Green Bay, WI Climate & Monthly Averages

Wisconsin, United States 🇺🇸 · humid continental climate
Annual avg
47°
Hottest month
July
Coldest month
January
Rainy days / yr
117
Sunshine
8.6 h/day
Right now: 80° and overcast - see live conditions

The climate of Green Bay

Located in Wisconsin, United States, Green Bay experiences a humid continental climate with warm summers and cold, often snowy winters. Afternoon temperatures peak near 82°F (28°C) in July and dip to about 27°F (-3°C) in January, with around 34.5 inches (877 mm) of precipitation falling across the year.

Climate quick facts

  • Hottest month: July - highs near 82°F (28°C)
  • Coldest month: January - highs near 27°F (-3°C)
  • Record high: 99°F (37°C) · Record low: -24°F (-31°C) (2015–2024)
  • Wettest month: July (11 rainy days) · Sunniest: July (12.7 h sun/day)
  • Climate type: humid continental - warm summers and cold, often snowy winters
  • Snow: about 23 days a year

Temperatures through the year

The warmest stretch of the year centers on July. Highs average 82°F (28°C) and overnight lows stay near 64°F (18°C). The coolest month is January, with typical highs of 27°F (-3°C) and lows around 14°F (-10°C). Based on 2015–2024 weather data, temperatures have reached as high as 99°F (37°C) and dropped as low as -24°F (-31°C).

Rain, sun and snow

July is usually the wettest month. It brings about 3.8 inches (97 mm) of rain over 11 days, while February is the driest. July brings the most sunshine, averaging 12.7 hours of sun a day. Snow falls on about 23 days in a typical year, mostly from November through April.

Monthly climate table

Monthly averages for Green Bay based on 2015–2024 weather data.
MonthHighLow Rain daysPrecipitation SunshineHumidity
January 27° 14° 7 1.5 in 5.2 h/day 76%
February 30° 13° 7 1.4 in 7.2 h/day 71%
March 42° 25° 10 2.6 in 8.1 h/day 67%
April 53° 35° 13 3.5 in 8.9 h/day 66%
May 67° 48° 11 3.7 in 10.6 h/day 65%
June 77° 59° 11 3.8 in 11.9 h/day 66%
July 82° 64° 11 3.8 in 12.7 h/day 68%
August 79° 63° 11 3.8 in 11.3 h/day 71%
September 73° 57° 9 2.8 in 9.7 h/day 73%
October 59° 44° 11 3.3 in 7.1 h/day 71%
November 45° 31° 7 2.1 in 6.1 h/day 70%
December 33° 21° 8 2.3 in 4.6 h/day 75%

Green Bay month by month

Green Bay weather in January

January brings highs around 27°F (-3°C), lows near 14°F (-10°C), about 7 wet days and roughly 5 snowy days - typically the coldest month of the year in Green Bay.

Green Bay weather in February

February brings highs around 30°F (-1°C), lows near 13°F (-11°C), about 7 wet days and roughly 4 snowy days - typically the driest month of the year in Green Bay.

Green Bay weather in March

March brings highs around 42°F (6°C), lows near 25°F (-4°C), about 10 wet days and roughly 4 snowy days.

Green Bay weather in April

April brings highs around 53°F (11°C), lows near 35°F (1°C), about 13 wet days and roughly 2 snowy days.

Green Bay weather in May

May brings highs around 67°F (19°C), lows near 48°F (9°C), about 11 wet days.

Green Bay weather in June

June brings highs around 77°F (25°C), lows near 59°F (15°C), about 11 wet days.

Green Bay weather in July

July brings highs around 82°F (28°C), lows near 64°F (18°C), about 11 wet days - typically the hottest month and the wettest month and the sunniest month of the year in Green Bay.

Green Bay weather in August

August brings highs around 79°F (26°C), lows near 63°F (17°C), about 11 wet days.

Green Bay weather in September

September brings highs around 73°F (23°C), lows near 57°F (14°C), about 9 wet days.

Green Bay weather in October

October brings highs around 59°F (15°C), lows near 44°F (7°C), about 11 wet days.

Green Bay weather in November

November brings highs around 45°F (7°C), lows near 31°F (0°C), about 7 wet days and roughly 2 snowy days.

Green Bay weather in December

December brings highs around 33°F (1°C), lows near 21°F (-6°C), about 8 wet days and roughly 5 snowy days.

Seasons in Green Bay

Spring (March through May)

Spring in Green Bay stays on the cool side of mild, with daytime highs averaging 54°F (12°C) and nights around 36°F (2°C); expect showers on roughly 34 days across the season, plus around 6 snowy days.

Summer (June through August)

Summer in Green Bay is pleasantly warm, with daytime highs averaging 79°F (26°C) and nights around 62°F (16°C); expect showers on roughly 34 days across the season.

Fall (September through November)

Fall in Green Bay is crisp but comfortable, with daytime highs averaging 59°F (15°C) and nights around 44°F (7°C); expect showers on roughly 27 days across the season, plus around 2 snowy days.

Winter (December through February)

Winter in Green Bay is frigid, with daytime highs averaging 30°F (-1°C) and nights around 16°F (-9°C); expect showers on roughly 23 days across the season, plus around 14 snowy days. Wind makes those temperatures feel harsher than they sound - pair the forecast winds with the wind speed converter to judge conditions on exposed skin.

Climate questions, answered

What is the average temperature in Green Bay?
The year-round mean is 47°F (8°C). Days typically reach 55°F (13°C) and nights settle near 39°F (4°C).
Is Green Bay hot in summer?
Warm to hot: July, the warmest month, averages highs of 82°F (28°C) - hot afternoons happen, but extremes are not the norm.
Is Green Bay cold in winter?
Winter here means deep cold - 14°F (-10°C) is just an average January night, and it has dropped to -24°F (-31°C).
How many rainy days does Green Bay get in a year?
About 117 days bring measurable precipitation, with July the wettest month and February the driest.

Best time to visit Green Bay

The best time to visit Green Bay is generally May to September, when this window offers the warmest, brightest days of the year. Daytime temperatures in that window typically sit near 76°F (24°C).

Pack for Green Bay with a heavy insulated coat, hat and gloves for winter; a compact umbrella or rain shell - showers are a regular feature. Evenings can feel noticeably cooler than afternoons - July nights average 64°F (18°C).

Green Bay temperature records (2015-2024)

Highest recorded
99°
in June
Lowest recorded
-24°
in January
Annual precipitation
34.5"
Snowy days / yr
23

Derived from ERA5 reanalysis data, 2015–2024. Official station records may differ.