Union County, Illinois · Frost dates
Union County frost dates.
First-frost, last-frost, and growing-season length for Union County, Illinois. Sourced from NOAA 1991-2020 Climate Normals.
Data confidence: high · USDA zone: 6a
32°F — light freeze
Last spring frost
- 10%
- 04-26
- 20%
- 04-20
- 50%
- 04-08
- 80%
- 03-29
- 90%
- 03-22
First fall frost
- 10%
- 10-17
- 20%
- 10-21
- 50%
- 10-29
- 80%
- 11-05
- 90%
- 11-10
28°F — killing freeze
Last spring freeze
- 10%
- 04-16
- 20%
- 04-08
- 50%
- 03-29
- 80%
- 03-17
- 90%
- 03-10
First fall freeze
- 10%
- 10-27
- 20%
- 11-01
- 50%
- 11-08
- 80%
- 11-19
- 90%
- 11-25
Growing season length (days, 28°F threshold)
- Short year
- 194
- Median
- 224
- Long year
- 260
Source NOAA station
ANNA 2 NNE, IL US
0.6 mi · 30 yrs of record (1991–2020) · 640 ft elev.
Data from ANNA 2 NNE, IL US, 0.6 miles away with 30-year NOAA record (1991-2020).
Bield Farm earns its predictions.
14-day free trial. No credit card. Cancel anytime.