Monthly climate in Union, Missouri, United States

Last updated: May 6, 2024

Under the Köppen–Geiger climate classification Union features a humid subtropical climate (Cfa).Temperatures typically range between 0 °C (33 °F) and 26 °C (79 °F) through the year, but rarely can drop to -20 °C (-5 °F) or can rise to as high as 39 °C (103 °F).The average annual precipitation amounts to about 1180 mm (46.4 inches) and receives 120 rainy days on the 1 mm (0.04 inches) threshold annually.Union enjoys an average of 2964 hours of sunshine throughout the year, and daylight varies from 9 hours 31 minutes to 14 hours 47 minutes per day.

Monthly average temperatures in Union, Missouri, United States §

The warmest months in Union are June, July and August, with daily mean temperatures ranging from 24 to 26 °C (76 - 79 °F) throughout the day. The coldest temperatures usually occur in January, February and December, when daily mean temperatures range from 0 to 4 °C (33 - 39 °F) throughout the day. On average each year, Union experiences 121 days above 25 °C (77.0 °F) and 75 days below 0 °C (32.0 °F).

Monthly average temperatures with daily means, minimums and maximums for period, average high and low temperatures in Union, Missouri, United States.Generated using Copernicus Climate Change Service information.Data for period from January 2017 to June 2022.
  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Maximum 20°C
(68°F)
25°C
(77°F)
29°C
(84°F)
31°C
(88°F)
34°C
(93°F)
37°C
(98°F)
39°C
(103°F)
36°C
(96°F)
35°C
(95°F)
33°C
(92°F)
25°C
(78°F)
23°C
(74°F)
Mean maximum 17°C
(63°F)
21°C
(70°F)
25°C
(77°F)
29°C
(84°F)
32°C
(89°F)
34°C
(93°F)
36°C
(98°F)
35°C
(95°F)
34°C
(93°F)
32°C
(89°F)
22°C
(73°F)
21°C
(69°F)
Average high 5°C
(41°F)
7°C
(46°F)
14°C
(57°F)
18°C
(65°F)
24°C
(76°F)
30°C
(85°F)
31°C
(89°F)
29°C
(85°F)
28°C
(83°F)
21°C
(69°F)
12°C
(55°F)
9°C
(49°F)
Daily mean 0°C
(33°F)
2°C
(36°F)
8°C
(47°F)
13°C
(55°F)
19°C
(66°F)
24°C
(76°F)
26°C
(79°F)
24°C
(76°F)
22°C
(72°F)
15°C
(59°F)
7°C
(45°F)
4°C
(39°F)
Average low -4°C
(26°F)
-3°C
(27°F)
4°C
(39°F)
7°C
(45°F)
14°C
(58°F)
19°C
(67°F)
22°C
(71°F)
19°C
(67°F)
17°C
(62°F)
10°C
(50°F)
2°C
(36°F)
-1°C
(31°F)
Mean minimum -15°C
(5°F)
-15°C
(6°F)
-8°C
(18°F)
-1°C
(30°F)
6°C
(44°F)
15°C
(59°F)
17°C
(63°F)
14°C
(58°F)
9°C
(49°F)
-0°C
(32°F)
-7°C
(19°F)
-10°C
(14°F)
Minimum -20°C
(-5°F)
-20°C
(-4°F)
-16°C
(3°F)
-4°C
(24°F)
4°C
(39°F)
12°C
(54°F)
15°C
(60°F)
13°C
(56°F)
8°C
(46°F)
-3°C
(26°F)
-14°C
(8°F)
-16°C
(4°F)

Compare climate in Union with other places

Compare temperature, precipitation, sunshine, UV index in Union, Missouri, United States with other places around the world.

Monthly average precipitation in Union, Missouri, United States §

Union usually has the most precipitation in March, May and August, with an average of 12 rainy days and 141 mm (5.6 inches) of precipitation per month.The driest months in Union are September, November and December. On average, 60 mm (2.3 inches) of precipitation falls during these months.

Monthly average precipitation and precipitation days in Union, Missouri, United States.Generated using Copernicus Climate Change Service information.Data for period from January 2017 to January 2022.
  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Average precipitation mm (inches) 75 (2.9) 80 (3.1) 126 (5.0) 126 (5.0) 152 (6.0) 89 (3.5) 100 (3.9) 145 (5.7) 55 (2.2) 108 (4.2) 69 (2.7) 54 (2.1)
Average precipitation days (≥ 1 mm) 7 10 11 13 14 11 10 13 6 11 8 6

Monthly sunshine hours in Union, Missouri, United States §

The sunniest months in Union are June, July and August, when the sun shines an average of 10 hours 50 minutes a day.Least sunny months in Union: January, February and December receive an average of 5 hours 31 minutes of sunshine daily.

Mean monthly sunshine duration, average sunshine hours per day and mean daily daylight hours in Union, Missouri, United States.Generated using Copernicus Atmosphere Monitoring Service information.Data for period from January 2017 to January 2022.
  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Mean monthly sunshine hours 128 177 207 239 281 323 347 325 287 236 212 196
Mean daily daylight hours 9h 48m 10h 46m 11h 58m 13h 13m 14h 16m 14h 47m 14h 30m 13h 34m 12h 22m 11h 8m 10h 3m 9h 31m

Solar UV radiation in Union, Missouri, United States §

Union experiences the highest level of ultraviolet (UV) radiation in June, July and August, when the maximum UV index can reach values of 10 - 11, which corresponds to the Very High / Extreme category of sun exposure.January, February and December are in the Moderate exposure category. In these months, the maximum values of the UV index do not exceed 5. For more detailed information, check out our hourly Union UV Index data.

Average daily maximum UV levels by month for Union, Missouri, United States.Generated using Copernicus Atmosphere Monitoring Service information.Data for period from January 2022 to January 2023.
  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
UV Index (month maximum) 3 5 6 9 10 11 11 10 9 7 5 3