Penns Grove, NJ climate
Penns Grove has chilly winters and warm summers. A typical July afternoon reaches 87°, a January night drops to 26°, and about 20 inches of snow falls in a normal winter.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in Penns Grove feels like
Winter
Spring
Summer
Fall
Penns Grove weather by month
Average highs, lows, rain and snow for every month, from NOAA’s 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 42° | 26° | 3.2" | 6.1" | 11 | 5 | 26° – 41° |
| February | 44° | 27° | 2.8" | 7.8" | 10 | 7 | 26° – 43° |
| March | 53° | 34° | 4.2" | 3.1" | 11 | 3 | 38° – 52° |
| April | 65° | 43° | 3.6" | 0.1" | 11 | 0 | 50° – 59° |
| May | 74° | 53° | 3.5" | 0 | 12 | 0 | 59° – 69° |
| June | 83° | 63° | 4.3" | 0 | 11 | 0 | 69° – 77° |
| July | 87° | 68° | 4.5" | 0 | 10 | 0 | 74° – 81° |
| August | 85° | 66° | 4.3" | 0 | 9 | 0 | 71° – 79° |
| September | 79° | 59° | 4.4" | 0 | 9 | 0 | 66° – 73° |
| October | 67° | 48° | 3.8" | 0 | 9 | 0 | 53° – 64° |
| November | 56° | 38° | 3.2" | 0.2" | 9 | 0 | 41° – 52° |
| December | 46° | 30° | 3.9" | 2.9" | 11 | 2 | 30° – 51° |
| Year | 65° | 46° | 45.6" | 20.2" | 122 | 17 |
“Wet days” have at least 0.01" of rain or melted snow. “Snow on ground” counts days with 1" or more. The 30-year range is the coldest and warmest that month’s average temperature got between 1991 and 2020.
Rain and snow in Penns Grove
Penns Grove gets 46 inches of rain and melted snow a year. July is the wettest month and February the driest. Rain or snow falls on about 122 days a year. Snow covers the ground about 17 days of the year.
About 209 frost-free days a year
In half of years the last 32° night comes by April 7 and the first one by November 1. That leaves about 209 frost-free days for gardens, longer than 78% of U.S. towns.
Heating and cooling a home in Penns Grove
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Penns Grove, 79% of that work is heating and 21% is cooling.
Degree days measure how far each day’s average temperature falls below or rises above 65°, added up over a year. Source: NOAA station normals.
Penns Grove and its neighbors
Penns Grove borders 2 towns with climate data. January nights across them vary by 0.5°. Wilmington has both the coldest January nights (25°) and the hottest July afternoons (87°). Penns Grove’s January low is 26° and its July high 87°.
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value.
How Penns Grove compares
Compared with every U.S. town and city on TownTapestry, each counted once.
Warmer than it used to be
The last 30 years in Penns Grove averaged 1.9° warmer than the 1900s. The biggest change is in December (+3.4°). The shift is larger than in 89% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Penns Grove’s spot on NOAA’s grid
How much a month can swing
A normal is an average, and real years wander around it. December swings the most: between 1991 and 2020 its average temperature ranged from 30° to 51°. September is the most reliable, staying within 7°.
Common questions about Penns Grove’s climate
What is the coldest month in Penns Grove?
January, with a typical high of 42° and a low of 26°.
What is the hottest month in Penns Grove?
July, with a typical high of 87° and a low of 68°. About 22 days a year reach 90°.
How much snow does Penns Grove get?
About 20 inches in a normal winter, most of it in February.
When is the first frost in Penns Grove?
In half of years the first 32° night comes by November 1, and the last spring frost by April 7.
What is the rainiest month in Penns Grove?
July, with 4.5 inches of rain and melted snow. The year totals 46 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Penns Grove itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Wilmington New Castle Co Airport, DE (8 mi) away. Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000.