Ag Weather Update

Matt Dixon, Meteorologist

UK Ag Weather Center

Updated October 19, 2021

Past Conditions

It’s been an unusually warm and wet October, according to data through October 18. The state has averaged just over 2.5 inches and ran 10 degrees above normal. October has felt more like an extension of summer than fall. However, a strong cold front passed through the area on Friday, flipping the switch to fall. Ahead of the boundary, Kentucky was running very mild and borderline humid with highs in the low to middle 80s on Thursday, about 10-15 degrees above normal for this time of year. Behind the boundary, we saw highs swing about 20 degrees, dipping back into the upper 50s to mid-60s on Saturday and Sunday, below normal for mid-October. The coolest temperatures arrived on Sunday morning with many folks waking up to temperatures in the middle 30s to low 40s, bringing patchy frost into the picture for the first time this fall. Below is a look at those lows from across the state, courtesy of the Kentucky Mesonet.

In addition to the temperature swing, the state saw multiple rounds of rainfall. The first round arrived on Monday night, mainly impacting the western half of the state before dissipating across the eastern half. This was followed by light round on Wednesday, ahead of more significant showers and storms moving into the area on Friday with the passage of the cold front. While I have not seen any damage reports, storms across Western KY were capable of producing damaging winds, something we do not want to see with corn harvest lagging behind this year. Overall, most of Kentucky saw rain accumulations stay under an inch for the week.

Data for the Past 7 Days

Forecast

Weather-wise, it’s been a fantastic start to the workweek, with fall-like cool weather. Temperatures will run on a rollercoaster the next several days, running slightly above normal today (70s), taking a step back for Thursday/Friday, and then increasing again over the weekend. There is no threat of frost or freezing temperatures, with lows generally staying in the 40s and 50s. Our next chance of rain arrives tomorrow with the passage of a cold front. As of now, it looks as though rain will remain scattered in coverage and most will likely stay under a quarter inch with the boundary’s passage, highest across Southeastern KY. Most of Western KY is even looking dry. Below is a look at those forecast accumulations from the Weather Prediction Center. Looking further out, after some light isolated activity across the Bluegrass on Friday, our next shot of showers arrives over the second half of the weekend and into early next week.

Take advantage of the drier conditions this week as outlooks favor above normal temperatures and precipitation for the last week of October and start of November. Just as a reminder, dark red shades show high confidence from the forecasters in above normal temperatures. Dark green indicates high confidence in above normal rainfall.

Read the Kentucky Ag Weather Synopsis

Average first freeze of fall

The end of the growing season is approaching. The release of the new climate normals earlier this spring means we also have a new set of frost/freeze normals. In doing so, I looked at the average first freeze date for various locations across the Commonwealth based on the 1991 to 2020 climate normals. As you can see in the table below, several locations now see their average first freeze occur sometime in late October or early November. We’re getting close!

Following the shift to a warmer climate across Kentucky over the past decade, the average first freeze dates above have been pushed back in the fall season. In the chart below, I compared the average first freeze date for various locations across the state according to three different sets of normals: 1971-2000, 1981-2010, and 1991 to 2020. As you can see, some stations have seen their average first freeze date pushed back a week or more over the past 20 years.