Lewis, CO climate
Lewis has chilly, snowy winters and warm summers, with very little rain. A typical July afternoon reaches 87°, a January night drops to 16°, and about 70 inches of snow falls in a normal winter.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in Lewis feels like
Winter
Spring
Summer
Fall
Lewis 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 | 40° | 16° | 1.6" | 15.6" | 8 | 20° – 35° |
| February | 44° | 20° | 1.6" | 15.4" | 8 | 27° – 39° |
| March | 52° | 26° | 1.2" | 9.7" | 8 | 35° – 44° |
| April | 59° | 32° | 1.0" | 6.5" | 7 | 41° – 50° |
| May | 69° | 40° | 1.2" | 0.3" | 7 | 49° – 58° |
| June | 81° | 48° | 0.5" | 0 | 4 | 60° – 69° |
| July | 87° | 55° | 1.4" | 0 | 9 | 66° – 74° |
| August | 83° | 53° | 1.7" | 0 | 12 | 66° – 72° |
| September | 76° | 45° | 1.8" | 0 | 9 | 55° – 63° |
| October | 63° | 35° | 1.5" | 2.5" | 8 | 44° – 53° |
| November | 50° | 24° | 1.2" | 9.8" | 7 | 31° – 44° |
| December | 40° | 17° | 1.3" | 9.9" | 6 | 22° – 34° |
| Year | 62° | 34° | 15.8" | 69.7" | 91 |
“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 Lewis
Lewis gets 16 inches of rain and melted snow a year. September is the wettest month and June the driest. Rain or snow falls on about 91 days a year.
About 147 frost-free days a year
In half of years the last 32° night comes by May 15 and the first one by October 8. That leaves about 147 frost-free days for gardens, shorter than 83% of U.S. towns.
Heating and cooling a home in Lewis
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Lewis, 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 Lewis 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 Lewis averaged 1.9° warmer than the 1900s. The biggest change is in March (+3.1°). The shift is larger than in 91% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Lewis’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 35°. August is the most reliable, staying within 7°.
Common questions about Lewis’s climate
What is the coldest month in Lewis?
January, with a typical high of 40° and a low of 16°.
What is the hottest month in Lewis?
July, with a typical high of 87° and a low of 55°. About 14 days a year reach 90°.
How much snow does Lewis get?
About 70 inches in a normal winter, most of it in January.
When is the first frost in Lewis?
In half of years the first 32° night comes by October 8, and the last spring frost by May 15.
What is the rainiest month in Lewis?
September, with 1.8 inches of rain and melted snow. The year totals 16 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Lewis itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Dolores, CO (9 mi, snow) and Yellow Jacket 4ne, CO (4 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.