Monroe, IA climate
Monroe has cold winters and warm summers. A typical July afternoon reaches 85°, a January night drops to 13°, and about 29 inches of snow falls in a normal winter.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in Monroe feels like
Winter
Spring
Summer
Fall
Monroe 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 | 30° | 13° | 1.0" | 9.2" | 6 | 13° – 34° |
| February | 35° | 18° | 1.3" | 6.0" | 6 | 15° – 37° |
| March | 48° | 28° | 2.0" | 4.5" | 8 | 30° – 53° |
| April | 61° | 39° | 3.9" | 0.8" | 10 | 41° – 57° |
| May | 72° | 50° | 4.8" | 0 | 12 | 56° – 69° |
| June | 81° | 61° | 5.4" | 0 | 11 | 68° – 74° |
| July | 85° | 65° | 4.3" | 0 | 8 | 69° – 81° |
| August | 83° | 62° | 4.1" | 0 | 9 | 67° – 78° |
| September | 76° | 54° | 3.6" | 0 | 7 | 59° – 70° |
| October | 63° | 42° | 2.7" | 0.3" | 8 | 47° – 58° |
| November | 48° | 30° | 2.0" | 1.6" | 6 | 31° – 50° |
| December | 35° | 19° | 1.4" | 6.3" | 7 | 12° – 36° |
| Year | 60° | 40° | 36.4" | 28.7" | 98 |
“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 Monroe
Monroe gets 36 inches of rain and melted snow a year. June is the wettest month and January the driest. Rain or snow falls on about 98 days a year.
About 180 frost-free days a year
In half of years the last 32° night comes by April 20 and the first one by October 19. That leaves about 180 frost-free days for gardens, longer than 53% of U.S. towns.
Heating and cooling a home in Monroe
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Monroe, 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 Monroe 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 Monroe averaged 0.6° warmer than the 1900s. The biggest change is in December (+2.1°). The shift is smaller than in 94% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Monroe’s spot on NOAA’s grid
How much a month can swing
A normal is an average, and real years wander around it. December swings the most: between 1991 and 2020 its average temperature ranged from 12° to 36°. June is the most reliable, staying within 6°.
Common questions about Monroe’s climate
What is the coldest month in Monroe?
January, with a typical high of 30° and a low of 13°.
What is the hottest month in Monroe?
July, with a typical high of 85° and a low of 65°. About 20 days a year reach 90°.
How much snow does Monroe get?
About 29 inches in a normal winter, most of it in January.
When is the first frost in Monroe?
In half of years the first 32° night comes by October 19, and the last spring frost by April 20.
What is the rainiest month in Monroe?
June, with 5.4 inches of rain and melted snow. The year totals 36 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Monroe itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Newton, IA (14 mi, snow) and Knoxville, IA (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.