Blue Grass Airport bottomed out at 39 degrees Monday under mostly cloudy skies as the frost advisory ended at 9 a.m. Sunday's low was 36. No freeze at the airport.

Updated Oct. 19: The frost advisory ended at 9 a.m. Monday. Blue Grass Airport’s hourly readings bottomed out at 39 degrees, under mostly cloudy skies.

Updated Oct. 18: The National Weather Service upgraded the watch to a freeze warning early Saturday. Blue Grass Airport’s hourly readings bottomed out at 36 degrees Sunday morning. A frost advisory now covers Fayette County from 1 a.m. to 9 a.m. Monday.

Monday: how the frost advisory ended

The frost advisory for Fayette County ran from 1 a.m. to 9 a.m. Monday. Clouds moved in overnight, and the hourly observations from Blue Grass Airport read “mostly cloudy” for most of the night.

The airport’s hourly readings bottomed out at 39 degrees, at 6:54 a.m. and again at 7:54 a.m. By 9:54 a.m. the reading was 52 degrees. Neither cold night this weekend brought a freeze at Lexington’s official station.

The frost advisory, as issued Sunday

The National Weather Service in Louisville issued a frost advisory at 1:39 p.m. Sunday. It covers Fayette County and much of central Kentucky and south central Indiana from 1 a.m. to 9 a.m. Monday.

The weather service said temperatures as low as 34 “will result in frost formation.” It said sensitive outdoor plants “may be killed if left uncovered.”

The point forecast for Lexington, as of Sunday afternoon, calls for:

  • Sunday night: clear, with a low around 37 and patchy frost after 5 a.m.
  • Monday: patchy frost before 9 a.m., then sunny with a high near 67
  • Monday night: clear, with a low around 39

How cold it got Sunday

The weather service upgraded Friday’s freeze watch to a freeze warning at 12:57 a.m. Saturday. The warning called for temperatures as low as 30 in Fayette, Scott, Bourbon, Clark, Harrison and Nicholas counties from 1 a.m. to 9 a.m. Sunday.

Lexington’s official station stayed above freezing. Hourly observations from Blue Grass Airport bottomed out at 36 degrees, at 1:54 a.m. and again at 3:54 a.m. Sunday. Colder, low-lying spots outside the city can run several degrees below the airport reading.

What we reported Friday

Lexington could see freezing temperatures early Sunday. The National Weather Service in Louisville issued a freeze watch Friday afternoon for Fayette County and five other Central Kentucky counties.

The watch runs from 1 a.m. to 9 a.m. Sunday. Temperatures could fall as low as 32 degrees, according to the weather service alert.

Where and when

The watch covers six counties:

  • Fayette
  • Scott
  • Bourbon
  • Clark
  • Harrison
  • Nicholas

The weather service said frost and freeze conditions “could kill crops, other sensitive vegetation and possibly damage unprotected outdoor plumbing.” Its instruction: “Take steps now to protect tender plants from the cold.”

A watch means a freeze is possible. If forecasters grow more confident, they can upgrade it to a freeze warning.

The forecast

The point forecast for Lexington, updated Friday afternoon, calls for:

  • Friday night: a 50% chance of showers before 4 a.m. and a low around 41
  • Saturday: mostly sunny with a high near 55 and a north wind of 9 to 17 mph
  • Saturday night: clear, with a low around 34 and areas of frost after 5 a.m.
  • Sunday: areas of frost before 9 a.m., then sunny with a high near 62
  • Monday: areas of frost again for an hour after 7 a.m., then a high near 65

The forecast low of 34 is for a point in central Lexington. The watch, which covers the whole county, allows for temperatures as low as 32.

What it means for you

  • Bring in potted plants and hanging baskets Sunday evening, or cover tender plants with a sheet or bucket. Take the cover off once the sun is up Monday.
  • Pick ripe tomatoes, peppers and other warm-weather crops before dark Sunday if you want to save them.
  • Disconnect garden hoses and shut off or cover outdoor faucets. The weather service named unprotected outdoor plumbing as a risk.
  • Bring pets inside for the night.
  • Allow extra time Monday morning to clear frost from windshields.

The frost advisory has ended. Plan the week with our things to do guide, and keep our power outages page handy as the colder months begin.