PlainClimate
NOAA 1991–2020 normals 44°F annual avg Public-domain federal data

Belfast, ME Climate

Pulled from NOAA NCEI 1991–2020 normals →: average temperature, precipitation, and comfort score

44°F
Avg annual temp
44/100
Comfort score
48.8"
Annual precip
151d
Growing season

30-year climate normals from 1 weather station (1991-2020).

The climate verdict for Belfast

Belfast, Maine averages 44°F a year and scores 44/100 on the comfort index - moderate, milder than 8% of U.S. cities.

44°F
annual average temperature (NOAA normal)
44/100
comfort score, milder than 8% of U.S. cities
48.8"
annual precipitation · 72" snow
151 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

44°F (7°C)

Avg High

54°F

Avg Low

34°F

Annual Precip

48.8"

Annual Snow

71.5"

Comfort Score

44/100

Moderate

Climate Comfort Score

44/100

Moderate

Avg Annual Temperature

44°F

30-year mean (NOAA NCEI)

Annual Precipitation

48.8"

Plus 71.5" of snow

Comfort score vs national 100-point ceiling (Belfast) 44.0%
National median (63)

PlainClimate composite, temperature mildness, humidity, precipitation, extreme-weather frequency. Moderate for the Belfast area.

How Belfast compares to every U.S. city

Belfast's comfort score vs. all U.S. cities

PlainClimate composite comfort index (1–100), NOAA 1991–2020 normals

44 Top 92% higher than 8% of 6,915 US cities

0–10: 0 US cities (0%). Below this entry. 10–20: 0 US cities (0%). Below this entry. 20–30: 58 US cities (1%). Below this entry. 30–40: 439 US cities (6%). Below this entry. 40–50: 1,302 US cities (19%). This entry sits in this band. 50–60: 1,433 US cities (21%). Above this entry. 60–70: 1,357 US cities (20%). Above this entry. 70–80: 1,102 US cities (16%). Above this entry. 80–90: 778 US cities (11%). Above this entry. 90–100: 420 US cities (6%). Above this entry. This city 0 100 every U.S. city, bucketed by value

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 Belfast

Methodology

Since 1900, U.S. land temperatures have tracked (and diverged from) the global mean - the chart below shows how. Belfast's current NOAA 1991-2020 normal sits within that longer spread, and the most recent decade runs warmer than the 30-year mean.

Warming context, U.S. vs global, with Paris reference lines Anomaly chart from 1900 to 2024. Local series shows warming of 0.11 °C per decade versus a global rate of 0.11 °C per decade (ratio 1.00). Paris Agreement thresholds at 1.5 and 2.0 °C are dashed. -1.0°C -0.5°C +0.0°C +0.5°C +1.0°C +1.5°C +2.0°C +2.5°C Paris 1.5°C Paris 2.0°C 1900192019401960198020002020
  • 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
Sources: NOAA NCEI, NASA GISTEMP. Paris thresholds per IPCC AR6 WG1.

Monthly Temperatures

Average daily high and low temperatures by month

Month Avg High Avg Low Mean
January 30°F (-1°C) 10°F (-12°C) 20°F (-7°C)
February 32°F (0°C) 12°F (-11°C) 22°F (-6°C)
March 40°F (4°C) 20°F (-6°C) 30°F (-1°C)
April 52°F (11°C) 31°F (0°C) 41°F (5°C)
May 63°F (17°C) 41°F (5°C) 52°F (11°C)
June 72°F (22°C) 51°F (10°C) 61°F (16°C)
July 77°F (25°C) 57°F (14°C) 67°F (19°C)
August 76°F (25°C) 56°F (13°C) 66°F (19°C)
September 70°F (21°C) 48°F (9°C) 59°F (15°C)
October 57°F (14°C) 38°F (3°C) 48°F (9°C)
November 46°F (8°C) 29°F (-2°C) 37°F (3°C)
December 35°F (2°C) 18°F (-8°C) 27°F (-3°C)

Monthly Precipitation

Average monthly rainfall and snowfall

January 3.9"

Snow: 19.2"

8.8 days with precipitation

February 3.2"

Snow: 22.4"

7.3 days with precipitation

March 4.1"

Snow: 11.7"

7.9 days with precipitation

April 4.4"

Snow: 2.2"

9.5 days with precipitation

May 3.9"

9.7 days with precipitation

June 4.3"

9.7 days with precipitation

July 3.2"

8.5 days with precipitation

August 3.1"

7.7 days with precipitation

September 4.1"

7.4 days with precipitation

October 5.4"

Snow: 0.3"

9.5 days with precipitation

November 4.7"

Snow: 2.5"

9.2 days with precipitation

December 4.7"

Snow: 13.2"

10.1 days with precipitation

Frost Dates & Growing Season

First Fall Freeze

October 5

50% probability date

Last Spring Freeze

May 7

50% probability date

Growing Season

151 days

Heating & Cooling Degree Days

Annual totals indicate energy demand for heating and cooling

Heating Degree Days

7,785

Higher = more heating needed

Cooling Degree Days

204

Higher = more cooling needed

Warmest Month

July

Coldest Month

January

What Belfast's climate means for you

Belfast runs 44°F a year - peaking in July, coldest in January.

  • Gardeners get about 151 frost-free days, with the last spring freeze near May 7 - plan the planting calendar around it, not the regional average.
  • Energy bills track 7,785 heating and 204 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: Belfast, ME

Based on station USC00170480 feeding NOAA's 1991–2020 climate normals, Belfast, Maine averages 44°F a year, ranging from a mean daily high of 54°F to a mean daily low of 34°F. July is typically the warmest month of the year, while January is the coldest. Because these figures are thirty-year averages rather than any single year's readings, they describe the typical month, not a forecast for it.

Beyond temperature, Belfast averages 48.8 inches of precipitation annually, with 71.5 inches typically falling as snow - a real factor for anyone planning to live, garden, or travel here. The frost-free season averages 151 days, which directly shapes the planting calendar and growing potential for the area, with the last spring freeze near May 7 and the first fall freeze near October 5. Turning to energy use, 7,785 heating degree days and 204 cooling degree days tell the story of how often furnaces and air conditioners run during a normal year.

On PlainClimate's composite comfort index, Belfast scores 44/100 (Moderate), a blended measure that weighs temperature mildness, precipitation moderation, and extreme-weather frequency against one another. Use the monthly tables above to plan around specific windows, shoulder seasons for mild highs and lows, peak summer for July-driven heat, or deep winter for January-driven cold. All figures here are thirty-year averages: any single year may run warmer, wetter, drier, or cooler than the normal, so treat them as planning guidance rather than forecasts.

Frequently Asked Questions

What is the average temperature in Belfast, ME?
The average annual temperature in Belfast, Maine is 44°F. The warmest month averages 77°F (25°C) and the coldest averages 10°F (-12°C).
How much rain does Belfast get?
Belfast receives 48.8 inches of precipitation annually, including 71.5 inches of snow. Based on NOAA 30-year climate normals (1991-2020).
What is the comfort score for Belfast?
Belfast has a climate comfort score of 44/100 (Moderate), milder than 8% of U.S. cities in the PlainClimate database.
When is the growing season in Belfast?
Belfast has approximately 151 frost-free days per year, with the last spring freeze around May 7 and the first fall freeze around October 5.
How much energy does heating and cooling require in Belfast?
Belfast has 7,785 heating degree days and 204 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 Belfast climate data come from?
NOAA U.S. Climate Normals v1.0.1 (1991-2020), from weather station USC00170480 near Belfast.

Data Sources

Data source: NOAA U.S. Climate Normals v1.0.1 (1991-2020). Station: USC00170480. For informational purposes only.

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.