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Hamilton Square, NJPhoto: Mr. Matté (if there is an issue with this image, contact me using this image's Commons talk page, my Commons user talk page, or my English Wikipedia user talk page; I'll know about it a lot faster) · CC BY 3.0
Climate in Hamilton Square · NOAA 1991–2020 normals

In Hamilton Square, July heat, January chill and rainfall all sit near the middle of U.S. towns

On a normal January night the air cools to about 24°. It is a wet place: more rain and snow fall here than on 71% of U.S. towns. Compared with 1901–2000, the average now sits 2.2° higher. For walks and days out, the stretch from April to June and September to October brings highs of 64–83°.

Milder January nights than 60% of U.S. towns#214Mildest winters  of 467 in NJ
More snow than 57% of U.S. towns#158Snowiest  of 452 in NJ
All NJ rankings →

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° Last frost ~Apr 25
May74°51° 1 day 90°+
Jun83°60° 5 days 90°+
Jul87°66° 11 days 90°+Wettest
Aug85°64° 7 days 90°+
Sep78°57° 2 days 90°+
Oct67°45° First frost ~Oct 16
Nov now56°36°
Dec46°29° 5" snow

What stands out about Hamilton Square’s climate

Compared with towns across the U.S., with Hamilton Square’s place in New Jersey beside it.

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
Frost, heat & the growing season

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. Frost and day counts come from NOAA’s station at Hightstown 2 W, NJ, 5 miles from the town’s center, at about the same height.

114
nights at or below 32° in a normal year
184th most of 467 in New Jersey
More freezing nights than 50% of U.S. towns
<1
nights at or below 0°
271st fewest of 467 in New Jersey
Fewer nights at or below 0° than 58% of U.S. towns
26
days that reach 90°
138th most of 467 in New Jersey
More 90° days than 58% of U.S. towns
<1
days that reach 100°
282nd most of 467 in New Jersey
More 100° days than 52% of U.S. towns
7aUSDA zone
Plant hardiness zone 7a

The 2023 USDA map puts Hamilton Square’s center in zone 7a: the coldest night of a typical winter, averaged over 1991–2020, reaches about 4°. Plant labels use the zone; frost dates tell you when to plant.

Freezing nights by month

Average nights at or below 32°

26
JFMAMJJASOND

90° days by month

Average days at 90° or more

11
JFMAMJJASOND
Rain & snow

About 27 inches of snow a winter

Snow, measured at Ewing Twp 0.8 Ese, NJ, is heaviest from January through February, about 8 inches a month. Precipitation (rain plus melted snow) adds up to 47 inches a year; 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
311th wettest of 467 in New Jersey
Wetter than 71% of U.S. towns
27"
Snow in a normal winter
158th snowiest of 452 in New Jersey
More snow than 57% of U.S. towns

Rain + melted snow by month

Inches of water

5.0"
JFMAMJJASOND

Snowfall by month

Inches of snow

9"
JFMAMJJASOND
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. Months averaging under 55° run from November through April.

5,315 heating degree daysLess heating than 50% of U.S. towns
903 cooling degree daysLess cooling than 51% 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. NOAA normals at Hightstown 2 W, NJ.

Living here

Living with Hamilton Square’s climate

What the numbers mean for a garden, a free afternoon and a bad-weather day.

The garden window

173 frost-free days in zone 7a. 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.

Get outside

Months with highs of 62–84° and lows of 40° or more: April, May, June, September and October. 1.8 miles of trails are waiting.

Parks & trails →
Storms and extremes

Of the yearly building losses FEMA expects in Hamilton Square from natural hazards, river flooding is the largest share (55%); heat waves, cold waves, winter storms and ice storms together are 12%. Normals are averages; the hazards page covers the extremes.

Natural hazards →
Next door

Hamilton Square and its neighbors

Every town next door is within a degree of Hamilton Square in January and July, closer than the 5 km grid can tell apart. Tap a town to see its climate.

Chesterfield Township: January low 24°, July high 87°Bordentown Township: January low 24°, July high 87°Groveville: January low 24°, July high 87°Crosswicks: January low 24°, July high 87°Lawrence Township: January low 23°, July high 87°Yardville: January low 24°, July high 87°North Hanover Township: 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 Township: January low 24°, July high 87°Upper Freehold Township: January low 24°, July high 87°Allentown: January low 24°, July high 87°East Windsor Township: January low 23°, July high 87°Millstone Township: January low 23°, July high 87°Plainsboro Township: 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 Township: January low 24°, July high 87°Robbinsville Township: January low 24°, July high 87°Robbinsville Center: January low 24°, July high 87°West Windsor Township: January low 24°, July high 87°Hamilton Square: January low 24°, July high 87°Hamilton SquareMercervilleHamilton TownshipRobbinsville TownshipRobbinsville CenterWest Windsor Township
ColderMilder23° to 24°
West Windsor Township23.7° about the same
Robbinsville Township23.8° about the same
Hamilton Square24.0°
Mercerville24.0° about the same
Robbinsville Center24.0° about the same
Hamilton Township24.2° about the same

Climates most like Hamilton Square’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.

TownJan. lowJuly highPrecip.Snow
Hamilton Square, NJ24°87°47"27"
Charleston, WV25°87°46"32"
Thurmont, MD23°87°44"28"
Fort Thomas, KY24°87°45"23"
Forestville, OH23°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.

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 97% 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

The two periods overlap (1991–2000 is in both), which makes the gap a little smaller than it would be between separate periods.

Compared with other towns

How Hamilton Square compares

Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Hamilton Square’s place among New Jersey’s.

Summer heat87° July high
Hotter July afternoons than 63% of U.S. towns59th hottest of 467 in New Jersey
Winter cold24° January low
Milder January nights than 60% of U.S. towns214th mildest of 467 in New Jersey
Precipitation47" a year
Wetter than 71% of U.S. towns311th wettest of 467 in New Jersey
Snow27" a winter
More snow than 57% of U.S. towns158th snowiest of 452 in New Jersey
Hot days26 days at 90°+
More 90° days than 58% of U.S. towns138th most of 467 in New Jersey
Freezing nights114 a year
More freezing nights than 50% of U.S. towns184th most of 467 in New Jersey
Growing season173 frost-free days
A shorter frost-free season than 68% of U.S. towns36th shortest of 467 in New Jersey
Month by month

Hamilton Square weather by month

Highs, lows and precipitation from NOAA’s grid at Hamilton Square’s center; snow, wet days and snow on the ground from Ewing Twp 0.8 Ese, NJ. 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"0.0"1458° – 67°
June83°60°4.3"0.0"1268° – 75°
July87°66°5.0"0.0"1172° – 80°
August85°64°4.3"0.0"1170° – 77°
September78°57°4.0"0.0"865° – 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
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
Sources

Where Hamilton Square’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 Hamilton Square’s center.
  • Snow: Ewing Twp 0.8 Ese, NJ.
  • Frost, freezing nights, 90° and 100° days, heating and cooling: Hightstown 2 W, 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 Hamilton Square’s climate

What is the weather like in Hamilton Square?

A typical July afternoon reaches 87°, a January night drops to 24°, and about 27 inches of snow falls in a normal winter. Milder January nights than 60% of U.S. towns; hotter July afternoons than 63% of U.S. towns.

How cold does it get in Hamilton Square in winter?

January nights average 24°. About 114 nights a year reach 32° or below. In the coldest January of the last 30 years the month averaged 25°.

How much snow does Hamilton Square get?

About 27 inches in a normal winter at Ewing Twp 0.8 Ese, NJ, heaviest from January through February, about 8 inches a month.

How hot does it get in Hamilton Square?

July, with a typical high of 87° and a low of 66°. About 26 days a year reach 90° (Hightstown 2 W, NJ).

When is the first and last frost in Hamilton Square?

In half of years the last spring frost (32°) comes by April 25 and the first fall frost by October 16, about 173 frost-free days, at Hightstown 2 W, NJ.

What growing zone is Hamilton Square in?

Zone 7a on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about 4°.

What is the best time of year to visit Hamilton Square?

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 Hamilton Square 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 Hamilton Square.

Town Square →
Ask your neighbors

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.