Empire School · Photo: Ntsimp · CC0Rupert’s winters are colder but less snowy than most of the U.S.
A typical July afternoon reaches 89°, a January night drops to 20°, and about 21 inches of snow falls in a normal winter.
A year in Rupert at a glance
Each month’s typical high and low, and what it brings.
What stands out about Rupert’s climate
Compared with towns across the U.S., with Rupert’s place in Idaho beside it.
What a year in Rupert feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 150 frost-free days a year
In half of years the last 32° night comes by May 7 and the first by October 4. Frost and day counts come from NOAA’s station at Burley Muni Airport, 7 miles from the town’s center, at about the same height.
The 2023 USDA map puts Rupert’s center in zone 6a: the coldest night of a typical winter, averaged over 1991–2020, reaches about −6°. 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 21 inches of snow a winter
Snow, measured at Minidoka Dam, ID, falls mostly in January. Precipitation (rain plus melted snow) adds up to 10 inches a year; May is the wettest month and July the driest. Rain or snow falls on about 66 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in Rupert
93% 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 Burley Muni Airport.
Living with Rupert’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
150 frost-free days in zone 6a. The last frost comes by May 7 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 4.
Months with highs of 62–84° and lows of 40° or more: May, June and September. 1.6 miles of trails are waiting.
Parks & trails →Of the yearly building losses FEMA expects in Rupert from natural hazards, river flooding is the largest share (33%); heat waves, cold waves, winter storms and ice storms together are 31%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Rupert and similar climates
TownRatings has no climate map of the towns around Rupert yet.
Climates most like Rupert’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 |
|---|---|---|---|---|
| Rupert, ID | 20° | 89° | 10" | 21" |
| White Rock, NM | 18° | 89° | 13" | 20" |
| Richfield, UT | 16° | 90° | 11" | 18" |
| Gardnerville Ranchos, NV | 23° | 90° | 11" | 22" |
| Montrose, CO | 15° | 90° | 10" | 22" |
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 Rupert averaged 2.0° warmer than the 1900s. The biggest change is in January (+4.3°).
A bigger shift than in 88% 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 Rupert compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Rupert’s place among Idaho’s.
Rupert weather by month
Highs, lows and precipitation from NOAA’s grid at Rupert’s center; snow, wet days and snow on the ground from Minidoka Dam, ID. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | 30-yr range |
|---|---|---|---|---|---|---|
| January | 37° | 20° | 1.1" | 6.7" | 9 | 17° – 37° |
| February | 42° | 22° | 0.7" | 4.2" | 7 | 22° – 40° |
| March | 52° | 29° | 0.9" | 1.2" | 6 | 34° – 45° |
| April | 60° | 33° | 1.0" | 0.5" | 7 | 42° – 51° |
| May | 69° | 41° | 1.4" | 0.0" | 7 | 48° – 60° |
| June | 79° | 48° | 0.7" | 0.0" | 4 | 58° – 69° |
| July | 89° | 54° | 0.3" | 0.0" | 2 | 62° – 76° |
| August | 87° | 52° | 0.4" | 0.0" | 3 | 65° – 73° |
| September | 78° | 44° | 0.7" | 0.0" | 4 | 57° – 64° |
| October | 63° | 34° | 0.8" | 0.7" | 5 | 41° – 55° |
| November | 48° | 26° | 0.8" | 2.6" | 6 | 28° – 43° |
| December | 37° | 19° | 1.1" | 4.6" | 8 | 22° – 34° |
| Year | 62° | 35° | 9.8" | 20.5" | 66 |
How much a month can swing
A normal is an average. January swings the most: from 1991 to 2020 its average ranged from 17° to 37°. September is the most reliable, staying within 7°.
Where Rupert’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 Rupert’s center.
- Snow: Minidoka Dam, ID.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Burley Muni Airport, 7 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 Rupert’s climate
What is the weather like in Rupert?
A typical July afternoon reaches 89°, a January night drops to 20°, and about 21 inches of snow falls in a normal winter. Colder January nights than 62% of U.S. towns; hotter July afternoons than 71% of U.S. towns.
How cold does it get in Rupert in winter?
December nights average 19°. About 146 nights a year reach 32° or below and 3 reach 0° or below. In the coldest December of the last 30 years the month averaged 22°.
How much snow does Rupert get?
About 21 inches in a normal winter at Minidoka Dam, ID, most of it in January.
How hot does it get in Rupert?
July, with a typical high of 89° and a low of 54°. About 33 days a year reach 90° and 2 reach 100° (Burley Muni Airport).
When is the first and last frost in Rupert?
In half of years the last spring frost (32°) comes by May 7 and the first fall frost by October 4, about 150 frost-free days, at Burley Muni Airport.
What growing zone is Rupert in?
Zone 6a on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about −6°.
What is the best time of year to visit Rupert?
By one simple rule (highs of 62–84° and lows of 40° or more), May, June and September. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Rupert getting warmer?
Yes: 1991–2020 averaged 2.0° warmer than 1901–2000 on NOAA’s grid. A bigger shift than 88% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Rupert.
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.