Trenton, IA climate
Trenton has cold, snowy winters and warm summers. A typical July afternoon reaches 85°, a January night drops to 14°, and about 34 inches of snow falls in a normal winter.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in Trenton feels like
Winter
Spring
Summer
Fall
Trenton 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 | 31° | 14° | 1.4" | 8.8" | 8 | 19 | 14° – 36° |
| February | 36° | 18° | 1.7" | 9.9" | 8 | 13 | 14° – 38° |
| March | 49° | 29° | 2.4" | 4.2" | 8 | 4 | 30° – 54° |
| April | 63° | 39° | 3.7" | 0.9" | 10 | 0 | 41° – 57° |
| May | 73° | 51° | 5.2" | 0 | 12 | 0 | 56° – 68° |
| June | 82° | 61° | 5.2" | 0 | 11 | 0 | 68° – 74° |
| July | 85° | 64° | 4.0" | 0 | 9 | 0 | 69° – 81° |
| August | 83° | 62° | 4.0" | 0 | 9 | 0 | 67° – 78° |
| September | 77° | 54° | 3.5" | 0 | 8 | 0 | 60° – 70° |
| October | 64° | 42° | 3.0" | 0.1" | 8 | 0 | 48° – 58° |
| November | 49° | 30° | 2.2" | 1.8" | 7 | 2 | 31° – 50° |
| December | 37° | 20° | 1.7" | 8.4" | 8 | 9 | 13° – 37° |
| Year | 61° | 40° | 38.1" | 34.1" | 105 | 48 |
“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 Trenton
Trenton gets 38 inches of rain and melted snow a year. May is the wettest month and January the driest. Rain or snow falls on about 105 days a year. Snow covers the ground about 48 days of the year.
About 163 frost-free days a year
In half of years the last 32° night comes by April 30 and the first one by October 10. That leaves about 163 frost-free days for gardens, shorter than 68% of U.S. towns.
Heating and cooling a home in Trenton
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Trenton, 89% of that work is heating and 11% 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 Trenton 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 Trenton averaged 0.4° warmer than the 1900s. The biggest change is in December (+1.8°). The shift is smaller than in 98% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Trenton’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 13° to 37°. June is the most reliable, staying within 6°.
Common questions about Trenton’s climate
What is the coldest month in Trenton?
January, with a typical high of 31° and a low of 14°.
What is the hottest month in Trenton?
July, with a typical high of 85° and a low of 64°. About 20 days a year reach 90°.
How much snow does Trenton get?
About 34 inches in a normal winter, most of it in February.
When is the first frost in Trenton?
In half of years the first 32° night comes by October 10, and the last spring frost by April 30.
What is the rainiest month in Trenton?
May, with 5.2 inches of rain and melted snow. The year totals 38 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Trenton itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Brighton, IA (12 mi, snow) and Mt Pleasant 1 Ssw, IA (9 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.