Araby · Photo: Preservation Maryland · CC BY-SA 2.0No extremes in Potomac Heights: its weather tracks the middle of U.S. towns
On a normal January night the air cools to about 27°. The seasons are far apart: from a winter night to a summer afternoon the average spans 62°. Summer afternoons here are warmer than in 71% of U.S. towns. The frost-free window for a garden runs roughly March 28 to November 8.
A year in Potomac Heights at a glance
Each month’s typical high and low, and what it brings.
What stands out about Potomac Heights’ climate
Compared with towns across the U.S., with Potomac Heights’ place in Maryland beside it.
What a year in Potomac Heights feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 226 frost-free days a year
In half of years the last 32° night comes by March 28 and the first by November 8. Frost and day counts come from NOAA’s station at Quantico Mcas, VA, 11 miles from the town’s center, at about the same height.
The 2023 USDA map puts Potomac Heights’ center in zone 7b: the coldest night of a typical winter, averaged over 1991–2020, reaches about 9°. Plant labels use the zone; frost dates tell you when to plant.
Freezing nights by month
Average nights at or below 32°
90° days by month
Average days at 90° or more
About 13 inches of snow a winter
Snow, measured at Franconia 1.3 Sse, VA, falls mostly in January. Precipitation (rain plus melted snow) adds up to 43 inches a year; July is the wettest month and February the driest. Rain or snow falls on about 116 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in Potomac Heights
73% of the work is heating. Months averaging under 55° run from November through March.
Degree days add up how far each day’s average falls below (heating) or rises above (cooling) 65° over a year. NOAA normals at Quantico Mcas, VA.
Living with Potomac Heights’ climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
226 frost-free days in zone 7b. The last frost comes by Mar 28 in half of years, so many gardeners wait a week or two past that to set out tomatoes. The first fall frost comes by Nov 8.
Months with highs of 62–84° and lows of 40° or more: April, May, September and October. 0.3 miles of trails are waiting.
Parks & trails →Of the yearly building losses FEMA expects in Potomac Heights from natural hazards, river flooding is the largest share (42%); heat waves, cold waves, winter storms and ice storms together are 18%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Potomac Heights and its neighbors
Every town next door is within a degree of Potomac Heights in January and July, closer than the 5 km grid can tell apart. Tap a town to see its climate.
Climates most like Potomac Heights’, farther away
TownRatings’ own comparison of NOAA 1991–2020 normals, not a NOAA product: places of 5,000+ at least 150 miles away, one per state, closest on January low, July high, precipitation and snow.
| Town | Jan. low | July high | Precip. | Snow |
|---|---|---|---|---|
| Potomac Heights, MD | 27° | 89° | 43" | 13" |
| Roanoke, VA | 27° | 88° | 44" | 15" |
| Chester, IL | 24° | 88° | 44" | 12" |
| Lemay, MO | 24° | 89° | 42" | 14" |
| Hurricane, WV | 25° | 87° | 44" | 11" |
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.
Warmer than it used to be
The last 30 years in Potomac Heights averaged 1.8° warmer than the 1900s. The biggest change is in December (+2.9°).
A bigger shift than in 81% of U.S. towns.
Change by month
The two periods overlap (1991–2000 is in both), which makes the gap a little smaller than it would be between separate periods.
How Potomac Heights compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Potomac Heights’ place among Maryland’s.
Potomac Heights weather by month
Highs, lows and precipitation from NOAA’s grid at Potomac Heights’ center; snow, wet days and snow on the ground from Franconia 1.3 Sse, VA. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 45° | 27° | 2.8" | 4.8" | 10 | 4 | 28° – 43° |
| February | 49° | 29° | 2.6" | 3.5" | 9 | 5 | 29° – 46° |
| March | 57° | 36° | 3.6" | 2.8" | 9 | 2 | 41° – 56° |
| April | 68° | 45° | 3.3" | 0.0" | 11 | 0 | 53° – 62° |
| May | 76° | 55° | 3.9" | 0.0" | 12 | 0 | 61° – 71° |
| June | 85° | 64° | 4.1" | 0.0" | 11 | 0 | 70° – 79° |
| July | 89° | 69° | 4.4" | 0.0" | 9 | 0 | 74° – 83° |
| August | 87° | 67° | 3.9" | 0.0" | 10 | 0 | 72° – 81° |
| September | 80° | 61° | 4.3" | 0.0" | 8 | 0 | 67° – 75° |
| October | 69° | 48° | 3.5" | 0.0" | 9 | 0 | 54° – 65° |
| November | 58° | 38° | 2.9" | 0.1" | 8 | 0 | 42° – 54° |
| December | 49° | 31° | 3.6" | 2.2" | 10 | 1 | 31° – 51° |
| Year | 68° | 47° | 42.9" | 13.4" | 116 | 12 |
How much a month can swing
A normal is an average. December swings the most: from 1991 to 2020 its average ranged from 31° to 51°. September is the most reliable, staying within 8°.
Where Potomac Heights’ numbers come from
Normals are 30-year averages, not a forecast. How TownRatings reads climate data →
- Temperatures and precipitation: NOAA’s gridded 1991–2020 normals for the 5 km cell at Potomac Heights’ center.
- Snow: Franconia 1.3 Sse, VA.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Quantico Mcas, VA, 11 miles from the town’s center, at about the same height; the nearest station that passes our checks for distance, height and agreement with the grid.
- Growing zone: USDA Plant Hardiness Zone Map, 2023. USDA Agricultural Research Service and PRISM Group, Oregon State University, prism.oregonstate.edu/phzm, accessed 8 Oct 2026.
- Then and now: NOAA’s gridded normals for 1901–2000 at the same cell.
- Storms and extremes: FEMA National Risk Index (expected annual losses to buildings).
Common questions about Potomac Heights’ climate
What is the weather like in Potomac Heights?
A typical July afternoon reaches 89°, a January night drops to 27°, and about 13 inches of snow falls in a normal winter. Milder January nights than 68% of U.S. towns; hotter July afternoons than 71% of U.S. towns.
How cold does it get in Potomac Heights in winter?
January nights average 27°. About 76 nights a year reach 32° or below. In the coldest January of the last 30 years the month averaged 28°.
How much snow does Potomac Heights get?
About 13 inches in a normal winter at Franconia 1.3 Sse, VA, most of it in January, with snow on the ground about 12 days a year.
How hot does it get in Potomac Heights?
July, with a typical high of 89° and a low of 69°. About 30 days a year reach 90° (Quantico Mcas, VA).
When is the first and last frost in Potomac Heights?
In half of years the last spring frost (32°) comes by March 28 and the first fall frost by November 8, about 226 frost-free days, at Quantico Mcas, VA.
What growing zone is Potomac Heights in?
Zone 7b on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about 9°.
What is the best time of year to visit Potomac Heights?
By one simple rule (highs of 62–84° and lows of 40° or more), April, May, September and October. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Potomac Heights getting warmer?
Yes: 1991–2020 averaged 1.8° warmer than 1901–2000 on NOAA’s grid. A bigger shift than 81% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Potomac Heights.
Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000; USDA/PRISM 2023 hardiness zones; FEMA National Risk Index. Today’s forecast: National Weather Service.