Union County climate

Union County Weather in August

NOAA 1991-2020 normals for Grenville, 18.2 km from Union County

Average highs run from 85°F on August 1 to 82°F on August 31, and lows from 58°F to 55°F. Normal precipitation for the month is 3.15 in over about 9 wet days.

August day by day

The normal high and low for each date, and the record, in °F.

Normal daily high and low temperature at Union County, in °F, with the record for each date.406080100120151015202530
  • Normal low
  • Normal high
  • Record high
  • Record low

August at a glance

Average high
84°F
Average low
57°F
Precipitation
3.15 in
Record high
102°FAug 3, 1944
Record low
42°FAug 23, 1910
Chance of a freeze
0%
Days of 90°F or more
7.2
Daylight
14 h 00 min to 12 h 58 min
Cloud cover
47%
Humidity
54%
Dew point
51°F
Wind
9.4 mph

Every day of the month

A wet day has at least 0.01 inch of precipitation; snow means at least 0.1 inch of snowfall.

DateNormal highNormal lowRecord highRecord lowChance wetChance of snow
Aug 185°F58°F101°F 194450°F 197132%0%
Aug 285°F58°F100°F 194446°F 197332%0%
Aug 385°F58°F102°F 194450°F 192732%0%
Aug 485°F58°F100°F 192649°F 192832%0%
Aug 585°F58°F99°F 192652°F 192831%0%
Aug 685°F58°F100°F 202552°F 191731%0%
Aug 785°F58°F102°F 202548°F 193931%0%
Aug 885°F58°F101°F 202548°F 193931%0%
Aug 984°F57°F99°F 202151°F 191530%0%
Aug 1084°F57°F100°F 193748°F 192730%0%
Aug 1184°F57°F102°F 201249°F 192730%0%
Aug 1284°F57°F102°F 193650°F 192929%0%
Aug 1384°F57°F100°F 193650°F 192029%0%
Aug 1484°F57°F100°F 191149°F 192029%0%
Aug 1584°F57°F98°F 191152°F 191528%0%
Aug 1684°F57°F97°F 195250°F 191928%0%
Aug 1784°F57°F98°F 192448°F 192727%0%
Aug 1883°F57°F99°F 200246°F 195027%0%
Aug 1983°F57°F99°F 191149°F 195027%0%
Aug 2083°F56°F102°F 200748°F 195026%0%
Aug 2183°F56°F99°F 200748°F 192026%0%
Aug 2283°F56°F99°F 191045°F 192025%0%
Aug 2383°F56°F99°F 192242°F 191025%0%
Aug 2483°F56°F100°F 192242°F 192824%0%
Aug 2583°F56°F96°F 193646°F 192824%0%
Aug 2683°F55°F99°F 200248°F 191423%0%
Aug 2782°F55°F98°F 192947°F 199223%0%
Aug 2882°F55°F101°F 192244°F 191722%0%
Aug 2982°F55°F98°F 192243°F 192822%0%
Aug 3082°F55°F99°F 192243°F 191522%0%
Aug 3182°F55°F98°F 201144°F 191821%0%

Chance of rain

The chance of at least 0.01 inch of precipitation on each date at Union County, in percent, and of at least 0.1 inch of snowfall.0102030401102030
  • Chance of a wet day
  • Chance of snowfall

Sunrise and sunset

Times for 2026, local time (MDT).

August 1
sunrise 6:00 AM, sunset 8:00 PM
August 31
sunrise 6:25 AM, sunset 7:23 PM

Every day of August: sun and moon

Other months

Sources

Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00293706 (Grenville), public domain. Records: NOAA GHCN-Daily, station USW00023051, every year on file, quality-flagged values removed. Cloud, humidity, wind and sunshine: NASA POWER (MERRA-2, CERES and GEWEX SRB), 1991-2020. The data was obtained from the National Aeronautics and Space Administration (NASA) Langley Research Center's Prediction Of Worldwide Energy Resources (POWER) project funded through the NASA Earth Science Division: POWER Daily API v2, accessed 2026-09-24. Sun and moon: computed with the NOAA solar equations and Meeus.