Bar Nunn, WY climate
Bar Nunn has chilly, snowy winters and warm summers, with very little rain. A typical July afternoon reaches 88°, a January night drops to 15°, and about 72 inches of snow falls in a normal winter.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in Bar Nunn feels like
Winter
Spring
Summer
Fall
Bar Nunn 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 | 37° | 15° | 0.5" | 9.0" | 6 | 17 | 20° – 32° |
| February | 38° | 16° | 0.5" | 10.9" | 7 | 12 | 19° – 35° |
| March | 49° | 24° | 0.8" | 10.3" | 8 | 6 | 28° – 44° |
| April | 57° | 30° | 1.5" | 10.5" | 10 | 3 | 37° – 49° |
| May | 67° | 39° | 2.3" | 2.6" | 11 | 1 | 47° – 59° |
| June | 79° | 47° | 1.4" | 0.1" | 9 | 0 | 56° – 68° |
| July | 88° | 55° | 1.1" | 0 | 7 | 0 | 64° – 75° |
| August | 86° | 52° | 0.8" | 0 | 6 | 0 | 64° – 73° |
| September | 75° | 43° | 1.0" | 1.5" | 7 | 0 | 54° – 65° |
| October | 60° | 32° | 1.2" | 7.0" | 8 | 2 | 38° – 53° |
| November | 46° | 23° | 0.6" | 8.9" | 6 | 7 | 22° – 43° |
| December | 36° | 15° | 0.5" | 11.0" | 7 | 16 | 17° – 30° |
| Year | 60° | 32° | 12.2" | 71.8" | 91 | 64 |
“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 Bar Nunn
Bar Nunn gets 12 inches of rain and melted snow a year. May is the wettest month and January the driest. Rain or snow falls on about 91 days a year. Snow covers the ground about 64 days of the year.
About 117 frost-free days a year
In half of years the last 32° night comes by May 26 and the first one by September 22. That leaves about 117 frost-free days for gardens, shorter than 98% of U.S. towns.
Heating and cooling a home in Bar Nunn
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Bar Nunn, 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 Bar Nunn 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 Bar Nunn averaged 1.6° warmer than the 1900s. The biggest change is in March (+4.0°). The shift is larger than in 78% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Bar Nunn’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 22° to 43°. August is the most reliable, staying within 9°.
Common questions about Bar Nunn’s climate
What is the coldest month in Bar Nunn?
December, with a typical high of 36° and a low of 15°.
What is the hottest month in Bar Nunn?
July, with a typical high of 88° and a low of 55°. About 38 days a year reach 90°.
How much snow does Bar Nunn get?
About 72 inches in a normal winter, most of it in December.
When is the first frost in Bar Nunn?
In half of years the first 32° night comes by September 22, and the last spring frost by May 26.
What is the rainiest month in Bar Nunn?
May, with 2.3 inches of rain and melted snow. The year totals 12 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Bar Nunn itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Casper Natrona Co Airport, WY (6 mi) away. Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000.