Independent Order of Odd Fellows Hall · Photo: Ntsimp · CC0Midwinter lows in Ashton sink below those of 93% of U.S. towns
In July the day’s top temperature is typically 83°. Precipitation is light here, less than falls on 91% of U.S. towns. Since 1901–2000, the year has warmed by 1.4°, most of all in March. Garden planting can start around May 21; autumn frost returns near September 21.
A year in Ashton at a glance
Each month’s typical high and low, and what it brings.
What stands out about Ashton’s climate
Compared with towns across the U.S., with Ashton’s place in Idaho beside it.
What a year in Ashton feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 121 frost-free days a year
In half of years the last 32° night comes by May 21 and the first by September 21. Frost and day counts come from NOAA’s station at Ashton 1n, ID, 0.4 miles from the town’s center, at about the same height.
The 2023 USDA map puts Ashton’s center in zone 5a: the coldest night of a typical winter, averaged over 1991–2020, reaches about −15°. 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 70 inches of snow a winter
Snow, measured at Ashton 1n, ID, falls mostly in January and December. Precipitation (rain plus melted snow) adds up to 17 inches a year; May is the wettest month and July the driest. Rain or snow falls on about 78 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in Ashton
97% of the work is heating, so the furnace matters far more than the air conditioner. Months averaging under 55° run from October through May.
Degree days add up how far each day’s average falls below (heating) or rises above (cooling) 65° over a year. NOAA normals at Ashton 1n, ID.
Living with Ashton’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
121 frost-free days in zone 5a. The last frost comes by May 21 in half of years, so many gardeners wait a week or two past that to set out tomatoes. The first fall frost comes by Sep 21.
Months with highs of 62–84° and lows of 40° or more: June, July and August.
Parks & trails →Of the yearly building losses FEMA expects in Ashton from natural hazards, avalanches are the largest share (42%); heat waves, cold waves, winter storms and ice storms together are 10%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Ashton and similar climates
TownRatings has no climate map of the towns around Ashton yet.
Climates most like Ashton’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 |
|---|---|---|---|---|
| Ashton, ID | 11° | 83° | 17" | 70" |
| Great Falls, MT | 13° | 84° | 13" | 66" |
| Durango, CO | 12° | 86° | 18" | 64" |
| Ranchettes, WY | 16° | 85° | 16" | 65" |
| Flagstaff, AZ | 16° | 84° | 18" | 90" |
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 Ashton averaged 1.4° warmer than the 1900s. The biggest change is in March (+3.7°).
A bigger shift than in 54% 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 Ashton compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Ashton’s place among Idaho’s.
Ashton weather by month
Highs, lows and precipitation from NOAA’s grid at Ashton’s center; snow, wet days and snow on the ground from Ashton 1n, ID. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 28° | 11° | 1.8" | 19.8" | 9 | 31 | 12° – 27° |
| February | 33° | 13° | 1.3" | 10.7" | 7 | 29 | 16° – 31° |
| March | 43° | 22° | 1.3" | 5.3" | 7 | 25 | 24° – 40° |
| April | 54° | 29° | 1.6" | 2.0" | 7 | 4 | 34° – 47° |
| May | 65° | 37° | 2.1" | 0.0" | 8 | 0 | 45° – 56° |
| June | 73° | 43° | 1.8" | 0.0" | 6 | 0 | 53° – 65° |
| July | 83° | 49° | 0.8" | 0.0" | 3 | 0 | 56° – 73° |
| August | 83° | 47° | 0.9" | 0.0" | 4 | 0 | 60° – 68° |
| September | 72° | 39° | 1.2" | 0.0" | 5 | 0 | 52° – 60° |
| October | 57° | 30° | 1.5" | 1.6" | 5 | 1 | 34° – 50° |
| November | 41° | 20° | 1.4" | 10.5" | 7 | 10 | 22° – 38° |
| December | 29° | 12° | 1.8" | 20.2" | 10 | 26 | 15° – 27° |
| Year | 55° | 29° | 17.4" | 70.1" | 78 | 125 |
How much a month can swing
A normal is an average. July swings the most: from 1991 to 2020 its average ranged from 56° to 73°. September is the most reliable, staying within 8°.
Where Ashton’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 Ashton’s center.
- Snow: Ashton 1n, ID (NOAA station in town).
- Frost, freezing nights, 90° and 100° days, heating and cooling: Ashton 1n, ID, 0.4 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 Ashton’s climate
What is the weather like in Ashton?
A typical July afternoon reaches 83°, a January night drops to 11°, and about 70 inches of snow falls in a normal winter. Colder January nights than 93% of U.S. towns; cooler July afternoons than 68% of U.S. towns.
How cold does it get in Ashton in winter?
January nights average 11°. About 190 nights a year reach 32° or below and 14 reach 0° or below. In the coldest January of the last 30 years the month averaged 12°.
How much snow does Ashton get?
About 70 inches in a normal winter at Ashton 1n, ID, most of it in January and December, with snow on the ground about 125 days a year.
How hot does it get in Ashton?
July, with a typical high of 83° and a low of 49°. About 9 days a year reach 90° (Ashton 1n, ID).
When is the first and last frost in Ashton?
In half of years the last spring frost (32°) comes by May 21 and the first fall frost by September 21, about 121 frost-free days, at Ashton 1n, ID.
What growing zone is Ashton in?
Zone 5a on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about −15°.
What is the best time of year to visit Ashton?
By one simple rule (highs of 62–84° and lows of 40° or more), June, July and August. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Ashton getting warmer?
Yes: 1991–2020 averaged 1.4° warmer than 1901–2000 on NOAA’s grid. A bigger shift than 54% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Ashton.
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.