Aspen Hill, Maryland climate: NOAA's gridded normals for the city, beside the nearest station records
NOAA's gridded 1991-2020 normals put Aspen Hill's center at January lows of 25°F and July highs of 87°F, a yearly mean of 55.2°F and 45.3 inches of precipitation. No NOAA station keeps a record under the city's name. The nearest station record, Rockville (4 miles W, 440 ft), has January lows of 27°F and July highs of 87°F.
53,752 people (Census Bureau 2024). Distances and directions are from the city's center.
- Jan 42° 25°
- Feb 45° 27°
- Mar 54° 33°
- Apr 65° 43°
- May 74° 53°
- Jun 82° 62°
- Jul 87° 67°
- Aug 84° 65°
- Sep 78° 58°
- Oct 67° 46°
- Nov 56° 36°
- Dec 46° 29°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
The months above are NOAA's gridded normals at Aspen Hill's center.
What is each month like in Aspen Hill?
NOAA's grid estimates the normals every 5 km or so from the stations around each point, terrain included. It smooths between stations, so night lows at the heart of a large city can run warmer than the grid shows: at five big-city airports we compared, the grid's highs were within about 1°F of the station and its lows 1-6°F cooler. The nearest record's high and low are beside each month.
| Month | High | Low | Mean | Precip. | Rockville high | Rockville low |
|---|---|---|---|---|---|---|
| January | 42°F | 25°F | 33.6°F | 3.05 | 42°F | 27°F |
| February | 45°F | 27°F | 36.0°F | 2.67 | 45°F | 28°F |
| March | 54°F | 33°F | 43.5°F | 3.83 | 54°F | 36°F |
| April | 65°F | 43°F | 54.3°F | 3.50 | 66°F | 46°F |
| May | 74°F | 53°F | 63.3°F | 4.36 | 74°F | 55°F |
| June | 82°F | 62°F | 71.9°F | 4.33 | 82°F | 64°F |
| July | 87°F | 67°F | 76.6°F | 4.52 | 87°F | 69°F |
| August | 84°F | 65°F | 74.5°F | 3.89 | 85°F | 67°F |
| September | 78°F | 58°F | 68.0°F | 4.33 | 78°F | 60°F |
| October | 67°F | 46°F | 56.7°F | 3.90 | 66°F | 48°F |
| November | 56°F | 36°F | 45.9°F | 3.19 | 56°F | 38°F |
| December | 46°F | 29°F | 37.7°F | 3.71 | 46°F | 31°F |
In metric: a yearly mean of 12.9°C, January lows of −4°C, July highs of 30°C and 1,150 mm of precipitation a year.
Source: NOAA NCEI U.S. Monthly Gridded Climate Normals 1991-2020 (nClimGrid, accession 0245564); NOAA NCEI 1991-2020 station normals. The grid cell holding the city's Census center point.
What do the station records around Aspen Hill say?
Each row is a NOAA station's own 1991-2020 normals, with the snow and frost dates the grid does not give. A record downhill or nearer the coast than the city can run warmer, one uphill cooler: compare the elevations.
| Record | Where | Elevation | Year | Jan low | Jul high | Precip. | Snow | Last frost |
|---|---|---|---|---|---|---|---|---|
| Rockville1 mi NE | 4 mi W | 440 ft | 56.2°F | 27°F | 87°F | 41.3 | – | April 1 |
| Beltsville | 9 mi SE | 145 ft | 55.9°F | 25°F | 87°F | 44.0 | 16 | April 10 |
| Laurel3 mi W | 10 mi E | 400 ft | 57.1°F | 26°F | 89°F | 47.5 | – | April 5 |
Source: NOAA NCEI 1991-2020 U.S. Climate Normals; place center and population: Census Bureau 2024. Last frost: the median last spring date of 32°F.
How much snow, how late a frost, what zone and how much sun in Aspen Hill?
NOAA's grid gives no snow, frost dates or records, so these come from the nearest station record, Rockville (4 miles W, 440 ft). NOAA publishes no snowfall normal for it; the nearest record that has one, Beltsville (9 miles SE), gets 16 inches a year. The last spring frost (32°F) comes after April 1 in half of years and the first autumn frost before November 6. Its record high is 104°F (1918) and its record low −13°F (1985) (kept since 1907).
The USDA's 2023 Plant Hardiness Zone Map puts Aspen Hill in zone 7b across its 2 ZIP code areas.
Over a year 73% of the sunlight that would reach the ground under clear skies gets through the clouds in the area (4.0 kWh per square metre a day, NASA POWER 2001-2020); July is the sunniest month (79%) and January the cloudiest (65%).
Rockville's page has its months, frost probabilities, records by month and recent years. NOAA's grid has monthly figures only, so there are no day-by-day month pages for Aspen Hill; the nearest record's month pages have them.
Source: NOAA NCEI 1991-2020 normals, station USC00187705; records: ACIS; USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026; sunshine: NASA POWER.
How does the climate vary across Aspen Hill, ZIP code by ZIP code?
2 ZIP code areas lie wholly or partly in Aspen Hill. On NOAA's grid 20853 is the warmest (55.2°F a year) and 20906 the coolest (55.2°F), so the city is nearly uniform. Each row also names the nearest station record and its frost dates.
Source: Census Bureau 2020 ZCTA-to-place relationship file and ZCTA centers; NOAA NCEI gridded and station normals, 1991-2020. A ZIP area counts when at least a tenth of its land (and 0.5 km²) is in the city; its figures are the grid cell at its center; frost dates are the nearest record's medians of 32°F.