Your nature year
Ann Arbor, Michiganthrough the year
When do frost, green-up and fall color come to Ann Arbor?
For a day trip, Ottawa Refuge is 53 miles off; its spring migration is late April to mid-May (local timing). For fall foliage, the nearest is Cuyahoga Valley (133 mi, usually Oct 15–21).
At some 888 feet up, Ann Arbor is on low ground. Frost usually lets go around May 5 and comes back around Oct 10, according to the nearest NOAA station, Ann Arbor SE: roughly 158 days without it. Spring takes about 4 weeks to go from leaf to bloom. The USA-NPN spring index puts first leaf here around Apr 9 and first bloom around May 8. Head southeast for the closest of the 3 places we follow around Ann Arbor.
Updated Sep 27. Sources: US Census Bureau, 2024 Gazetteer (places) ↗ (opens in a new tab), US Census Bureau, city and town population estimates, 2024 ↗ (opens in a new tab), NOAA NCEI U.S. Climate Normals 1991–2020 (annual/seasonal) ↗ (opens in a new tab)
Ann Arbor's year at a glance
- Frost possible
- Frost-free, ~May 5 to ~Oct 10
- First leaf ~Apr 9
- First bloom ~May 8
- Today
Near Ann Arbor right now
- First fall frost usually around Oct 10 · last spring frost around May 5NOAA 1991–2020 normals, Ann Arbor SE (3.1 mi, 50% dates)~11 days
- Fall foliage · Cuyahoga Valley · 133 miusually Oct 15–21~2 weeks
Ann Arbor's nature year
- Wildflowers · Cuyahoga ValleyMar–May
- Spring migration · Ottawa RefugeApr–May
- Apr: Spring green-upApr
- May: Last spring frostMay
- Oct: First fall frostOct
- Oct: Fall foliage · Cuyahoga ValleyOct
Nearby, season by season
Fall foliage
- Cuyahoga Valley · 133 miusually Oct 15–21~2 weeks
- Au Sable River · 150 miLocal timing: Oct 1–31~2 days
Spring migration
- Ottawa Refuge · 53 miLocal timing: late April to mid-May~7 months
Wildflowers
- Cuyahoga Valley · 133 miLocal timing: Mar 21–May 15~6 months
Snow in Ann Arbor
Snow usually becomes possible around Nov 9 (our calculation from NOAA's daily snow chances: the first day the chance of 0.1" or more of snow reaches 10%). NOAA's normals at Ann Arbor SE (3.1 mi away): 59 inches of snow in an average year, about 18.5 days with 1 inch or more.
NOAA's chance of at least 0.1 inch of snow on each date (one value per week, September to May), averaged over 1991–2020. A typical year, not a forecast.
Frost and green-up
Last spring frost
May 5
Average (50% date)
First fall frost
Oct 10
About 158 days without frost between
Spring green-up
Apr 9
First bloom around May 8
Frost: NOAA 1991–2020 climate normals at Ann Arbor SE (3.1 mi from Ann Arbor), the day a 32 °F night is as likely as not. Green-up: the USA-NPN Spring Index, 1991–2020 average at the town.
Questions people ask
When is the first frost in Ann Arbor?
On average around Oct 10, and the last spring frost around May 5: about 158 days without frost between. These are NOAA's 1991–2020 normals at Ann Arbor SE, 3.1 miles away (the day a 32 °F night is as likely as not).
When does spring green-up reach Ann Arbor?
The USA-NPN Spring Index puts first leaf around Apr 9 and first bloom around May 8, on average for 1991–2020 at the town.
Where can I see fall foliage near Ann Arbor?
Cuyahoga Valley, 133 miles (usually Oct 15–21); Au Sable River, 150 miles (local timing: Oct 1–31). Distances are straight-line.
Where can I see spring migration near Ann Arbor?
Ottawa Refuge, 53 miles (local timing: late April to mid-May). Distances are straight-line.
When does it start snowing in Ann Arbor?
Snow usually becomes possible around Nov 9: our calculation from NOAA's daily snow chances: the first day the chance of 0.1" or more of snow reaches 10%, at Ann Arbor SE. An average year brings 59 inches (NOAA 1991–2020). A typical year, not a forecast.Sources: NOAA NCEI U.S. Climate Normals 1991–2020 (annual/seasonal snowfall) ↗ (opens in a new tab), NOAA NCEI U.S. Climate Normals 1991–2020 (daily snowfall probabilities) ↗ (opens in a new tab)
How we know
US Census Bureau, 2024 Gazetteer (places) (opens in a new tab) (Sep 27) · US Census Bureau, city and town population estimates, 2024 (opens in a new tab) (Sep 27) · NOAA NCEI U.S. Climate Normals 1991–2020 (annual/seasonal) (opens in a new tab) (Sep 27) · USA National Phenology Network, Spring Index 1991–2020 averages (opens in a new tab) (Sep 27)