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Westport Island, ME Climate

Temperature, precipitation, and comfort score from NOAA NCEI 1991-2020 normals →

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

Westport Island, Maine has an average annual temperature of 46°F and a climate comfort score of 57/100 (Moderate). Annual precipitation totals 51.7". Based on NOAA 30-year normals (1991–2020).

Avg Temperature

46°F (8°C)

Avg High

54°F

Avg Low

38°F

Annual Precip

51.7"

Comfort Score

57/100

Moderate

Climate Comfort Score

57/100

Moderate

Avg Annual Temperature

46°F

30-year mean (NOAA NCEI)

Annual Precipitation

51.7"

Liquid-equivalent total

Comfort score vs national 100-point ceiling (Westport Island) 57.0%
National median (≈55)

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

Warming context for Westport Island

Methodology

How the U.S. land temperature anomaly tracks against the global mean since 1900. The current NOAA 1991-2020 normal for Westport Island captures average conditions across the spread shown — the most recent decade is 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 31°F (-1°C) 14°F (-10°C) 23°F (-5°C)
February 33°F (1°C) 16°F (-9°C) 25°F (-4°C)
March 41°F (5°C) 24°F (-4°C) 32°F (0°C)
April 51°F (11°C) 34°F (1°C) 43°F (6°C)
May 63°F (17°C) 44°F (7°C) 53°F (12°C)
June 70°F (21°C) 53°F (12°C) 62°F (17°C)
July 76°F (25°C) 59°F (15°C) 68°F (20°C)
August 76°F (24°C) 59°F (15°C) 67°F (20°C)
September 69°F (21°C) 51°F (11°C) 60°F (16°C)
October 58°F (14°C) 42°F (5°C) 50°F (10°C)
November 47°F (8°C) 32°F (0°C) 40°F (4°C)
December 37°F (3°C) 22°F (-6°C) 29°F (-1°C)

Monthly Precipitation

Average monthly rainfall

January 4.4"

12.5 days with precipitation

February 3.9"

10.1 days with precipitation

March 4.9"

11.2 days with precipitation

April 4.3"

11.8 days with precipitation

May 3.6"

14.7 days with precipitation

June 4.4"

15.7 days with precipitation

July 3.7"

12.3 days with precipitation

August 3.2"

11.7 days with precipitation

September 4.3"

9.0 days with precipitation

October 5.2"

13.8 days with precipitation

November 4.3"

12.5 days with precipitation

December 5.4"

12.8 days with precipitation

Frost Dates & Growing Season

First Fall Freeze

October 21

50% probability date

Last Spring Freeze

April 28

50% probability date

Heating & Cooling Degree Days

Annual totals indicate energy demand for heating and cooling

Heating Degree Days

7,165

Higher = more heating needed

Cooling Degree Days

265

Higher = more cooling needed

Warmest Month

July

Coldest Month

January

Related Data

Climate Guides

Climate Insight: Westport Island, ME

The NOAA 1991–2020 climate normals describe Westport Island, Maine as a location with an annual average temperature of 46°F, ranging from a mean daily high of 54°F to a mean daily low of 38°F. July is typically the warmest month of the year, while January is the coldest. These thirty-year averages, computed from station USC00179547, smooth out year-to-year variability and give a baseline expectation for typical conditions in any given month.

Precipitation patterns matter as much as temperature for anyone planning to live, garden, or travel here. Westport Island receives roughly 51.7 inches of precipitation each year, predominantly as rainfall. Growing-season length varies with elevation and microclimate, with the last spring freeze near April 28 and the first fall freeze near October 21. For energy use, 7,165 heating degree days and 265 cooling degree days tell the story of how often furnaces and air conditioners run during a normal year.

On PlainClimate's composite comfort index, Westport Island scores 57/100 (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 Westport Island, ME?
The average annual temperature in Westport Island, Maine is 46°F. The warmest month averages 76°F (25°C) and the coldest averages 14°F (-10°C).
How much rain does Westport Island get?
Westport Island receives 51.7 inches of precipitation annually. Based on NOAA 30-year climate normals (1991-2020).
What is the comfort score for Westport Island?
Westport Island has a climate comfort score of 57/100 (Moderate). This score considers temperature mildness, humidity, precipitation, and extreme weather frequency.
When is the growing season in Westport Island?
Growing season data is not available for Westport Island.
How much energy does heating and cooling require in Westport Island?
Westport Island has 7,165 heating degree days and 265 cooling degree days annually. Higher heating degree days indicate greater winter energy demand, while higher cooling degree days indicate greater summer cooling needs.
Where does this Westport Island climate data come from?
All climate data comes from NOAA U.S. Climate Normals v1.0.1, covering the 30-year period from 1991 to 2020. Data is collected from weather station USC00179547. These 30-year averages are the standard reference for typical weather conditions.

Data Sources

Data source: NOAA U.S. Climate Normals v1.0.1 (1991-2020). Station: USC00179547. For informational purposes only.

Related

Data sourced from official public datasets. See our methodology for details. Retrieved and formatted by PlainClimate Editorial