Keystone, WI climate
Keystone has cold, snowy winters and pleasant summers. A typical July afternoon reaches 79°, a January night drops to 3°, and about 74 inches of snow falls in a normal winter.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in Keystone feels like
Winter
Spring
Summer
Fall
Keystone 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 | 21° | 3° | 1.1" | 15.5" | 9 | -1° – 25° |
| February | 27° | 5° | 1.0" | 12.1" | 6 | 6° – 32° |
| March | 38° | 17° | 1.6" | 12.5" | 8 | 19° – 41° |
| April | 51° | 28° | 2.6" | 6.5" | 10 | 33° – 46° |
| May | 65° | 39° | 3.5" | 0.1" | 10 | 47° – 58° |
| June | 74° | 49° | 3.9" | 0 | 11 | 59° – 65° |
| July | 79° | 55° | 4.2" | 0 | 11 | 61° – 73° |
| August | 77° | 53° | 3.6" | 0 | 10 | 60° – 69° |
| September | 68° | 46° | 3.3" | 0 | 10 | 50° – 62° |
| October | 54° | 34° | 3.2" | 1.2" | 10 | 38° – 48° |
| November | 38° | 23° | 2.0" | 12.9" | 8 | 22° – 41° |
| December | 26° | 11° | 1.5" | 13.4" | 9 | 7° – 28° |
| Year | 52° | 30° | 31.4" | 74.2" | 112 |
“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 Keystone
Keystone gets 31 inches of rain and melted snow a year. July is the wettest month and February the driest. Rain or snow falls on about 112 days a year.
About 133 frost-free days a year
In half of years the last 32° night comes by May 20 and the first one by October 2. That leaves about 133 frost-free days for gardens, shorter than 93% of U.S. towns.
Heating and cooling a home in Keystone
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Keystone, 97% of that work is heating and 3% 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.
Keystone and its neighbors
Keystone borders 5 towns with climate data. January nights across them vary by 2.5°. Delta has the coldest January nights (2°) and Mason the hottest July afternoons (79°). Keystone’s January low is 3° and its July high 79°.
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value.
How Keystone 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 Keystone averaged 1.6° warmer than the 1900s. The biggest change is in January (+3.6°). The shift is larger than in 77% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Keystone’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 6° to 32°. June is the most reliable, staying within 6°.
Common questions about Keystone’s climate
What is the coldest month in Keystone?
January, with a typical high of 21° and a low of 3°.
What is the hottest month in Keystone?
July, with a typical high of 79° and a low of 55°. About 5 days a year reach 90°.
How much snow does Keystone get?
About 74 inches in a normal winter, most of it in January.
When is the first frost in Keystone?
In half of years the first 32° night comes by October 2, and the last spring frost by May 20.
What is the rainiest month in Keystone?
July, with 4.2 inches of rain and melted snow. The year totals 31 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Keystone itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Drummond, WI (14 mi, snow) and Ashland 3s, WI (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.