Merrill, IA climate
Merrill has cold, snowy winters and warm summers. A typical July afternoon reaches 85°, a January night drops to 9°, and about 31 inches of snow falls in a normal winter.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in Merrill feels like
Winter
Spring
Summer
Fall
Merrill 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 | 28° | 9° | 0.7" | 7.8" | 4 | 9° – 33° |
| February | 33° | 14° | 0.8" | 7.5" | 5 | 12° – 34° |
| March | 46° | 25° | 1.5" | 4.6" | 6 | 28° – 52° |
| April | 60° | 36° | 2.9" | 1.9" | 8 | 38° – 55° |
| May | 72° | 48° | 4.2" | 0.1" | 10 | 54° – 66° |
| June | 82° | 59° | 4.6" | 0 | 10 | 66° – 75° |
| July | 85° | 62° | 3.4" | 0 | 7 | 67° – 80° |
| August | 82° | 60° | 3.6" | 0 | 8 | 66° – 76° |
| September | 76° | 51° | 3.1" | 0 | 7 | 57° – 69° |
| October | 62° | 38° | 2.4" | 0.4" | 6 | 43° – 55° |
| November | 46° | 25° | 1.3" | 2.6" | 4 | 25° – 46° |
| December | 32° | 14° | 1.0" | 6.0" | 4 | 9° – 29° |
| Year | 59° | 37° | 29.5" | 30.9" | 77 |
“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 Merrill
Merrill gets 30 inches of rain and melted snow a year. June is the wettest month and January the driest. Rain or snow falls on about 77 days a year.
About 157 frost-free days a year
In half of years the last 32° night comes by April 30 and the first one by October 4. That leaves about 157 frost-free days for gardens, shorter than 74% of U.S. towns.
Heating and cooling a home in Merrill
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Merrill, 91% of that work is heating and 9% 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 Merrill 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 Merrill averaged 1.1° warmer than the 1900s. The biggest change is in January (+2.4°). The shift is smaller than in 57% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Merrill’s spot on NOAA’s grid
How much a month can swing
A normal is an average, and real years wander around it. March swings the most: between 1991 and 2020 its average temperature ranged from 28° to 52°. June is the most reliable, staying within 9°.
Common questions about Merrill’s climate
What is the coldest month in Merrill?
January, with a typical high of 28° and a low of 9°.
What is the hottest month in Merrill?
July, with a typical high of 85° and a low of 62°. About 17 days a year reach 90°.
How much snow does Merrill get?
About 31 inches in a normal winter, most of it in January.
When is the first frost in Merrill?
In half of years the first 32° night comes by October 4, and the last spring frost by April 30.
What is the rainiest month in Merrill?
June, with 4.6 inches of rain and melted snow. The year totals 30 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Merrill itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Le Mars, IA (7 mi) away. Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000.