Photo: Tomás Del Coro from Las Vegas, Nevada, USA · CC BY-SA 2.0Mountain Home AFB reaches 100° on about 17 days a year, more than 94% of U.S. towns
Deep winter brings January lows near 25°. Winter and summer sit 69° apart. Precipitation is light here, less than falls on 98% of U.S. towns. Picnics, hikes and garden evenings suit May, June and September, with highs of 73–83°.
A year in Mountain Home AFB at a glance
Each month’s typical high and low, and what it brings.
What stands out about Mountain Home AFB’s climate
Compared with towns across the U.S., with Mountain Home AFB’s place in Idaho beside it.
What a year in Mountain Home AFB feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 157 frost-free days a year
In half of years the last 32° night comes by May 2 and the first by October 8. Frost and day counts come from NOAA’s station at Mtn Home, ID, 9 miles from the town’s center, 140 ft higher.
The 2023 USDA map puts Mountain Home AFB’s center in zone 7a: the coldest night of a typical winter, averaged over 1991–2020, reaches about 1°. 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 9 inches of rain a year
December is the wettest month and August the driest.
Rain + melted snow by month
Inches of water
Heating and cooling a home in Mountain Home AFB
85% of the work is heating. 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 Mtn Home, ID.
Living with Mountain Home AFB’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
157 frost-free days in zone 7a. The last frost comes by May 2 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 8.
Months with highs of 62–84° and lows of 40° or more: May, June and September. 27 miles of trails are waiting.
Parks & trails →Of the yearly building losses FEMA expects in Mountain Home AFB from natural hazards, wildfire is the largest share (56%); heat waves, cold waves, winter storms and ice storms together are 8%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Mountain Home AFB and similar climates
TownRatings has no climate map of the towns around Mountain Home AFB yet.
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 Mountain Home AFB averaged 1.4° warmer than the 1900s. The biggest change is in January (+3.0°).
A bigger shift than in 51% 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 Mountain Home AFB compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Mountain Home AFB’s place among Idaho’s.
Mountain Home AFB weather by month
Highs, lows and precipitation from NOAA’s grid at Mountain Home AFB’s center. 1991–2020 normals.
| Month | High | Low | Rain + melt | 30-yr range |
|---|---|---|---|---|
| January | 41° | 25° | 1.2" | 24° – 39° |
| February | 47° | 28° | 0.8" | 30° – 45° |
| March | 57° | 33° | 0.9" | 40° – 50° |
| April | 64° | 37° | 0.9" | 46° – 57° |
| May | 73° | 46° | 1.0" | 53° – 65° |
| June | 83° | 52° | 0.7" | 62° – 75° |
| July | 94° | 60° | 0.2" | 67° – 82° |
| August | 92° | 58° | 0.2" | 69° – 78° |
| September | 82° | 49° | 0.3" | 61° – 69° |
| October | 67° | 38° | 0.6" | 46° – 59° |
| November | 51° | 30° | 0.9" | 33° – 47° |
| December | 40° | 25° | 1.2" | 27° – 38° |
| Year | 66° | 40° | 8.8" |
How much a month can swing
A normal is an average. February swings the most: from 1991 to 2020 its average ranged from 30° to 45°. September is the most reliable, staying within 7°.
Where Mountain Home AFB’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 Mountain Home AFB’s center.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Mtn Home, ID, 9 miles from the town’s center, 140 ft higher; 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 Mountain Home AFB’s climate
What is the weather like in Mountain Home AFB?
A typical July afternoon reaches 94°, a January night drops to 25°. Milder January nights than 63% of U.S. towns; hotter July afternoons than 93% of U.S. towns.
How cold does it get in Mountain Home AFB in winter?
December nights average 25°. About 139 nights a year reach 32° or below. In the coldest December of the last 30 years the month averaged 27°.
How hot does it get in Mountain Home AFB?
July, with a typical high of 94° and a low of 60°. About 65 days a year reach 90° and 17 reach 100° (Mtn Home, ID).
When is the first and last frost in Mountain Home AFB?
In half of years the last spring frost (32°) comes by May 2 and the first fall frost by October 8, about 157 frost-free days, at Mtn Home, ID.
What growing zone is Mountain Home AFB in?
Zone 7a on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about 1°.
What is the best time of year to visit Mountain Home AFB?
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 Mountain Home AFB getting warmer?
Yes: 1991–2020 averaged 1.4° warmer than 1901–2000 on NOAA’s grid. A bigger shift than 51% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Mountain Home AFB.
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.