Grand Marais, Michigan climate: Normal weather by month, frost dates and records
Grand Marais's normal year runs from 14°F January nights to 75°F August afternoons. (NOAA 1991-2020 normals)
In metric: a yearly mean of 5.9°C, January lows of −10°C, August highs of 24°C.
- NOAA stationGrand Marais (2 mi E)
- Station IDUSW00014859
- Location46.67°N 85.95°W
- Elevation624 ft (190 m)
- Population (census place)255
On October 23, the normal high in Grand Marais is 51°F and the normal low 37°F.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Grand Marais.
- Jan 24° 14°
- Feb 27° 13°
- Mar 37° 20°
- Apr 48° 28°
- May 61° 40°
- Jun 70° 48°
- Jul 75° 55°
- Aug 75° 56°
- Sep 68° 50°
- Oct 55° 39°
- Nov 41° 29°
- Dec 31° 20°
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 Grand Marais each month?
August is the warmest month, with normal highs of 75°F; January the coldest, with normal lows of 14°F.
| Month | High | Low | Mean | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|
| January | 24°F | 14°F | 18.9°F | – | <1 | 31 | 9 h |
| February | 27°F | 13°F | 20.1°F | – | <1 | 28 | 10 h 20 min |
| March | 37°F | 20°F | 28.2°F | – | <1 | 29 | 11 h 50 min |
| April | 48°F | 28°F | 37.9°F | – | <1 | 24 | 13 h 30 min |
| May | 61°F | 40°F | 50.3°F | – | <1 | 10 | 15 h |
| June | 70°F | 48°F | 59.1°F | – | 2 | 2 | 15 h 50 min |
| July | 75°F | 55°F | 64.5°F | – | 2 | <1 | 15 h 30 min |
| August | 75°F | 56°F | 65.4°F | – | 1 | <1 | 14 h 20 min |
| September | 68°F | 50°F | 59.1°F | – | <1 | 1 | 12 h 40 min |
| October | 55°F | 39°F | 47.0°F | – | <1 | 10 | 11 h |
| November | 41°F | 29°F | 34.9°F | – | <1 | 24 | 9 h 30 min |
| December | 31°F | 20°F | 25.2°F | – | <1 | 31 | 8 h 40 min |
| Year (annual) | 51°F | 34°F | 42.6°F | – | 5 | 191 |
The same normals in °C and millimetres
| Month | High | Low | Mean |
|---|---|---|---|
| January | −4°C | −10°C | −7.3°C |
| February | −3°C | −10°C | −6.6°C |
| March | 3°C | −7°C | −2.1°C |
| April | 9°C | −2°C | 3.3°C |
| May | 16°C | 4°C | 10.2°C |
| June | 21°C | 9°C | 15.1°C |
| July | 24°C | 13°C | 18.1°C |
| August | 24°C | 13°C | 18.6°C |
| September | 20°C | 10°C | 15.1°C |
| October | 13°C | 4°C | 8.3°C |
| November | 5°C | −2°C | 1.6°C |
| December | −1°C | −7°C | −3.8°C |
NOAA publishes no 1991-2020 snowfall normal for this station, and no record within 25 miles keeps one, so snow is left out here rather than estimated.
Source: NOAA NCEI 1991-2020 monthly normals, station USW00014859; 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 Grand Marais?
Normal highs sit between 65°F and 85°F in June, July, August and September.
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 USW00014859.
When is the last frost in Grand Marais?
In Grand Marais, the last spring frost (32°F) comes after May 27 in half of years and after June 13 in one year in ten; the first autumn frost comes before October 10 in half of years and before September 25 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 271 year in 10 after June 13; 9 in 10 after May 7
- First autumn frost, half of years before
- October 101 year in 10 before September 25; 9 in 10 before October 27
NOAA puts the median frost-free season at 138 days, and the season without a hard freeze (28°F) at 168 days.
A hard freeze (28°F) comes after May 9 in half of springs and before October 25 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Grand Marais in zone 5b in ZIP code 49839, 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 USW00014859; 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 Grand Marais?
In a normal year in Grand Marais, 5 days a year reach 90°F and 191 nights fall to 32°F or colder.
- Days at 90°F or more
- 5a normal year
- Days at 100°F or more
- fewer than 1a normal year
- Nights at 32°F or colder
- 191a normal year
- Days that stay below freezing
- 69high of 32°F or less
The highest temperature in this station's record (since 1900) is 99°F, on July 29, 1988; the lowest is −32°F, on March 5, 1917.
The wettest calendar year on that record is 1949, with 43.08 in; the snowiest season is 1976–77, with 282.3 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USW00014859; records: ACIS (NOAA Regional Climate Centers), station USW00014859. Records use complete months only; a month missing more than three days is left out.
How sunny is Grand Marais?
Over a year 68% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Grand Marais, 3.5 kWh per square metre a day. July is the sunniest month (77%) and December the cloudiest (49%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 51% | 1.1 |
| February | 58% | 2.0 |
| March | 62% | 3.2 |
| April | 66% | 4.4 |
| May | 70% | 5.5 |
| June | 73% | 6.0 |
| July | 77% | 6.0 |
| August | 75% | 5.1 |
| September | 71% | 3.8 |
| October | 60% | 2.2 |
| November | 52% | 1.2 |
| December | 49% | 0.9 |
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 Grand Marais need?
A normal year in Grand Marais brings 8,394 heating degree days, 56% more than the median U.S. place (5,373), and 247 cooling degree days, 73% fewer than the median (908). Eight months need 300 or more heating degree days, a monthly mean of about 55°F or colder. For gardens and crops, NOAA counts 1,703 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,427 | 0 |
| February | 1,259 | 0 |
| March | 1,142 | 0 |
| April | 812 | 0 |
| May | 466 | 10 |
| June | 218 | 41 |
| July | 97 | 83 |
| August | 71 | 82 |
| September | 207 | 30 |
| October | 561 | 1 |
| November | 903 | 0 |
| December | 1,232 | 0 |
| Year (annual) | 8,394 | 247 |
Source: NOAA NCEI 1991-2020 monthly normals, station USW00014859. 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 Grand Marais's climate compare?
Grand Marais is warmer than 19 of the other 139 places with their own NOAA record in Michigan. Across the 7,247 U.S. stations with normals, its annual mean of 42.6°F is warmer than 11%.
Source: NOAA NCEI 1991-2020 normals for every station PlainClimate covers.
Questions about Grand Marais's climate
What is the coldest month in Grand Marais?
January, with a normal high of 24°F and a normal low of 14°F. The warmest is August (75°F by day, 56°F at night).
What plant hardiness zone is Grand Marais in?
The USDA's 2023 map puts Grand Marais in zone 5b in ZIP code 49839, the nearest ZIP area.
How late can frost come in Grand Marais?
In half of years the last 32°F night comes after May 27; in one year in ten it comes after June 13. Waiting until June 13 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Michigan climateThe statewide normals and every place in the state
- Newberry, MI32 miles from this station, 41.9°F a year
- Tahquamenon Falls State Park, MI35 miles from this station, 39.7°F a year
- Munsing Lakeshore, MI37 miles from this station, 42.3°F a year
- Munising, MI38 miles from this station, 40.9°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made