Boulder, NV climate
Boulder has warm winters and scorching summers, with very little rain. A typical July afternoon reaches 106°, a January night drops to 41°, and snow is almost unheard of.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in Boulder feels like
Winter
Spring
Summer
Fall
Boulder 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 | 60° | 41° | 0.6" | 0 | 4 | 0 | 46° – 56° |
| February | 64° | 44° | 0.8" | 0 | 4 | 0 | 47° – 61° |
| March | 73° | 50° | 0.4" | 0 | 4 | 0 | 54° – 67° |
| April | 80° | 56° | 0.2" | 0 | 2 | 0 | 62° – 73° |
| May | 90° | 65° | 0.1" | 0 | 1 | 0 | 70° – 83° |
| June | 101° | 74° | 0.1" | 0 | 1 | 0 | 82° – 92° |
| July | 106° | 80° | 0.4" | 0 | 2 | 0 | 89° – 96° |
| August | 104° | 79° | 0.4" | 0 | 3 | 0 | 88° – 95° |
| September | 97° | 71° | 0.3" | 0 | 2 | 0 | 81° – 87° |
| October | 83° | 59° | 0.4" | 0 | 2 | 0 | 67° – 77° |
| November | 69° | 48° | 0.3" | 0 | 2 | 0 | 51° – 64° |
| December | 59° | 40° | 0.5" | 0 | 2 | 0 | 45° – 54° |
| Year | 82° | 59° | 4.3" | 0.0" | 27 | 0 |
“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
Boulder gets 4 inches of rain and melted snow a year. February is the wettest month and June the driest. Rain or snow falls on about 27 days a year.
About 328 frost-free days a year
In half of years the last 32° night comes by January 21 and the first one by December 17. That leaves about 328 frost-free days for gardens, longer than 96% of U.S. towns.
Heating and cooling a home in Boulder
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Boulder, 28% of that work is heating and 72% is cooling, so air conditioning is the bigger bill.
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.
Boulder and its neighbors
Boulder borders 1 town with climate data. January nights across them vary by 1.1°. Henderson has both the coldest January nights (40°) and the hottest July afternoons (105°). Boulder’s January low is 41° and its July high 106°.
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value.
How Boulder 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 averaged 1.8° warmer than the 1900s. The biggest change is in January (+2.7°). The shift is larger than in 85% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Boulder’s spot on NOAA’s grid
How much a month can swing
A normal is an average, and real years wander around it. February swings the most: between 1991 and 2020 its average temperature ranged from 47° to 61°. September is the most reliable, staying within 6°.
Common questions about Boulder’s climate
What is the coldest month in Boulder?
December, with a typical high of 59° and a low of 40°.
What is the hottest month in Boulder?
July, with a typical high of 106° and a low of 80°. About 147 days a year reach 90°.
How much snow does Boulder get?
Almost none. A normal year brings 0.0 inches.
When is the first frost in Boulder?
In half of years the first 32° night comes by December 17, and the last spring frost by January 21.
What is the rainiest month in Boulder?
February, with 0.8 inches of rain and melted snow. The year totals 4 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Boulder itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Boulder City, NV (10 mi, snow) and Alan Bible Visitor Ctr, NV (13 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.