South Lyon, Michigan Weather
Day 93 of summer. Read today’s microseason across nine climate regions →
South Lyon weather forecast — hour by hour, 7-day outlook, NOAA radar
Conditions updated 10:54 AM EDT · Open-Meteo
- TodaySep 21Overcast——64°50°—
- TuesdaySep 22Overcast——64°46°0°
- WednesdaySep 23Rain28%0.27″66°53°+2°
- ThursdaySep 24Overcast——69°51°+3°
- FridaySep 25Overcast——70°51°+1°
- SaturdaySep 26Overcast——72°49°+2°
- SundaySep 27Light Drizzle—0.01″61°56°-11°
Air quality now AQI 46 · Good
AQI 46 (Good), driven by PM2.5. AQI flat over the last 6 hours (within ±3 points). PM2.5 at 7.4 µg/m³, PM10 at 7.7 µg/m³ — typical background levels with no transport signature.
OK No precautions needed for the general population; unusually sensitive individuals may consider limiting prolonged outdoor exertion.
What's driving it
PM × Wind × Precip
PM2.5 at 7.4 µg/m³, PM10 at 7.7 µg/m³ — typical background levels with no transport signature.
- PM2.5/PM10
- 0.96
- Wind
- breezy
- Recent rain
- 0h in last 6h
- Pattern
- background
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).
September dries up ditches or breaks down bridges.
- Moonrise
- 5:14 PM
- Moonset
- 1:46 AM
- In sign
- ♑︎ Capricorn
South Lyon at a glance
- Today vs. normal: Today averages 57°F (high 64°F, low 50°F), 4°F below the 61°F normal for Sep 21
- Last frost: May 5 (1991–2020 median, NOAA station 11 km away)
- Microseason: Sep 21–25
- Planting calendar: September — plant garlic (overwinter); harvest tomatoes, peppers, beans, summer squash, winter squash
16-Day Forecast — South Lyon
- Mon62°52°2%
- Tue64°46°3%
- Wed66°53°21%
- Thu69°51°3%
- Fri70°51°1%
- Sat72°49°0%
- Sun61°56°2%
- Mon73°57°5%
- Tue82°56°18%
- Wed74°56°21%
- Thu68°50°21%
- Fri61°44°11%
- Sat80°55°25%
- Sun66°51°12%
- Mon55°41°23%
- Tue55°36°19%
Forecast data from Open-Meteo (CC BY 4.0).
Live wind & temperature near South Lyon
Interactive wind and temperature map centered on South Lyon — it loads in your browser. Open the full weather map.
Right now in the garden
Fall planting + final harvests
As of September 21, the season's first frost (typically October 13) is approaching. Pick what frost-tender plants still carry before the next cold front. This city's planting calendar for September: plant garlic (overwinter); harvest tomatoes, peppers, beans, summer squash, and winter squash.
Sun & seasons in South Lyon
South Lyon sits in Oakland County, where the year’s longest day runs 15h 18m of daylight and its shortest just 9h 4m — a swing of +6h 14m between the June and December solstices. Clocks spring forward on Sunday, March 8, 2026 and fall back on Sunday, November 1, 2026.
Detroit, the state’s largest city, lies about 29 miles to the E. The nearest town South Lyon tracks is Ann Arbor, roughly 13 miles to the SSW.
Air quality in South Lyon
Air quality in South Lyon’s county has trended dirtier since 2020; its cleanest year on record was 2020 (median AQI 37). See the full air-quality history for South Lyon.
Planting calendar
| Month | Plant | Harvest |
|---|---|---|
| April | lettuce, peas, spinach, radishes | — |
| May | lettuce, peas, spinach, radishes, tomatoes, peppers, beans, squash | lettuce, spinach, radishes |
| June | tomatoes, peppers, beans, squash | lettuce, peas, spinach, radishes |
| July | tomatoes, peppers, beans, squash, fall brassicas, carrots | lettuce, peas, spinach, beans, summer squash, garlic |
| August | — | peas, tomatoes, peppers, beans, summer squash, garlic |
| September | garlic (overwinter) | tomatoes, peppers, beans, summer squash, winter squash |
| October | — | tomatoes, peppers, beans, summer squash, winter squash, fall brassicas, carrots |
| November | — | fall brassicas, carrots |
A year in weather
South Lyon's warmest month is July (~72°F mean) and its coldest is January (~24°F). Rainfall peaks in June (3.9 inches) and bottoms out in February (2.5 inches).
| Month | Mean temp | Precip | Rainy days |
|---|---|---|---|
| January | 24° | 3.0″ | 18 |
| February | 27° | 2.5″ | 14 |
| March | 36° | 2.8″ | 14 |
| April | 48° | 3.4″ | 14 |
| May | 59° | 3.8″ | 15 |
| June | 68° | 3.9″ | 12 |
| July | 72° | 3.5″ | 12 |
| August | 70° | 3.5″ | 11 |
| September | 63° | 3.2″ | 11 |
| October | 51° | 3.0″ | 13 |
| November | 39° | 2.8″ | 14 |
| December | 29° | 2.8″ | 17 |
Regional context
Similar climates Whitmore Lake, MI, Wixom, MI, Brighton, MI
South Lyon's climate, from NOAA NCEI 1991-2020 station normals, pairs 24°F Januarys with 72°F Julys — a 48°F swing. About 38.3 inches of precipitation falls over roughly 166 days a year.
South Lyon's precipitation spreads evenly across the seasons: June peaks at 3.9 inches on 12.4 wet days, while February holds 2.5 inches over 14.4 — no season dominates South Lyon's rain calendar. That lines South Lyon up with places like Whitmore Lake, MI, Wixom, MI and Brighton, MI, fed by overlapping storm tracks.
By May 5 the frosts ease in South Lyon, opening the season for kale, peas, spinach, and parsnips. In South Lyon, warm-season transplants — tomatoes, peppers, basil — wait two weeks past South Lyon's frost date. South Lyon's window closes around October 13 as South Lyon's overnight lows return below freezing. In about half of years, South Lyon's last freeze comes after May 5.
Similar climates: Whitmore Lake, MI, Wixom, MI, Brighton, MI, Novi, MI, Northville, MI.
Frequently asked
- When does it freeze in South Lyon?
- In South Lyon, expect the last spring frost near May 5; South Lyon's first autumn frost comes around October 13.
- What is the rainy season in South Lyon?
- June is the wettest month in South Lyon, about 3.9 inches on average; the year totals roughly 38 inches.
- What is the warmest month in South Lyon?
- South Lyon peaks in July, when the mean runs near 72°F.
- What is the coldest month in South Lyon?
- January is South Lyon's coldest month, averaging about 24°F.
- When can I start a vegetable garden in South Lyon?
- Around May 5, start frost-hardy crops in South Lyon; tomatoes and basil belong a fortnight later.
- How many rainy days does South Lyon get?
- South Lyon averages about 166 days with measurable rain or snow each year.
- What hardiness zone is South Lyon?
- Because South Lyon bottoms near 24°F in January, that winter low sets South Lyon's USDA zone — verify by ZIP.
- What is the 10-day forecast for South Lyon?
- South Lyon's extended outlook — daily high and low temperatures and precipitation chances for each upcoming day — is in the daily forecast above.
- Will it rain this week in South Lyon?
- See this week's day-by-day rain chances for South Lyon in the daily forecast above, and the next 24 hours in the hourly chart.
- What is the weather like right now in South Lyon?
- Current conditions for South Lyon and the next 24 hours — temperature, precipitation chance, and wind by the hour — are in the hourly forecast chart above.
- How often is the South Lyon forecast updated?
- The South Lyon forecast on this page is built from Open-Meteo weather-model data and refreshes regularly through the day.
- When are sunrise and sunset in South Lyon?
- Today's sunrise and sunset times for South Lyon are in the Almanac section above, along with civil dawn, civil dusk, and day length. Day length is longest near the summer solstice and shortest near the winter solstice.
- How accurate is the weather forecast for South Lyon?
- The next few days in South Lyon's forecast are the most reliable; accuracy declines beyond about a week as weather-model uncertainty grows.
South Lyon sits at 42.5°N; its climate zone is warm-summer humid continental (Köppen approximation).
ZIP codes in South Lyon
- 48178