Across the year, daylight in Ann Arbor ranges from about 8h 54m in December to 15h 6m in June — a 6h 12m swing that shapes sleep, mood and training rhythms. From roughly November through February, the sun sits too low for much vitamin D production.
Ann Arbor is part of the Southeast Michigan (Detroit & Ann Arbor); the nearest other Live10X guide is Detroit, about 36 miles away.
Ann Arbor by the numbers
- County
- Washtenaw County
- Climate
- Humid continental
- Elevation
- about 800 ft
- Latitude
- 42.3°N
- Shortest day
- 8h 54m
- Longest day
- 15h 6m
- Vitamin D winter
- November through February
- Metro
- Southeast Michigan
At a glance
Ann Arbor at a glance
- Top local priority in Ann Arbor: a winter movement plan.
- Daylight swings from about 8h 54m to 15h 6m across the year — anchor your wake time and get morning light.
- Sunlight is too weak for much vitamin D production from roughly November through February; a blood test shows where you stand.
- Use Nichols Arboretum and the Border-to-Border Trail for easy, regular outdoor movement.
Climate & lifestyle
What living in Ann Arbor means for your health
Ann Arbor has a humid continental climate — four distinct seasons, with warm to hot summers and cold winters that bring snow and short days. Seasonal shifts in light and temperature affect sleep, mood, activity and vitamin D, so a winter plan matters as much as a summer one.
- a winter movement plan
- morning light and vitamin D awareness
- winter light and vitamin D awareness
- consistent sleep through seasonal shifts
Light, sleep & vitamin D
Daylight in Ann Arbor across the year
8h 54m
Shortest day (December)
15h 6m
Longest day (June)
~4 mo
Low-UVB “vitamin D winter”
At about 42.3°N, Ann Arbor sees a 6h 12m swing in day length between the solstices. At this latitude, winter sunlight is too weak for meaningful vitamin D production for roughly four months. That's roughly November through February. Bright morning light helps anchor your body clock, and a simple blood test shows whether your vitamin D is where it should be.
Calculated from latitude using standard solar formulas and published latitude research. How we calculate this
Local wellness trends
Wellness trends in Ann Arbor
Winter wellness
Long winters in Ann Arbor have made indoor training, saunas and morning-light routines part of the local playbook.
Campus-driven fitness
A large student and faculty population keeps Ann Arbor's gyms, run clubs and rec fields busy, and campus events bring health research to the public.
Medical & research hub
Ann Arbor's major health systems mean strong access to preventive care, specialists and clinical research studies.
Riverfront greenways
Greenways and riverfront trails give Ann Arbor car-free corridors for walking, running and cycling.
Local health optimization resources
Places to move, recover and eat well in Ann Arbor
- GardenNichols ArboretumCalm, walkable green space — ideal for recovery days.
- Trailthe Border-to-Border TrailCar-free miles for zone 2 walks, runs and rides.
- ParkGallup ParkGreen space for walks, bodyweight workouts and time in nature.
Testing
At-home wellness genetic testing
Available throughout Ann Arbor: order online, collect a sample at home and review results with a qualified professional.
Learn more about at-home wellness genetic testingHealthcare
Preventive care & baseline labs
Primary care clinicians in Washtenaw County can order baseline labs — such as a lipid panel, HbA1c, vitamin D and B12 — useful context for any wellness plan.
Learn more about preventive care & baseline labsSeasonal playbook
A seasonal wellness playbook for Ann Arbor
- Winter: short days call for morning light, indoor strength and cardio plans, and a consistent wake time.
- Spring and fall: prime seasons for outdoor running, cycling and hiking.
- Summer: humid heat waves happen — hydrate well and train early on the hottest days.
- Winter light: with only about 8h 54m of daylight in December, get outside in the morning and keep indoor lighting bright during the day.
Recommended reading
The most relevant guides for Ann Arbor residents
FAQ
Ann Arbor wellness FAQs
Do I need to visit a clinic in Ann Arbor for a wellness genetic test?
How do you stay active through Ann Arbor's winters?
Can you get enough vitamin D from the sun in Ann Arbor?
How do seasonal daylight changes in Ann Arbor affect sleep?
What are good places to exercise outside in Ann Arbor?
How can Ann Arbor residents make the most of local healthcare for prevention?
The bottom line
Living well in Ann Arbor means working with its warm summers and cold, snowy winters: a winter movement plan, morning light and vitamin D awareness and winter light and vitamin D awareness. Add the fundamentals — consistent sleep, daily movement, strength training and a whole-food diet — and personalize with the wellness assessment and at-home testing.



