Boulder Flats, WY climate
Boulder Flats has cold, snowy winters and warm summers, with very little rain. A typical July afternoon reaches 87°, a January night drops to 8°, and about 67 inches of snow falls in a normal winter.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in Boulder Flats feels like
Winter
Spring
Summer
Fall
Boulder Flats 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 | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 34° | 8° | 0.4" | 6.6" | 4 | 27 | 14° – 27° |
| February | 37° | 12° | 0.6" | 12.3" | 5 | 20 | 15° – 32° |
| March | 49° | 22° | 1.0" | 12.3" | 5 | 10 | 29° – 42° |
| April | 57° | 29° | 1.9" | 10.2" | 7 | 4 | 38° – 49° |
| May | 67° | 38° | 2.8" | 2.7" | 8 | 1 | 46° – 58° |
| June | 78° | 46° | 1.2" | 0 | 5 | 0 | 54° – 67° |
| July | 87° | 52° | 0.7" | 0 | 4 | 0 | 62° – 73° |
| August | 85° | 51° | 0.6" | 0 | 5 | 0 | 64° – 71° |
| September | 74° | 41° | 1.1" | 0.2" | 6 | 1 | 53° – 63° |
| October | 60° | 30° | 1.3" | 5.2" | 5 | 3 | 37° – 51° |
| November | 44° | 18° | 0.7" | 5.5" | 4 | 9 | 20° – 40° |
| December | 33° | 8° | 0.5" | 11.6" | 5 | 18 | 13° – 26° |
| Year | 59° | 30° | 12.8" | 66.6" | 63 | 93 |
“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 Boulder Flats
Boulder Flats gets 13 inches of rain and melted snow a year. May is the wettest month and January the driest. Rain or snow falls on about 63 days a year. Snow covers the ground about 93 days of the year.
About 131 frost-free days a year
In half of years the last 32° night comes by May 18 and the first one by September 27. That leaves about 131 frost-free days for gardens, shorter than 94% of U.S. towns.
Heating and cooling a home in Boulder Flats
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Boulder Flats, 94% of that work is heating and 6% is cooling, so the furnace matters far more than the air conditioner.
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 Boulder Flats 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 Boulder Flats averaged 1.4° warmer than the 1900s. The biggest change is in January (+3.5°). The shift is larger than in 66% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Boulder Flats’s spot on NOAA’s grid
How much a month can swing
A normal is an average, and real years wander around it. November swings the most: between 1991 and 2020 its average temperature ranged from 20° to 40°. August is the most reliable, staying within 7°.
Common questions about Boulder Flats’s climate
What is the coldest month in Boulder Flats?
December, with a typical high of 33° and a low of 8°.
What is the hottest month in Boulder Flats?
July, with a typical high of 87° and a low of 52°. About 30 days a year reach 90°.
How much snow does Boulder Flats get?
About 67 inches in a normal winter, most of it in February.
When is the first frost in Boulder Flats?
In half of years the first 32° night comes by September 27, and the last spring frost by May 18.
What is the rainiest month in Boulder Flats?
May, with 2.8 inches of rain and melted snow. The year totals 13 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Boulder Flats itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Lander 1n, WY (6 mi, snow) and Lander Hunt Fld Airport, WY (8 mi, frost, heat and degree days). Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000.