Ashton-Sandy Spring, MD climate
Ashton-Sandy Spring has chilly winters and warm summers. A typical July afternoon reaches 87°, a January night drops to 25°, and about 16 inches of snow falls in a normal winter.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in Ashton-Sandy Spring feels like
Winter
Spring
Summer
Fall
Ashton-Sandy Spring 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 | 42° | 25° | 3.1" | 5.7" | 10 | 5 | 25° – 41° |
| February | 45° | 27° | 2.7" | 5.0" | 9 | 6 | 25° – 43° |
| March | 54° | 33° | 3.9" | 2.5" | 10 | 2 | 38° – 53° |
| April | 65° | 43° | 3.6" | 0.1" | 11 | 0 | 51° – 60° |
| May | 74° | 52° | 4.4" | 0 | 11 | 0 | 59° – 70° |
| June | 82° | 61° | 4.4" | 0 | 10 | 0 | 68° – 76° |
| July | 87° | 66° | 4.5" | 0 | 10 | 0 | 71° – 80° |
| August | 84° | 64° | 4.1" | 0 | 9 | 0 | 70° – 77° |
| September | 78° | 58° | 4.4" | 0 | 9 | 0 | 65° – 72° |
| October | 67° | 46° | 4.0" | 0 | 9 | 0 | 53° – 63° |
| November | 56° | 36° | 3.3" | 0.2" | 8 | 0 | 40° – 51° |
| December | 46° | 29° | 3.8" | 2.3" | 10 | 2 | 28° – 48° |
| Year | 65° | 45° | 46.3" | 15.8" | 116 | 14 |
“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 Ashton-Sandy Spring
Ashton-Sandy Spring gets 46 inches of rain and melted snow a year. July is the wettest month and February the driest. Rain or snow falls on about 116 days a year. Snow covers the ground about 14 days of the year.
About 202 frost-free days a year
In half of years the last 32° night comes by April 10 and the first one by November 1. That leaves about 202 frost-free days for gardens, longer than 73% of U.S. towns.
Heating and cooling a home in Ashton-Sandy Spring
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Ashton-Sandy Spring, 78% of that work is heating and 22% is cooling.
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.
Ashton-Sandy Spring and its neighbors
Ashton-Sandy Spring borders 4 towns with climate data. January nights across them vary by 0.2°. Olney has the coldest January nights (25°) and Burtonsville the hottest July afternoons (87°). Ashton-Sandy Spring’s January low is 25° and its July high 87°.
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value.
How Ashton-Sandy Spring 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 Ashton-Sandy Spring averaged 1.8° warmer than the 1900s. The biggest change is in December (+2.9°). The shift is larger than in 85% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Ashton-Sandy Spring’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 28° to 48°. September is the most reliable, staying within 7°.
Common questions about Ashton-Sandy Spring’s climate
What is the coldest month in Ashton-Sandy Spring?
January, with a typical high of 42° and a low of 25°.
What is the hottest month in Ashton-Sandy Spring?
July, with a typical high of 87° and a low of 66°. About 30 days a year reach 90°.
How much snow does Ashton-Sandy Spring get?
About 16 inches in a normal winter, most of it in January.
When is the first frost in Ashton-Sandy Spring?
In half of years the first 32° night comes by November 1, and the last spring frost by April 10.
What is the rainiest month in Ashton-Sandy Spring?
July, with 4.5 inches of rain and melted snow. The year totals 46 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Ashton-Sandy Spring itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Beltsville, MD (9 mi) away. Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000.