Union County, IL Weather Forecast
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Chance Showers And Thunderstorms
Compare major city weather across Union County, scan the latest forecast snapshots, and jump into local 7-day outlook pages from one hub.
A chance of showers and thunderstorms before 2pm, then showers and thunderstorms likely. Partly sunny. High near 84, with temperatures falling to around 82 in the afternoon. West southwest wind 3 to 7 mph. Chance of precipitation is 70%.
County Weather Overview
This county weather page brings together forecast coverage for Union County so visitors can compare temperatures, wind, and conditions across the region without hopping between unrelated pages.
Current forecast coverage spans 2 of 2 mapped cities in Union County.
Page Snapshot
- Page focus
- county weather
- Forecast window
- Oct 14 to Oct 19, 2026
- Latest sync
- Oct 13, 2026 11:26 AM CDT
- Forecast office
- PAH
- Source
- NOAA / NWS
Daily Outlook
This Week in Union County
Thursday looks like the warmest upcoming period in Union County at 87 degrees F.
Saturday Night is the coolest period ahead with temperatures near 39 degrees F.
The strongest winds are forecast for Friday at about 15 to 20 mph NNW.
Precipitation is mentioned in 5 upcoming forecast periods.
Forecast Details
- Last updated
- Oct 13, 2026 11:26 AM CDT
- Coverage
- 6 days
- Time zone
- America/Chicago
- Forecast office
- PAH
- Radar station
- KPAH
Weather data is provided by the National Weather Service and refreshed automatically for U.S. locations.
Open NOAA sourceExtended Forecast
A chance of showers and thunderstorms before 10pm, then showers and thunderstorms likely. Mostly cloudy, with a low around 67. Northeast wind around 3 mph. Chance of precipitation is 70%.
Showers and thunderstorms likely before 7am, then a slight chance of showers and thunderstorms between 7am and 1pm, then a chance of showers and thunderstorms. Mostly sunny, with a high near 87. South wind 1 to 9 mph. Chance of precipitation is 70%.
A chance of showers and thunderstorms. Partly cloudy, with a low around 57. West wind 5 to 14 mph, with gusts as high as 22 mph. Chance of precipitation is 30%.
A slight chance of rain showers before 7am. Mostly sunny, with a high near 66. North northwest wind 15 to 20 mph, with gusts as high as 28 mph.
Mostly clear, with a low around 43. North wind 8 to 17 mph, with gusts as high as 25 mph.
Sunny, with a high near 63. Northeast wind 6 to 9 mph.
Clear, with a low around 39. East wind 1 to 5 mph.
Sunny, with a high near 70. South southeast wind 2 to 6 mph.
Partly cloudy, with a low around 48. South southeast wind around 3 mph.
Mostly sunny, with a high near 73. South wind around 6 mph.
Partly cloudy, with a low around 53. Southeast wind around 3 mph.
Detailed Forecast
| Period | Conditions | Temp | Wind |
|---|---|---|---|
|
Wednesday
Oct 14
|
Chance Showers And Thunderstorms
|
84°F |
3 to 7 mph
WSW
|
|
Wednesday Night
Oct 14
|
Chance Showers And Thunderstorms then Showers And Thunderstorms Likely
|
67°F |
3 mph
NE
|
|
Thursday
Oct 15
|
Showers And Thunderstorms Likely then Slight Chance Showers And Thunderstorms
|
87°F |
1 to 9 mph
S
|
|
Thursday Night
Oct 15
|
Chance Showers And Thunderstorms
|
57°F |
5 to 14 mph
W
|
|
Friday
Oct 16
|
Slight Chance Rain Showers then Mostly Sunny
|
66°F |
15 to 20 mph
NNW
|
|
Friday Night
Oct 16
|
Mostly Clear
|
43°F |
8 to 17 mph
N
|
|
Saturday
Oct 17
|
Sunny
|
63°F |
6 to 9 mph
NE
|
|
Saturday Night
Oct 17
|
Clear
|
39°F |
1 to 5 mph
E
|
|
Sunday
Oct 18
|
Sunny
|
70°F |
2 to 6 mph
SSE
|
|
Sunday Night
Oct 18
|
Partly Cloudy
|
48°F |
3 mph
SSE
|
|
Monday
Oct 19
|
Mostly Sunny
|
73°F |
6 mph
S
|
|
Monday Night
Oct 19
|
Partly Cloudy
|
53°F |
3 mph
SE
|
Major City Forecasts
Live forecast snapshots for major cities across Union County.
Coverage
Forecast coverage currently spans 2 of 2 mapped cities in Union County.
Largest mapped city population in this region: 4,059.