Deep River, IA climate
Deep River has cold winters and warm summers. A typical July afternoon reaches 84°, a January night drops to 12°, and about 30 inches of snow falls in a normal winter.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in Deep River feels like
Winter
Spring
Summer
Fall
Deep River 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 | 29° | 12° | 1.1" | 8.2" | 6 | 20 | 12° – 33° |
| February | 34° | 17° | 1.4" | 8.9" | 7 | 17 | 14° – 38° |
| March | 48° | 27° | 2.2" | 3.9" | 8 | 7 | 30° – 52° |
| April | 61° | 38° | 3.8" | 0.6" | 10 | 0 | 40° – 56° |
| May | 71° | 49° | 4.9" | 0 | 11 | 0 | 54° – 68° |
| June | 81° | 59° | 5.5" | 0 | 11 | 0 | 67° – 74° |
| July | 84° | 63° | 4.2" | 0 | 8 | 0 | 68° – 80° |
| August | 82° | 60° | 4.3" | 0 | 9 | 0 | 66° – 77° |
| September | 76° | 52° | 3.6" | 0 | 7 | 0 | 58° – 69° |
| October | 63° | 40° | 2.9" | 0.9" | 8 | 0 | 46° – 57° |
| November | 48° | 29° | 2.2" | 1.1" | 7 | 2 | 30° – 49° |
| December | 35° | 18° | 1.5" | 6.2" | 7 | 12 | 11° – 36° |
| Year | 59° | 39° | 37.4" | 29.8" | 100 | 59 |
“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 Deep River
Deep River gets 37 inches of rain and melted snow a year. June is the wettest month and January the driest. Rain or snow falls on about 100 days a year. Snow covers the ground about 59 days of the year.
About 172 frost-free days a year
In half of years the last 32° night comes by April 24 and the first one by October 15. That leaves about 172 frost-free days for gardens, shorter than 58% of U.S. towns.
Heating and cooling a home in Deep River
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Deep River, 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 Deep River 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 Deep River averaged 0.8° warmer than the 1900s. The biggest change is in December (+2.4°). The shift is smaller than in 86% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Deep River’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 11° to 36°. June is the most reliable, staying within 7°.
Common questions about Deep River’s climate
What is the coldest month in Deep River?
January, with a typical high of 29° and a low of 12°.
What is the hottest month in Deep River?
July, with a typical high of 84° and a low of 63°. About 16 days a year reach 90°.
How much snow does Deep River get?
About 30 inches in a normal winter, most of it in February.
When is the first frost in Deep River?
In half of years the first 32° night comes by October 15, and the last spring frost by April 24.
What is the rainiest month in Deep River?
June, with 5.5 inches of rain and melted snow. The year totals 37 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Deep River itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Brooklyn, IA (11 mi, snow) and Sigourney, IA (18 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.