Average first frost/freeze period nears

COLUMBUS (WCMH) – We have officially entered into fall, and the month of October, the period where temperatures start to make the turn downward. This is also the month where many of us start to see our first frost or freeze.

I took this picture above last year, and put the date on, because I wanted to make sure I remembered next year (now) when we had our first frost last season. I also took a picture of my thermometer, which read a morning low of 34°.It is important to note, the first frost and freeze are not the same thing. So why can we have frost above 32°?

On generally clear nights, with no wind and a cooler airmass in place this time of the year, it makes for ideal conditions for cooling. As we know from taking a hot shower, the warm/moist air is lighter than the cold/dry air, and it will rise. The heavier cold air will sink down to the near the ground. Weather instruments for official reporting are taken approximately 5 feet above the ground.

So on a cold night, the official temperature for a location might read as warm as 35° or 36°, yet there will be frost on the ground below where the temperature is at or below freezing (32°).

It is also important to note, that we can have a freeze without a frost in dry conditions.When do we normally see our first freeze?

This is something we keep track of for several reporting cities in our area, and the short answer is, it depends. But in general most cities see their first freeze in the month of October.

According to the National Weather Service in Wilmington, our average first freeze date in Columbus is one of the latest in Central and southern Ohio (October 27th).

The NWS has listed some of our other cities that they have data for, and their first freeze dates:

Bellefontaine		14-Oct
Chillicothe		17-Oct
Circleville		19-Oct
Delaware		14-Oct
Kenton		20-Oct
London		9-Oct
Marysville		22-Oct
Newark		12-Oct
Washington Court House		21-Oct

While the normal for first freeze dates in Columbus is October 27th, we have had a wide range of dates:

The earliest have been in late September, and the latest dates (like last year) well into November. Last year marked only the 2nd time that we had our first freeze date on November 10th. In fact, there were only 10 years were the 1st freeze were later than we had last year.

Are we expecting a frost or freeze anytime soon here in Central Ohio?

No, not in the next week! We are going to continue to stay quite warm over the next week. We have a cold front that will arrive late Sunday into Monday morning. But this front is only going to bring temperatures back to normal. This means highs in the mid/upper 60s and lows in the lower to middle 40s. Hardly frost range.

Also, below is the 6-10 day outlook from the Climate Prediction Center at NOAA. It shows very good chances that temperatures will remain above normal during this period.

The 8-14 day outlook from the Climate Prediction Center at NOAA does not show much chance for below normal temperatures either.

If this outlook does hold, it means most locations in Central Ohio will be past their average first freeze date. At this point it is way too soon to say if we are going to see record late dates, and in fact, we would have to get past Thanksgiving to do so.How long will frost/freeze warnings be issued?

The National Weather Service offices are the ones that issue these warnings, and they are mainly for agricultural interests. In general the NWS will issues these warnings either until a county has had a widespread hard freeze, or a specific date has been reached. For most areas that date in November 1st, but there are a few counties from Franklin county down south along US-23 and the southern part of the state that warnings can be issued until the end of the first week of November.Here is a complete list since 1878 of all the first freeze dates for Columbus:

year	month	date
2016	nov	10
2015	oct	17
2014	nov	2
2013	oct	25
2012	oct	11
2011	oct	29
2010	oct	30
2009	oct	18
2008	oct	22
2007	nov	23
2006	oct	15
2005	oct	29
2004	nov	9
2003	oct	3
2002	nov	1
2001	oct	18
2000	oct	29
1999	oct	25
1998	oct	23
1997	oct	21
1996	nov	2
1995	oct	17
1994	oct	28
1993	oct	23
1992	oct	17
1991	oct	16
1990	oct	26
1989	oct	9
1988	oct	6
1987	oct	4
1986	nov	3
1985	nov	8
1984	nov	2
1983	oct	27
1982	oct	17
1981	oct	3
1980	oct	6
1979	oct	14
1978	oct	17
1977	oct	16
1976	oct	17
1975	oct	3
1974	oct	2
1973	nov	4
1972	oct	19
1971	nov	4
1970	oct	16
1969	oct	15
1968	oct	5
1967	oct	20
1966	oct	21
1965	oct	5
1964	oct	6
1963	sep	30
1962	sep	21
1961	sep	29
1960	oct	21
1959	oct	18
1958	oct	29
1957	oct	20
1956	nov	13
1955	oct	25
1954	oct	20
1953	oct	30
1952	oct	4
1951	oct	9
1950	oct	26
1949	oct	27
1948	oct	18
1947	nov	9
1946	nov	18
1945	nov	3
1944	nov	5
1943	nov	4
1942	oct	26
1941	nov	9
1940	nov	7
1939	oct	15
1938	oct	31
1937	oct	14
1936	oct	27
1935	oct	7
1934	oct	28
1933	oct	26
1932	nov	11
1931	nov	6
1930	oct	19
1929	nov	5
1928	oct	30
1927	nov	5
1926	oct	25
1925	oct	10
1924	oct	23
1923	oct	23
1922	nov	10
1921	nov	3
1920	oct	30
1919	nov	5
1918	nov	2
1917	oct	20
1916	nov	14
1915	nov	15
1914	oct	26
1913	oct	21
1912	nov	1
1911	oct	28
1910	oct	28
1909	oct	12
1908	oct	2
1907	oct	21
1906	oct	10
1905	oct	30
1904	oct	28
1903	oct	24
1902	nov	27
1901	oct	18
1900	nov	8
1899	oct	1
1898	oct	27
1897	nov	12
1896	oct	19
1895	oct	10
1894	oct	15
1893	oct	29
1892	oct	6
1891	oct	23
1890	nov	1
1889	oct	7
1888	sep	30
1887	oct	12
1886	oct	2
1885	oct	9
1884	oct	24
1883	nov	3
1882	nov	13
1881	nov	15
1880	oct	18
1879	oct	25
1878	oct	28