Photo: Mr. Matté (if there is an issue with this image, contact me using this image's Commons talk page, my Commons user talk page, or my English Wikipedia user talk page; I'll know about it a lot faster) · CC BY-SA 4.0Sewaren gets more rain and snow than 73% of U.S. towns: 48 inches of precipitation a year
Nights in January average 26°. By January nights alone, it runs milder than 64% of U.S. towns. Since 1901–2000, the year has warmed by 2.2°, most of all in December. Long walks are most pleasant from April to June and September to October, when afternoons reach 62–81°.
A year in Sewaren at a glance
Each month’s typical high and low, and what it brings.
What stands out about Sewaren’s climate
Compared with towns across the U.S., with Sewaren’s place in New Jersey beside it.
What a year in Sewaren 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, 10 miles from the town’s center, at about the same height.
The 2023 USDA map puts Sewaren’s center in zone 7b: the coldest night of a typical winter, averaged over 1991–2020, reaches about 6°. 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 32 inches of snow a winter
Snow, measured at Newark International Airport, is heaviest from January through February, about 10 inches a month. 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 123 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in Sewaren
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 Sewaren’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
193 frost-free days in zone 7b. 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. 0.4 miles of trails are waiting.
Parks & trails →Of the yearly building losses FEMA expects in Sewaren from natural hazards, river flooding is the largest share (43%); heat waves, cold waves, winter storms and ice storms together are 10%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Sewaren and its neighbors
Woodbridge Township has the coldest January nights next door (24°, 1° colder). Differences under a degree are within what the 5 km grid can tell apart. Tap a town to see its climate.
Climates most like Sewaren’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 |
|---|---|---|---|---|
| Sewaren, NJ | 26° | 86° | 48" | 32" |
| Charleston, WV | 25° | 87° | 46" | 32" |
| Redland, MD | 25° | 86° | 45" | 33" |
| Independence, KY | 23° | 86° | 46" | 23" |
| Amelia, OH | 23° | 86° | 46" | 23" |
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 Sewaren averaged 2.2° warmer than the 1900s. The biggest change is in December (+3.7°).
A bigger shift than in 96% 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 Sewaren compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Sewaren’s place among New Jersey’s.
Sewaren weather by month
Highs, lows and precipitation from NOAA’s grid at Sewaren’s center; snow, wet days and snow on the ground from Newark International Airport. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 41° | 26° | 3.5" | 9.1" | 11 | 8 | 25° – 40° |
| February | 43° | 27° | 2.9" | 10.1" | 10 | 8 | 23° – 41° |
| March | 51° | 33° | 4.2" | 5.6" | 11 | 3 | 37° – 51° |
| April | 62° | 43° | 3.7" | 0.5" | 12 | 0 | 49° – 57° |
| May | 72° | 53° | 4.0" | 0.0" | 11 | 0 | 58° – 67° |
| June | 81° | 62° | 4.3" | 0.0" | 11 | 0 | 68° – 75° |
| July | 86° | 68° | 4.9" | 0.0" | 10 | 0 | 72° – 81° |
| August | 84° | 66° | 4.5" | 0.0" | 10 | 0 | 71° – 79° |
| September | 78° | 60° | 4.0" | 0.0" | 9 | 0 | 66° – 74° |
| October | 66° | 48° | 4.1" | 0.2" | 9 | 0 | 53° – 64° |
| November | 55° | 39° | 3.3" | 0.6" | 9 | 0 | 42° – 52° |
| December | 45° | 31° | 4.3" | 5.4" | 11 | 3 | 31° – 50° |
| Year | 64° | 46° | 47.6" | 31.5" | 123 | 22 |
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 50°. June is the most reliable, staying within 7°.
Where Sewaren’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 Sewaren’s center.
- Snow: Newark International Airport.
- Frost, freezing nights, 90° and 100° days, heating and cooling: New Brunswick 3 Se, NJ, 10 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 Sewaren’s climate
What is the weather like in Sewaren?
A typical July afternoon reaches 86°, a January night drops to 26°, and about 32 inches of snow falls in a normal winter. Milder January nights than 64% of U.S. towns; hotter July afternoons than 56% of U.S. towns.
How cold does it get in Sewaren in winter?
January nights average 26°. About 111 nights a year reach 32° or below. In the coldest January of the last 30 years the month averaged 25°.
How much snow does Sewaren get?
About 32 inches in a normal winter at Newark International Airport, heaviest from January through February, about 10 inches a month, with snow on the ground about 22 days a year.
How hot does it get in Sewaren?
July, with a typical high of 86° and a low of 68°. About 24 days a year reach 90° (New Brunswick 3 Se, NJ).
When is the first and last frost in Sewaren?
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 Sewaren in?
Zone 7b on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about 6°.
What is the best time of year to visit Sewaren?
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 Sewaren getting warmer?
Yes: 1991–2020 averaged 2.2° warmer than 1901–2000 on NOAA’s grid. A bigger shift than 96% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Sewaren.
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.