Climate · Union

Union, IN climate

Union has chilly winters and warm summers. A typical July afternoon reaches 88°, a January night drops to 25°, and about 12 inches of snow falls in a normal winter.

NOAA 1991-2020 climate normals Updated once a decade
July high
88°
1st hottest of 1,978 Indiana towns
January low
25°
7th mildest of 1,978 Indiana towns
Rain + melted snow
47 in
428th wettest of 1,978 Indiana towns
Snow a winter
12 in
234th least snowy of 1,972 Indiana towns
A normal year

What a year in Union feels like

Winter

45° / 28°
Typical high / low · 5 days with an inch or more of snow

Spring

67° / 46°
Typical high / low · Last frost around Apr 4

Summer

87° / 67°
Typical high / low · 40 days reach 90° in a normal year

Fall

69° / 48°
Typical high / low · First frost around Oct 29
Best months to be outsideAprMaySepOctHighs 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 days30-yr range
January42°25°3.3" 4.3"10 27° – 43°
February46°28°3.3" 3.2"9 26° – 45°
March57°36°4.5" 1.7"12 39° – 59°
April68°46°5.0" 012 51° – 62°
May77°57°4.9" 012 61° – 73°
June86°65°4.3" 010 71° – 80°
July88°69°4.3" 09 74° – 84°
August88°67°3.0" 07 72° – 83°
September82°59°3.4" 07 66° – 76°
October70°47°3.4" 0.2"8 54° – 64°
November56°37°3.9" 0.1"9 40° – 53°
December46°29°3.9" 2.9"10 24° – 47°
Year67°47°47.3"12.4"114

“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 47 inches of rain and melted snow a year. April is the wettest month and August the driest. Rain or snow falls on about 114 days a year.

47 in
Rain + melted snow a year
More rain than 78% of U.S. towns
12 in
Snow in a normal winter
Less snow than 69% of U.S. towns
114 days
With rain or snow (0.01"+)

Rain + melted snow by month

Inches of water
5.0"

Snowfall by month

Inches of snow
4.3"
Frost & the growing season

About 207 frost-free days a year

In half of years the last 32° night comes by April 4 and the first one by October 29. That leaves about 207 frost-free days for gardens, longer than 76% of U.S. towns.

86
nights at or below 32° in a normal year
1
nights below 0° in a normal year
40
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, 75% of that work is heating and 25% is cooling.

75%heating
4,299 heating degree daysLess heating than 76% of U.S. towns
1,463 cooling degree daysMore cooling than 78% 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 2 towns with climate data. January nights across them vary by 0.3°. Perry has the coldest January nights (25°) and Henderson the hottest July afternoons (88°). Union’s January low is 25° and its July high 88°.

German: January low 25°, July high 88°Marrs: January low 25°, July high 88°Pigeon: January low 25°, July high 88°Perry: January low 25°, July high 88°Henderson: January low 25°, July high 88°Union: January low 25°, July high 88° UnionPerryHenderson
ColderMilder25° to 25°
Perry25.0° −0.3°
Henderson25.1° −0.2°
Union25.3°

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 heat88° July high
Hotter than 73% of U.S. towns1st hottest of 1,978 Indiana towns
Winter cold25° January low
Milder than 73% of U.S. towns7th mildest of 1,978 Indiana towns
Precipitation47" a year
Wetter than 78% of U.S. towns428th wettest of 1,978 Indiana towns
Snow12" a winter
Less snow than 69% of U.S. towns234th least snowy of 1,972 Indiana towns
Growing season207 frost-free days
Longer than 76% of U.S. towns32nd longest 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

+0.7°1991–2020 average vs. the 20th century (1901–2000)

The last 30 years in Union averaged 0.7° warmer than the 1900s. The biggest change is in December (+1.5°). The shift is smaller than in 90% of U.S. towns.

❄️ Winter+1.1° now 36°, was 35°
🌷 Spring+0.8° now 57°, was 56°
☀️ Summer+0.3° now 77°, was 77°
🍂 Fall+0.5° now 58°, was 58°

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 24° to 47°. June is the most reliable, staying within 9°.

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 42° and a low of 25°.

What is the hottest month in Union?

July, with a typical high of 88° and a low of 69°. About 40 days a year reach 90°.

How much snow does Union get?

About 12 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 29, and the last spring frost by April 4.

What is the rainiest month in Union?

April, with 5.0 inches of rain and melted snow. The year totals 47 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 Henderson 8 Ssw, KY (8 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

Where to, neighbor?

You’re in Union, INVanderburgh CountyView boundary

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