Delta, CO climate
Delta has chilly winters and hot summers, with very little rain. A typical July afternoon reaches 93°, a January night drops to 17°, and about 22 inches of snow falls in a normal winter.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in Delta feels like
Winter
Spring
Summer
Fall
Delta 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 | 41° | 17° | 0.6" | 4.7" | 5 | 16 | 20° – 36° |
| February | 48° | 23° | 0.5" | 3.9" | 5 | 6 | 31° – 41° |
| March | 59° | 31° | 0.7" | 2.2" | 5 | 2 | 40° – 50° |
| April | 66° | 36° | 0.7" | 0.6" | 6 | 0 | 46° – 57° |
| May | 76° | 45° | 0.8" | 0 | 6 | 0 | 55° – 65° |
| June | 88° | 53° | 0.5" | 0 | 3 | 0 | 65° – 75° |
| July | 93° | 59° | 1.0" | 0 | 6 | 0 | 72° – 81° |
| August | 90° | 58° | 1.0" | 0 | 8 | 0 | 70° – 79° |
| September | 82° | 49° | 1.3" | 0 | 7 | 0 | 60° – 69° |
| October | 68° | 37° | 1.0" | 0.5" | 6 | 1 | 47° – 58° |
| November | 53° | 27° | 0.6" | 2.7" | 4 | 2 | 33° – 48° |
| December | 41° | 18° | 0.5" | 6.9" | 5 | 11 | 24° – 36° |
| Year | 67° | 38° | 9.0" | 21.5" | 65 | 36 |
“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 Delta
Delta gets 9 inches of rain and melted snow a year. September is the wettest month and June the driest. Rain or snow falls on about 65 days a year. Snow covers the ground about 36 days of the year.
About 159 frost-free days a year
In half of years the last 32° night comes by May 1 and the first one by October 7. That leaves about 159 frost-free days for gardens, shorter than 72% of U.S. towns.
Heating and cooling a home in Delta
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Delta, 87% of that work is heating and 13% 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 Delta 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 Delta averaged 2.4° warmer than the 1900s. The biggest change is in January (+4.3°). The shift is larger than in 100% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Delta’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 36°. August is the most reliable, staying within 9°.
Common questions about Delta’s climate
What is the coldest month in Delta?
January, with a typical high of 41° and a low of 17°.
What is the hottest month in Delta?
July, with a typical high of 93° and a low of 59°. About 68 days a year reach 90°.
How much snow does Delta get?
About 22 inches in a normal winter, most of it in December.
When is the first frost in Delta?
In half of years the first 32° night comes by October 7, and the last spring frost by May 1.
What is the rainiest month in Delta?
September, with 1.3 inches of rain and melted snow. The year totals 9 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Delta itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Montrose #2, CO (22 mi, snow) and Delta 3e, CO (3 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.