Clarion, Forest, Jefferson, Mercer and Venango counties under advisory.

By: KDKA-TV News Staff

PITTSBURGH (KDKA) — Gone are the days of 90 degree summer heat. Temperatures have been falling over the last few weeks, and now its time to start protecting your plants from frost.

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The National Weather Service has issued a Frost Advisory for several northern counties as temperatures are set to plunge into the mid-30s early Saturday morning.

The advisory will be in effect from 1 a.m. to 9 a.m. Saturday for Clarion, Forest, Jefferson, Mercer and Venango counties. It’s also for Garrett County in Maryland, and Eastern Tucker County in West Virginia.

The National Weather Service says it is possible the advisory could be expanded.

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Anyone with outdoor plants and flowers is advised to cover them up for the overnight hours.

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KDKA Meteorologist Ron Smiley says cooler air is set to arrive over the course of the day today. The cool front is now through, but temperatures this morning were closer to where they were 24 hours ago with morning lows forecast to drop down to 52 degrees. Thursday morning temperatures fell to 53 degrees.

The weather is expected to be quiet over the next week.

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