Climate Comfort Score
64/100
Good
NOAA 1991–2020 normals 51°F annual avg Public-domain federal data
Somerville, NJ Climate
Pulled from NOAA NCEI 1991–2020 normals →: average temperature, precipitation, and comfort score
- 51°F
- Avg annual temp
- 64/100
- Comfort score
- 46.7"
- Annual precip
- 173d
- Growing season
30-year climate normals from 1 weather station (1991-2020).
The climate verdict for Somerville
Somerville, New Jersey averages 51°F a year and scores 64/100 on the comfort index - good, milder than 51% of U.S. cities.
- 51°F
- yearly average temperature, NOAA normal
- 64/100
- comfort score, milder than 51% of U.S. cities
- 46.7"
- precipitation, annual total
- 173 days
- growing season, frost-free days
Based on NOAA U.S. Climate Normals (1991–2020) - 30-year averages describing the typical year, not a forecast.
Avg Temperature
51°F (11°C)
Avg High
63°F
Avg Low
40°F
Annual Precip
46.7"
Comfort Score
64/100
Good
Avg Annual Temperature
51°F
30-year mean (NOAA NCEI)
Annual Precipitation
46.7"
Liquid-equivalent total
Comfort score vs national 100-point ceiling (Somerville) 64.0%
National median (63)
PlainClimate composite, temperature mildness, humidity, precipitation, extreme-weather frequency. Good for the Somerville area.
How Somerville compares to every U.S. city
Somerville's comfort score vs. all U.S. cities
PlainClimate composite comfort index (1–100), NOAA 1991–2020 normals
64 Top 49% higher than 51% of 6,915 US cities
Each bar is a band; taller bars hold more US cities. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count, share, and where it sits relative to this entry.
Source NOAA U.S. Climate Normals, PlainClimate comfort index · 1991–2020
Warming context for Somerville
MethodologySince 1900, U.S. land temperatures have tracked (and diverged from) the global mean - the chart below shows how. Somerville's current NOAA 1991-2020 normal sits within that longer spread, and the most recent decade runs warmer than the 30-year mean.
- United States land mean (NOAA NCEI) +0.11 °C/decade
- Global anomaly (NASA GISTEMP) +0.11 °C/decade
- Paris Agreement thresholds 1.5°C / 2.0°C
Monthly Temperatures
Average daily high and low temperatures by month
| Month | Avg High | Avg Low | Mean | Precip | Freeze Days | 90°F+ Days |
|---|---|---|---|---|---|---|
| January | 39°F (4°C) | 19°F (-7°C) | 29°F (-2°C) | 3.5" | 27.9 | 0.0 |
| February | 41°F (5°C) | 20°F (-7°C) | 30°F (-1°C) | 2.8" | 25.4 | 0.0 |
| March | 50°F (10°C) | 27°F (-3°C) | 38°F (4°C) | 4.1" | 22.7 | 0.0 |
| April | 62°F (17°C) | 36°F (2°C) | 49°F (10°C) | 4.0" | 9.8 | 0.1 |
| May | 72°F (22°C) | 46°F (8°C) | 59°F (15°C) | 3.4" | 1.1 | 0.8 |
| June | 81°F (27°C) | 56°F (13°C) | 68°F (20°C) | 4.3" | 0.0 | 3.3 |
| July | 86°F (30°C) | 62°F (17°C) | 74°F (23°C) | 4.7" | 0.0 | 7.0 |
| August | 83°F (29°C) | 60°F (16°C) | 72°F (22°C) | 3.7" | 0.0 | 4.4 |
| September | 77°F (25°C) | 53°F (12°C) | 65°F (18°C) | 4.3" | 0.0 | 0.7 |
| October | 64°F (18°C) | 41°F (5°C) | 53°F (12°C) | 4.3" | 6.4 | 0.0 |
| November | 54°F (12°C) | 31°F (0°C) | 42°F (6°C) | 3.2" | 18.1 | 0.0 |
| December | 43°F (6°C) | 24°F (-4°C) | 34°F (1°C) | 4.4" | 25.3 | 0.0 |
Monthly Precipitation
Average monthly rainfall
January 3.5"
11.2 days with precipitation
February 2.8"
9.2 days with precipitation
March 4.1"
11.7 days with precipitation
April 4.0"
11.7 days with precipitation
May 3.4"
11.9 days with precipitation
June 4.3"
10.1 days with precipitation
July 4.7"
10.2 days with precipitation
August 3.7"
9.7 days with precipitation
September 4.3"
8.7 days with precipitation
October 4.3"
8.2 days with precipitation
November 3.2"
8.6 days with precipitation
December 4.4"
11.2 days with precipitation
Frost Dates & Growing Season
First Fall Freeze
October 20
50% probability date
Last Spring Freeze
April 30
50% probability date
Growing Season
173 days
Heating & Cooling Degree Days
Annual totals indicate energy demand for heating and cooling
Heating Degree Days
5,769
Higher = more heating needed
Cooling Degree Days
748
Higher = more cooling needed
Warmest Month
July
Coldest Month
January
What Somerville's climate means for you
Somerville runs 51°F a year - peaking in July, coldest in January.
- Gardeners get about 173 frost-free days, with the last spring freeze near April 30 - plan the planting calendar around it, not the regional average.
- Energy bills track 5,769 heating and 748 cooling degree days a year, higher means the furnace or AC runs more.
- Comparing places to live? Line this city up against nearby cities and the national rankings. See rankings
These are 30-year NOAA normals (1991–2020) - the typical year, not a forecast for any specific season.
Climate Guides
Climate Insight: Somerville, NJ
Somerville, New Jersey runs an annual average of 51°F, ranging from a mean daily high of 63°F to a mean daily low of 40°F, per NOAA's 1991–2020 climate normals. July is typically the warmest month of the year, while January is the coldest. Drawn from station USC00288194, these thirty-year averages smooth out year-to-year swings into a baseline for what a typical month looks like here.
Anyone planning to live, garden, or travel in Somerville should weigh precipitation alongside temperature: the annual average runs 46.7 inches, predominantly as rainfall. The frost-free season averages 173 days, which directly shapes the planting calendar and growing potential for the area, with the last spring freeze near April 30 and the first fall freeze near October 20. And on the energy front, 5,769 heating degree days and 748 cooling degree days tell the story of how often furnaces and air conditioners run during a normal year.
On PlainClimate's composite comfort index, Somerville scores 64/100 (Good), a blended measure that weighs temperature mildness, precipitation moderation, and extreme-weather frequency against one another. The monthly tables above are the practical planning tool: mild highs and lows land in the shoulder seasons, July-driven heat peaks in summer, and January-driven cold sets in over deep winter. These are thirty-year averages, not a forecast - any single year can run warmer, wetter, drier, or cooler than the normal.
Frequently Asked Questions
What is the average temperature in Somerville, NJ? ▼
The average annual temperature in Somerville, New Jersey is 51°F. The warmest month averages 86°F (30°C) and the coldest averages 19°F (-7°C).
How much rain does Somerville get? ▼
Somerville receives 46.7 inches of precipitation annually. Based on NOAA 30-year climate normals (1991-2020).
What is the comfort score for Somerville? ▼
Somerville has a climate comfort score of 64/100 (Good), milder than 51% of U.S. cities in the PlainClimate database.
When is the growing season in Somerville? ▼
Somerville has approximately 173 frost-free days per year, with the last spring freeze around April 30 and the first fall freeze around October 20.
How much energy does heating and cooling require in Somerville? ▼
Somerville has 5,769 heating degree days and 748 cooling degree days annually, a heating-dominated climate. See our <a href="/guides/reading-weather-data/" class="underline hover:text-brand-600">guide to reading weather data</a> for what these figures mean.
Where does this Somerville climate data come from? ▼
NOAA U.S. Climate Normals v1.0.1 (1991-2020), from weather station USC00288194 near Somerville.
Data Sources
Data source: NOAA U.S. Climate Normals v1.0.1 (1991-2020). Station: USC00288194. For informational purposes only.
Read our methodology - how this data is sourced, computed, and verified.
Related
Data sourced from official public datasets. See our methodology for details. Retrieved and formatted by PlainClimate Editorial
Every figure on PlainClimate is rendered directly from NOAA 1991-2020 U.S. Climate Normals data, no number is typed in by an editor. This page draws directly on NOAA 1991-2020 U.S. Climate Normals data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.