Climate · Union

Union, IN climate

Union has chilly winters and warm summers. A typical July afternoon reaches 84°, a January night drops to 18°, and about 28 inches of snow falls in a normal winter.

NOAA 1991-2020 climate normals Updated once a decade
July high
84°
907th coolest of 1,978 Indiana towns
January low
18°
701st coldest of 1,978 Indiana towns
Rain + melted snow
40 in
371st driest of 1,978 Indiana towns
Snow a winter
28 in
439th snowiest of 1,972 Indiana towns
A normal year

What a year in Union feels like

Winter

36° / 21°
Typical high / low · 11 days with an inch or more of snow

Spring

60° / 39°
Typical high / low · Last frost around Apr 23

Summer

82° / 61°
Typical high / low · 18 days reach 90° in a normal year

Fall

63° / 43°
Typical high / low · First frost around Oct 19
Best months to be outsideMayJunAugSepOctHighs 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
January33°18°2.6" 9.2"1114 16° – 37°
February37°21°2.1" 7.5"911 16° – 39°
March48°29°2.7" 4.2"114 30° – 53°
April61°39°3.9" 0.5"130 43° – 56°
May72°50°4.6" 0130 54° – 67°
June81°60°4.3" 0120 65° – 74°
July84°63°4.3" 0100 69° – 79°
August82°61°4.0" 090 67° – 77°
September76°53°3.1" 080 61° – 69°
October64°43°2.9" 0100 49° – 60°
November50°33°3.0" 1.2"102 34° – 48°
December38°24°2.4" 5.5"118 18° – 41°
Year60°41°39.8"28.1"12738

“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 40 inches of rain and melted snow a year. May is the wettest month and February the driest. Rain or snow falls on about 127 days a year. Snow covers the ground about 38 days of the year.

40 in
Rain + melted snow a year
More rain than 50% of U.S. towns
28 in
Snow in a normal winter
More snow than 54% of U.S. towns
38 days
With 1"+ of snow on the ground
More than 58% of U.S. towns

Rain + melted snow by month

Inches of water
4.6"

Snowfall by month

Inches of snow
9.2"
Frost & the growing season

About 178 frost-free days a year

In half of years the last 32° night comes by April 23 and the first one by October 19. That leaves about 178 frost-free days for gardens, longer than 50% of U.S. towns.

127
nights at or below 32° in a normal year
6
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, 88% of that work is heating and 12% is cooling, so the furnace matters far more than the air conditioner.

88%heating
6,010 heating degree daysMore heating than 56% of U.S. towns
818 cooling degree daysLess cooling than 52% 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 3 towns with climate data. January nights across them vary by 0.3°. Root has the coldest January nights (18°) and Monroe the hottest July afternoons (84°). Union’s January low is 18° and its July high 84°.

Washington: January low 19°, July high 84°Preble: January low 19°, July high 84°Madison: January low 18°, July high 84°Blue Creek: January low 19°, July high 84°Willshire: January low 19°, July high 84°Jackson: January low 18°, July high 84°Root: January low 18°, July high 84°St. Marys: January low 19°, July high 84°Monroe: January low 18°, July high 84°Union: January low 18°, July high 84° UnionRootSt. MarysMonroe
ColderMilder18° to 19°
Union18.3°
Root18.3° same
Monroe18.3° same
St. Marys18.6° +0.3°

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 56% of U.S. towns907th coolest of 1,978 Indiana towns
Winter cold18° January low
Colder than 55% of U.S. towns701st coldest of 1,978 Indiana towns
Precipitation40" a year
Wetter than 50% of U.S. towns371st driest of 1,978 Indiana towns
Snow28" a winter
Snowier than 54% of U.S. towns439th snowiest of 1,972 Indiana towns
Growing season178 frost-free days
Longer than 50% of U.S. towns814th 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

+1.3°1991–2020 average vs. the 20th century (1901–2000)

The last 30 years in Union averaged 1.3° warmer than the 1900s. The biggest change is in December (+2.5°). The shift is larger than in 56% of U.S. towns.

❄️ Winter+2.0° now 28°, was 26°
🌷 Spring+1.4° now 50°, was 48°
☀️ Summer+0.7° now 72°, was 71°
🍂 Fall+1.1° now 53°, was 52°

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. March swings the most: between 1991 and 2020 its average temperature ranged from 30° to 53°. September 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 33° and a low of 18°.

What is the hottest month in Union?

July, with a typical high of 84° and a low of 63°. About 18 days a year reach 90°.

How much snow does Union get?

About 28 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 23.

What is the rainiest month in Union?

May, with 4.6 inches of rain and melted snow. The year totals 40 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 Decatur 1 N, IN (5 mi) away. Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000.

The coffee’s on

Where to, neighbor?

You’re in Union, INAdams CountyView boundary

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