Photo: Ntsimp · Public domainDry weather: only 13 inches of rain and melted snow a year in Grantsville, less than in 94% of U.S. towns
High summer brings afternoon highs near 94°. Summer afternoons here are warmer than in 92% of U.S. towns. Compared with 1901–2000, the average now sits 1.4° higher. Seedlings are safe outdoors from about May 2, with the first autumn frost due around October 14.
A year in Grantsville at a glance
Each month’s typical high and low, and what it brings.
What stands out about Grantsville’s climate
Compared with towns across the U.S., with Grantsville’s place in Utah beside it.
What a year in Grantsville feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 164 frost-free days a year
In half of years the last 32° night comes by May 2 and the first by October 14. Frost and day counts come from NOAA’s station at Grantsville 2w, UT, 2.1 miles from the town’s center, 210 ft higher.
The 2023 USDA map puts Grantsville’s center in zone 7a: the coldest night of a typical winter, averaged over 1991–2020, reaches about 2°. 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 33 inches of snow a winter
Snow, measured at Grantsville 2w, UT, falls mostly in January, February and December. Precipitation (rain plus melted snow) adds up to 13 inches a year; May is the wettest month and July the driest. Rain or snow falls on about 76 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in Grantsville
85% 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 Grantsville 2w, UT.
Living with Grantsville’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
164 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 14.
Months with highs of 62–84° and lows of 40° or more: May, June and September. 35 miles of trails are waiting.
Parks & trails →Of the yearly building losses FEMA expects in Grantsville from natural hazards, wildfire is the largest share (58%); heat waves, cold waves, winter storms and ice storms together are 6%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Grantsville and its neighbors
Every town next door is within a degree of Grantsville in January and July, closer than the 5 km grid can tell apart. Tap a town to see its climate.
Climates most like Grantsville’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 |
|---|---|---|---|---|
| Grantsville, UT | 20° | 94° | 13" | 33" |
| La Junta, CO | 16° | 94° | 13" | 34" |
| Dalhart, TX | 21° | 92° | 16" | 20" |
| Winnemucca, NV | 21° | 93° | 8" | 22" |
| Garden City, ID | 24° | 93° | 13" | 18" |
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value. Snow and frost-free days come from the nearest weather station, so neighbors often share them.
Warmer than it used to be
The last 30 years in Grantsville averaged 1.4° warmer than the 1900s. The biggest change is in March (+2.7°).
A bigger shift than in 52% 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 Grantsville compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Grantsville’s place among Utah’s.
Grantsville weather by month
Highs, lows and precipitation from NOAA’s grid at Grantsville’s center; snow, wet days and snow on the ground from Grantsville 2w, UT. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 38° | 20° | 1.1" | 7.2" | 7 | 15 | 23° – 36° |
| February | 44° | 24° | 1.1" | 7.5" | 7 | 10 | 29° – 42° |
| March | 54° | 32° | 1.3" | 3.5" | 8 | 2 | 39° – 49° |
| April | 62° | 37° | 1.8" | 1.9" | 9 | 1 | 44° – 57° |
| May | 72° | 46° | 1.8" | 0.0" | 8 | 0 | 53° – 64° |
| June | 84° | 55° | 0.9" | 0.0" | 4 | 0 | 63° – 75° |
| July | 94° | 64° | 0.6" | 0.0" | 4 | 0 | 70° – 83° |
| August | 91° | 61° | 0.6" | 0.0" | 4 | 0 | 72° – 80° |
| September | 80° | 51° | 1.0" | 0.0" | 5 | 0 | 62° – 70° |
| October | 65° | 39° | 1.2" | 0.1" | 6 | 0 | 43° – 58° |
| November | 51° | 29° | 1.1" | 5.0" | 6 | 3 | 32° – 47° |
| December | 39° | 20° | 1.1" | 7.9" | 8 | 12 | 25° – 34° |
| Year | 65° | 40° | 13.4" | 33.1" | 76 | 41 |
How much a month can swing
A normal is an average. November swings the most: from 1991 to 2020 its average ranged from 32° to 47°. August is the most reliable, staying within 8°.
Where Grantsville’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 Grantsville’s center.
- Snow: Grantsville 2w, UT.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Grantsville 2w, UT, 2.1 miles from the town’s center, 210 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 Grantsville’s climate
What is the weather like in Grantsville?
A typical July afternoon reaches 94°, a January night drops to 20°, and about 33 inches of snow falls in a normal winter. Colder January nights than 59% of U.S. towns; hotter July afternoons than 92% of U.S. towns.
How cold does it get in Grantsville in winter?
January nights average 20°. About 142 nights a year reach 32° or below and 2 reach 0° or below. In the coldest January of the last 30 years the month averaged 23°.
How much snow does Grantsville get?
About 33 inches in a normal winter at Grantsville 2w, UT, most of it in January, February and December, with snow on the ground about 41 days a year.
How hot does it get in Grantsville?
July, with a typical high of 94° and a low of 64°. About 58 days a year reach 90° and 5 reach 100° (Grantsville 2w, UT).
When is the first and last frost in Grantsville?
In half of years the last spring frost (32°) comes by May 2 and the first fall frost by October 14, about 164 frost-free days, at Grantsville 2w, UT.
What growing zone is Grantsville in?
Zone 7a on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about 2°.
What is the best time of year to visit Grantsville?
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 Grantsville getting warmer?
Yes: 1991–2020 averaged 1.4° warmer than 1901–2000 on NOAA’s grid. A bigger shift than 52% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Grantsville.
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.