Colonia’s winters are milder and less snowy than most of the U.S.
A typical July afternoon reaches 87°, a January night drops to 24°, and about 21 inches of snow falls in a normal winter.
A year in Colonia at a glance
Each month’s typical high and low, and what it brings.
What stands out about Colonia’s climate
Compared with towns across the U.S., with Colonia’s place in New Jersey beside it.
What a year in Colonia feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 198 frost-free days a year
In half of years the last 32° night comes by April 11 and the first by October 28. Frost and day counts come from NOAA’s station at Plainfield, NJ, 5 miles from the town’s center, at about the same height.
The 2023 USDA map puts Colonia’s center in zone 7a: the coldest night of a typical winter, averaged over 1991–2020, reaches about 5°. 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 21 inches of snow a winter
Snow, measured at Plainfield, 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 117 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in Colonia
81% 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 Plainfield, NJ.
Living with Colonia’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
198 frost-free days in zone 7a. The last frost comes by Apr 11 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 28.
Months with highs of 62–84° and lows of 40° or more: April, May, June, September and October. 4.1 miles of trails are waiting.
Parks & trails →Of the yearly building losses FEMA expects in Colonia from natural hazards, river flooding is the largest share (74%); heat waves, cold waves, winter storms and ice storms together are 10%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Colonia and its neighbors
Every town next door is within a degree of Colonia in January and July, closer than the 5 km grid can tell apart. Tap a town to see its climate.
Climates most like Colonia’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 |
|---|---|---|---|---|
| Colonia, NJ | 24° | 87° | 48" | 21" |
| Owings Mills, MD | 24° | 87° | 48" | 19" |
| Cynthiana, KY | 24° | 87° | 48" | 16" |
| Amelia, OH | 23° | 86° | 46" | 23" |
| Lawrenceburg, IN | 23° | 86° | 45" | 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 Colonia averaged 2.2° warmer than the 1900s. The biggest change is in December (+3.6°).
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 Colonia compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Colonia’s place among New Jersey’s.
Colonia weather by month
Highs, lows and precipitation from NOAA’s grid at Colonia’s center; snow, wet days and snow on the ground from Plainfield, NJ. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | 30-yr range |
|---|---|---|---|---|---|---|
| January | 41° | 24° | 3.5" | 5.1" | 10 | 24° – 39° |
| February | 43° | 25° | 2.9" | 8.3" | 8 | 22° – 41° |
| March | 51° | 32° | 4.1" | 5.3" | 10 | 36° – 51° |
| April | 63° | 41° | 3.8" | 0.1" | 11 | 48° – 57° |
| May | 73° | 51° | 4.0" | 0.0" | 11 | 57° – 67° |
| June | 82° | 60° | 4.3" | 0.0" | 11 | 68° – 75° |
| July | 87° | 66° | 4.9" | 0.0" | 10 | 72° – 80° |
| August | 85° | 64° | 4.5" | 0.0" | 10 | 70° – 78° |
| September | 78° | 57° | 4.2" | 0.0" | 9 | 65° – 73° |
| October | 66° | 45° | 4.1" | 0.0" | 9 | 51° – 62° |
| November | 55° | 36° | 3.3" | 0.2" | 9 | 41° – 50° |
| December | 45° | 29° | 4.3" | 2.4" | 10 | 30° – 49° |
| Year | 64° | 44° | 47.9" | 21.4" | 117 |
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°. June is the most reliable, staying within 7°.
Where Colonia’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 Colonia’s center.
- Snow: Plainfield, NJ.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Plainfield, NJ, 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 Colonia’s climate
What is the weather like in Colonia?
A typical July afternoon reaches 87°, a January night drops to 24°, and about 21 inches of snow falls in a normal winter. Milder January nights than 59% of U.S. towns; hotter July afternoons than 61% of U.S. towns.
How cold does it get in Colonia in winter?
January nights average 24°. About 103 nights a year reach 32° or below. In the coldest January of the last 30 years the month averaged 24°.
How much snow does Colonia get?
About 21 inches in a normal winter at Plainfield, NJ, most of it in February.
How hot does it get in Colonia?
July, with a typical high of 87° and a low of 66°. About 29 days a year reach 90° and 1 reach 100° (Plainfield, NJ).
When is the first and last frost in Colonia?
In half of years the last spring frost (32°) comes by April 11 and the first fall frost by October 28, about 198 frost-free days, at Plainfield, NJ.
What growing zone is Colonia in?
Zone 7a on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about 5°.
What is the best time of year to visit Colonia?
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 Colonia 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 Colonia.
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.