Spirit Lake, Iowa climate: Normal weather by month, frost dates and records
Spirit Lake's normal year runs from 7°F January nights to 83°F July afternoons, with 29.1 inches of precipitation and 42 inches of snow a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 7.6°C, January lows of −14°C, July highs of 28°C, 738 mm of precipitation a year.
- NOAA stationSpirit Lake
- Station IDUSC00137859
- Location43.42°N 95.14°W
- Elevation1,420 ft (433 m)
- From the center1 miles
- Population5,548
On October 23, the normal high in Spirit Lake is 55°F and the normal low 35°F, and the chance of measurable rain or snow is 18%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Spirit Lake.
- Jan 24° 7°
- Feb 28° 11°
- Mar 42° 23°
- Apr 56° 35°
- May 68° 48°
- Jun 79° 59°
- Jul 83° 63°
- Aug 80° 60°
- Sep 73° 52°
- Oct 59° 39°
- Nov 42° 25°
- Dec 29° 13°
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 Spirit Lake each month?
July is the warmest month, with normal highs of 83°F; January the coldest, with normal lows of 7°F. The most precipitation falls in June (4.77 in), the least in January (0.55 in).
| Month | High | Low | Mean | Precip. | Snow | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|---|
| January | 24°F | 7°F | 15.6°F | 0.55 | 9.5 | 5 | <1 | 31 | 9 h 20 min |
| February | 28°F | 11°F | 19.6°F | 0.63 | 8.2 | 5 | <1 | 27 | 10 h 30 min |
| March | 42°F | 23°F | 32.4°F | 1.43 | 6.0 | 6 | <1 | 24 | 11 h 50 min |
| April | 56°F | 35°F | 45.5°F | 2.99 | 5.1 | 9 | <1 | 10 | 13 h 20 min |
| May | 68°F | 48°F | 57.9°F | 4.13 | 0.1 | 10 | 1 | 1 | 14 h 40 min |
| June | 79°F | 59°F | 68.7°F | 4.77 | 0.0 | 9 | 2 | <1 | 15 h 20 min |
| July | 83°F | 63°F | 72.7°F | 3.53 | 0.0 | 7 | 5 | <1 | 15 h 10 min |
| August | 80°F | 60°F | 70.1°F | 3.69 | 0.0 | 8 | 2 | <1 | 14 h |
| September | 73°F | 52°F | 62.6°F | 3.03 | 0.0 | 6 | 1 | <1 | 12 h 30 min |
| October | 59°F | 39°F | 48.8°F | 2.09 | 0.4 | 7 | <1 | 7 | 11 h 10 min |
| November | 42°F | 25°F | 33.6°F | 1.39 | 4.2 | 4 | <1 | 20 | 9 h 40 min |
| December | 29°F | 13°F | 20.8°F | 0.82 | 8.0 | 5 | <1 | 30 | 9 h |
| Year (annual) | 55°F | 36°F | 45.7°F | 29.05 | 41.5 | 79 | 11 | 149 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. | Snow |
|---|---|---|---|---|---|
| January | −4°C | −14°C | −9.1°C | 14 mm | 24 cm |
| February | −2°C | −12°C | −6.9°C | 16 mm | 21 cm |
| March | 5°C | −5°C | 0.2°C | 36 mm | 15 cm |
| April | 13°C | 2°C | 7.5°C | 76 mm | 13 cm |
| May | 20°C | 9°C | 14.4°C | 105 mm | 0 cm |
| June | 26°C | 15°C | 20.4°C | 121 mm | 0 cm |
| July | 28°C | 17°C | 22.6°C | 90 mm | 0 cm |
| August | 27°C | 16°C | 21.2°C | 94 mm | 0 cm |
| September | 23°C | 11°C | 17.0°C | 77 mm | 0 cm |
| October | 15°C | 4°C | 9.3°C | 53 mm | 1 cm |
| November | 6°C | −4°C | 0.9°C | 35 mm | 11 cm |
| December | −2°C | −11°C | −6.2°C | 21 mm | 20 cm |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00137859; 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 Spirit Lake?
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 (6).
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 USC00137859.
When is the last frost in Spirit Lake?
In Spirit Lake, the last spring frost (32°F) comes after April 28 in half of years and after May 9 in one year in ten; the first autumn frost comes before October 11 in half of years and before September 27 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 281 year in 10 after May 9; 9 in 10 after April 14
- First autumn frost, half of years before
- October 111 year in 10 before September 27; 9 in 10 before October 24
NOAA puts the median frost-free season at 164 days, and the season without a hard freeze (28°F) at 183 days.
A hard freeze (28°F) comes after April 19 in half of springs and before October 21 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Spirit Lake in zone 5a in ZIP code 51360, the nearest ZIP area. By the map's own method, the average of each year's coldest night over 1991-2020, Spirit Lake's NOAA station is in zone 5a: the coldest night of a typical year reaches −19°F (20 complete years).
Frost dates for every NOAA station in Iowa · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00137859; 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 Spirit Lake?
In a normal year in Spirit Lake, 11 days a year reach 90°F, 149 nights fall to 32°F or colder and 79 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
- 149a normal year
- Days that stay below freezing
- 71high of 32°F or less
- Days with 0.01 inch of precipitation
- 79a normal year
- Days with 1 inch of snow or more
- 14a normal year
The highest temperature in this station's record (since 1893) is 109°F, on July 27, 1894; the lowest is −39°F, on February 9, 1899.
The wettest calendar year on that record is 2018, with 49.55 in; the snowiest season is 2017–18, with 81.6 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USC00137859; records: ACIS (NOAA Regional Climate Centers), station USC00137859. Records use complete months only; a month missing more than three days is left out.
How sunny is Spirit Lake?
Over a year 75% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Spirit Lake, 4.1 kWh per square metre a day. July is the sunniest month (84%) and December the cloudiest (69%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 74% | 2.0 |
| February | 79% | 3.1 |
| March | 72% | 3.9 |
| April | 70% | 4.9 |
| May | 70% | 5.6 |
| June | 76% | 6.3 |
| July | 84% | 6.6 |
| August | 81% | 5.5 |
| September | 79% | 4.4 |
| October | 73% | 3.0 |
| November | 72% | 2.0 |
| December | 69% | 1.6 |
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 Spirit Lake need?
A normal year in Spirit Lake brings 7,678 heating degree days, 43% more than the median U.S. place (5,373), and 682 cooling degree days, 25% 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 2,751 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,533 | 0 |
| February | 1,270 | 0 |
| March | 1,011 | 0 |
| April | 587 | 2 |
| May | 253 | 33 |
| June | 39 | 152 |
| July | 7 | 246 |
| August | 16 | 176 |
| September | 140 | 67 |
| October | 509 | 6 |
| November | 942 | 0 |
| December | 1,372 | 0 |
| Year (annual) | 7,678 | 682 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00137859. 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 Spirit Lake been warmer than normal lately?
2025 averaged 47.5°F, 1.8°F above the 1991-2020 normal of 45.7°F. 4 of the 5 complete years since 2021 ran warmer than the normal.
| Year | Mean | Against normal | Precip. | Snow |
|---|---|---|---|---|
| 2021 | 48.0°F | +2.3°F | 29.90 | 27.9 |
| 2022 | 44.8°F | −0.9°F | 27.60 | 38.4 |
| 2023 | 47.7°F | +2.0°F | 26.95 | 35.8 |
| 2024 | 49.3°F | +3.6°F | 42.61 | 18.9 |
| 2025 | 47.5°F | +1.8°F | 31.09 | 34.0 |
Source: observed years: ACIS, station USC00137859. A year counts only with all twelve months complete.
How does Spirit Lake's climate compare?
Spirit Lake is warmer than 15 of the other 131 places with their own NOAA record in Iowa, and wetter than 1. Across the 7,247 U.S. stations with normals, its annual mean of 45.7°F is warmer than 22%.
In the Köppen classification computed from these normals, Spirit Lake 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 Spirit Lake share this climate record?
4 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.
- Jackson, MN3,252 people · 16 mi NE
- Okoboji, IA729 people · 2 mi S
- Orleans, IA503 people · 3 mi NE
- Terril, IA310 people · 12 mi SE
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 Spirit Lake's climate
What is the coldest month in Spirit Lake?
January, with a normal high of 24°F and a normal low of 7°F. The warmest is July (83°F by day, 63°F at night).
Does it snow in Spirit Lake?
Yes: 42 inches in a normal year, falling on 15 days with 0.1 inch or more, the most in January (9.5 inches).
What is the rainiest month in Spirit Lake?
June, with 4.77 in of precipitation in a normal year; the driest is January with 0.55 in.
What plant hardiness zone is Spirit Lake in?
The USDA's 2023 map puts Spirit Lake in zone 5a in ZIP code 51360, the nearest ZIP area. By the same method at Spirit Lake's NOAA station, the coldest night of a typical year reaches −19°F (20 years, 1991-2020): zone 5a.
How late can frost come in Spirit Lake?
In half of years the last 32°F night comes after April 28; in one year in ten it comes after May 9. Waiting until May 9 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Iowa climateThe statewide normals and every place in the state
- Milford, IA4 miles from this station, 46.0°F a year
- Lake Park, IA9 miles from this station, 46.1°F a year
- Spencer, IA18 miles from this station, 46.8°F a year
- Lakefield, MN19 miles from this station, 44.0°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made