Climate Comfort Score
63/100
Good
NOAA 1991–2020 normals 50°F annual avg Public-domain federal data
Chatham, MA Climate
Temperature, precipitation, and comfort score from NOAA NCEI 1991–2020 normals →
- 50°F
- Avg annual temp
- 63/100
- Comfort score
- 45.9"
- Annual precip
- 224d
- Growing season
30-year climate normals from 1 weather station (1991-2020).
The climate verdict for Chatham
Chatham, Massachusetts averages 50°F a year and scores 63/100 on the comfort index - good, milder than 47% of U.S. cities.
- 50°F
- annual average temperature (NOAA normal)
- 63/100
- comfort score, milder than 47% of U.S. cities
- 45.9"
- annual precipitation · 25" snow
- 224 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
50°F (10°C)
Avg High
57°F
Avg Low
44°F
Annual Precip
45.9"
Annual Snow
24.5"
Comfort Score
63/100
Good
Avg Annual Temperature
50°F
30-year mean (NOAA NCEI)
Annual Precipitation
45.9"
Plus 24.5" of snow
Comfort score vs national 100-point ceiling (Chatham) 63.0%
National median (63)
PlainClimate composite, temperature mildness, humidity, precipitation, extreme-weather frequency. Good for the Chatham area.
How Chatham compares to every U.S. city
Chatham's comfort score vs. all U.S. cities
PlainClimate composite comfort index (1–100), NOAA 1991–2020 normals
63 Top 53% higher than 47% 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 Chatham
MethodologyHow the U.S. land temperature anomaly tracks against the global mean since 1900. The current NOAA 1991-2020 normal for Chatham captures average conditions across the spread shown, the most recent decade is 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 | Snow | Freeze Days | 90°F+ Days |
|---|---|---|---|---|---|---|---|
| January | 39°F (4°C) | 25°F (-4°C) | 32°F (0°C) | 4.0" | 7.5" | 23.4 | 0.0 |
| February | 39°F (4°C) | 25°F (-4°C) | 32°F (0°C) | 3.8" | 9.9" | 21.1 | 0.0 |
| March | 43°F (6°C) | 31°F (-1°C) | 37°F (3°C) | 4.7" | 3.8" | 15.9 | 0.0 |
| April | 51°F (11°C) | 40°F (4°C) | 45°F (7°C) | 4.0" | 0.5" | 2.1 | 0.0 |
| May | 60°F (15°C) | 48°F (9°C) | 54°F (12°C) | 3.3" | 0.0" | 0.0 | 0.0 |
| June | 69°F (21°C) | 57°F (14°C) | 63°F (17°C) | 3.2" | 0.0" | 0.0 | 0.1 |
| July | 76°F (24°C) | 63°F (17°C) | 70°F (21°C) | 2.8" | 0.0" | 0.0 | 0.0 |
| August | 76°F (24°C) | 63°F (17°C) | 69°F (21°C) | 3.2" | 0.0" | 0.0 | 0.0 |
| September | 70°F (21°C) | 58°F (15°C) | 64°F (18°C) | 3.8" | 0.0" | 0.0 | 0.0 |
| October | 61°F (16°C) | 49°F (9°C) | 55°F (13°C) | 4.3" | 0.0" | 0.0 | 0.0 |
| November | 52°F (11°C) | 40°F (4°C) | 46°F (8°C) | 4.1" | 0.2" | 4.8 | 0.0 |
| December | 44°F (7°C) | 31°F (0°C) | 38°F (3°C) | 4.7" | 2.6" | 15.8 | 0.0 |
Monthly Precipitation
Average monthly rainfall and snowfall
January 4.0"
Snow: 7.5"
12.4 days with precipitation
February 3.8"
Snow: 9.9"
10.9 days with precipitation
March 4.7"
Snow: 3.8"
11.7 days with precipitation
April 4.0"
Snow: 0.5"
11.5 days with precipitation
May 3.3"
11.0 days with precipitation
June 3.2"
9.6 days with precipitation
July 2.8"
8.2 days with precipitation
August 3.2"
8.3 days with precipitation
September 3.8"
8.7 days with precipitation
October 4.3"
10.8 days with precipitation
November 4.1"
Snow: 0.2"
10.6 days with precipitation
December 4.7"
Snow: 2.6"
12.9 days with precipitation
Frost Dates & Growing Season
First Fall Freeze
November 15
50% probability date
Last Spring Freeze
April 5
50% probability date
Growing Season
224 days
Heating & Cooling Degree Days
Annual totals indicate energy demand for heating and cooling
Heating Degree Days
5,681
Higher = more heating needed
Cooling Degree Days
369
Higher = more cooling needed
Warmest Month
July
Coldest Month
January
What Chatham's climate means for you
Chatham runs 50°F a year - peaking in July, coldest in January.
- Gardeners get about 224 frost-free days, with the last spring freeze near April 5 - plan the planting calendar around it, not the regional average.
- Energy bills track 5,681 heating and 369 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: Chatham, MA
An annual average temperature of 50°F, ranging from a mean daily high of 57°F to a mean daily low of 44°F is what the NOAA 1991–2020 climate normals report for Chatham, Massachusetts. July is typically the warmest month of the year, while January is the coldest. That baseline comes from station USC00191386 and thirty years of averaging, so it reflects a typical month rather than any one year's swings.
Beyond temperature, Chatham averages 45.9 inches of precipitation annually, with 24.5 inches typically falling as snow - a real factor for anyone planning to live, garden, or travel here. The frost-free season averages 224 days, which directly shapes the planting calendar and growing potential for the area, with the last spring freeze near April 5 and the first fall freeze near November 15. Turning to energy use, 5,681 heating degree days and 369 cooling degree days tell the story of how often furnaces and air conditioners run during a normal year.
On PlainClimate's composite comfort index, Chatham scores 63/100 (Good), a blended measure that weighs temperature mildness, precipitation moderation, and extreme-weather frequency against one another. For planning purposes, look to the monthly tables above: shoulder seasons bring the mildest highs and lows, summer brings July-driven heat, and deep winter brings January-driven cold. Treat every figure here as a thirty-year average rather than a forecast - individual years routinely run warmer, cooler, wetter, or drier than the normal.
Frequently Asked Questions
What is the average temperature in Chatham, MA? ▼
The average annual temperature in Chatham, Massachusetts is 50°F. The warmest month averages 76°F (24°C) and the coldest averages 25°F (-4°C).
How much rain does Chatham get? ▼
Chatham receives 45.9 inches of precipitation annually, including 24.5 inches of snow. Based on NOAA 30-year climate normals (1991-2020).
What is the comfort score for Chatham? ▼
Chatham has a climate comfort score of 63/100 (Good), milder than 47% of U.S. cities in the PlainClimate database.
When is the growing season in Chatham? ▼
Chatham has approximately 224 frost-free days per year, with the last spring freeze around April 5 and the first fall freeze around November 15.
How much energy does heating and cooling require in Chatham? ▼
Chatham has 5,681 heating degree days and 369 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 Chatham climate data come from? ▼
NOAA U.S. Climate Normals v1.0.1 (1991-2020), from weather station USC00191386 near Chatham.
Data Sources
Data source: NOAA U.S. Climate Normals v1.0.1 (1991-2020). Station: USC00191386. 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.