Photo: Andrew Filer · CC BY-SA 2.0Arthur sits near the bottom of U.S. towns for winter warmth
In July the day’s top temperature is typically 82°. Precipitation is light here, less than falls on 88% of U.S. towns. Decade by decade the climate has edged up, 1.2° above 1901–2000. Seedlings are safe outdoors from about May 9, with the first autumn frost due around October 1.
A year in Arthur at a glance
Each month’s typical high and low, and what it brings.
What stands out about Arthur’s climate
Compared with towns across the U.S., with Arthur’s place in North Dakota beside it.
What a year in Arthur feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 143 frost-free days a year
In half of years the last 32° night comes by May 9 and the first by October 1. Frost and day counts come from NOAA’s station at Casselton Agronomy Farm, ND, 16 miles from the town’s center, at about the same height.
The 2023 USDA map puts Arthur’s center in zone 4a: the coldest night of a typical winter, averaged over 1991–2020, reaches about −27°. Plant labels use the zone; frost dates tell you when to plant.
Freezing nights by month
Average nights at or below 32°
90° days by month
Average days at 90° or more
About 37 inches of snow a winter
Snow, measured at Casselton Agronomy Farm, ND, falls mostly in January and December. Precipitation (rain plus melted snow) adds up to 23 inches a year; June is the wettest month and February the driest. Rain or snow falls on about 84 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in Arthur
95% of the work is heating, so the furnace matters far more than the air conditioner. Months averaging under 55° run from October through April.
Degree days add up how far each day’s average falls below (heating) or rises above (cooling) 65° over a year. NOAA normals at Casselton Agronomy Farm, ND.
Living with Arthur’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
143 frost-free days in zone 4a. The last frost comes by May 9 in half of years, so many gardeners wait a week or two past that to set out tomatoes. The first fall frost comes by Oct 1.
Months with highs of 62–84° and lows of 40° or more: May, June, July, August and September. 1.0 miles of trails are waiting.
Parks & trails →Of the yearly building losses FEMA expects in Arthur from natural hazards, strong wind is the largest share (34%); heat waves, cold waves, winter storms and ice storms together are 22%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Arthur and similar climates
TownRatings has no climate map of the towns around Arthur yet.
Climates most like Arthur’s, farther away
TownRatings’ own comparison of NOAA 1991–2020 normals, not a NOAA product: places of 5,000+ at least 150 miles away, one per state, closest on January low, July high, precipitation and snow.
| Town | Jan. low | July high | Precip. | Snow |
|---|---|---|---|---|
| Arthur, ND | −1° | 82° | 23" | 37" |
| Watertown, SD | 2° | 81° | 25" | 41" |
| Litchfield, MN | 4° | 82° | 28" | 41" |
| Spirit Lake, IA | 7° | 83° | 31" | 42" |
| Gunnison, CO | 0° | 82° | 12" | 50" |
Temperatures and precipitation come from NOAA’s 5 km grid; snow and day counts from the stations named on this page.
Warmer than it used to be
The last 30 years in Arthur averaged 1.2° warmer than the 1900s. The biggest change is in January (+3.7°).
A smaller shift than in 59% of U.S. towns.
Change by month
The two periods overlap (1991–2000 is in both), which makes the gap a little smaller than it would be between separate periods.
How Arthur compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Arthur’s place among North Dakota’s.
Arthur weather by month
Highs, lows and precipitation from NOAA’s grid at Arthur’s center; snow, wet days and snow on the ground from Casselton Agronomy Farm, ND. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | 30-yr range |
|---|---|---|---|---|---|---|
| January | 17° | −1° | 0.6" | 7.4" | 4 | −5° – 23° |
| February | 23° | 3° | 0.5" | 6.6" | 5 | −1° – 27° |
| March | 36° | 17° | 1.0" | 6.2" | 5 | 17° – 41° |
| April | 54° | 31° | 1.4" | 3.3" | 6 | 32° – 51° |
| May | 68° | 43° | 3.1" | 0.0" | 11 | 50° – 62° |
| June | 77° | 55° | 3.8" | 0.0" | 11 | 61° – 70° |
| July | 82° | 58° | 3.5" | 0.0" | 9 | 63° – 76° |
| August | 80° | 56° | 2.8" | 0.0" | 8 | 62° – 72° |
| September | 72° | 47° | 2.5" | 0.0" | 7 | 54° – 64° |
| October | 55° | 34° | 2.0" | 0.7" | 7 | 37° – 51° |
| November | 37° | 20° | 0.8" | 4.4" | 5 | 16° – 41° |
| December | 23° | 6° | 0.7" | 8.1" | 5 | 1° – 24° |
| Year | 52° | 31° | 22.7" | 36.7" | 84 |
How much a month can swing
A normal is an average. January swings the most: from 1991 to 2020 its average ranged from -5° to 23°. June is the most reliable, staying within 9°.
Where Arthur’s numbers come from
Normals are 30-year averages, not a forecast. How TownRatings reads climate data →
- Temperatures and precipitation: NOAA’s gridded 1991–2020 normals for the 5 km cell at Arthur’s center.
- Snow: Casselton Agronomy Farm, ND.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Casselton Agronomy Farm, ND, 16 miles from the town’s center, at about the same height; the nearest station that passes our checks for distance, height and agreement with the grid.
- Growing zone: USDA Plant Hardiness Zone Map, 2023. USDA Agricultural Research Service and PRISM Group, Oregon State University, prism.oregonstate.edu/phzm, accessed 8 Oct 2026.
- Then and now: NOAA’s gridded normals for 1901–2000 at the same cell.
- Storms and extremes: FEMA National Risk Index (expected annual losses to buildings).
Common questions about Arthur’s climate
What is the weather like in Arthur?
A typical July afternoon reaches 82°, a January night drops to −1°, and about 37 inches of snow falls in a normal winter. Colder January nights than all but 40 U.S. towns; cooler July afternoons than 84% of U.S. towns.
How cold does it get in Arthur in winter?
January nights average −1°. About 182 nights a year reach 32° or below and 46 reach 0° or below. In the coldest January of the last 30 years the month averaged −5°.
How much snow does Arthur get?
About 37 inches in a normal winter at Casselton Agronomy Farm, ND, most of it in January and December.
How hot does it get in Arthur?
July, with a typical high of 82° and a low of 58°. About 10 days a year reach 90° (Casselton Agronomy Farm, ND).
When is the first and last frost in Arthur?
In half of years the last spring frost (32°) comes by May 9 and the first fall frost by October 1, about 143 frost-free days, at Casselton Agronomy Farm, ND.
What growing zone is Arthur in?
Zone 4a on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about −27°.
What is the best time of year to visit Arthur?
By one simple rule (highs of 62–84° and lows of 40° or more), May, June, July, August and September. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Arthur getting warmer?
Yes: 1991–2020 averaged 1.2° warmer than 1901–2000 on NOAA’s grid. A smaller shift than 59% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Arthur.
Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000; USDA/PRISM 2023 hardiness zones; FEMA National Risk Index. Today’s forecast: National Weather Service.