Ann Arbor, Michigan Weather
Fireflies rise from the lawn. Day 77 of spring. Read this microseason across nine climate regions →
Ann Arbor weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJun 4Overcast——85°52°—
- FridayJun 5Rain36%0.20″83°63°-2°
- SaturdayJun 6Light Showers78%—78°67°-5°
- SundayJun 7Overcast——79°60°+1°
- MondayJun 8Overcast——74°57°-5°
- TuesdayJun 9Overcast29%—80°60°+6°
- WednesdayJun 10Overcast27%—80°64°0°
Ozone at AQI 104. AQI flat over the last 6 hours (within ±3 points). Overcast through the UV peak window (cloud cover ~68%) — afternoon ozone should stay flat.
CAUTION Sensitive groups (children, elderly, respiratory conditions) should limit prolonged outdoor exertion.
What's driving it
Ozone × UV × Sky
Ozone at AQI 104. Overcast through the UV peak window (cloud cover ~68%) — afternoon ozone should stay flat.
- Present
- AQI 104
- UV peak
- 7.5 at 1 PM
- Sky at peak
- overcast
- Projected peak
- AQI 52
Trends
Seven days of AQI and PM2.5.
Hourly air-quality data from the Copernicus Atmosphere Monitoring Service, charted across the past and next several days. Dashed lines mark the AQI breakpoints at 50 (Good → Moderate) and 100 (Moderate → Unhealthy for Sensitive Groups).
A summer fog for fair, a winter fog for rain.
- Moonrise
- 4:11 AM
- Moonset
- 1:28 PM
- In sign
- ♒︎ Aquarius
Fireflies rise from the lawn
Ann Arbor at a glance
- Today vs. normal: 9°F above the seasonal normal for this latitude
- Last frost: April 30 (climatological average for this latitude)
- Microseason: Jun 1–5
- Planting window: Harvest spring lettuce before it bolts. Sow heat-tolerant greens.
Right now in the garden
Peak growing season
As of June 4, the growing season is at its peak — frost is months away. Continue succession-planting beans and summer squash. Start fall brassicas (broccoli, cabbage, kale) from seed indoors for transplanting in late summer.
SPC Convective Outlook
Storm Prediction Center — Ann Arbor
SPC has placed Ann Arbor in the Marginal Risk category for severe thunderstorms day after tomorrow.
- TODAYNONENo severe risk
- TOMORROWTSTMGeneral Thunderstorms
- DAY 3MRGLMarginal Risk
Isolated severe storms possible. Limited threat for hail or damaging wind.
Source: NOAA / NWS Storm Prediction Center categorical convective outlook. Outlooks are re-issued multiple times per day; this page reflects the most recent SPC polygons covering the city’s coordinates.
Planting calendar
| Month | Plant | Harvest |
|---|---|---|
| January | — | — |
| February | — | — |
| March | — | — |
| April | — | — |
| May | lettuce, peas, spinach, radishes | lettuce, peas, radishes |
| June | lettuce, peas, spinach, radishes, tomatoes, peppers, beans, squash | lettuce, peas, radishes |
| July | tomatoes, peppers, beans, squash | tomatoes, beans, summer squash |
| August | tomatoes, peppers, beans, squash, fall brassicas, garlic (overwinter), carrots | tomatoes, beans, summer squash |
| September | fall brassicas, garlic (overwinter), carrots | tomatoes, beans, summer squash |
| October | — | winter squash, tomatoes (last) |
| November | — | — |
| December | — | — |
A year in weather
July stands as Ann Arbor's warmest month with average temperatures around 72°F, while January marks the coldest period at roughly 24°F. The wettest conditions occur in June with 4.3 inches of rainfall, compared to February's drier 2.4 inches.
| Month | Mean temp | Precip | Rainy days |
|---|---|---|---|
| January | 24° | 2.8″ | 8 |
| February | 26° | 2.4″ | 6 |
| March | 35° | 2.8″ | 6 |
| April | 46° | 3.3″ | 7 |
| May | 58° | 3.8″ | 8 |
| June | 68° | 4.3″ | 7 |
| July | 72° | 3.9″ | 7 |
| August | 70° | 3.3″ | 6 |
| September | 62° | 3.0″ | 6 |
| October | 51° | 2.9″ | 7 |
| November | 39° | 2.7″ | 7 |
| December | 29° | 2.6″ | 7 |
Regional context
Ann Arbor falls within the warm-summer humid continental climate classification, sharing temperature patterns, seasonal rhythms, and growing conditions with other cities in this regional climate zone.
Similar climates: Detroit, MI, Grand Rapids, MI, Lansing, MI, Flint, MI, Kalamazoo, MI.
Naturalist notes
Late May brings the emergence of wild columbine blooms throughout local woodlands, their distinctive spurred flowers appearing as soil temperatures stabilize after the final frost.
American robins begin their second nesting cycle in early June, with pairs selecting fresh sites in maples and oaks as daylight stretches past 15 hours.
Frequently asked
- When does it freeze in Ann Arbor?
- Spring's final frost in Ann Arbor generally occurs around mid-May, while the first autumn frost typically arrives in mid-October.
- What is the rainy season in Ann Arbor?
- June records the highest monthly rainfall at approximately 4.3 inches, contributing to the city's annual total of roughly 38 inches.
- What is the warmest month in Ann Arbor?
- July typically delivers the year's warmest temperatures, averaging around 72°F.
- What is the coldest month in Ann Arbor?
- January brings the coldest conditions, with average temperatures near 24°F.
- When can I start a vegetable garden in Ann Arbor?
- Cool-season vegetables like peas and lettuce can be planted around the last spring frost in mid-May, while warm-season crops such as tomatoes and peppers should wait an additional 1–2 weeks.
- How many rainy days does Ann Arbor get?
- Ann Arbor experiences precipitation on approximately 82 days each year.
- What hardiness zone is Ann Arbor?
- Ann Arbor's USDA hardiness zone reflects its average minimum winter temperatures; the USDA's online tool can provide the current zone designation using the city's ZIP code.
Climate
Ann Arbor, Michigan experiences a warm-summer humid continental climate. Winter temperatures in January typically hover around 24°F, while July brings average highs of 72°F, creating a 48°F seasonal temperature range.
Throughout the year, the city receives approximately 38 inches of precipitation distributed across roughly 82 rainy days.
Local weather patterns respond to Ann Arbor's latitude at 42.3°N, the influence of nearby large water bodies, and regional elevation changes. These factors determine growing seasons, frost timing, and daily weather variations.