North Fork Payette River Bridge · Photo: Paulboehlke · CC BY-SA 4.0Precipitation in Smiths Ferry trails that of 86% of U.S. towns: 29 inches a year
The coldest hours of a January night bottom out at 19° on average. In July, afternoons here are cooler than in 66% of U.S. towns. Since 1901–2000, the year has warmed by 1.2°, most of all in January. Plan time outside from June to September, when highs sit at 72–83°.
A year in Smiths Ferry at a glance
Each month’s typical high and low, and what it brings.
What stands out about Smiths Ferry’s climate
Compared with towns across the U.S., with Smiths Ferry’s place in Idaho beside it.
What a year in Smiths Ferry feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 110 frost-free days a year
In half of years the last 32° night comes by May 30 and the first by September 19. Frost and day counts come from NOAA’s station at Cascade 1 Nw, ID, 16 miles from the town’s center, 300 ft higher.
The 2023 USDA map puts Smiths Ferry’s center in zone 5b: the coldest night of a typical winter, averaged over 1991–2020, reaches about −13°. 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 69 inches of snow a winter
Snow, measured at Garden Valley, ID, falls mostly in January and December. Precipitation (rain plus melted snow) adds up to 29 inches a year; December is the wettest month and August the driest. Rain or snow falls on about 98 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in Smiths Ferry
98% 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 Cascade 1 Nw, ID.
Living with Smiths Ferry’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
110 frost-free days in zone 5b. The last frost comes by May 30 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 19.
Months with highs of 62–84° and lows of 40° or more: June, July, August and September. 6.3 miles of trails are waiting.
Parks & trails →Of the yearly building losses FEMA expects in Smiths Ferry from natural hazards, river flooding is the largest share (44%); heat waves, cold waves, winter storms and ice storms together are 1%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Smiths Ferry and similar climates
TownRatings has no climate map of the towns around Smiths Ferry yet.
Climates most like Smiths Ferry’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 |
|---|---|---|---|---|
| Smiths Ferry, ID | 19° | 83° | 29" | 69" |
| Ann Arbor, MI | 16° | 83° | 33" | 61" |
| Lewiston, NY | 19° | 81° | 34" | 72" |
| Spearfish, SD | 15° | 86° | 25" | 71" |
| Montrose-Ghent, OH | 20° | 83° | 39" | 65" |
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 Smiths Ferry averaged 1.2° warmer than the 1900s. The biggest change is in January (+2.8°).
A smaller shift than in 64% 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 Smiths Ferry compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Smiths Ferry’s place among Idaho’s.
Smiths Ferry weather by month
Highs, lows and precipitation from NOAA’s grid at Smiths Ferry’s center; snow, wet days and snow on the ground from Garden Valley, ID. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 33° | 19° | 4.0" | 22.8" | 12 | 30 | 19° – 33° |
| February | 38° | 21° | 3.3" | 10.2" | 11 | 24 | 24° – 37° |
| March | 46° | 26° | 3.4" | 3.5" | 11 | 13 | 31° – 42° |
| April | 53° | 31° | 2.5" | 0.4" | 10 | 0 | 36° – 48° |
| May | 63° | 39° | 2.4" | 0.0" | 9 | 0 | 44° – 57° |
| June | 72° | 45° | 1.7" | 0.0" | 7 | 0 | 54° – 67° |
| July | 83° | 51° | 0.5" | 0.0" | 3 | 0 | 56° – 74° |
| August | 83° | 51° | 0.5" | 0.0" | 2 | 0 | 60° – 70° |
| September | 73° | 43° | 1.0" | 0.0" | 4 | 0 | 54° – 63° |
| October | 57° | 34° | 2.0" | 0.3" | 7 | 0 | 38° – 52° |
| November | 41° | 26° | 3.3" | 8.0" | 11 | 4 | 26° – 40° |
| December | 32° | 19° | 4.7" | 24.2" | 13 | 23 | 19° – 30° |
| Year | 56° | 34° | 29.4" | 69.4" | 98 | 94 |
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 74°. September is the most reliable, staying within 9°.
Where Smiths Ferry’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 Smiths Ferry’s center.
- Snow: Garden Valley, ID.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Cascade 1 Nw, ID, 16 miles from the town’s center, 300 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 Smiths Ferry’s climate
What is the weather like in Smiths Ferry?
A typical July afternoon reaches 83°, a January night drops to 19°, and about 69 inches of snow falls in a normal winter. Colder January nights than 63% of U.S. towns; cooler July afternoons than 66% of U.S. towns.
How cold does it get in Smiths Ferry in winter?
December nights average 19°. About 225 nights a year reach 32° or below and 18 reach 0° or below. In the coldest December of the last 30 years the month averaged 19°.
How much snow does Smiths Ferry get?
About 69 inches in a normal winter at Garden Valley, ID, most of it in January and December, with snow on the ground about 94 days a year.
How hot does it get in Smiths Ferry?
July, with a typical high of 83° and a low of 51°. About 9 days a year reach 90° (Cascade 1 Nw, ID).
When is the first and last frost in Smiths Ferry?
In half of years the last spring frost (32°) comes by May 30 and the first fall frost by September 19, about 110 frost-free days, at Cascade 1 Nw, ID.
What growing zone is Smiths Ferry in?
Zone 5b on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about −13°.
What is the best time of year to visit Smiths Ferry?
By one simple rule (highs of 62–84° and lows of 40° or more), June, July, August and September. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Smiths Ferry getting warmer?
Yes: 1991–2020 averaged 1.2° warmer than 1901–2000 on NOAA’s grid. A smaller shift than 64% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Smiths Ferry.
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.