 4 towns with climate data. January nights across them vary by 2.1°. Luxemburg has both the coldest January nights (10°) and the hottest July afternoons (80°). Green Bay’s January low is 12° and its July high 78°.
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value.
How Green Bay compares
Compared with every U.S. town and city on TownTapestry, each counted once.
Warmer than it used to be
The last 30 years in Green Bay averaged 1.8° warmer than the 1900s. The biggest change is in December (+3.3°). The shift is larger than in 89% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Green Bay’s spot on NOAA’s grid
How much a month can swing
A normal is an average, and real years wander around it. March swings the most: between 1991 and 2020 its average temperature ranged from 21° to 45°. June is the most reliable, staying within 8°.
Common questions about Green Bay’s climate
What is the coldest month in Green Bay?
January, with a typical high of 26° and a low of 12°.
What is the hottest month in Green Bay?
July, with a typical high of 78° and a low of 60°. About 2 days a year reach 90°.
How much snow does Green Bay get?
About 48 inches in a normal winter, most of it in January.
When is the first frost in Green Bay?
In half of years the first 32° night comes by October 18, and the last spring frost by May 1.
What is the rainiest month in Green Bay?
June, with 4.0 inches of rain and melted snow. The year totals 33 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Green Bay itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Kewaunee, WI (17 mi) away. Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000.