Ann Arbor, MI Climate & Monthly Averages
The climate of Ann Arbor
A 26°C spread between its warmest and coolest months puts Ann Arbor among the more strongly seasonal places we cover. July averages 82°F (28°C) by day; January averages 32°F (0°C), with nights at 19°F (-7°C).
Climate quick facts
- Hottest month: July - highs near 82°F (28°C)
- Coldest month: January - highs near 32°F (0°C)
- Decade extremes (2015-2024): 94°F (34°C) high · -25°F (-32°C) low
- Wettest month: July (12 rainy days) · Sunniest: July (12.2 h sun/day)
- Climate type: humid continental
- Annual swing: 26°C between the average warmest and coolest month · day to night: 9°C
- Snow: about 19 days a year
- Months with freezing average lows: 4
- Average humidity: 71%
Temperatures through the year
July is the warm end of the year, averaging 82°F (28°C) by day and 64°F (18°C) overnight. January bottoms out at 32°F (0°C) in daylight, 19°F (-7°C) after dark. The gridded 2015-2024 daily record for this location tops out at 94°F (34°C) and bottoms at -25°F (-32°C) - decade extremes, not all-time station records. The wettest month is July (3.6 inches (91 mm) across 12 days) and the driest November.
Rain, sun and snow
July is the brightest month at 12.2 hours of sun a day, against an annual average of 8.2 - duller than about 78% of the cities we track. Between the average July and the average January lie 26°C, a wider spread than roughly 88% of the cities we track.
How Ann Arbor compares
- 29% of the year's precipitation falls in its wettest three months - more evenly spread than all but 9% of the 3496 cities we track.
- Ann Arbor averages 50°F (10°C) across the year - cooler than all but 11% of the 3496 cities we track.
Ranked against every city in our dataset, each measured on the same ten-year window.
Monthly climate table
| Month | High | Low | Rain days | Precipitation | Sunshine | Humidity |
|---|---|---|---|---|---|---|
| January | 32° | 19° | 10 | 2.5 in | 4.4 h/day | 75% |
| February | 36° | 19° | 9 | 2.5 in | 6.5 h/day | 73% |
| March | 46° | 28° | 10 | 3.2 in | 7.5 h/day | 67% |
| April | 56° | 37° | 13 | 3.4 in | 8.6 h/day | 67% |
| May | 69° | 50° | 12 | 3.6 in | 10.1 h/day | 68% |
| June | 78° | 59° | 12 | 3.5 in | 12.0 h/day | 66% |
| July | 82° | 64° | 12 | 3.6 in | 12.2 h/day | 70% |
| August | 80° | 63° | 11 | 3.5 in | 11.2 h/day | 72% |
| September | 74° | 58° | 9 | 2.9 in | 9.4 h/day | 74% |
| October | 61° | 46° | 11 | 3.4 in | 7.1 h/day | 73% |
| November | 47° | 34° | 9 | 2.3 in | 5.8 h/day | 73% |
| December | 39° | 27° | 10 | 2.5 in | 4.1 h/day | 77% |
Ann Arbor month by month
Ann Arbor weather in January
January brings highs around 32°F (0°C), lows near 19°F (-7°C), about 10 wet days and roughly 5 snowy days - typically the coldest month of the year in Ann Arbor.
Ann Arbor weather in February
February brings highs around 36°F (2°C), lows near 19°F (-7°C), about 9 wet days and roughly 4 snowy days.
Ann Arbor weather in March
March brings highs around 46°F (8°C), lows near 28°F (-2°C), about 10 wet days and roughly 3 snowy days.
Ann Arbor weather in April
April brings highs around 56°F (14°C), lows near 37°F (3°C), about 13 wet days and roughly 2 snowy days.
Ann Arbor weather in May
May brings highs around 69°F (21°C), lows near 50°F (10°C), about 12 wet days.
Ann Arbor weather in June
June brings highs around 78°F (26°C), lows near 59°F (15°C), about 12 wet days.
Ann Arbor weather in July
July brings highs around 82°F (28°C), lows near 64°F (18°C), about 12 wet days - typically the hottest month and the wettest month and the sunniest month of the year in Ann Arbor.
Ann Arbor weather in August
August brings highs around 80°F (27°C), lows near 63°F (17°C), about 11 wet days.
Ann Arbor weather in September
September brings highs around 74°F (24°C), lows near 58°F (14°C), about 9 wet days.
Ann Arbor weather in October
October brings highs around 61°F (16°C), lows near 46°F (8°C), about 11 wet days.
Ann Arbor weather in November
November brings highs around 47°F (9°C), lows near 34°F (1°C), about 9 wet days and roughly 2 snowy days - typically the driest month of the year in Ann Arbor.
Ann Arbor weather in December
December brings highs around 39°F (4°C), lows near 27°F (-3°C), about 10 wet days and roughly 3 snowy days.
Seasons in Ann Arbor
Spring (March through May)
Spring in Ann Arbor is mild, with daytime highs averaging 57°F (14°C) and nights around 38°F (4°C); rain falls on around 36 of the 90 days, plus about 5 snowy days.
Summer (June through August)
Summer in Ann Arbor settles into easy warmth, with daytime highs averaging 80°F (27°C) and nights around 62°F (17°C); rain falls on around 34 of the 90 days. Daylight is generous - around 11.8 hours of sun a day.
Fall (September through November)
Fall in Ann Arbor is crisp but comfortable, with daytime highs averaging 61°F (16°C) and nights around 46°F (8°C); expect showers on roughly 30 days across the season, plus about 2 snowy days.
Winter (December through February)
Winter in Ann Arbor is frigid, with daytime highs averaging 36°F (2°C) and nights around 22°F (-6°C); expect showers on roughly 30 days across the season, plus about 12 snowy days. Wind sharpens cold like this considerably; pair the forecast winds with the wind speed converter to judge exposed conditions.
Climate questions, answered
How warm is Ann Arbor on average?
What should I pack for Ann Arbor?
How much sun does Ann Arbor get?
How cold does Ann Arbor get in winter?
How humid does Ann Arbor get?
How many rainy days does Ann Arbor get in a year?
Best time to visit Ann Arbor
June to October is the sweet spot for Ann Arbor - these are the warmest and brightest weeks of the year. Expect 75°F (24°C) in the afternoon and around 11 days of rain in a typical month of it. For the same question asked the other way round, see where else is warm in June.
Pack for Ann Arbor with light clothing for the warm months, a heavy insulated coat, hat and gloves for winter and a compact umbrella or rain shell. July nights average 64°F (18°C), so evenings rarely match the afternoons.
Ann Arbor temperature records (2015-2024)
Derived from ERA5 reanalysis data, 2015–2024. Official station records may differ.