Register Rock · Photo: JERRYE & ROY KLOTZ MD · CC BY-SA 3.0Rockland is drier than 93% of U.S. towns: 15 inches of precipitation a year
January mornings start at about 16°. Winter nights are cold: in January they are colder than in 82% of U.S. towns. Compared with 1901–2000, the average now sits 1.0° higher. If you like long walks, June and September offer highs of 76–77°.
A year in Rockland at a glance
Each month’s typical high and low, and what it brings.
What stands out about Rockland’s climate
Compared with towns across the U.S., with Rockland’s place in Idaho beside it.
What a year in Rockland feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 125 frost-free days a year
In half of years the last 32° night comes by May 20 and the first by September 26. Frost and day counts come from NOAA’s station at Massacre Rocks Sp, ID, 9 miles from the town’s center, 470 ft lower.
The 2023 USDA map puts Rockland’s center in zone 6a: the coldest night of a typical winter, averaged over 1991–2020, reaches about −8°. 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 35 inches of snow a winter
Snow, measured at American Falls 6 Ne, ID, falls mostly in January. Precipitation (rain plus melted snow) adds up to 15 inches a year; May is the wettest month and July the driest. Rain or snow falls on about 79 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in Rockland
94% 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 Massacre Rocks Sp, ID.
Living with Rockland’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
125 frost-free days in zone 6a. The last frost comes by May 20 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 26.
Months with highs of 62–84° and lows of 40° or more: June and September.
Parks & trails →Of the yearly building losses FEMA expects in Rockland from natural hazards, wildfire is the largest share (45%); heat waves, cold waves, winter storms and ice storms together are 29%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Rockland and similar climates
TownRatings has no climate map of the towns around Rockland yet.
Climates most like Rockland’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 |
|---|---|---|---|---|
| Rockland, ID | 16° | 88° | 15" | 35" |
| Lockwood, MT | 15° | 88° | 15" | 35" |
| Wellington, CO | 16° | 88° | 14" | 34" |
| Spring Creek, NV | 15° | 89° | 14" | 41" |
| Gallup, NM | 17° | 88° | 10" | 34" |
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 Rockland averaged 1.0° warmer than the 1900s. The biggest change is in January (+2.6°).
A smaller shift than in 80% 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 Rockland compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Rockland’s place among Idaho’s.
Rockland weather by month
Highs, lows and precipitation from NOAA’s grid at Rockland’s center; snow, wet days and snow on the ground from American Falls 6 Ne, ID. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 34° | 16° | 1.6" | 9.4" | 10 | 21 | 16° – 33° |
| February | 38° | 18° | 1.2" | 7.2" | 8 | 15 | 21° – 36° |
| March | 49° | 26° | 1.4" | 3.2" | 8 | 3 | 31° – 43° |
| April | 57° | 31° | 1.6" | 2.5" | 8 | 0 | 39° – 49° |
| May | 67° | 38° | 1.8" | 0.5" | 7 | 0 | 47° – 58° |
| June | 77° | 45° | 1.1" | 0.0" | 5 | 0 | 55° – 67° |
| July | 88° | 51° | 0.5" | 0.0" | 3 | 0 | 59° – 75° |
| August | 86° | 50° | 0.7" | 0.0" | 4 | 0 | 63° – 72° |
| September | 76° | 41° | 1.1" | 0.1" | 4 | 0 | 55° – 62° |
| October | 61° | 32° | 1.2" | 1.1" | 6 | 0 | 38° – 53° |
| November | 45° | 23° | 1.2" | 3.0" | 7 | 3 | 26° – 41° |
| December | 34° | 16° | 1.5" | 7.9" | 10 | 16 | 20° – 30° |
| Year | 59° | 32° | 14.8" | 34.9" | 79 | 59 |
How much a month can swing
A normal is an average. January swings the most: from 1991 to 2020 its average ranged from 16° to 33°. September is the most reliable, staying within 8°.
Where Rockland’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 Rockland’s center.
- Snow: American Falls 6 Ne, ID.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Massacre Rocks Sp, ID, 9 miles from the town’s center, 470 ft lower; 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 Rockland’s climate
What is the weather like in Rockland?
A typical July afternoon reaches 88°, a January night drops to 16°, and about 35 inches of snow falls in a normal winter. Colder January nights than 82% of U.S. towns; hotter July afternoons than 65% of U.S. towns.
How cold does it get in Rockland in winter?
January nights average 16°. About 160 nights a year reach 32° or below and 6 reach 0° or below. In the coldest January of the last 30 years the month averaged 16°.
How much snow does Rockland get?
About 35 inches in a normal winter at American Falls 6 Ne, ID, most of it in January, with snow on the ground about 59 days a year.
How hot does it get in Rockland?
July, with a typical high of 88° and a low of 51°. About 49 days a year reach 90° and 5 reach 100° (Massacre Rocks Sp, ID).
When is the first and last frost in Rockland?
In half of years the last spring frost (32°) comes by May 20 and the first fall frost by September 26, about 125 frost-free days, at Massacre Rocks Sp, ID.
What growing zone is Rockland in?
Zone 6a on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about −8°.
What is the best time of year to visit Rockland?
By one simple rule (highs of 62–84° and lows of 40° or more), June and September. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Rockland getting warmer?
Yes: 1991–2020 averaged 1.0° warmer than 1901–2000 on NOAA’s grid. A smaller shift than 80% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Rockland.
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.