Photo: IFCAR · Public domainIn Upper Marlboro, July heat, January chill and rainfall all sit near the middle of U.S. towns
On a normal July day the thermometer tops out near 88°. From frosty January to warm July, readings climb 62°. Summer afternoons here are warmer than in 68% of U.S. towns. Homes need heating from November to March, the months averaging under 50°.
A year in Upper Marlboro at a glance
Each month’s typical high and low, and what it brings.
What stands out about Upper Marlboro’s climate
Compared with towns across the U.S., with Upper Marlboro’s place in Maryland beside it.
What a year in Upper Marlboro feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 203 frost-free days a year
In half of years the last 32° night comes by April 9 and the first by October 29. Frost and day counts come from NOAA’s station at Upper Marlboro 3 Nnw, MD, 2.5 miles from the town’s center, at about the same height.
The 2023 USDA map puts Upper Marlboro’s center in zone 7b: the coldest night of a typical winter, averaged over 1991–2020, reaches about 8°. 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 16 inches of snow a winter
Snow, measured at Upper Marlboro 3 Nnw, MD, is heaviest from January through February, about 6 inches a month. Precipitation (rain plus melted snow) adds up to 45 inches a year; July is the wettest month and February the driest. Rain or snow falls on about 111 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in Upper Marlboro
78% 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 Upper Marlboro 3 Nnw, MD.
Living with Upper Marlboro’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
203 frost-free days in zone 7b. The last frost comes by Apr 9 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 29.
Months with highs of 62–84° and lows of 40° or more: April, May, June, September and October.
Parks & trails →Of the yearly building losses FEMA expects in Upper Marlboro from natural hazards, river flooding is the largest share (58%); heat waves, cold waves, winter storms and ice storms together are 11%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Upper Marlboro and its neighbors
Every town next door is within a degree of Upper Marlboro in January and July, closer than the 5 km grid can tell apart. Tap a town to see its climate.
Climates most like Upper Marlboro’s, 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 |
|---|---|---|---|---|
| Upper Marlboro, MD | 26° | 88° | 45" | 16" |
| Vinton, VA | 27° | 88° | 45" | 15" |
| Republic, MO | 23° | 88° | 45" | 14" |
| Henderson, KY | 25° | 88° | 48" | 12" |
| Du Quoin, IL | 24° | 88° | 46" | 12" |
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 Upper Marlboro averaged 1.6° warmer than the 1900s. The biggest change is in December (+2.7°).
A bigger shift than in 64% 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 Upper Marlboro compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Upper Marlboro’s place among Maryland’s.
Upper Marlboro weather by month
Highs, lows and precipitation from NOAA’s grid at Upper Marlboro’s center; snow, wet days and snow on the ground from Upper Marlboro 3 Nnw, MD. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 44° | 26° | 3.0" | 5.7" | 10 | 4 | 27° – 42° |
| February | 48° | 28° | 2.7" | 6.3" | 9 | 6 | 27° – 45° |
| March | 56° | 34° | 4.0" | 1.7" | 10 | 2 | 39° – 54° |
| April | 67° | 44° | 3.3" | 0.0" | 10 | 0 | 52° – 61° |
| May | 76° | 54° | 4.0" | 0.0" | 10 | 0 | 60° – 71° |
| June | 84° | 63° | 4.3" | 0.0" | 11 | 0 | 69° – 78° |
| July | 88° | 68° | 4.5" | 0.0" | 9 | 0 | 73° – 81° |
| August | 86° | 66° | 4.2" | 0.0" | 9 | 0 | 71° – 80° |
| September | 80° | 59° | 4.5" | 0.0" | 8 | 0 | 66° – 74° |
| October | 69° | 47° | 3.8" | 0.0" | 8 | 0 | 54° – 64° |
| November | 58° | 37° | 3.1" | 0.0" | 7 | 0 | 41° – 52° |
| December | 48° | 30° | 3.7" | 2.2" | 10 | 2 | 30° – 50° |
| Year | 67° | 46° | 45.1" | 15.9" | 111 | 14 |
How much a month can swing
A normal is an average. December swings the most: from 1991 to 2020 its average ranged from 30° to 50°. September is the most reliable, staying within 7°.
Where Upper Marlboro’s 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 Upper Marlboro’s center.
- Snow: Upper Marlboro 3 Nnw, MD.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Upper Marlboro 3 Nnw, MD, 2.5 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 Upper Marlboro’s climate
What is the weather like in Upper Marlboro?
A typical July afternoon reaches 88°, a January night drops to 26°, and about 16 inches of snow falls in a normal winter. Milder January nights than 66% of U.S. towns; hotter July afternoons than 68% of U.S. towns.
How cold does it get in Upper Marlboro in winter?
January nights average 26°. About 103 nights a year reach 32° or below. In the coldest January of the last 30 years the month averaged 27°.
How much snow does Upper Marlboro get?
About 16 inches in a normal winter at Upper Marlboro 3 Nnw, MD, heaviest from January through February, about 6 inches a month, with snow on the ground about 14 days a year.
How hot does it get in Upper Marlboro?
July, with a typical high of 88° and a low of 68°. About 32 days a year reach 90° (Upper Marlboro 3 Nnw, MD).
When is the first and last frost in Upper Marlboro?
In half of years the last spring frost (32°) comes by April 9 and the first fall frost by October 29, about 203 frost-free days, at Upper Marlboro 3 Nnw, MD.
What growing zone is Upper Marlboro in?
Zone 7b on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about 8°.
What is the best time of year to visit Upper Marlboro?
By one simple rule (highs of 62–84° and lows of 40° or more), April, May, June, September and October. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Upper Marlboro getting warmer?
Yes: 1991–2020 averaged 1.6° warmer than 1901–2000 on NOAA’s grid. A bigger shift than 64% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Upper Marlboro.
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.