Willmar, Minnesota climate: Normal weather by month, frost dates and records
Willmar's normal year runs from 3°F January nights to 82°F July afternoons, with 28.7 inches of precipitation and 46 inches of snow a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 6.5°C, January lows of −16°C, July highs of 28°C, 728 mm of precipitation a year.
- NOAA stationWillmar Wastewater Treatment Plant
- Station IDUSC00219004
- Location45.11°N 95.04°W
- Elevation1,100 ft (335 m)
- From the center1 miles
- Population21,892
On October 22, the normal high in Willmar is 54°F and the normal low 34°F, and the chance of measurable rain or snow is 27%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Willmar.
- Jan 21° 3°
- Feb 26° 6°
- Mar 38° 20°
- Apr 54° 34°
- May 68° 47°
- Jun 78° 58°
- Jul 82° 62°
- Aug 79° 59°
- Sep 72° 50°
- Oct 57° 37°
- Nov 40° 24°
- Dec 26° 10°
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 Willmar each month?
July is the warmest month, with normal highs of 82°F; January the coldest, with normal lows of 3°F. The most precipitation falls in June (4.79 in), the least in February (0.67 in).
| Month | High | Low | Mean | Precip. | Snow | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|---|
| January | 21°F | 3°F | 11.7°F | 0.68 | 9.2 | 6 | <1 | 31 | 9 h 10 min |
| February | 26°F | 6°F | 15.8°F | 0.67 | 7.8 | 5 | <1 | 27 | 10 h 20 min |
| March | 38°F | 20°F | 29.1°F | 1.39 | 6.9 | 7 | <1 | 27 | 11 h 50 min |
| April | 54°F | 34°F | 43.8°F | 2.63 | 3.8 | 8 | <1 | 13 | 13 h 30 min |
| May | 68°F | 47°F | 57.4°F | 3.33 | 0.0 | 11 | 1 | 1 | 14 h 50 min |
| June | 78°F | 58°F | 67.9°F | 4.79 | 0.0 | 12 | 2 | <1 | 15 h 40 min |
| July | 82°F | 62°F | 71.7°F | 3.99 | 0.0 | 10 | 3 | <1 | 15 h 20 min |
| August | 79°F | 59°F | 69.1°F | 3.89 | 0.0 | 9 | 2 | <1 | 14 h 10 min |
| September | 72°F | 50°F | 61.1°F | 2.64 | 0.0 | 9 | 1 | 1 | 12 h 40 min |
| October | 57°F | 37°F | 46.9°F | 2.40 | 0.5 | 9 | <1 | 10 | 11 h |
| November | 40°F | 24°F | 31.8°F | 1.42 | 7.8 | 6 | <1 | 26 | 9 h 40 min |
| December | 26°F | 10°F | 18.3°F | 0.84 | 10.1 | 7 | <1 | 31 | 8 h 50 min |
| Year (annual) | 53°F | 34°F | 43.7°F | 28.67 | 46.1 | 98 | 8 | 166 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. | Snow |
|---|---|---|---|---|---|
| January | −6°C | −16°C | −11.3°C | 17 mm | 23 cm |
| February | −4°C | −14°C | −9.0°C | 17 mm | 20 cm |
| March | 3°C | −7°C | −1.6°C | 35 mm | 18 cm |
| April | 12°C | 1°C | 6.6°C | 67 mm | 10 cm |
| May | 20°C | 8°C | 14.1°C | 85 mm | 0 cm |
| June | 26°C | 14°C | 19.9°C | 122 mm | 0 cm |
| July | 28°C | 17°C | 22.1°C | 101 mm | 0 cm |
| August | 26°C | 15°C | 20.6°C | 99 mm | 0 cm |
| September | 22°C | 10°C | 16.2°C | 67 mm | 0 cm |
| October | 14°C | 3°C | 8.3°C | 61 mm | 1 cm |
| November | 5°C | −5°C | −0.1°C | 36 mm | 20 cm |
| December | −3°C | −12°C | −7.6°C | 21 mm | 26 cm |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00219004; 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 Willmar?
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 USC00219004.
When is the last frost in Willmar?
In Willmar, the last spring frost (32°F) comes after April 30 in half of years and after May 13 in one year in ten; the first autumn frost comes before October 7 in half of years and before September 23 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 13; 9 in 10 after April 16
- First autumn frost, half of years before
- October 71 year in 10 before September 23; 9 in 10 before October 21
NOAA puts the median frost-free season at 159 days, and the season without a hard freeze (28°F) at 179 days.
A hard freeze (28°F) comes after April 19 in half of springs and before October 19 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Willmar in zone 4b in ZIP code 56201. By the map's own method, the average of each year's coldest night over 1991-2020, Willmar's NOAA station is in zone 4b: the coldest night of a typical year reaches −21°F (17 complete years).
Frost dates for every NOAA station in Minnesota · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00219004; 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 Willmar?
In a normal year in Willmar, 8 days a year reach 90°F, 166 nights fall to 32°F or colder and 98 days bring measurable precipitation.
- Days at 90°F or more
- 8a normal year
- Days at 100°F or more
- fewer than 1a normal year
- Nights at 32°F or colder
- 166a normal year
- Days that stay below freezing
- 86high of 32°F or less
- Days with 0.01 inch of precipitation
- 98a normal year
- Days with 1 inch of snow or more
- 15a normal year
The highest temperature in this station's record (since 1893) is 107°F, on July 22, 1934; the lowest is −41°F, on January 9, 1977.
The wettest calendar year on that record is 1965, with 40.66 in; the snowiest season is 1950–51, with 103.7 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USC00219004; records: ACIS (NOAA Regional Climate Centers), station USC00219004. Records use complete months only; a month missing more than three days is left out.
How sunny is Willmar?
Over a year 74% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Willmar, 3.9 kWh per square metre a day. July is the sunniest month (82%) and December the cloudiest (61%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 75% | 1.8 |
| February | 81% | 3.0 |
| March | 72% | 3.8 |
| April | 70% | 4.8 |
| May | 69% | 5.5 |
| June | 74% | 6.1 |
| July | 82% | 6.5 |
| August | 80% | 5.4 |
| September | 76% | 4.1 |
| October | 69% | 2.6 |
| November | 67% | 1.7 |
| December | 61% | 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 Willmar need?
A normal year in Willmar brings 8,309 heating degree days, 55% more than the median U.S. place (5,373), and 596 cooling degree days, 34% 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 2,547 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,652 | 0 |
| February | 1,376 | 0 |
| March | 1,111 | 0 |
| April | 637 | 1 |
| May | 271 | 34 |
| June | 51 | 136 |
| July | 10 | 218 |
| August | 22 | 151 |
| September | 170 | 53 |
| October | 564 | 4 |
| November | 996 | 0 |
| December | 1,449 | 0 |
| Year (annual) | 8,309 | 596 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00219004. 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 Willmar's climate compare?
Willmar is warmer than 69 of the other 128 places with their own NOAA record in Minnesota, and wetter than 45. Across the 7,247 U.S. stations with normals, its annual mean of 43.7°F is warmer than 14%.
In the Köppen classification computed from these normals, Willmar is Dfa: continental, no dry season, hot 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 Willmar share this climate record?
6 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.
- Raymond, MN796 people · 12 mi SW
- Kerkhoven, MN783 people · 15 mi NW
- Kandiyohi, MN565 people · 5 mi E
- Prinsburg, MN511 people · 14 mi SW
- Pennock, MN480 people · 7 mi W
- Blomkest, MN140 people · 11 mi S
Source: Census Bureau 2024 Gazetteer (place centers) and Vintage 2024 population estimates. Distance and direction from the station to each place's center.
What do Willmar's other NOAA stations record?
One more NOAA station keeps 1991-2020 normals in or near Willmar. This page uses Willmar Wastewater Treatment Plant; the other differs by site and elevation:
| Station | From the center | Elevation | Year | Jan low | Jul high | Precip. | Snow | Last frost |
|---|---|---|---|---|---|---|---|---|
| Willmar (5 mi N) USC00219001 | 5 mi N | 1,190 ft | 42.9°F | 1°F | 81°F | 29.5 | – | May 1 |
Source: NOAA NCEI 1991-2020 normals for each station. Last frost: the median last spring date of 32°F.
Questions about Willmar's climate
What is the coldest month in Willmar?
January, with a normal high of 21°F and a normal low of 3°F. The warmest is July (82°F by day, 62°F at night).
Does it snow in Willmar?
Yes: 46 inches in a normal year, falling on 25 days with 0.1 inch or more, the most in December (10.1 inches).
What is the rainiest month in Willmar?
June, with 4.79 in of precipitation in a normal year; the driest is February with 0.67 in.
What plant hardiness zone is Willmar in?
The USDA's 2023 map puts Willmar in zone 4b in ZIP code 56201. By the same method at Willmar's NOAA station, the coldest night of a typical year reaches −21°F (17 years, 1991-2020): zone 4b.
How late can frost come in Willmar?
In half of years the last 32°F night comes after April 30; in one year in ten it comes after May 13. Waiting until May 13 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Minnesota climateThe statewide normals and every place in the state
- New London, MN14 miles from this station, 43.0°F a year
- Olivia, MN24 miles from this station, 43.1°F a year
- Litchfield, MN24 miles from this station, 42.2°F a year
- Benson, MN32 miles from this station, 43.7°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made