Jamestown, North Dakota climate: Normal weather by month, frost dates and records
Jamestown's normal year runs from 1°F January nights to 81°F July afternoons, with 19.8 inches of precipitation a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 5.2°C, January lows of −17°C, July highs of 27°C, 504 mm of precipitation a year.
- NOAA stationJamestown Municipal Airport
- Station IDUSW00014919
- Location46.93°N 98.67°W
- Elevation1,494 ft (455 m)
- From the center2 miles
- Population15,789
On October 23, the normal high in Jamestown is 51°F and the normal low 30°F, and the chance of measurable rain or snow is 22%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Jamestown.
- Jan 19° 1°
- Feb 24° 5°
- Mar 37° 17°
- Apr 53° 30°
- May 67° 43°
- Jun 76° 54°
- Jul 81° 58°
- Aug 80° 55°
- Sep 71° 46°
- Oct 55° 33°
- Nov 38° 19°
- Dec 24° 7°
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 Jamestown each month?
July is the warmest month, with normal highs of 81°F; January the coldest, with normal lows of 1°F. The most precipitation falls in July (3.58 in), the least in January (0.31 in).
Each month has its own page with the day-by-day normals, the month's records and its recent years:
| Month | High | Low | Mean | Precip. | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|
| January | 19°F | 1°F | 10.1°F | 0.31 | 5 | <1 | 31 | 8 h 50 min |
| February | 24°F | 5°F | 14.1°F | 0.37 | 5 | <1 | 27 | 10 h 20 min |
| March | 37°F | 17°F | 27.0°F | 0.69 | 6 | <1 | 28 | 11 h 50 min |
| April | 53°F | 30°F | 41.4°F | 1.24 | 7 | <1 | 17 | 13 h 30 min |
| May | 67°F | 43°F | 54.7°F | 3.26 | 11 | <1 | 4 | 15 h |
| June | 76°F | 54°F | 65.0°F | 3.37 | 12 | 1 | <1 | 15 h 50 min |
| July | 81°F | 58°F | 69.7°F | 3.58 | 11 | 3 | <1 | 15 h 30 min |
| August | 80°F | 55°F | 67.5°F | 2.42 | 9 | 3 | <1 | 14 h 20 min |
| September | 71°F | 46°F | 58.4°F | 2.06 | 8 | 1 | 1 | 12 h 40 min |
| October | 55°F | 33°F | 43.8°F | 1.67 | 7 | <1 | 14 | 11 h |
| November | 38°F | 19°F | 28.4°F | 0.53 | 5 | <1 | 27 | 9 h 30 min |
| December | 24°F | 7°F | 15.8°F | 0.34 | 6 | <1 | 31 | 8 h 30 min |
| Year (annual) | 52°F | 31°F | 41.3°F | 19.84 | 91 | 9 | 181 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. |
|---|---|---|---|---|
| January | −7°C | −17°C | −12.2°C | 8 mm |
| February | −5°C | −15°C | −9.9°C | 9 mm |
| March | 3°C | −8°C | −2.8°C | 18 mm |
| April | 12°C | −1°C | 5.2°C | 31 mm |
| May | 19°C | 6°C | 12.6°C | 83 mm |
| June | 24°C | 12°C | 18.3°C | 86 mm |
| July | 27°C | 15°C | 20.9°C | 91 mm |
| August | 27°C | 13°C | 19.7°C | 61 mm |
| September | 22°C | 8°C | 14.7°C | 52 mm |
| October | 13°C | 0°C | 6.6°C | 42 mm |
| November | 3°C | −7°C | −2.0°C | 13 mm |
| December | −4°C | −14°C | −9.0°C | 9 mm |
NOAA publishes no 1991-2020 snowfall normal for this station. Jamestown's own co-op station Jamestown State Hosp does: 46 inches of snow in a normal year (see the other stations below).
Source: NOAA NCEI 1991-2020 monthly normals, station USW00014919; 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 Jamestown?
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 (8).
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 USW00014919.
When is the last frost in Jamestown?
In Jamestown, the last spring frost (32°F) comes after May 11 in half of years and after May 24 in one year in ten; the first autumn frost comes before September 28 in half of years and before September 15 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 111 year in 10 after May 24; 9 in 10 after April 28
- First autumn frost, half of years before
- September 281 year in 10 before September 15; 9 in 10 before October 9
NOAA puts the median frost-free season at 138 days, and the season without a hard freeze (28°F) at 157 days.
A hard freeze (28°F) comes after May 1 in half of springs and before October 6 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Jamestown in zone 4b in ZIP code 58405, the nearest ZIP area. By the map's own method, the average of each year's coldest night over 1991-2020, Jamestown's NOAA station is in zone 4b: the coldest night of a typical year reaches −25°F (30 complete years).
Frost dates for every NOAA station in North Dakota · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USW00014919; 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 Jamestown?
In a normal year in Jamestown, 9 days a year reach 90°F, 181 nights fall to 32°F or colder and 91 days bring measurable precipitation.
- Days at 90°F or more
- 9a normal year
- Days at 100°F or more
- fewer than 1a normal year
- Nights at 32°F or colder
- 181a normal year
- Days that stay below freezing
- 92high of 32°F or less
- Days with 0.01 inch of precipitation
- 91a normal year
The highest temperature in this station's record (since 1948) is 108°F, on July 11, 1973; the lowest is −37°F, on December 23, 1983.
The wettest calendar year on that record is 1993, with 30.19 in; the snowiest season is 1949–50, with 103.8 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USW00014919; records: ACIS (NOAA Regional Climate Centers), station USW00014919. Records use complete months only; a month missing more than three days is left out.
How humid and windy is Jamestown, and how clear are its skies?
The summer (June-August) dew point averages 57°F. The muggiest month is July, with an average dew point of 58°F; the driest air comes in December (7°F). April is the windiest month (12.5 mph on average), and August has the most clear or nearly clear hours (79%).
| Month | Dew point | Humidity | Afternoon humidity | Wind | Clear or few clouds | Overcast |
|---|---|---|---|---|---|---|
| January | 7°F | 80% | 72% | 11.8 mph | – | – |
| February | 11°F | 79% | 70% | 11.9 mph | – | – |
| March | 25°F | 70% | 52% | 12.5 mph | – | – |
| April | 34°F | 59% | 39% | 12.5 mph | 56% | 27% |
| May | 48°F | 64% | 47% | 11.0 mph | 59% | 22% |
| June | 57°F | 68% | 49% | 9.9 mph | 70% | 14% |
| July | 58°F | 70% | 49% | 8.4 mph | 76% | 9% |
| August | 54°F | 70% | 47% | 9.4 mph | 79% | 9% |
| September | 40°F | 65% | 43% | 11.0 mph | – | – |
| October | 28°F | 72% | 54% | 11.9 mph | – | – |
| November | 15°F | 78% | 67% | 12.0 mph | – | – |
| December | 7°F | 81% | 75% | 11.6 mph | – | – |
Source: NOAA NCEI 1991-2020 hourly normals, station USW00014919. Monthly averages of all hours; afternoon humidity at 3 p.m. local standard time; sky as the share of hours NOAA's observations rate clear or few clouds (a dash where NOAA publishes no sky value).
How sunny is Jamestown?
Over a year 77% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Jamestown, 4.0 kWh per square metre a day. February is the sunniest month (84%) and November the cloudiest (70%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 81% | 1.9 |
| February | 84% | 3.0 |
| March | 77% | 4.0 |
| April | 73% | 5.0 |
| May | 72% | 5.7 |
| June | 76% | 6.4 |
| July | 84% | 6.6 |
| August | 82% | 5.5 |
| September | 78% | 4.2 |
| October | 70% | 2.7 |
| November | 70% | 1.7 |
| December | 70% | 1.3 |
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 Jamestown need?
A normal year in Jamestown brings 9,010 heating degree days, 68% more than the median U.S. place (5,373), and 419 cooling degree days, 54% 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 2,163 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,702 | 0 |
| February | 1,425 | 0 |
| March | 1,178 | 0 |
| April | 708 | 0 |
| May | 335 | 16 |
| June | 83 | 82 |
| July | 21 | 165 |
| August | 44 | 123 |
| September | 231 | 33 |
| October | 659 | 2 |
| November | 1,098 | 0 |
| December | 1,527 | 0 |
| Year (annual) | 9,010 | 419 |
Source: NOAA NCEI 1991-2020 monthly normals, station USW00014919. 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 Jamestown been warmer than normal lately?
2025 averaged 42.6°F, 1.3°F above the 1991-2020 normal of 41.3°F. 4 of the 5 complete years since 2021 ran warmer than the normal.
| Year | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 45.3°F | +4.0°F | – |
| 2022 | 40.4°F | −0.9°F | – |
| 2023 | 42.8°F | +1.5°F | 20.55 |
| 2024 | 45.3°F | +4.0°F | 19.41 |
| 2025 | 42.6°F | +1.3°F | 16.71 |
Over 75 complete years from 1949 to 2025, the station's annual mean temperature rose at a fitted 5.2°F per century (+0.29°C per decade). A fitted rate summarizes the whole record; single years swing well above and below it.
Source: observed years: ACIS, station USW00014919; trend: NOAA GHCN-Monthly v4. A year counts only with all twelve months complete.
How does Jamestown's climate compare?
Jamestown is warmer than 47 of the other 91 places with their own NOAA record in North Dakota, and wetter than 47. Across the 7,247 U.S. stations with normals, its annual mean of 41.3°F is warmer than 8%.
In the Köppen classification computed from these normals, Jamestown is Dwb: continental, dry-winter, 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 Jamestown 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.
- Wimbledon, ND179 people · 20 mi NE
- Spiritwood Lake, ND94 people · 11 mi N
- Buchanan, ND85 people · 12 mi NW
- Montpelier, ND84 people · 16 mi S
- Spiritwood, ND24 people · 8 mi E
- Ypsilanti, ND12 people · 11 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.
What do Jamestown's other NOAA stations record?
One more NOAA station keeps 1991-2020 normals in or near Jamestown. This page uses Jamestown Municipal Airport; the other differs by site and elevation:
| Station | From the center | Elevation | Year | Jan low | Jul high | Precip. | Snow | Last frost |
|---|---|---|---|---|---|---|---|---|
| Jamestown State Hosp USC00324418 | 2 mi S | 1,467 ft | 41.3°F | 0°F | 82°F | 21.1 | 46 | May 8 |
Source: NOAA NCEI 1991-2020 normals for each station. Last frost: the median last spring date of 32°F.
Questions about Jamestown's climate
What is the coldest month in Jamestown?
January, with a normal high of 19°F and a normal low of 1°F. The warmest is July (81°F by day, 58°F at night).
Does it snow in Jamestown?
Yes. NOAA publishes no 1991-2020 snowfall normal for Jamestown's NOAA station; Jamestown's own co-op station Jamestown State Hosp records 46 inches of snow in a normal year.
What is the rainiest month in Jamestown?
July, with 3.58 in of precipitation in a normal year; the driest is January with 0.31 in.
What plant hardiness zone is Jamestown in?
The USDA's 2023 map puts Jamestown in zone 4b in ZIP code 58405, the nearest ZIP area. By the same method at Jamestown's NOAA station, the coldest night of a typical year reaches −25°F (30 years, 1991-2020): zone 4b.
How late can frost come in Jamestown?
In half of years the last 32°F night comes after May 11; in one year in ten it comes after May 24. Waiting until May 24 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Jamestown in OctoberThis month day by day, its records and recent years
- North Dakota climateThe statewide normals and every place in the state
- Edmunds Arrowwood Ref, ND25 miles from this station, 42.2°F a year
- Gackle, ND30 miles from this station, 42.1°F a year
- Valley City, ND30 miles from this station, 40.5°F a year
- Edgeley, ND39 miles from this station, 42.5°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made