Climate · Bethlehem

Bethlehem, CT climate

Bethlehem has chilly, snowy winters and pleasant summers, with plenty of rain. A typical July afternoon reaches 81°, a January night drops to 15°, and about 47 inches of snow falls in a normal winter.

NOAA 1991-2020 climate normals Updated once a decade
July high
81°
28th coolest of 364 Connecticut towns
January low
15°
28th coldest of 364 Connecticut towns
Rain + melted snow
50 in
99th wettest of 364 Connecticut towns
Snow a winter
47 in
135th snowiest of 353 Connecticut towns
A normal year

What a year in Bethlehem feels like

Winter

36° / 18°
Typical high / low · 14 days with an inch or more of snow

Spring

57° / 35°
Typical high / low · Last frost around May 8

Summer

79° / 57°
Typical high / low · 7 days reach 90° in a normal year

Fall

60° / 40°
Typical high / low · First frost around Oct 5
Best months to be outsideMayJunJulAugSepHighs of 62–84° and lows of 40° or more
Month by month

Bethlehem weather by month

Average highs, lows, rain and snow for every month, from NOAA’s 1991–2020 normals.

MonthHighLowRain + meltSnowWet daysSnow on ground30-yr range
January34°15°3.6" 11.3"1215 16° – 31°
February37°17°3.0" 13.7"1015 13° – 33°
March45°25°4.0" 10.3"129 28° – 44°
April57°35°4.0" 1.4"101 41° – 50°
May68°45°3.9" 0120 52° – 62°
June76°54°4.6" 0110 62° – 69°
July81°60°4.5" 0100 65° – 74°
August79°58°4.5" 090 65° – 72°
September72°51°4.5" 0100 58° – 66°
October61°40°4.8" 090 46° – 56°
November49°31°3.9" 1.5"101 35° – 44°
December38°22°4.3" 8.6"119 23° – 41°
Year58°37°49.5"46.8"12549

“Wet days” have at least 0.01" of rain or melted snow. “Snow on ground” counts days with 1" or more. The 30-year range is the coldest and warmest that month’s average temperature got between 1991 and 2020.

Rain & snow

Rain and snow in Bethlehem

Bethlehem gets 50 inches of rain and melted snow a year. October is the wettest month and February the driest. Rain or snow falls on about 125 days a year. Snow covers the ground about 49 days of the year.

50 in
Rain + melted snow a year
More rain than 86% of U.S. towns
47 in
Snow in a normal winter
More snow than 78% of U.S. towns
49 days
With 1"+ of snow on the ground
More than 65% of U.S. towns

Rain + melted snow by month

Inches of water
4.8"

Snowfall by month

Inches of snow
14"
Frost & the growing season

About 151 frost-free days a year

In half of years the last 32° night comes by May 8 and the first one by October 5. That leaves about 151 frost-free days for gardens, shorter than 80% of U.S. towns.

158
nights at or below 32° in a normal year
8
nights below 0° in a normal year
7
days that reach 90° in a normal year

Freezing nights by month

Average nights at or below 32°

90° days by month

Average days at 90° or more
Heating & cooling

Heating and cooling a home in Bethlehem

Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Bethlehem, 94% of that work is heating and 6% is cooling, so the furnace matters far more than the air conditioner.

94%heating
6,841 heating degree daysMore heating than 71% of U.S. towns
431 cooling degree daysLess cooling than 82% of U.S. towns

Degree days measure how far each day’s average temperature falls below or rises above 65°, added up over a year. Source: NOAA station normals.

Around Bethlehem

Bethlehem and its neighbors

Bethlehem borders 4 towns with climate data. January nights across them vary by 1.5°. Morris has the coldest January nights (15°) and Woodbury the hottest July afternoons (83°). Bethlehem’s January low is 15° and its July high 81°.

New Milford: January low 17°, July high 84°Roxbury: January low 17°, July high 83°Warren: January low 15°, July high 80°Kent: January low 15°, July high 81°Litchfield: January low 15°, July high 81°Thomaston: January low 16°, July high 82°Middlebury: January low 17°, July high 83°Southbury: January low 18°, July high 84°Waterbury: January low 18°, July high 83°Washington: January low 16°, July high 82°Morris: January low 15°, July high 81°Woodbury: January low 17°, July high 83°Watertown: January low 17°, July high 83°Bethlehem: January low 15°, July high 81° BethlehemWashingtonMorrisWoodburyWatertown
ColderMilder15° to 18°
Morris15.3° −0.1°
Bethlehem15.4°
Washington15.7° +0.3°
Watertown16.5° +1.1°
Woodbury16.8° +1.4°

Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value.

Compared with other towns

How Bethlehem compares

Summer heat81° July high
Cooler than 80% of U.S. towns28th coolest of 364 Connecticut towns
Winter cold15° January low
Colder than 68% of U.S. towns28th coldest of 364 Connecticut towns
Precipitation50" a year
Wetter than 86% of U.S. towns99th wettest of 364 Connecticut towns
Snow47" a winter
Snowier than 78% of U.S. towns135th snowiest of 353 Connecticut towns
Growing season151 frost-free days
Shorter than 80% of U.S. towns27th shortest of 364 Connecticut towns

Compared with every U.S. town and city on TownTapestry, each counted once.

Then and now

Warmer than it used to be

+1.7°1991–2020 average vs. the 20th century (1901–2000)

The last 30 years in Bethlehem averaged 1.7° warmer than the 1900s. The biggest change is in December (+3.3°). The shift is larger than in 83% of U.S. towns.

❄️ Winter+2.6° now 27°, was 25°
🌷 Spring+1.4° now 46°, was 44°
☀️ Summer+1.6° now 68°, was 66°
🍂 Fall+1.4° now 50°, was 49°

Change by month1991–2020 average minus 1901–2000 average, at Bethlehem’s spot on NOAA’s grid

Year to year

How much a month can swing

A normal is an average, and real years wander around it. February swings the most: between 1991 and 2020 its average temperature ranged from 13° to 33°. June is the most reliable, staying within 6°.

Coldest to warmest month in 30 yearsNormal
Questions

Common questions about Bethlehem’s climate

What is the coldest month in Bethlehem?

January, with a typical high of 34° and a low of 15°.

What is the hottest month in Bethlehem?

July, with a typical high of 81° and a low of 60°. About 7 days a year reach 90°.

How much snow does Bethlehem get?

About 47 inches in a normal winter, most of it in February.

When is the first frost in Bethlehem?

In half of years the first 32° night comes by October 5, and the last spring frost by May 8.

What is the rainiest month in Bethlehem?

October, with 4.8 inches of rain and melted snow. The year totals 50 inches.

Temperatures and rainfall come from NOAA’s gridded climate normals for Bethlehem itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Woodbury, CT (6 mi, snow) and Bakersville, CT (18 mi, frost, heat and degree days). Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000.

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