Ensley-Mount-Buckalew House · Photo: Rickyrab at English Wikipedia · CC BY-SA 3.0Wet weather: 48 inches of rain and melted snow a year in Jamesburg, more than in 73% of U.S. towns
Midwinter brings lows of about 23°. July is the wettest month, February the driest. Summer afternoons here are warmer than in 62% of U.S. towns. From April to June and September to October, highs of 64–82° make it easy to spend the day outdoors.
A year in Jamesburg at a glance
Each month’s typical high and low, and what it brings.
What stands out about Jamesburg’s climate
Compared with towns across the U.S., with Jamesburg’s place in New Jersey beside it.
What a year in Jamesburg feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 193 frost-free days a year
In half of years the last 32° night comes by April 15 and the first by October 26. Frost and day counts come from NOAA’s station at New Brunswick 3 Se, NJ, 9 miles from the town’s center, at about the same height.
The 2023 USDA map puts Jamesburg’s center in zone 7a: the coldest night of a typical winter, averaged over 1991–2020, reaches about 4°. 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 29 inches of snow a winter
Snow, measured at New Brunswick 3 Se, NJ, falls mostly in February. Precipitation (rain plus melted snow) adds up to 48 inches a year; July is the wettest month and February the driest. Rain or snow falls on about 125 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in Jamesburg
83% of the work is heating. Months averaging under 55° run from November through April.
Degree days add up how far each day’s average falls below (heating) or rises above (cooling) 65° over a year. NOAA normals at New Brunswick 3 Se, NJ.
Living with Jamesburg’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
193 frost-free days in zone 7a. The last frost comes by Apr 15 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 26.
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 Jamesburg from natural hazards, river flooding is the largest share (64%); heat waves, cold waves, winter storms and ice storms together are 14%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Jamesburg and similar climates
TownRatings has no climate map of the towns around Jamesburg yet.
Climates most like Jamesburg’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 |
|---|---|---|---|---|
| Jamesburg, NJ | 23° | 87° | 48" | 29" |
| Columbia, MD | 25° | 87° | 46" | 29" |
| Charleston, WV | 25° | 87° | 46" | 32" |
| Gettysburg, PA | 22° | 87° | 45" | 27" |
| Alexandria, KY | 24° | 86° | 45" | 23" |
Temperatures and precipitation come from NOAA’s 5 km grid; snow and day counts from the stations named on this page.
Warmer than it used to be
The last 30 years in Jamesburg averaged 2.3° warmer than the 1900s. The biggest change is in December (+3.9°).
A bigger shift than in 98% 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 Jamesburg compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Jamesburg’s place among New Jersey’s.
Jamesburg weather by month
Highs, lows and precipitation from NOAA’s grid at Jamesburg’s center; snow, wet days and snow on the ground from New Brunswick 3 Se, NJ. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 41° | 23° | 3.6" | 8.3" | 11 | 9 | 24° – 40° |
| February | 44° | 25° | 2.8" | 9.3" | 10 | 10 | 23° – 41° |
| March | 52° | 31° | 4.2" | 5.2" | 11 | 5 | 36° – 50° |
| April | 64° | 40° | 3.7" | 0.6" | 12 | 0 | 48° – 56° |
| May | 73° | 50° | 4.0" | 0.0" | 13 | 0 | 57° – 67° |
| June | 82° | 60° | 4.4" | 0.0" | 11 | 0 | 67° – 75° |
| July | 87° | 65° | 4.9" | 0.0" | 11 | 0 | 72° – 80° |
| August | 85° | 63° | 4.3" | 0.0" | 10 | 0 | 70° – 77° |
| September | 78° | 57° | 4.0" | 0.0" | 9 | 0 | 65° – 72° |
| October | 67° | 45° | 4.2" | 0.2" | 10 | 0 | 51° – 63° |
| November | 56° | 35° | 3.3" | 0.5" | 9 | 0 | 41° – 50° |
| December | 46° | 28° | 4.3" | 4.9" | 10 | 4 | 30° – 49° |
| Year | 65° | 44° | 47.5" | 29.0" | 125 | 27 |
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 49°. September is the most reliable, staying within 7°.
Where Jamesburg’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 Jamesburg’s center.
- Snow: New Brunswick 3 Se, NJ.
- Frost, freezing nights, 90° and 100° days, heating and cooling: New Brunswick 3 Se, NJ, 9 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 Jamesburg’s climate
What is the weather like in Jamesburg?
A typical July afternoon reaches 87°, a January night drops to 23°, and about 29 inches of snow falls in a normal winter. Milder January nights than 57% of U.S. towns; hotter July afternoons than 62% of U.S. towns.
How cold does it get in Jamesburg in winter?
January nights average 23°. About 111 nights a year reach 32° or below. In the coldest January of the last 30 years the month averaged 24°.
How much snow does Jamesburg get?
About 29 inches in a normal winter at New Brunswick 3 Se, NJ, most of it in February, with snow on the ground about 27 days a year.
How hot does it get in Jamesburg?
July, with a typical high of 87° and a low of 65°. About 24 days a year reach 90° (New Brunswick 3 Se, NJ).
When is the first and last frost in Jamesburg?
In half of years the last spring frost (32°) comes by April 15 and the first fall frost by October 26, about 193 frost-free days, at New Brunswick 3 Se, NJ.
What growing zone is Jamesburg in?
Zone 7a on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about 4°.
What is the best time of year to visit Jamesburg?
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 Jamesburg getting warmer?
Yes: 1991–2020 averaged 2.3° warmer than 1901–2000 on NOAA’s grid. A bigger shift than 98% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Jamesburg.
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.