Guest, Sign inJoin
Climate in Hamilton Square · NOAA 1991–2020 normals

Hamilton Square has chilly winters and warm summers

A typical July afternoon reaches 87°, a January night drops to 24°, and about 27 inches of snow falls in a normal winter.

A year in Hamilton Square at a glance

Each month’s typical high and low, and what it brings.

Jan41°24° 8" snow
Feb44°25° 9" snow
Mar52°32° 4" snow
Apr64°41° Nice outLast frost ~25
May74°51° Nice out
Jun83°60° Nice out5 days 90°+
Jul87°66° 11 days 90°+Wettest
Aug85°64° 7 days 90°+
Sep78°57° Nice out
Oct now67°45° Nice outFirst frost ~16
Nov56°36°
Dec46°29° 5" snow

What stands out about Hamilton Square’s climate

Read from where Hamilton Square sits among New Jersey’s towns. The page puts what stands out first.

★ What stands out · Frost & heat

About 173 frost-free days a year

In half of years the last 32° night comes by April 25 and the first by October 16.

114
nights at or below 32° in a normal year
<1
nights below 0° in a normal year
26
days that reach 90° in a normal year

Freezing nights by month

Average nights at or below 32°

26
JFMAMJJASOND

90° days by month

Average days at 90° or more

11
JFMAMJJASOND
Living here

Living with Hamilton Square’s climate

What the numbers mean for a garden, a driveway, a furnace and a free afternoon.

The garden window

173 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 16.

Snow season

About 27" a winter over 7 days with an inch or more, most in February.

Furnace season

Months averaging under 55° run from November through April. Heating is 85% of the year’s heating-and-cooling load.

Summer heat

About 26 days a year reach 90°, and July afternoons average 87°.

Get outside

The nicest months are April, May, June, September and October. 1.8 miles of trails are waiting.

Parks & trails →
Storms and extremes

Normals are averages. Ice storms, nor’easters, floods and heat waves are on the natural hazards page.

Natural hazards →
A normal year

What a year in Hamilton Square feels like

Typical highs and lows by season and by month, from NOAA’s 30-year normals.

Winter
44° / 26°
7 days with 1"+ of snow
Spring
63° / 41°
Last frost around Apr 25
Summer
85° / 63°
26 days reach 90°
Fall
67° / 46°
First frost around Oct 16
Best months to be outsideAprMayJunSepOctHighs of 62–84° and lows of 40° or more
Rain & snow

27 inches of snow, 47 of rain and melt

July is the wettest month and February the driest. Rain or snow falls on about 130 days a year.

47"
Rain + melted snow a year
333rd driest of 941 New Jersey towns
More than 78% of U.S. towns
27"
Snow in a normal winter
281st snowiest of 898 New Jersey towns
More than 52% of U.S. towns
130 days
With rain or snow
109th wettest of 898 New Jersey towns
More than 75% of U.S. towns

Rain + melted snow by month

Inches of water

5.0"
JFMAMJJASOND

Snowfall by month

Inches of snow

8.7"
JFMAMJJASOND
Next door

Hamilton Square and its neighbors

West Windsor has the coldest January nights next door (24°) and Hamilton the hottest July afternoons (87°). Tap a town to see its climate.

Chesterfield: January low 24°, July high 87°Bordentown: January low 24°, July high 87°Groveville: January low 24°, July high 87°Crosswicks: January low 24°, July high 87°Lawrence: January low 23°, July high 87°Yardville: January low 24°, July high 87°North Hanover: January low 24°, July high 87°Trenton: January low 24°, July high 87°White Horse: January low 24°, July high 87°Bordentown: January low 24°, July high 87°Falls: January low 24°, July high 87°Upper Freehold: January low 24°, July high 87°Allentown: January low 24°, July high 87°East Windsor: January low 23°, July high 87°Millstone: January low 23°, July high 87°Plainsboro: January low 23°, July high 87°Princeton Junction: January low 24°, July high 87°Princeton: January low 23°, July high 86°Mercerville: January low 24°, July high 87°Hamilton: January low 24°, July high 87°Robbinsville: January low 24°, July high 87°Robbinsville Center: January low 24°, July high 87°West Windsor: January low 24°, July high 87°Hamilton Square: January low 24°, July high 87° Hamilton SquareMercervilleHamiltonRobbinsvilleRobbinsville CenterWest Windsor
ColderMilder23° to 24°
West Windsor23.7° −0.3°
Robbinsville23.8° −0.2°
Hamilton Square24.0°
Mercerville24.0° same
Hamilton24.2° +0.2°

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.

Then and now

Warmer than it used to be

The last 30 years in Hamilton Square averaged 2.2° warmer than the 1900s. The biggest change is in December (+3.8°).

+2.2°1991–2020 vs. 1901–2000

A bigger shift than in 98% of U.S. towns.

❄️ Winter+3.1°now 35°, was 32°
🌷 Spring+1.9°now 52°, was 50°
☀️ Summer+2.1°now 74°, was 72°
🍂 Fall+1.8°now 56°, was 54°

Change by month

JanFebMarAprMayJunJulAugSepOctNovDec
Compared with other towns

How Hamilton Square compares

Against every U.S. town on TownTapestry, each counted once, with its place in New Jersey.

Summer heat87° July high
Hotter than 66% of U.S. towns112th hottest of 941 New Jersey towns
Winter cold24° January low
Milder than 70% of U.S. towns453rd mildest of 941 New Jersey towns
Precipitation47" a year
Wetter than 78% of U.S. towns333rd driest of 941 New Jersey towns
Snow27" a winter
Snowier than 52% of U.S. towns281st snowiest of 898 New Jersey towns
Growing season173 frost-free days
Shorter than 57% of U.S. towns124th shortest of 941 New Jersey towns
Month by month

Hamilton Square weather by month

Average highs, lows, rain and snow for every month, from NOAA’s 1991–2020 normals.

MonthHighLowRain + meltSnowWet days30-yr range
January41°24°3.5" 8.2"1125° – 40°
February44°25°2.7" 8.7"1123° – 41°
March52°32°4.2" 4.0"1136° – 51°
April64°41°3.6" 0.5"1248° – 57°
May74°51°3.9" 01458° – 67°
June83°60°4.3" 01268° – 75°
July87°66°5.0" 01172° – 80°
August85°64°4.3" 01170° – 77°
September78°57°4.0" 0865° – 72°
October67°45°4.1" 0.1"1051° – 63°
November56°36°3.3" 0.5"841° – 50°
December46°29°4.2" 4.6"1130° – 49°
Year65°44°47.1"26.6"130
Heating & cooling

Heating and cooling a home in Hamilton Square

85% of the work is heating, so the furnace matters far more than the air conditioner.

85%heating
5,315 heating degree daysLess heating than 60% of U.S. towns
903 cooling degree daysMore cooling than 55% of U.S. towns

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.

Year to year

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°. September is the most reliable, staying within 7°.

Coldest to warmest month in 30 yearsNormal

Common questions about Hamilton Square’s climate

What is the coldest month in Hamilton Square?

January, with a typical high of 41° and a low of 24°.

What is the hottest month in Hamilton Square?

July, with a typical high of 87° and a low of 66°. About 26 days a year reach 90°.

How much snow does Hamilton Square get?

About 27 inches in a normal winter, most of it in February.

When is the first frost in Hamilton Square?

In half of years the first 32° night comes by October 16, and the last spring frost by April 25.

What is the rainiest month in Hamilton Square?

July, with 5.0 inches of rain and melted snow. The year totals 47 inches.

Neighbors talk weather

Gardens, snow, and the best days of the year in Hamilton Square.

Town Square →
Weigh in
Is Hamilton Square’s weather one of its best features?

Your answer becomes a post in Town Square.

Ask your neighbors

Temperatures and rainfall come from NOAA’s gridded climate normals for Hamilton Square itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Ewing Twp 0.8 Ese, NJ (8 mi, snow) and Hightstown 2 W, NJ (5 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.

Post to Hamilton Square

We’ll email a one-tap link to publish your post. No password, and nothing is public until you click it.
Already a member? Sign in