Port Morris has chilly winters and pleasant summers, with plenty of rain
A typical July afternoon reaches 82°, a January night drops to 18°, and about 30 inches of snow falls in a normal winter.
A year in Port Morris at a glance
Each month’s typical high and low, and what it brings.
What stands out about Port Morris’s climate
Read from where Port Morris sits among New Jersey’s towns. The page puts what stands out first.
What a year in Port Morris feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
30 inches of snow, 51 of rain and melt
July is the wettest month and February the driest. Rain or snow falls on about 120 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
About 175 frost-free days a year
In half of years the last 32° night comes by April 25 and the first by October 19.
Freezing nights by month
Average nights at or below 32°
90° days by month
Average days at 90° or more
Warmer than it used to be
The last 30 years in Port Morris averaged 1.9° warmer than the 1900s. The biggest change is in December (+3.6°).
A bigger shift than in 92% of U.S. towns.
Change by month
Living with Port Morris’s climate
What the numbers mean for a garden, a driveway, a furnace and a free afternoon.
175 frost-free days. The last frost comes by Apr 25 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 19.
About 30" a winter over 9 days with an inch or more, most in February. Snow covers the ground about 37 days a year.
Months averaging under 55° run from October through April. Heating is 90% of the year’s heating-and-cooling load.
About 11 days a year reach 90°, and July afternoons average 82°.
The nicest months are May, June, July, August, September and October.
Parks & trails →Normals are averages. Ice storms, nor’easters, floods and heat waves are on the natural hazards page.
Natural hazards →Port Morris and its neighbors
Byram has the coldest January nights next door (18°) and Byram the hottest July afternoons (83°). Tap a town to see its climate.
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.
How Port Morris compares
Against every U.S. town on TownTapestry, each counted once, with its place in New Jersey.
Port Morris 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 | 36° | 18° | 3.7" | 7.4" | 11 | 11 | 18° – 34° |
| February | 39° | 20° | 3.0" | 10.3" | 8 | 14 | 17° – 36° |
| March | 47° | 27° | 4.3" | 5.8" | 10 | 6 | 30° – 47° |
| April | 60° | 37° | 4.0" | 0.7" | 10 | 0 | 44° – 53° |
| May | 70° | 47° | 4.2" | 0 | 12 | 0 | 54° – 63° |
| June | 78° | 56° | 4.8" | 0 | 12 | 0 | 63° – 70° |
| July | 82° | 61° | 5.1" | 0 | 11 | 0 | 67° – 75° |
| August | 81° | 59° | 4.7" | 0 | 10 | 0 | 66° – 73° |
| September | 74° | 53° | 4.7" | 0 | 9 | 0 | 60° – 67° |
| October | 62° | 41° | 4.7" | 0.3" | 9 | 0 | 47° – 59° |
| November | 51° | 32° | 3.6" | 0.3" | 9 | 0 | 37° – 47° |
| December | 40° | 24° | 4.4" | 4.8" | 10 | 5 | 24° – 42° |
| Year | 60° | 40° | 51.3" | 29.6" | 120 | 37 |
Heating and cooling a home in Port Morris
90% of the work is heating, so the furnace matters far more than the air conditioner.
Degree days add up how far each day’s average falls below (heating) or rises above (cooling) 65° over a year. Source: NOAA station normals.
How much a month can swing
A normal is an average. February swings the most: from 1991 to 2020 its average ranged from 17° to 36°. June is the most reliable, staying within 6°.
Common questions about Port Morris’s climate
What is the coldest month in Port Morris?
January, with a typical high of 36° and a low of 18°.
What is the hottest month in Port Morris?
July, with a typical high of 82° and a low of 61°. About 11 days a year reach 90°.
How much snow does Port Morris get?
About 30 inches in a normal winter, most of it in February.
When is the first frost in Port Morris?
In half of years the first 32° night comes by October 19, and the last spring frost by April 25.
What is the rainiest month in Port Morris?
July, with 5.1 inches of rain and melted snow. The year totals 51 inches.
Neighbors talk weather
Gardens, snow, and the best days of the year in Port Morris.
Your answer becomes a post in Town Square.
Temperatures and rainfall come from NOAA’s gridded climate normals for Port Morris itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Pottersville 2 Nnw, NJ (12 mi, snow) and Andover Aeroflex Airport, NJ (8 mi, frost, heat and degree days). Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000. Today’s forecast: National Weather Service.