Charleston has cold, snowy winters and pleasant summers
A typical July afternoon reaches 80°, a January night drops to 15°, and about 54 inches of snow falls in a normal winter.
A year in Charleston at a glance
Each month’s typical high and low, and what it brings.
What stands out about Charleston’s climate
Read from where Charleston sits among Pennsylvania’s towns. The page puts what stands out first.
About 148 frost-free days a year
In half of years the last 32° night comes by May 10 and the first by October 5.
Freezing nights by month
Average nights at or below 32°
90° days by month
Average days at 90° or more
What a year in Charleston feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
Living with Charleston’s climate
What the numbers mean for a garden, a driveway, a furnace and a free afternoon.
148 frost-free days. The last frost comes by May 10 in half of years, so many gardeners wait a week or two past that to set out tomatoes. The first fall frost comes by Oct 5.
About 54" a winter over 21 days with an inch or more, most in January. Snow covers the ground about 71 days a year.
Months averaging under 55° run from October through April. Heating is 96% of the year’s heating-and-cooling load.
About 2 days a year reach 90°, and July afternoons average 80°.
The nicest months are May, June, July, August and September. 6.9 miles of trails are waiting.
Parks & trails →Normals are averages. Ice storms, nor’easters, floods and heat waves are on the natural hazards page.
Natural hazards →54 inches of snow, 41 of rain and melt
September is the wettest month and February the driest. Rain or snow falls on about 113 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Warmer than it used to be
The last 30 years in Charleston averaged 0.9° warmer than the 1900s. The biggest change is in December (+2.5°).
A smaller shift than in 77% of U.S. towns.
Change by month
Charleston and its neighbors
Delmar has the coldest January nights next door (15°) and Middlebury the hottest July afternoons (81°). Tap a town to see its climate.
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value. Snow and frost-free days come from the nearest weather station, so neighbors often share them.
How Charleston compares
Against every U.S. town on TownTapestry, each counted once, with its place in Pennsylvania.
Charleston 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° | 15° | 2.8" | 12.4" | 10 | 19 | 13° – 31° |
| February | 34° | 16° | 2.2" | 11.5" | 8 | 18 | 12° – 33° |
| March | 43° | 23° | 3.1" | 11.9" | 9 | 13 | 26° – 45° |
| April | 56° | 32° | 3.5" | 2.8" | 10 | 2 | 39° – 50° |
| May | 68° | 43° | 3.7" | 0.1" | 10 | 0 | 49° – 61° |
| June | 76° | 52° | 4.0" | 0 | 11 | 0 | 60° – 67° |
| July | 80° | 56° | 4.1" | 0 | 10 | 0 | 63° – 72° |
| August | 78° | 54° | 3.7" | 0 | 9 | 0 | 63° – 70° |
| September | 71° | 48° | 4.3" | 0 | 9 | 0 | 56° – 64° |
| October | 59° | 37° | 3.8" | 0.7" | 9 | 0 | 43° – 54° |
| November | 46° | 29° | 3.0" | 3.8" | 8 | 5 | 33° – 43° |
| December | 36° | 21° | 3.0" | 10.8" | 10 | 14 | 19° – 39° |
| Year | 56° | 35° | 41.2" | 54.0" | 113 | 71 |
Heating and cooling a home in Charleston
96% of the work is heating, so the furnace matters far more than the air conditioner.
Degree days add up how far each day’s average falls below (heating) or rises above (cooling) 65° over a year. Source: NOAA station normals.
How much a month can swing
A normal is an average. February swings the most: from 1991 to 2020 its average ranged from 12° to 33°. June is the most reliable, staying within 7°.
Common questions about Charleston’s climate
What is the coldest month in Charleston?
January, with a typical high of 31° and a low of 15°.
What is the hottest month in Charleston?
July, with a typical high of 80° and a low of 56°. About 2 days a year reach 90°.
How much snow does Charleston get?
About 54 inches in a normal winter, most of it in January.
When is the first frost in Charleston?
In half of years the first 32° night comes by October 5, and the last spring frost by May 10.
What is the rainiest month in Charleston?
September, with 4.3 inches of rain and melted snow. The year totals 41 inches.
Neighbors talk weather
Gardens, snow, and the best days of the year in Charleston.
Your answer becomes a post in Town Square.
Temperatures and rainfall come from NOAA’s gridded climate normals for Charleston itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Covington 2 Wsw, PA (6 mi, snow) and Wellsboro 4 Sw, PA (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. Today’s forecast: National Weather Service.