Corunna, Michigan climate: Normal weather by month, frost dates and records
Corunna's normal year runs from 15°F January nights to 83°F July afternoons, with 33.6 inches of precipitation a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 8.7°C, January lows of −9°C, July highs of 29°C, 853 mm of precipitation a year.
- NOAA stationCorunna (2 mi NE)
- Station IDUSC00201818
- Location43.00°N 84.07°W
- Elevation762 ft (232 m)
- Population3,014
On October 23, the normal high in Corunna is 58°F and the normal low 38°F, and the chance of measurable rain or snow is 37%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Corunna.
- Jan 31° 15°
- Feb 33° 16°
- Mar 45° 24°
- Apr 57° 33°
- May 70° 45°
- Jun 79° 55°
- Jul 83° 59°
- Aug 81° 57°
- Sep 75° 50°
- Oct 61° 40°
- Nov 48° 31°
- Dec 36° 22°
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 Corunna each month?
July is the warmest month, with normal highs of 83°F; January the coldest, with normal lows of 15°F. The most precipitation falls in May (3.95 in), the least in February (1.77 in).
| Month | High | Low | Mean | Precip. | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|
| January | 31°F | 15°F | 22.9°F | 2.17 | 14 | <1 | 29 | 9 h 20 min |
| February | 33°F | 16°F | 24.5°F | 1.77 | 11 | <1 | 27 | 10 h 30 min |
| March | 45°F | 24°F | 34.4°F | 2.12 | 10 | <1 | 26 | 11 h 50 min |
| April | 57°F | 33°F | 45.3°F | 3.51 | 12 | <1 | 16 | 13 h 20 min |
| May | 70°F | 45°F | 57.3°F | 3.95 | 13 | 1 | 2 | 14 h 40 min |
| June | 79°F | 55°F | 66.9°F | 3.22 | 11 | 3 | <1 | 15 h 20 min |
| July | 83°F | 59°F | 70.9°F | 3.33 | 10 | 5 | <1 | 15 h |
| August | 81°F | 57°F | 69.0°F | 3.19 | 10 | 2 | <1 | 14 h |
| September | 75°F | 50°F | 62.2°F | 2.80 | 9 | 1 | <1 | 12 h 30 min |
| October | 61°F | 40°F | 50.6°F | 3.01 | 12 | <1 | 7 | 11 h 10 min |
| November | 48°F | 31°F | 39.4°F | 2.55 | 11 | <1 | 20 | 9 h 50 min |
| December | 36°F | 22°F | 29.2°F | 1.98 | 13 | <1 | 27 | 9 h |
| Year (annual) | 58°F | 37°F | 47.7°F | 33.60 | 134 | 12 | 155 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. |
|---|---|---|---|---|
| January | −1°C | −9°C | −5.1°C | 55 mm |
| February | 1°C | −9°C | −4.2°C | 45 mm |
| March | 7°C | −4°C | 1.3°C | 54 mm |
| April | 14°C | 1°C | 7.4°C | 89 mm |
| May | 21°C | 7°C | 14.1°C | 100 mm |
| June | 26°C | 13°C | 19.4°C | 82 mm |
| July | 29°C | 15°C | 21.6°C | 85 mm |
| August | 27°C | 14°C | 20.6°C | 81 mm |
| September | 24°C | 10°C | 16.8°C | 71 mm |
| October | 16°C | 4°C | 10.3°C | 76 mm |
| November | 9°C | −1°C | 4.1°C | 65 mm |
| December | 2°C | −6°C | −1.6°C | 50 mm |
NOAA publishes no 1991-2020 snowfall normal for this station. The nearest record that keeps one, Owosso (5 miles away), gets 38 inches of snow in a normal year; elevation and distance can change that.
Source: NOAA NCEI 1991-2020 monthly normals, station USC00201818; 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 Corunna?
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 USC00201818.
When is the last frost in Corunna?
In Corunna, the last spring frost (32°F) comes after May 5 in half of years and after May 20 in one year in ten; the first autumn frost comes before October 14 in half of years and before September 29 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
- May 51 year in 10 after May 20; 9 in 10 after April 20
- First autumn frost, half of years before
- October 141 year in 10 before September 29; 9 in 10 before October 29
NOAA puts the median frost-free season at 160 days, and the season without a hard freeze (28°F) at 186 days.
A hard freeze (28°F) comes after April 24 in half of springs and before October 29 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Corunna in zone 6a in ZIP code 48867, the nearest ZIP area.
Frost dates for every NOAA station in Michigan · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00201818; USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026. 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 Corunna?
In a normal year in Corunna, 12 days a year reach 90°F, 155 nights fall to 32°F or colder and 134 days bring measurable precipitation.
- Days at 90°F or more
- 12a normal year
- Days at 100°F or more
- fewer than 1a normal year
- Nights at 32°F or colder
- 155a normal year
- Days that stay below freezing
- 52high of 32°F or less
- Days with 0.01 inch of precipitation
- 134a normal year
Source: NOAA NCEI 1991-2020 annual normals, station USC00201818.
How sunny is Corunna?
Over a year 71% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Corunna, 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 Corunna need?
A normal year in Corunna brings 6,822 heating degree days, 27% more than the median U.S. place (5,373), and 556 cooling degree days, 39% 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 2,579 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,305 | 0 |
| February | 1,135 | 0 |
| March | 949 | 2 |
| April | 594 | 2 |
| May | 268 | 31 |
| June | 57 | 112 |
| July | 13 | 196 |
| August | 23 | 147 |
| September | 142 | 58 |
| October | 454 | 8 |
| November | 770 | 0 |
| December | 1,111 | 0 |
| Year (annual) | 6,822 | 556 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00201818. 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.
How does Corunna's climate compare?
Corunna is warmer than 90 of the other 139 places with their own NOAA record in Michigan, and wetter than 52. Across the 7,247 U.S. stations with normals, its annual mean of 47.7°F is warmer than 31%.
In the Köppen classification computed from these normals, Corunna 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 Corunna share this climate record?
New Lothrop has no NOAA station with 1991-2020 normals of its 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.
- New Lothrop, MI581 people · 10 mi NE
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 Corunna's climate
What is the coldest month in Corunna?
January, with a normal high of 31°F and a normal low of 15°F. The warmest is July (83°F by day, 59°F at night).
Does it snow in Corunna?
Yes. NOAA publishes no 1991-2020 snowfall normal for Corunna's NOAA station; the nearest record that keeps one, Owosso (5 miles away), records 38 inches of snow in a normal year.
What is the rainiest month in Corunna?
May, with 3.95 in of precipitation in a normal year; the driest is February with 1.77 in.
What plant hardiness zone is Corunna in?
The USDA's 2023 map puts Corunna in zone 6a in ZIP code 48867, the nearest ZIP area.
How late can frost come in Corunna?
In half of years the last 32°F night comes after May 5; in one year in ten it comes after May 20. Waiting until May 20 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Michigan climateThe statewide normals and every place in the state
- Owosso, MI6 miles from this station, 47.6°F a year
- Durand, MI7 miles from this station, 47.7°F a year
- Flint, MI17 miles from this station, 47.7°F a year
- Linden, MI19 miles from this station, 46.8°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made