Mercersville, MD climate
Mercersville has chilly winters and warm summers. A typical July afternoon reaches 88°, a January night drops to 23°.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in Mercersville feels like
Winter
Spring
Summer
Fall
Mercersville weather by month
Average highs, lows, rain and snow for every month, from NOAA’s 1991–2020 normals.
| Month | High | Low | Rain + melt | 30-yr range |
|---|---|---|---|---|
| January | 41° | 23° | 2.8" | 23° – 40° |
| February | 45° | 25° | 2.3" | 25° – 43° |
| March | 54° | 32° | 3.4" | 37° – 52° |
| April | 66° | 41° | 3.4" | 50° – 59° |
| May | 75° | 51° | 4.1" | 58° – 69° |
| June | 83° | 59° | 3.7" | 67° – 74° |
| July | 88° | 64° | 3.9" | 71° – 79° |
| August | 86° | 62° | 3.3" | 69° – 77° |
| September | 79° | 55° | 4.2" | 64° – 71° |
| October | 67° | 44° | 3.1" | 52° – 62° |
| November | 55° | 34° | 2.9" | 38° – 50° |
| December | 45° | 27° | 3.3" | 27° – 46° |
| Year | 65° | 43° | 40.3" |
“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 Mercersville
Mercersville gets 40 inches of rain and melted snow a year. September is the wettest month and February the driest.
About 183 frost-free days a year
In half of years the last 32° night comes by April 20 and the first one by October 22. That leaves about 183 frost-free days for gardens, longer than 56% of U.S. towns.
Heating and cooling a home in Mercersville
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Mercersville, 83% of that work is heating and 17% 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 Mercersville 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 Mercersville averaged 1.6° warmer than the 1900s. The biggest change is in December (+2.8°). The shift is larger than in 74% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Mercersville’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 27° to 46°. September is the most reliable, staying within 7°.
Common questions about Mercersville’s climate
What is the coldest month in Mercersville?
January, with a typical high of 41° and a low of 23°.
What is the hottest month in Mercersville?
July, with a typical high of 88° and a low of 64°. About 26 days a year reach 90°.
When is the first frost in Mercersville?
In half of years the first 32° night comes by October 22, and the last spring frost by April 20.
What is the rainiest month in Mercersville?
September, with 4.2 inches of rain and melted snow. The year totals 40 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Mercersville itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Martinsburg E Wv Rgnl Airport, WV (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.