Climate · Union

Union, IN climate

Union has chilly winters and warm summers. A typical July afternoon reaches 84°, a January night drops to 20°, and about 17 inches of snow falls in a normal winter.

NOAA 1991-2020 climate normals Updated once a decade
July high
84°
966th hottest of 1,978 Indiana towns
January low
20°
786th mildest of 1,978 Indiana towns
Rain + melted snow
45 in
722nd wettest of 1,978 Indiana towns
Snow a winter
17 in
707th least snowy of 1,972 Indiana towns
A normal year

What a year in Union feels like

Winter

39° / 23°
Typical high / low · 6 days with an inch or more of snow

Spring

63° / 42°
Typical high / low · Last frost around Apr 20

Summer

83° / 63°
Typical high / low · 18 days reach 90° in a normal year

Fall

65° / 44°
Typical high / low · First frost around Oct 19
Best months to be outsideAprMayJunAugSepOctHighs of 62–84° and lows of 40° or more
Month by month

Union 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
January36°20°3.1" 6.3"109 20° – 39°
February41°24°2.6" 4.2"98 20° – 42°
March51°32°3.6" 2.2"102 34° – 55°
April64°41°4.7" 0.1"120 46° – 58°
May73°52°5.0" 0120 57° – 71°
June81°61°5.0" 0110 66° – 74°
July84°64°4.2" 0100 69° – 82°
August83°62°3.3" 070 68° – 78°
September78°55°3.2" 070 62° – 71°
October66°43°3.4" 0.1"80 50° – 60°
November52°33°3.6" 0.2"90 36° – 49°
December40°25°3.1" 3.8"104 20° – 42°
Year62°43°44.6"16.9"11422

“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 Union

Union gets 45 inches of rain and melted snow a year. May is the wettest month and February the driest. Rain or snow falls on about 114 days a year. Snow covers the ground about 22 days of the year.

45 in
Rain + melted snow a year
More rain than 67% of U.S. towns
17 in
Snow in a normal winter
Less snow than 62% of U.S. towns
22 days
With 1"+ of snow on the ground
Fewer than 56% of U.S. towns

Rain + melted snow by month

Inches of water
5.0"

Snowfall by month

Inches of snow
6.3"
Frost & the growing season

About 180 frost-free days a year

In half of years the last 32° night comes by April 20 and the first one by October 19. That leaves about 180 frost-free days for gardens, longer than 53% of U.S. towns.

117
nights at or below 32° in a normal year
4
nights below 0° in a normal year
18
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 Union

Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Union, 87% of that work is heating and 13% is cooling, so the furnace matters far more than the air conditioner.

87%heating
5,752 heating degree daysMore heating than 50% of U.S. towns
897 cooling degree daysMore cooling than 54% 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 Union

Union and its neighbors

Union borders 4 towns with climate data. January nights across them vary by 0.7°. White River has the coldest January nights (20°) and Green the hottest July afternoons (85°). Union’s January low is 20° and its July high 84°.

Clay: January low 21°, July high 85°Jackson: January low 21°, July high 84°Harrison: January low 21°, July high 85°Washington: January low 21°, July high 85°Nineveh: January low 21°, July high 85°Hamblen: January low 21°, July high 84°Morgantown: January low 21°, July high 85°Bargersville: January low 20°, July high 85°Indianapolis: January low 20°, July high 85°Perry: January low 20°, July high 85°Madison: January low 20°, July high 85°Pleasant: January low 20°, July high 85°Greenwood: January low 20°, July high 85°Needham: January low 21°, July high 85°Green: January low 21°, July high 85°Hensley: January low 21°, July high 84°White River: January low 20°, July high 84°Franklin: January low 20°, July high 84°Union: January low 20°, July high 84° UnionGreenHensleyWhite RiverFranklin
ColderMilder20° to 21°
White River19.9° −0.1°
Union20.0°
Franklin20.2° +0.2°
Hensley20.5° +0.5°
Green20.6° +0.6°

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

Compared with other towns

How Union compares

Summer heat84° July high
Cooler than 54% of U.S. towns966th hottest of 1,978 Indiana towns
Winter cold20° January low
Milder than 54% of U.S. towns786th mildest of 1,978 Indiana towns
Precipitation45" a year
Wetter than 67% of U.S. towns722nd wettest of 1,978 Indiana towns
Snow17" a winter
Less snow than 62% of U.S. towns707th least snowy of 1,972 Indiana towns
Growing season180 frost-free days
Longer than 53% of U.S. towns988th shortest of 1,978 Indiana towns

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

Then and now

Warmer than it used to be

+0.9°1991–2020 average vs. the 20th century (1901–2000)

The last 30 years in Union averaged 0.9° warmer than the 1900s. The biggest change is in December (+2.2°). The shift is smaller than in 77% of U.S. towns.

❄️ Winter+1.7° now 31°, was 29°
🌷 Spring+1.2° now 52°, was 51°
☀️ Summer+0.0° now 73°, was 73°
🍂 Fall+0.6° now 54°, was 54°

Change by month1991–2020 average minus 1901–2000 average, at Union’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. December swings the most: between 1991 and 2020 its average temperature ranged from 20° to 42°. June is the most reliable, staying within 8°.

Coldest to warmest month in 30 yearsNormal
Questions

Common questions about Union’s climate

What is the coldest month in Union?

January, with a typical high of 36° and a low of 20°.

What is the hottest month in Union?

July, with a typical high of 84° and a low of 64°. About 18 days a year reach 90°.

How much snow does Union get?

About 17 inches in a normal winter, most of it in January.

When is the first frost in Union?

In half of years the first 32° night comes by October 19, and the last spring frost by April 20.

What is the rainiest month in Union?

May, with 5.0 inches of rain and melted snow. The year totals 45 inches.

Temperatures and rainfall come from NOAA’s gridded climate normals for Union itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Franklin WWTP, IN (9 mi) away. Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000.

The porch light’s on

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