Grand Marais, Minnesota climate: Normal weather by month, frost dates and records
Grand Marais's normal year runs from 7°F January nights to 70°F August afternoons, with 25.9 inches of precipitation a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 4.2°C, January lows of −14°C, August highs of 21°C, 658 mm of precipitation a year.
- NOAA stationGrand Marais
- Station IDUSW00094992
- Location47.75°N 90.34°W
- Elevation610 ft (186 m)
- Population1,306
On October 22, the normal high in Grand Marais is 49°F and the normal low 35°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 Grand Marais.
- Jan 24° 7°
- Feb 27° 10°
- Mar 35° 20°
- Apr 45° 30°
- May 55° 38°
- Jun 62° 44°
- Jul 70° 51°
- Aug 70° 54°
- Sep 63° 48°
- Oct 52° 38°
- Nov 39° 26°
- Dec 29° 14°
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 70°F; January the coldest, with normal lows of 7°F. The most precipitation falls in June (3.73 in), the least in January (0.81 in).
| Month | High | Low | Mean | Precip. | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|
| January | 24°F | 7°F | 15.4°F | 0.81 | 10 | <1 | 30 | 8 h 50 min |
| February | 27°F | 10°F | 18.1°F | 0.88 | 8 | <1 | 28 | 10 h 10 min |
| March | 35°F | 20°F | 27.2°F | 1.22 | 9 | <1 | 28 | 11 h 50 min |
| April | 45°F | 30°F | 37.4°F | 2.24 | 10 | <1 | 20 | 13 h 30 min |
| May | 55°F | 38°F | 46.5°F | 2.50 | 13 | <1 | 5 | 15 h 10 min |
| June | 62°F | 44°F | 52.9°F | 3.73 | 14 | <1 | <1 | 16 h |
| July | 70°F | 51°F | 60.4°F | 3.10 | 12 | <1 | <1 | 15 h 40 min |
| August | 70°F | 54°F | 61.9°F | 2.40 | 11 | <1 | <1 | 14 h 20 min |
| September | 63°F | 48°F | 55.5°F | 2.65 | 11 | <1 | <1 | 12 h 40 min |
| October | 52°F | 38°F | 44.6°F | 2.98 | 12 | <1 | 8 | 11 h |
| November | 39°F | 26°F | 32.7°F | 1.93 | 10 | <1 | 21 | 9 h 20 min |
| December | 29°F | 14°F | 21.6°F | 1.48 | 11 | <1 | 29 | 8 h 30 min |
| Year (annual) | 48°F | 32°F | 39.5°F | 25.92 | 130 | <1 | 170 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. |
|---|---|---|---|---|
| January | −4°C | −14°C | −9.2°C | 21 mm |
| February | −3°C | −12°C | −7.7°C | 22 mm |
| March | 2°C | −7°C | −2.7°C | 31 mm |
| April | 7°C | −1°C | 3.0°C | 57 mm |
| May | 13°C | 3°C | 8.1°C | 64 mm |
| June | 17°C | 7°C | 11.6°C | 95 mm |
| July | 21°C | 11°C | 15.8°C | 79 mm |
| August | 21°C | 12°C | 16.6°C | 61 mm |
| September | 17°C | 9°C | 13.1°C | 67 mm |
| October | 11°C | 3°C | 7.0°C | 76 mm |
| November | 4°C | −3°C | 0.4°C | 49 mm |
| December | −2°C | −10°C | −5.8°C | 38 mm |
NOAA publishes no 1991-2020 snowfall normal for this station. Grand Marais's own co-op station Grand Marais station does: 51 inches of snow in a normal year (see the other stations below).
Source: NOAA NCEI 1991-2020 monthly normals, station USW00094992; 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 July and August. Of those, August has the fewest days with rain (11).
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 USW00094992.
When is the last frost in Grand Marais?
In Grand Marais, the last spring frost (32°F) comes after May 22 in half of years and after June 18 in one year in ten; the first autumn frost comes before October 9 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 221 year in 10 after June 18; 9 in 10 after May 3
- First autumn frost, half of years before
- October 91 year in 10 before September 25; 9 in 10 before October 25
NOAA puts the median frost-free season at 136 days, and the season without a hard freeze (28°F) at 167 days.
A hard freeze (28°F) comes after May 4 in half of springs and before October 24 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Grand Marais in zone 3b in ZIP code 55612, the nearest ZIP area. By the map's own method, the average of each year's coldest night over 1991-2020, Grand Marais's NOAA station is in zone 5a: the coldest night of a typical year reaches −18°F (19 complete years); the map interpolates between stations and terrain, so the station and the ZIP area can differ by half a zone.
Frost dates for every NOAA station in Minnesota · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USW00094992; 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 Grand Marais?
In a normal year in Grand Marais, a 90°F day is rare, 170 nights fall to 32°F or colder and 130 days bring measurable precipitation.
- Days at 90°F or more
- fewer than 1a normal year
- Days at 100°F or more
- fewer than 1a normal year
- Nights at 32°F or colder
- 170a normal year
- Days that stay below freezing
- 80high of 32°F or less
- Days with 0.01 inch of precipitation
- 130a normal year
Source: NOAA NCEI 1991-2020 annual normals, station USW00094992.
How sunny is Grand Marais?
Over a year 69% 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 (78%) and December the cloudiest (55%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 58% | 1.2 |
| February | 63% | 2.1 |
| March | 66% | 3.3 |
| April | 69% | 4.6 |
| May | 69% | 5.4 |
| June | 71% | 5.9 |
| July | 78% | 6.1 |
| August | 77% | 5.1 |
| September | 72% | 3.7 |
| October | 63% | 2.3 |
| November | 57% | 1.3 |
| December | 55% | 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 9,310 heating degree days, 73% more than the median U.S. place (5,373), and 51 cooling degree days, 94% fewer than the median (908). Nine months need 300 or more heating degree days, a monthly mean of about 55°F or colder. For gardens and crops, NOAA counts 1,045 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,538 | 0 |
| February | 1,315 | 0 |
| March | 1,172 | 0 |
| April | 828 | 0 |
| May | 575 | 0 |
| June | 364 | 1 |
| July | 167 | 23 |
| August | 117 | 22 |
| September | 289 | 4 |
| October | 632 | 0 |
| November | 968 | 0 |
| December | 1,345 | 0 |
| Year (annual) | 9,310 | 51 |
Source: NOAA NCEI 1991-2020 monthly normals, station USW00094992. 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 Grand Marais been warmer than normal lately?
2023 averaged 41.3°F, 1.8°F above the 1991-2020 normal of 39.5°F. 2 of the 2 complete years since 2021 ran warmer than the normal.
| Year | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 42.4°F | +2.9°F | 21.14 |
| 2023 | 41.3°F | +1.8°F | 22.37 |
Source: observed years: ACIS, station USW00094992. A year counts only with all twelve months complete.
How does Grand Marais's climate compare?
Grand Marais is warmer than 20 of the other 128 places with their own NOAA record in Minnesota, and wetter than 17. Across the 7,247 U.S. stations with normals, its annual mean of 39.5°F is warmer than 5%.
In the Köppen classification computed from these normals, Grand Marais 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.
What do Grand Marais's other NOAA stations record?
One more NOAA station keeps 1991-2020 normals in or near Grand Marais. This page uses Grand Marais; the other differs by site and elevation:
| Station | From this station | Elevation | Year | Jan low | Jul high | Precip. | Snow | Last frost |
|---|---|---|---|---|---|---|---|---|
| Grand Marais station USC00213282 | 1 mi NE | 612 ft | 38.3°F | 6°F | 69°F | 25.8 | 51 | May 20 |
Source: NOAA NCEI 1991-2020 normals for each station. Last frost: the median last spring date of 32°F.
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 7°F. The warmest is August (70°F by day, 54°F at night).
Does it snow in Grand Marais?
Yes. NOAA publishes no 1991-2020 snowfall normal for Grand Marais's NOAA station; Grand Marais's own co-op station Grand Marais station records 51 inches of snow in a normal year.
What is the rainiest month in Grand Marais?
June, with 3.73 in of precipitation in a normal year; the driest is January with 0.81 in.
What plant hardiness zone is Grand Marais in?
The USDA's 2023 map puts Grand Marais in zone 3b in ZIP code 55612, the nearest ZIP area. By the same method at Grand Marais's NOAA station, the coldest night of a typical year reaches −18°F (19 years, 1991-2020): zone 5a.
How late can frost come in Grand Marais?
In half of years the last 32°F night comes after May 22; in one year in ten it comes after June 18. Waiting until June 18 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Minnesota climateThe statewide normals and every place in the state
- Lutsen, MN16 miles from this station, 36.7°F a year
- Grand Portage, MN34 miles from this station, 38.1°F a year
- Gunflint Lake (10 mi NW), MN38 miles from this station, 36.7°F a year
- Wolf Ridge Environmental Learning Center, MN45 miles from this station, 38.9°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made