Williamstown in Spring
In spring (March, April and May), Williamstown sees average daytime highs around 63°F and overnight lows near 46°F, with 10.9 in of precipitation over about 32 wet days across the season. It is the 3rd-warmest season and the 2nd-wettest season.
Over the season highs climb from about 49°F in early March to 77°F by late May. The sky is clear or mostly clear about 28% of the time across spring, and the air most often feels dry.
Spring is Williamstown's 3rd-best season to visit on our travel score. For the whole year in context, see Williamstown's year-round climate.
- Avg daytime high
- 63°F
- 3rd-warmest season
- Avg overnight low
- 46°F
- Precipitation
- 10.9 in
- 32 wet days
- Avg wind
- 8 mph
- Travel score
- 4.9
- 3rd-best season
- Months
- Mar · Apr · May
Temperature in Williamstown in Spring
Over the season highs climb from about 49°F in early March to 77°F by late May.
A typical spring day in Williamstown reaches about 63°F and drops to 46°F overnight. The warmest of the three months is May, the coolest March.
How spring really feels in Williamstown
Once humidity and wind are folded in, spring brings about 0 days that feel above 90°F and 23 that feel at or below 32°F.
The story in spring is cold — wind chill drags the overnight "feels like" below the raw low.
Williamstown weather by month
How the three spring months (March, April and May) compare with the rest of the year — the season's months are highlighted.
| Month | High / Low (°F) | Rainfall (inches) | Wet days | Snow days | Daylight (hours) | Travel score |
|---|---|---|---|---|---|---|
| Jan | 42° / 28° | 3.1 | 9.2 | 3.3 | 9.5 | 0.2 |
| Feb | 44° / 29° | 3.0 | 9 | 3.2 | 10.4 | 0.8 |
| Mar | 52° / 36° | 4.0 | 10.6 | 2 | 11.7 | 2.8 |
| Apr | 64° / 46° | 3.4 | 10.6 | 0.3 | 13 | 5.5 |
| May | 73° / 55° | 3.4 | 10.8 | 0 | 14.2 | 6.5 |
| Jun | 82° / 65° | 3.8 | 10.7 | 0 | 14.8 | 6.0 |
| Jul | 86° / 70° | 3.8 | 11.2 | 0 | 14.5 | 4.9 |
| Aug | 84° / 68° | 4.2 | 10.4 | 0 | 13.6 | 5.5 |
| Sep | 78° / 61° | 3.9 | 9.3 | 0 | 12.3 | 6.9 |
| Oct | 67° / 50° | 3.6 | 8 | 0 | 10.9 | 6.4 |
| Nov | 56° / 40° | 2.9 | 7.9 | 0.2 | 9.8 | 3.9 |
| Dec | 46° / 33° | 3.9 | 9.4 | 1.8 | 9.2 | 1.4 |
Cloud cover in Spring
The sky is clear or mostly clear about 28% of the time across spring.
Chance of precipitation in Spring
Williamstown gets around 10.9 in of rain and snow over 32 wet days across spring. The line is the day-by-day chance of measurable precipitation.
Humidity in Spring
Most of spring feels dry — the stacked bands show each day's mix of comfort levels, read off the dew point.
Wind in Spring
Winds average 8 mph across spring.
Sunrise & sunset in Spring
Daylight runs from about 11 hours in early March to 14 h 36 min by late May. The lit band spans sunrise to sunset each day.
Solar energy in Spring
Average shortwave solar energy reaching the ground each day across spring, about 5.0 kWh/m².
Hazard calendar for Williamstown
None of Williamstown's seasonal hazards peak in spring. The full-year calendar below shows when the rainy season, cyclone risk and dust haze do.
Williamstown sits in the Atlantic hurricane belt; the season peaks August–October.
Is spring a good time to visit Williamstown?
Our two travel scores rate spring for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal), averaged across the three months.
spring is a reasonable time to visit Williamstown for sightseeing.
What to pack for Williamstown in Spring
From spring's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In spring, Williamstown sees daytime highs around 63°F and nights near 46°F. Pack a warm layer. Worth having: light clothes, rain gear and sun protection. About 32 days see rain.
Sea temperature near Williamstown in Spring
The nearest coast averages about 49°F across spring — the other half of the beach question. The full-year curve and swim-comfort zones are below.
The sea at the nearest coast (about 39 mi away) is warmest in August at about 75°F and coldest in February near 38°F.
It's comfortable for a long swim from Jun 21 to Oct 3 — about 3.5 months when the water holds above 68°F.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sea temperature (°F) | 40 | 38 | 41 | 48 | 57 | 67 | 74 | 75 | 73 | 65 | 55 | 47 |
| Comfort | Bracing | Bracing | Bracing | Bracing | Bracing | Cool | Refreshing | Warm | Refreshing | Cool | Bracing | Bracing |
| Sea temperature (°F) | Comfort | |
|---|---|---|
| Jan | 40 | Bracing |
| Feb | 38 | Bracing |
| Mar | 41 | Bracing |
| Apr | 48 | Bracing |
| May | 57 | Bracing |
| Jun | 67 | Cool |
| Jul | 74 | Refreshing |
| Aug | 75 | Warm |
| Sep | 73 | Refreshing |
| Oct | 65 | Cool |
| Nov | 55 | Bracing |
| Dec | 47 | Bracing |
UV index in Williamstown in Spring
Clear-sky midday UV across spring averages around 6 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.
Under clear skies, the midday UV index in Williamstown peaks around July 11 at about 8 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 20 at about 2 (low).
The index reaches 3 or more — the level where the WHO recommends sun protection — in 8 months of the year.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 2 | 3 | 5 | 6 | 8 | 8 | 8 | 6 | 6 | 4 | 3 | 2 |
| Level | Low | Moderate | Moderate | High | Very high | Very high | Very high | High | High | Moderate | Moderate | Low |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 2 | Low |
| Feb | 3 | Moderate |
| Mar | 5 | Moderate |
| Apr | 6 | High |
| May | 8 | Very high |
| Jun | 8 | Very high |
| Jul | 8 | Very high |
| Aug | 6 | High |
| Sep | 6 | High |
| Oct | 4 | Moderate |
| Nov | 3 | Moderate |
| Dec | 2 | Low |
Air quality in Williamstown in Spring
Average fine-particle pollution (PM2.5) through the year — so you can see where spring falls, not just the annual average.
Air quality in Williamstown is worst in July — around 18 µg/m³ PM2.5 (moderate), about 2.0× the cleanest month (November, 9 µg/m³).
Modeled monthly averages (CAMS reanalysis, 2015–2024).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PM2.5 (µg/m³) | 11 | 13 | 15 | 13 | 15 | 16 | 18 | 15 | 12 | 9 | 9 | 10 |
| Level | Good | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Good | Good | Good | Good |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 11 | Good |
| Feb | 13 | Moderate |
| Mar | 15 | Moderate |
| Apr | 13 | Moderate |
| May | 15 | Moderate |
| Jun | 16 | Moderate |
| Jul | 18 | Moderate |
| Aug | 15 | Moderate |
| Sep | 12 | Good |
| Oct | 9 | Good |
| Nov | 9 | Good |
| Dec | 10 | Good |
Where is Williamstown?
Williamstown sits at 39.7°N, 75.0°W, 144 ft above sea level, in United States. The nearest listed city is Sicklerville, 2.5 mi away.
Topography around Williamstown
How much the land rises and falls, and what covers it, within 2, 10 and 50 miles of Williamstown.
Within 2 miles, the terrain around Williamstown has only modest variations in elevation — a maximum elevation change of 85 ft around an average of 151 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 233 ft; within 50 miles, significant variations in elevation — a maximum elevation change of 1,125 ft.
The land around Williamstown is covered by trees (60%) and grassland (23%) within 2 miles, trees (68%) within 10 miles, and trees (52%) and water (20%) within 50 miles.
United States travel facts
- Power plugs
- Type A / B
- 120 V · 60 Hz
- Prices
- ≈ 100% of US
- price level, 2025
- GDP per capita
- $90,027
- 2025
- Happiness
- 6.8 / 10
- World Happiness, 2025
- Safe drinking water
- 98%
- of population, 2024
- Homicide rate
- 5.8
- per 100k, 2023
- Road deaths
- 12.7
- per 100k/yr, 2019
- Income group
- High
- World Bank
- Religion
Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.
Data sources
Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Williamstown (39.6862°, -74.9952°, elevation 144 ft), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google.