Castle Valley, UT climate
Castle Valley has chilly winters and hot summers, with very little rain. A typical July afternoon reaches 96°, a January night drops to 21°, and about 15 inches of snow falls in a normal winter.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in Castle Valley feels like
Winter
Spring
Summer
Fall
Castle Valley weather by month
Average highs, lows, rain and snow for every month, from NOAA’s 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | 30-yr range |
|---|---|---|---|---|---|---|
| January | 41° | 21° | 0.7" | 3.6" | 4 | 20° – 39° |
| February | 49° | 26° | 0.7" | 1.6" | 6 | 32° – 45° |
| March | 60° | 34° | 0.8" | 1.0" | 4 | 42° – 52° |
| April | 68° | 40° | 0.9" | 1.0" | 5 | 49° – 59° |
| May | 78° | 49° | 1.0" | 0 | 5 | 58° – 68° |
| June | 90° | 58° | 0.5" | 0 | 2 | 69° – 79° |
| July | 96° | 65° | 0.9" | 0 | 3 | 76° – 84° |
| August | 93° | 63° | 0.9" | 0 | 4 | 74° – 83° |
| September | 84° | 53° | 0.9" | 0 | 4 | 63° – 73° |
| October | 70° | 41° | 1.2" | 0 | 4 | 50° – 60° |
| November | 54° | 30° | 0.8" | 2.2" | 4 | 35° – 48° |
| December | 41° | 21° | 0.7" | 5.7" | 4 | 23° – 37° |
| Year | 69° | 42° | 10.0" | 15.1" | 49 |
“Wet days” have at least 0.01" of rain or melted snow. “Snow on ground” counts days with 1" or more. The 30-year range is the coldest and warmest that month’s average temperature got between 1991 and 2020.
Rain and snow in Castle Valley
Castle Valley gets 10 inches of rain and melted snow a year. October is the wettest month and June the driest. Rain or snow falls on about 49 days a year.
About 185 frost-free days a year
In half of years the last 32° night comes by April 17 and the first one by October 23. That leaves about 185 frost-free days for gardens, longer than 58% of U.S. towns.
Heating and cooling a home in Castle Valley
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Castle Valley, 77% of that work is heating and 23% is cooling.
Degree days measure how far each day’s average temperature falls below or rises above 65°, added up over a year. Source: NOAA station normals.
How Castle Valley compares
Compared with every U.S. town and city on TownTapestry, each counted once.
Warmer than it used to be
The last 30 years in Castle Valley averaged 2.4° warmer than the 1900s. The biggest change is in January (+3.6°). The shift is larger than in 99% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Castle Valley’s spot on NOAA’s grid
How much a month can swing
A normal is an average, and real years wander around it. January swings the most: between 1991 and 2020 its average temperature ranged from 20° to 39°. July is the most reliable, staying within 8°.
Common questions about Castle Valley’s climate
What is the coldest month in Castle Valley?
January, with a typical high of 41° and a low of 21°.
What is the hottest month in Castle Valley?
July, with a typical high of 96° and a low of 65°. About 73 days a year reach 90°.
How much snow does Castle Valley get?
About 15 inches in a normal winter, most of it in December.
When is the first frost in Castle Valley?
In half of years the first 32° night comes by October 23, and the last spring frost by April 17.
What is the rainiest month in Castle Valley?
October, with 1.2 inches of rain and melted snow. The year totals 10 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Castle Valley itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Castle Valley, UT (1 mi) away. Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000.