Ann Arbor SE, Michigan climate: Climate normals at a NOAA weather station
Ann Arbor SE's normal year runs from 16°F January nights to 84°F July afternoons, with 37.9 inches of precipitation and 59 inches of snow a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 9.0°C, January lows of −9°C, July highs of 29°C, 962 mm of precipitation a year.
- NOAA stationAnn Arbor SE
- Station IDUSC00200228
- Location42.24°N 83.69°W
- Elevation832 ft (254 m)
On October 23, the normal high in Ann Arbor SE is 59°F and the normal low 37°F, and the chance of measurable rain or snow is 43%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Ann Arbor SE.
- Jan 32° 16°
- Feb 35° 16°
- Mar 45° 25°
- Apr 58° 34°
- May 70° 46°
- Jun 80° 56°
- Jul 84° 59°
- Aug 82° 58°
- Sep 75° 50°
- Oct 62° 39°
- Nov 48° 30°
- Dec 36° 22°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
What is the weather like at Ann Arbor SE each month?
July is the warmest month, with normal highs of 84°F; January the coldest, with normal lows of 16°F. The most precipitation falls in June (4.25 in), the least in February (2.42 in).
| Month | High | Low | Mean | Precip. | Snow | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|---|
| January | 32°F | 16°F | 24.0°F | 2.84 | 16.6 | 18 | <1 | 29 | 9 h 20 min |
| February | 35°F | 16°F | 25.5°F | 2.42 | 17.1 | 15 | <1 | 27 | 10 h 30 min |
| March | 45°F | 25°F | 35.0°F | 2.76 | 7.3 | 14 | <1 | 25 | 11 h 50 min |
| April | 58°F | 34°F | 46.2°F | 3.34 | 2.4 | 14 | <1 | 13 | 13 h 20 min |
| May | 70°F | 46°F | 57.9°F | 3.79 | 0.0 | 15 | 1 | 2 | 14 h 30 min |
| June | 80°F | 56°F | 67.6°F | 4.25 | 0.0 | 12 | 3 | <1 | 15 h 10 min |
| July | 84°F | 59°F | 71.5°F | 3.85 | 0.0 | 11 | 6 | <1 | 15 h |
| August | 82°F | 58°F | 69.7°F | 3.34 | 0.0 | 11 | 3 | <1 | 14 h |
| September | 75°F | 50°F | 62.4°F | 2.98 | 0.0 | 11 | 2 | <1 | 12 h 30 min |
| October | 62°F | 39°F | 50.5°F | 2.93 | 0.1 | 14 | <1 | 7 | 11 h 10 min |
| November | 48°F | 30°F | 38.8°F | 2.73 | 3.9 | 12 | <1 | 19 | 9 h 50 min |
| December | 36°F | 22°F | 29.2°F | 2.64 | 11.9 | 17 | <1 | 27 | 9 h 10 min |
| Year (annual) | 59°F | 38°F | 48.2°F | 37.87 | 59.3 | 163 | 14 | 147 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. | Snow |
|---|---|---|---|---|---|
| January | 0°C | −9°C | −4.4°C | 72 mm | 42 cm |
| February | 2°C | −9°C | −3.6°C | 61 mm | 43 cm |
| March | 7°C | −4°C | 1.7°C | 70 mm | 19 cm |
| April | 15°C | 1°C | 7.9°C | 85 mm | 6 cm |
| May | 21°C | 8°C | 14.4°C | 96 mm | 0 cm |
| June | 27°C | 13°C | 19.8°C | 108 mm | 0 cm |
| July | 29°C | 15°C | 21.9°C | 98 mm | 0 cm |
| August | 28°C | 14°C | 20.9°C | 85 mm | 0 cm |
| September | 24°C | 10°C | 16.9°C | 76 mm | 0 cm |
| October | 17°C | 4°C | 10.3°C | 74 mm | 0 cm |
| November | 9°C | −1°C | 3.8°C | 69 mm | 10 cm |
| December | 2°C | −5°C | −1.6°C | 67 mm | 30 cm |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00200228; annual normals. Wet days: 0.01 inch or more; 90°F days and freezing nights: NOAA's day counts. Daylight: sunrise to sunset on the 15th, computed from the latitude.
Which months are mildest at Ann Arbor SE?
Normal highs sit between 65°F and 85°F in May, June, July, August and September. Of those, August has the fewest days with rain (11).
That is a measurement, not a recommendation: it counts the months whose normal afternoon high sits between 65°F and 85°F, where a light layer is enough by day.
Source: NOAA NCEI 1991-2020 monthly normals, station USC00200228.
When is the last frost at Ann Arbor SE?
In Ann Arbor SE, the last spring frost (32°F) comes after May 5 in half of years and after May 20 in one year in ten; the first autumn frost comes before October 10 in half of years and before September 28 in one year in ten.
Frost-free in half of yearsFrost in 1 to 9 years out of 10Frost most years
- Last spring frost, half of years after
- May 51 year in 10 after May 20; 9 in 10 after April 21
- First autumn frost, half of years before
- October 101 year in 10 before September 28; 9 in 10 before October 24
NOAA puts the median frost-free season at 157 days, and the season without a hard freeze (28°F) at 180 days.
A hard freeze (28°F) comes after April 24 in half of springs and before October 23 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Ann Arbor SE in zone 6a in ZIP code 48104, the nearest ZIP area. By the map's own method, the average of each year's coldest night over 1991-2020, the station is in zone 6a: the coldest night of a typical year reaches −7°F (17 complete years).
Frost dates for every NOAA station in Michigan · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00200228; USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026; the station zone: ACIS daily lows, 1991-2020. A 10% date means one year in ten has a frost after it in spring or before it in autumn.
How hot and how cold does it get at Ann Arbor SE?
In a normal year in Ann Arbor SE, 14 days a year reach 90°F, 147 nights fall to 32°F or colder and 163 days bring measurable precipitation.
- Days at 90°F or more
- 14a normal year
- Days at 100°F or more
- fewer than 1a normal year
- Nights at 32°F or colder
- 147a normal year
- Days that stay below freezing
- 46high of 32°F or less
- Days with 0.01 inch of precipitation
- 163a normal year
- Days with 1 inch of snow or more
- 19a normal year
The highest temperature in this station's record (since 2003) is 100°F, on July 18, 2012; the lowest is −18°F, on January 31, 2019.
The wettest calendar year on that record is 2011, with 51.16 in; the snowiest season is 2007–08, with 83.8 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USC00200228; records: ACIS (NOAA Regional Climate Centers), station USC00200228. Records use complete months only; a month missing more than three days is left out.
How sunny is it at Ann Arbor SE?
Over a year 71% of the sunlight that would reach the ground under clear skies gets through the clouds at Ann Arbor SE, 3.8 kWh per square metre a day. July is the sunniest month (80%) and December the cloudiest (54%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 59% | 1.6 |
| February | 62% | 2.4 |
| March | 66% | 3.5 |
| April | 68% | 4.7 |
| May | 70% | 5.5 |
| June | 76% | 6.2 |
| July | 80% | 6.2 |
| August | 78% | 5.3 |
| September | 77% | 4.3 |
| October | 68% | 2.8 |
| November | 63% | 1.8 |
| December | 54% | 1.2 |
Source: NASA POWER solar climatology, 2001-2020 (CERES SYN1deg). Satellite-based, for the 1-degree cell (about 100 km across) around the station, so it describes the area rather than the airport.
How many heating and cooling degree days does Ann Arbor SE record?
A normal year at Ann Arbor SE brings 6,680 heating degree days, 24% more than the median U.S. place (5,373), and 594 cooling degree days, 35% fewer than the median (908). Seven months need 300 or more heating degree days, a monthly mean of about 55°F or colder. For gardens and crops, NOAA counts 2,659 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,271 | 0 |
| February | 1,104 | 0 |
| March | 931 | 1 |
| April | 565 | 1 |
| May | 249 | 30 |
| June | 47 | 125 |
| July | 10 | 211 |
| August | 18 | 164 |
| September | 134 | 56 |
| October | 455 | 6 |
| November | 786 | 0 |
| December | 1,110 | 0 |
| Year (annual) | 6,680 | 594 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00200228. A degree day is one degree of a day's mean temperature below 65°F (heating) or above it (cooling); utilities use them to estimate energy use.
Have recent years at Ann Arbor SE been warmer than normal?
2025 averaged 48.8°F, 0.6°F above the 1991-2020 normal of 48.2°F. 5 of the 5 complete years since 2021 ran warmer than the normal.
| Year | Mean | Against normal | Precip. | Snow |
|---|---|---|---|---|
| 2021 | 50.1°F | +1.9°F | 45.49 | 51.7 |
| 2022 | 48.4°F | +0.2°F | 31.04 | 49.6 |
| 2023 | 50.3°F | +2.1°F | 39.13 | 42.9 |
| 2024 | 51.8°F | +3.5°F | 40.51 | 38.2 |
| 2025 | 48.8°F | +0.6°F | 32.28 | 45.3 |
Source: observed years: ACIS, station USC00200228. A year counts only with all twelve months complete.
How does Ann Arbor SE's climate compare?
Ann Arbor SE is warmer than 105 of the 140 places with their own NOAA record in Michigan, and wetter than 107. Across the 7,247 U.S. stations with normals, its annual mean of 48.2°F is warmer than 33%.
In the Köppen classification computed from these normals, Ann Arbor SE is Dfb: continental, no dry season, warm summer. What the classes mean.
Places with the most similar year elsewhere
Measured month by month on the normal high, low and precipitation, among places of 20,000 or more people in other states:
Source: NOAA NCEI 1991-2020 normals for every station PlainClimate covers. Similarity: the root-mean-square difference of the 36 monthly figures, precipitation weighted so an inch counts like 6°F.
Which places near Ann Arbor SE share this climate record?
Ypsilanti has no NOAA station with 1991-2020 normals of its own, and this station is the nearest full record. A place's own climate can differ from these figures, by several degrees where it sits much higher or lower than the station, nearer the coast, or inside a large city's heat; for the larger places the next nearest records are named with their yearly mean, so the spread around them is visible, and places of 50,000 or more have their own page with NOAA's gridded normals.
- Ypsilanti, MI20,150 people · 4 mi E
Source: Census Bureau 2024 Gazetteer (place centers) and Vintage 2024 population estimates. Distance and direction from the station to each place's center.
Questions about Ann Arbor SE's climate
What is the coldest month at Ann Arbor SE?
January, with a normal high of 32°F and a normal low of 16°F. The warmest is July (84°F by day, 59°F at night).
Does it snow at Ann Arbor SE?
Yes: 59 inches in a normal year, falling on 55 days with 0.1 inch or more, the most in February (17.1 inches).
What is the rainiest month at Ann Arbor SE?
June, with 4.25 in of precipitation in a normal year; the driest is February with 2.42 in.
What plant hardiness zone is Ann Arbor SE in?
The USDA's 2023 map puts Ann Arbor SE in zone 6a in ZIP code 48104, the nearest ZIP area. By the same method at the station, the coldest night of a typical year reaches −7°F (17 years, 1991-2020): zone 6a.
How late can frost come at Ann Arbor SE?
In half of years the last 32°F night comes after May 5; in one year in ten it comes after May 20. Waiting until May 20 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Michigan climateThe statewide normals and every place in the state
- Ann Arbor, MI3 miles from this station, 47.8°F a year
- Ann Arbor University of Michigan, MI4 miles from this station, 48.8°F a year
- Saline, MI7 miles from this station, 48.2°F a year
- Milan, MI11 miles from this station, 49.2°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made