Photo: Dough4872 · Public domainSummers, winters and rain in South Dennis all run close to those of most U.S. towns
In January the night’s low is typically 25°. A year here swings 60° from midwinter lows to midsummer highs. By precipitation alone, it ranks wetter than 66% of U.S. towns. The outdoor season runs from April to June and August to October, with highs of 63–84°.
A year in South Dennis at a glance
Each month’s typical high and low, and what it brings.
What stands out about South Dennis’ climate
Compared with towns across the U.S., with South Dennis’ place in New Jersey beside it.
What a year in South Dennis feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 181 frost-free days a year
In half of years the last 32° night comes by April 24 and the first by October 22. Frost and day counts come from NOAA’s station at Belleplain Stn Forest, NJ, 6 miles from the town’s center, at about the same height.
The 2023 USDA map puts South Dennis’ 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 22 inches of snow a winter
Snow, measured at Estell Manor, NJ, falls mostly in February. Precipitation (rain plus melted snow) adds up to 46 inches a year; August 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 South Dennis
80% 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 Belleplain Stn Forest, NJ.
Living with South Dennis’ climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
181 frost-free days in zone 7b. The last frost comes by Apr 24 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 22.
Months with highs of 62–84° and lows of 40° or more: April, May, June, August, September and October. 0.0 miles of trails are waiting.
Parks & trails →Of the yearly building losses FEMA expects in South Dennis from natural hazards, river flooding is the largest share (38%); heat waves, cold waves, winter storms and ice storms together are 13%. Normals are averages; the hazards page covers the extremes.
Natural hazards →South Dennis and its neighbors
Every town next door is within a degree of South Dennis in January and July, closer than the 5 km grid can tell apart. Tap a town to see its climate.
Climates most like South Dennis’, 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 |
|---|---|---|---|---|
| South Dennis, NJ | 25° | 85° | 46" | 22" |
| Independence, KY | 23° | 86° | 46" | 23" |
| Amelia, OH | 23° | 86° | 46" | 23" |
| Lawrenceburg, IN | 23° | 86° | 45" | 23" |
| Clarksburg, WV | 23° | 85° | 47" | 24" |
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 South Dennis averaged 2.2° warmer than the 1900s. The biggest change is in December (+3.4°).
A bigger shift than in 97% 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 South Dennis compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with South Dennis’ place among New Jersey’s.
South Dennis weather by month
Highs, lows and precipitation from NOAA’s grid at South Dennis’ center; snow, wet days and snow on the ground from Estell Manor, NJ. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 43° | 25° | 3.4" | 6.1" | 11 | 5 | 28° – 41° |
| February | 45° | 27° | 3.1" | 8.2" | 11 | 7 | 25° – 43° |
| March | 52° | 33° | 4.4" | 3.4" | 12 | 2 | 38° – 50° |
| April | 63° | 42° | 3.5" | 0.7" | 12 | 0 | 49° – 57° |
| May | 72° | 51° | 3.3" | 0.0" | 11 | 0 | 56° – 67° |
| June | 80° | 61° | 3.7" | 0.0" | 11 | 0 | 67° – 75° |
| July | 85° | 67° | 4.4" | 0.0" | 10 | 0 | 72° – 79° |
| August | 84° | 65° | 4.7" | 0.0" | 9 | 0 | 70° – 78° |
| September | 78° | 59° | 3.9" | 0.0" | 9 | 0 | 65° – 72° |
| October | 67° | 47° | 4.2" | 0.0" | 10 | 0 | 53° – 63° |
| November | 57° | 37° | 3.4" | 0.0" | 9 | 0 | 41° – 51° |
| December | 48° | 30° | 4.3" | 3.6" | 11 | 3 | 31° – 50° |
| Year | 65° | 45° | 46.2" | 22.0" | 125 | 17 |
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°. August is the most reliable, staying within 7°.
Where South Dennis’ 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 South Dennis’ center.
- Snow: Estell Manor, NJ.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Belleplain Stn Forest, NJ, 6 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 South Dennis’ climate
What is the weather like in South Dennis?
A typical July afternoon reaches 85°, a January night drops to 25°, and about 22 inches of snow falls in a normal winter. Milder January nights than 64% of U.S. towns; hotter July afternoons than 52% of U.S. towns.
How cold does it get in South Dennis in winter?
January nights average 25°. About 118 nights a year reach 32° or below. In the coldest January of the last 30 years the month averaged 28°.
How much snow does South Dennis get?
About 22 inches in a normal winter at Estell Manor, NJ, most of it in February, with snow on the ground about 17 days a year.
How hot does it get in South Dennis?
July, with a typical high of 85° and a low of 67°. About 28 days a year reach 90° (Belleplain Stn Forest, NJ).
When is the first and last frost in South Dennis?
In half of years the last spring frost (32°) comes by April 24 and the first fall frost by October 22, about 181 frost-free days, at Belleplain Stn Forest, NJ.
What growing zone is South Dennis 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 South Dennis?
By one simple rule (highs of 62–84° and lows of 40° or more), April, May, June, August, September and October. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is South Dennis getting warmer?
Yes: 1991–2020 averaged 2.2° warmer than 1901–2000 on NOAA’s grid. A bigger shift than 97% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in South Dennis.
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.