Chelsea, Michigan climate: Normal weather by month, frost dates and records
Chelsea's normal year runs from 16°F January nights to 82°F July afternoons, with 34.7 inches of precipitation and 33 inches of snow a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 9.1°C, January lows of −9°C, July highs of 28°C, 881 mm of precipitation a year.
- NOAA stationChelsea
- Station IDUSC00201502
- Location42.33°N 84.01°W
- Elevation900 ft (274 m)
- From the center1 miles
- Population5,393
On October 23, the normal high in Chelsea is 58°F and the normal low 38°F, and the chance of measurable rain or snow is 35%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Chelsea.
- Jan 31° 16°
- Feb 34° 17°
- Mar 44° 25°
- Apr 58° 37°
- May 70° 48°
- Jun 79° 57°
- Jul 82° 61°
- Aug 80° 59°
- Sep 74° 51°
- Oct 61° 40°
- Nov 47° 31°
- Dec 36° 23°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
What is the weather like in Chelsea each month?
July is the warmest month, with normal highs of 82°F; January the coldest, with normal lows of 16°F. The most precipitation falls in May (3.83 in), the least in February (1.98 in).
| Month | High | Low | Mean | Precip. | Snow | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|---|
| January | 31°F | 16°F | 23.5°F | 2.41 | 10.9 | 13 | <1 | 29 | 9 h 20 min |
| February | 34°F | 17°F | 25.7°F | 1.98 | 8.6 | 10 | <1 | 26 | 10 h 30 min |
| March | 44°F | 25°F | 34.9°F | 2.24 | 4.7 | 9 | <1 | 23 | 11 h 50 min |
| April | 58°F | 37°F | 47.1°F | 3.01 | 0.9 | 11 | <1 | 11 | 13 h 20 min |
| May | 70°F | 48°F | 58.6°F | 3.83 | 0.0 | 12 | <1 | 1 | 14 h 30 min |
| June | 79°F | 57°F | 67.7°F | 3.64 | 0.0 | 10 | 3 | <1 | 15 h 20 min |
| July | 82°F | 61°F | 71.4°F | 3.45 | 0.0 | 9 | 5 | <1 | 15 h |
| August | 80°F | 59°F | 69.6°F | 3.56 | 0.0 | 9 | 2 | <1 | 14 h |
| September | 74°F | 51°F | 62.5°F | 2.74 | 0.0 | 9 | 1 | <1 | 12 h 30 min |
| October | 61°F | 40°F | 50.6°F | 3.14 | 0.0 | 11 | <1 | 6 | 11 h 10 min |
| November | 47°F | 31°F | 39.0°F | 2.61 | 1.8 | 10 | <1 | 18 | 9 h 50 min |
| December | 36°F | 23°F | 29.3°F | 2.08 | 6.0 | 11 | <1 | 27 | 9 h 10 min |
| Year (annual) | 58°F | 39°F | 48.3°F | 34.69 | 32.9 | 123 | 11 | 141 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. | Snow |
|---|---|---|---|---|---|
| January | −1°C | −9°C | −4.7°C | 61 mm | 28 cm |
| February | 1°C | −8°C | −3.5°C | 50 mm | 22 cm |
| March | 7°C | −4°C | 1.6°C | 57 mm | 12 cm |
| April | 14°C | 3°C | 8.4°C | 76 mm | 2 cm |
| May | 21°C | 9°C | 14.8°C | 97 mm | 0 cm |
| June | 26°C | 14°C | 19.8°C | 92 mm | 0 cm |
| July | 28°C | 16°C | 21.9°C | 88 mm | 0 cm |
| August | 27°C | 15°C | 20.9°C | 90 mm | 0 cm |
| September | 23°C | 11°C | 16.9°C | 70 mm | 0 cm |
| October | 16°C | 5°C | 10.3°C | 80 mm | 0 cm |
| November | 8°C | −1°C | 3.9°C | 66 mm | 5 cm |
| December | 2°C | −5°C | −1.5°C | 53 mm | 15 cm |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00201502; 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.
When is the best weather to visit Chelsea?
Normal highs sit between 65°F and 85°F in May, June, July, August and September. Of those, September has the fewest days with rain (9).
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 USC00201502.
When is the last frost in Chelsea?
In Chelsea, the last spring frost (32°F) comes after April 30 in half of years and after May 17 in one year in ten; the first autumn frost comes before October 12 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
- April 301 year in 10 after May 17; 9 in 10 after April 18
- First autumn frost, half of years before
- October 121 year in 10 before September 28; 9 in 10 before October 27
NOAA puts the median frost-free season at 163 days, and the season without a hard freeze (28°F) at 187 days.
A hard freeze (28°F) comes after April 20 in half of springs and before October 26 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Chelsea in zone 6a in ZIP code 48118, the nearest ZIP area. By the map's own method, the average of each year's coldest night over 1991-2020, Chelsea's NOAA station is in zone 6a: the coldest night of a typical year reaches −10°F (16 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 USC00201502; 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 in Chelsea?
In a normal year in Chelsea, 11 days a year reach 90°F, 141 nights fall to 32°F or colder and 123 days bring measurable precipitation.
- Days at 90°F or more
- 11a normal year
- Days at 100°F or more
- fewer than 1a normal year
- Nights at 32°F or colder
- 141a normal year
- Days that stay below freezing
- 51high of 32°F or less
- Days with 0.01 inch of precipitation
- 123a normal year
- Days with 1 inch of snow or more
- 13a normal year
Source: NOAA NCEI 1991-2020 annual normals, station USC00201502.
How sunny is Chelsea?
Over a year 71% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Chelsea, 3.8 kWh per square metre a day. July is the sunniest month (80%) and December the cloudiest (52%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 56% | 1.5 |
| February | 62% | 2.4 |
| March | 67% | 3.6 |
| April | 68% | 4.6 |
| May | 70% | 5.4 |
| June | 76% | 6.2 |
| July | 80% | 6.3 |
| August | 78% | 5.4 |
| September | 77% | 4.3 |
| October | 67% | 2.7 |
| November | 62% | 1.8 |
| December | 52% | 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 much heating and cooling does Chelsea need?
A normal year in Chelsea brings 6,655 heating degree days, 24% more than the median U.S. place (5,373), and 610 cooling degree days, 33% 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 2,705 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,286 | 0 |
| February | 1,100 | 0 |
| March | 935 | 1 |
| April | 543 | 5 |
| May | 236 | 36 |
| June | 47 | 127 |
| July | 12 | 211 |
| August | 19 | 164 |
| September | 134 | 60 |
| October | 453 | 7 |
| November | 780 | 0 |
| December | 1,108 | 0 |
| Year (annual) | 6,655 | 610 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00201502. 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.
Has Chelsea been warmer than normal lately?
2025 averaged 49.2°F, 0.9°F above the 1991-2020 normal of 48.3°F. 5 of the 5 complete years since 2021 ran warmer than the normal.
| Year | Mean | Against normal | Precip. | Snow |
|---|---|---|---|---|
| 2021 | 50.4°F | +2.1°F | 37.29 | 34.4 |
| 2022 | 48.7°F | +0.4°F | 26.24 | 35.4 |
| 2023 | 50.5°F | +2.3°F | 34.22 | 26.4 |
| 2024 | 52.1°F | +3.8°F | 39.41 | 27.1 |
| 2025 | 49.2°F | +0.9°F | 30.62 | 33.0 |
Source: observed years: ACIS, station USC00201502. A year counts only with all twelve months complete.
How does Chelsea's climate compare?
Chelsea is warmer than 106 of the other 139 places with their own NOAA record in Michigan, and wetter than 75. Across the 7,247 U.S. stations with normals, its annual mean of 48.3°F is warmer than 33%.
In the Köppen classification computed from these normals, Chelsea 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 Chelsea share this climate record?
2 places have no NOAA station with 1991-2020 normals of their 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.
- Dexter, MI4,528 people · 7 mi E
- Grass Lake, MI1,101 people · 11 mi SW
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 Chelsea's climate
What is the coldest month in Chelsea?
January, with a normal high of 31°F and a normal low of 16°F. The warmest is July (82°F by day, 61°F at night).
Does it snow in Chelsea?
Yes: 33 inches in a normal year, falling on 22 days with 0.1 inch or more, the most in January (10.9 inches).
What is the rainiest month in Chelsea?
May, with 3.83 in of precipitation in a normal year; the driest is February with 1.98 in.
What plant hardiness zone is Chelsea in?
The USDA's 2023 map puts Chelsea in zone 6a in ZIP code 48118, the nearest ZIP area. By the same method at Chelsea's NOAA station, the coldest night of a typical year reaches −10°F (16 years, 1991-2020): zone 6a.
How late can frost come in Chelsea?
In half of years the last 32°F night comes after April 30; in one year in ten it comes after May 17. Waiting until May 17 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Michigan climateThe statewide normals and every place in the state
- Hell, MI7 miles from this station, 47.9°F a year
- Manchester, MI12 miles from this station, 48.3°F a year
- Whitmore Lake, MI14 miles from this station, 47.1°F a year
- Ann Arbor, MI16 miles from this station, 47.8°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made