Frost & Freeze Decision Support Page

*** Frost & Freeze Headlines Have Ended for the Fall Season ***

Current Frost & Freeze Headlines

Freeze Watch		Latest Regional Watches, Warnings, & Advisories
Freeze Warning
Frost Advisory

Observations
Forecast
Climatology (Spring)
Climatology (Fall)
Additional Frost & Freeze Information

Observations

Observed 24-Hour Low Temperatures
National Weather Service St. Louis
Date of Most Recent Hard Freeze	Date of Most Recent Freeze
Midwest Regional Climate Center	Midwest Regional Climate Center

Forecast

Forecast Low Temperatures Day 1
National Weather Service St. Louis
Forecast Low Temperatures Day 2	Forecast Low Temperatures Day 3
National Weather Service St. Louis	National Weather Service St. Louis
Forecast Low Temperatures Day 4	Forecast Low Temperatures Day 5
National Weather Service St. Louis	National Weather Service St. Louis
Forecast Low Temperatures Day 6	Forecast Low Temperatures Day 7
National Weather Service St. Louis	National Weather Service St. Louis
6–10 Day Temperature Outlook	8–14 Day Temperature Outlook
Climate Prediction Center	Climate Prediction Center

Climatology (Spring)

				Last Hard Freeze (≤28ºF)				Last Freeze (≤32ºF)				Last Frost (≤36ºF)
Location	ID	Type	State	Earliest	Median	Average	Latest	Earliest	Median	Average	Latest	Earliest	Median	Average	Latest
St. Louis	KSTL	ASOS	MO	2/11 1878	3/26	3/20	4/24 1910	2/26 1878	4/2	4/2	5/10 1966	3/22 2017	4/12	4/11	5/11 1907
Columbia	KCOU	ASOS	MO	3/5 2010	3/29	3/29	5/4 1907	3/10 1929	4/8	4/8	5/9 1906	3/29 1941	4/22	4/22	5/25 1925
Quincy	KUIN	ASOS	IL	3/5 2012	4/1	4/1	5/10 1966	3/10 1929	4/11	4/12	5/10 1966	4/4 1915	4/28	4/28	5/26 1901
Chesterfield	KSUS	ASOS	MO	3/6 2010	4/1	3/31	4/24 2023	3/16 2017	4/11	4/11	5/6 1992	4/1 1991	4/23	4/24	5/17 2011
Cahokia*	KCPS	ASOS	IL	3/5 2012	3/26	3/24	4/17 2018	3/10 2012	4/9	4/8	4/29 2008	3/30 1999	4/21	4/22	5/13 2021
St. Charles*	KSET	ASOS	MO	3/6 2016	3/24	3/24	4/9 2007	3/19 2017	4/10	4/8	4/24 2023	3/22 2017	4/18	4/20	5/10 2021
Jefferson City	KJEF	ASOS	MO	3/5 2010	3/24	3/24	5/3 1967	3/15 2017	4/12	4/10	5/27 1961	4/3 1895	4/23	4/24	5/30 1947
Farmington*	KFAM	ASOS	MO	3/7 1977	4/2	4/4	5/10 1969	3/24 1977	4/10	4/13	5/27 1961	4/6 2002	4/23	4/23	5/30 1947
Belleville SIU Res.	SIUI2	COOP	IL	3/7 1977	3/31	4/1	5/4 1976	3/19 2017	4/11	4/10	5/9 1980	3/23 2017	4/24	4/26	5/18 2002
Hillsboro*	HLBI2	COOP	IL	3/5 2012	3/30	3/29	5/25 1925	3/20 2005	4/12	4/9	5/25 1925	4/1 2017	4/23	4/25	5/31 1930
Jerseyville	JVLI2	COOP	IL	3/7 1977	4/3	4/4	5/4 1976	3/23 2017	4/13	4/13	5/17 1973	4/1 2017	4/27	4/27	5/27 1961
Ramsey	RAMI2	COOP	IL	3/17 2005	4/3	4/4	4/22 2021	3/28 1999	4/14	4/14	5/5 2005	3/31 1991	4/25	4/28	5/27 1992
Salem	SLOI2	COOP	IL	3/7 2010	3/29	3/27	4/24 1963	3/10 2012	4/9	4/7	5/12 1960	3/31 2010	4/20	4/21	5/18 2002
White Hall	WHLI2	COOP	IL	3/6 2012	4/3	4/1	5/4 1976	3/23 2017	4/13	4/12	5/25 1925	3/29 1941	4/23	4/25	6/16 1917
California	CALM7	COOP	MO	3/5 2010	4/4	4/1	4/24 1956	3/16 2017	4/9	4/9	5/4 1913	4/6 1981	4/21	4/23	5/18 2002
Elsberry	EBYM7	COOP	MO	3/5 2012	4/5	4/3	5/1 1950	3/27 1999	4/18	4/18	5/25 1934	4/9 1985	4/27	4/29	5/30 1947
Hannibal WP	HNNM7	COOP	MO	3/6 2012	3/29	3/30	4/24 1956	3/10 2012	4/10	4/11	5/10 1966	3/29 1941	4/16	4/18	5/25 1925
Jefferson City WP	JWPM7	COOP	MO	3/3 2016	3/25	3/24	5/3 1967	3/10 2012	4/5	4/4	4/27 1961	3/17 2017	4/16	4/17	5/30 1947
Rosebud*	RSEM7	COOP	MO	3/16 2017	4/12	4/11	5/4 2005	4/3 1992	4/23	4/25	5/18 2018	4/15 1981	5/8	5/7	5/30 2021
Medians and averages based on 1991–2020 climatological data. *More than 5 years with seasons including more than 5 days with missing data—use with caution.

Hard Freeze (≤28ºF)
Earliest	Median	Latest
Midwest Regional Climate Center	Midwest Regional Climate Center	Midwest Regional Climate Center
Freeze (≤32ºF)
Earliest	Median	Latest
Midwest Regional Climate Center	Midwest Regional Climate Center	Midwest Regional Climate Center

Climatology (Fall)

				First Hard Freeze (≤28ºF)				First Freeze (≤32ºF)				First Frost (≤36ºF)
Location	ID	Type	State	Earliest	Median	Average	Latest	Earliest	Median	Average	Latest	Earliest	Median	Average	Latest
St. Louis	KSTL	ASOS	MO	10/18 1976	11/15	11/15	12/14 1923	9/28 1942	11/1	11/2	11/27 2009	9/23 1974	10/21	10/23	11/26 1902
Columbia	KCOU	ASOS	MO	9/30 1899	11/1	11/3	12/8 1998	9/18 1901	10/22	10/23	11/20 2015	9/13 1902	10/13	10/14	11/10 2016
Quincy	KUIN	ASOS	IL	9/28 1942	10/31	10/31	11/29 1983	9/26 1928	10/19	10/20	11/22 1944	9/12 1940	10/11	10/11	11/7 1956
Chesterfield	KSUS	ASOS	MO	10/9 2000	10/31	10/31	11/22 1994	9/23 1995	10/21	10/19	11/10 2016	9/21 1991	10/7	10/9	10/28 2007
Cahokia*	KCPS	ASOS	IL	10/9 2000	11/1	11/2	11/29 2024	10/5 2020	10/21	10/21	11/12 2016	9/25 2001	10/12	10/12	11/10 2016
St. Charles*	KSET	ASOS	MO	10/16 2020	11/2	11/6	12/3 2009	10/2 2003	10/18	10/22	11/10 2016	9/22 1999	10/11	10/11	11/2 2021
Jefferson City	KJEF	ASOS	MO	10/2 1987	11/1	11/2	11/29 1990	9/25 1989	10/26	10/23	11/24 1944	9/13 1902	10/13	10/14	11/8 1956
Farmington*	KFAM	ASOS	MO	9/22 1995	10/28	10/26	11/25 2004	9/8 1956	10/21	10/18	11/7 1940	9/5 1907	10/8	10/9	11/1 1918
Belleville SIU Res.	SIUI2	COOP	IL	9/23 1995	10/27	10/26	11/26 1958	9/20 1991	10/14	10/14	11/10 2016	9/7 1988	10/9	10/8	11/8 1956
Hillsboro*	HLBI2	COOP	IL	9/26 1928	11/3	11/6	12/9 2001	9/21 1991	10/18	10/18	11/11 2011	9/11 1917	10/12	10/12	11/10 2016
Jerseyville	JVLI2	COOP	IL	9/23 1983	10/29	10/28	11/26 2024	9/21 1991	10/17	10/16	11/10 2016	9/8 1986	10/10	10/7	10/29 1963
Ramsey	RAMI2	COOP	IL	9/23 1995	10/28	10/27	11/25 2004	9/20 1991	10/13	10/14	11/10 2016	9/15 2007	10/6	10/6	11/1 2021
Salem	SLOI2	COOP	IL	10/3 1974	11/4	11/6	12/4 2009	10/2 1985	10/26	10/25	11/26 2024	9/21 1991	10/14	10/14	11/10 2016
White Hall	WHLI2	COOP	IL	9/28 1942	10/28	10/28	11/26 2024	9/20 1918	10/17	10/18	11/24 1944	9/8 1986	10/9	10/9	11/6 1947
California	CALM7	COOP	MO	10/9 200	11/1	11/3	11/29 1983	9/30 1984	10/26	10/23	11/13 2016	9/19 1991	10/16	10/16	11/10 2016
Elsberry	EBYM7	COOP	MO	9/28 1942	10/31	10/30	11/26 2024	9/17 1937	10/17	10/16	11/8 1956	9/12 1955	10/10	10/8	11/1 1973
Hannibal WP	HNNM7	COOP	MO	10/6 1952	11/3	11/6	11/29 1994	9/26 1928	10/28	10/27	11/23 2024	9/9 1999	10/13	10/12	11/8 1956
Jefferson City WP	JWPM7	COOP	MO	10/2 1987	11/8	11/11	12/9 2001	9/25 1989	10/28	10/27	11/24 1944	9/13 1902	10/17	10/17	11/10 2016
Rosebud*	RSEM7	COOP	MO	9/22 1983	10/26	10/24	11/10 2016	9/22 1983	10/13	10/12	11/6 2016	9/15 1999	10/4	10/3	10/22 2025
Medians and averages based on 1991–2020 climatological data. *More than 5 years with seasons including more than 5 days with missing data—use with caution.

Hard Freeze (≤28ºF)
Earliest	Median	Latest
Midwest Regional Climate Center	Midwest Regional Climate Center	Midwest Regional Climate Center
Freeze (≤32ºF)
Earliest	Median	Latest
Midwest Regional Climate Center	Midwest Regional Climate Center	Midwest Regional Climate Center

Additional Frost & Freeze Information

Frost & Freeze Definitions

Frost	Thin ice that forms on surfaces when the temperature falls to or below 32ºF and sufficient moisture is available, which can damage many seasonal plants and kill some sensitive seasonal plants during prolonged exposure. Conventional temperature measurements above the surface often only need to be at or below 36ºF for frost to form.
Freeze	When the temperature falls to or below 32ºF, which can significantly damage nearly all seasonal plants and even kill many seasonal plants during prolonged exposure. A freeze can occur without the development of frost.
Hard Freeze	When the temperature falls to or below 28ºF, which can kill nearly all seasonal plants. A hard freeze can occur without the development of frost.

How Does Frost Form?