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Penobscot County Climate

JanFebMarAprMayJunJulAugSepOctNovDec43.3°AVG °F

Avg Annual Temp

43.3°F

Annual Precip

43.8"

Annual Snowfall

77.4"

Extreme Heat Days

4

days >= 90°F/yr

Monthly Temperature

54.4°F avgJFMAMJJASOND

Precipitation Calendar

Dry
Wet= snowfall
3.2"
2.6"
3.3"
3.7"
3.5"
4.1"
3.6"
3.6"
3.7"
4.6"
4.0"
3.9"
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Growing Season & Gardening

USDA Hardiness Zone

5a

Minimum winter temperature range for plant survival

Growing Degree Days

1,963

Favors cool-season crops

Last spring frost (32°F): 05/08
First fall frost (32°F): 10/04

Seasonal Overview

Comfort ZoneSpring28°53°10.5"Summer63°68°11.3"Fall36°58°12.3"Winter16°24°9.7"20°40°60°80°100°

National Comparison

Warmer than 8% of US counties
Wetter than 55% of US counties
More seasonal variation than 87% of US counties

7-Day Outlook

Forecast

Current Conditions

Air Quality

Safety

Weather Alerts

Climate Advisory: Penobscot County

Climate Verdict

Penobscot County has a cool, averaging 43.3°F annually, moderately wet with 43.8 inches of annual precipitation, rare extreme heat with only 4.475 days above 90°F annually, heavy winter snowfall averaging 77.4 inches per year. This climate profile shapes everything from energy costs to outdoor recreation opportunities.

Seasonal Breakdown

Winters are very cold — January averages 16.1°F. summers are pleasantly cool with July averaging 68.3°F. Residents experience a substantial 52°F difference between winter and summer.

Outdoor & Gardening Guidance

Winter sports enthusiasts benefit from reliable snow cover for 3-4 months annually.

Regional Context

Penobscot County closely matches the Maine statewide average temperature of 43.8°F, it is somewhat drier than average for Maine.

Climate Profile

About Penobscot County Weather

Penobscot's brisk northern character

With an annual average of 43.3°F, Penobscot County is over 10 degrees cooler than the median U.S. county. Its climate features the sharp seasonal shifts typical of the humid continental North.

Mirroring the state average

The county's 43.3°F average closely tracks the overall Maine state average of 43.8°F. It serves as a representative middle ground between the state's frigid interior and warmer coast.

Milder than its northern neighbors

Penobscot enjoys a warmer profile than Piscataquis County, which averages only 41.8°F. It also receives about 12 inches less annual snowfall than the 89.9 inches seen in Piscataquis.

Cold winters and short heatwaves

January temperatures average 16.1°F, contributing to a substantial 77.4 inches of annual snowfall. The county typically experiences 4 days of extreme heat above 90°F during the July peak.

Equipping for the Penobscot seasons

Homeowners prioritize winterization and insulation to combat the 19.6°F average winter temperature. Reliable snow tires are essential for navigating the nearly 80 inches of annual accumulation.

Frequently Asked Questions

What is the average temperature in Penobscot County?
The average annual temperature in Penobscot County, ME is 43.3°F, based on NOAA 30-year climate normals (1991-2020).
How much rain does Penobscot County get?
Penobscot County receives an average of 43.8 inches of precipitation per year, including both rain and meltwater from snow. This is based on NOAA 30-year climate normals.
Does it snow in Penobscot County?
Yes, Penobscot County receives an average of 77.4 inches of snowfall per year according to NOAA climate normals.
How hot does Penobscot County get in summer?
The average summer temperature (June-August) in Penobscot County is 65.9°F. The county experiences an average of 4 days per year above 90°F.
How cold are winters in Penobscot County?
The average winter temperature (December-February) in Penobscot County is 19.6°F. January, typically the coldest month, averages 16.1°F.

Track your own weather in Penobscot County

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Data sources: NOAA National Centers for Environmental Information (NCEI), U.S. Climate Normals 1991-2020. Forecast and alert data from National Weather Service API. Air quality data from Open-Meteo.

Climate normals are 30-year averages of weather variables. Station data is aggregated to county level. Forecasts and alerts are fetched live and may change frequently. Data is informational only — not a substitute for official National Weather Service forecasts or emergency weather warnings.

By Evan Brooks, Data EditorUpdated Reviewed by Evan Brooks, Data Editor
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