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09/30/2017

Chilly Mornings Ahead, Average First Frost

Do you feel that?! A chill in the air? That's all thanks to a series of cold fronts that swept through the area this week; one on Wednesday and another on Friday. The second front was a moisture deprived cold front though, so we did not see any rain from the boundary. 
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The two fronts dropped our temperatures significantly. On Wednesday, we were tying a record high temp in the low 90s.

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Three days later, today's high will be only in the low to mid 70s!  
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While the high temps will be a lot cooler, the low temps have probably been a SHOCK to your system! Today and tonight will be the coolest highs and lows this week. The majority of Kentuckiana will fall into the 40s tonight. Downtown will be slightly warmer- in the low 50s. Check out the temp change of our lows the last few days. 

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To put this in perspective though, average nighttime lows for the last day of September are in the mid 50s. So we are below average, but only by a degree or two. Today and tomorrow are days to dress in layers! It will be chilly to start and then temps will eventually be in the low 70s, once again, by the afternoon with plenty of sunshine.  We will actually begin to warm by Sunday afternoon and into next week. 

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So will it be cold enough for a FROST?? 

We will be flirting with upper 30s, but no one in the viewing area will be cold enough to see frost, which is at least 36 degrees. But that made me think about when we typically DO see a first frost/freeze. The average date of the first 36 degree reading (Frost) in Louisville is October 20th, so only three weeks away! 

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It's important to note that these statistics are for the city of Louisville.  Rural areas may have significantly different statistics, even within Jefferson County.  

10-8 36

Image Courtesy: NWS

The average date of the first 32 degree reading (Freeze) in Louisville is November 1st...

10-8 32

Image Courtesy: NWS

The average date of the first 28 degree reading (Hard Freeze) in Louisville is November 12th...

10-8 28

Image Courtesy: NWS

And for the curious bunch, here are a lot of other records and stats: 

Records:
Latest spring frost (36°): May 27, 1961
Latest spring freeze (32°): May 10, 1966
Latest spring hard freeze (28°): April 23, 1986
Earliest final spring frost (36°): March 15, 1884
Earliest final spring freeze (32°): March 5, 1927
Earliest final spring hard freeze (28°): February 19, 1905
Earliest fall frost (36°): September 25, 1950
Earliest fall freeze (32°): October 3, 1974
Earliest fall hard freeze (28°): October 10, 1964
Latest first fall frost (36°): November 23, 1902
Latest first fall freeze (32°): November 28, 1899 and November 28, 2009
Latest first fall hard freeze (28°): December 13, 1939
Longest growing season: 257 days in 1884
Shortest growing season: 166 days in 1976

Averages, using the entire period of record:
Last spring frost (36°): April 18
Last spring freeze (32°): April 5
Last spring hard freeze (28°): March 24
First fall frost (36°): October 20
First fall freeze (32°): November 1
First fall hard freeze (28°): November 12

Normals, 1981-2010:
Last spring frost (36°): April 14
Last spring freeze (32°): April 3
Last spring hard freeze (28°): March 23
First fall frost (36°): October 25
First fall freeze (32°): November 4
First fall hard freeze (28°): November 16

Are you loving the fall weather? Or do you wish we were still in the 90s? Let me know on my social media pages! The links are below. 

Katie McGraw's Facebook Page

Katie McGraw's Twitter Page

-Katie McGraw 

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