It's that time of the year when the first killing frost/freeze hits central Pennsylvania. Typically, mid-October is when the first killing frost hits although light frosts can occur as early as mid-September.
Some areas of central Pennsylvania did have some frost in late September, but the duration of the frost and the extent of the frost did not kill most garden plants.
The cold air coming for Saturday morning will allow for a longer-duration frost and freeze and will also allow temperatures outside of the towns to dip will into the 20s, if not the teens.
The high pressure system bringing the cold weather originated in northern Canada and will park itself right over central Pennsylvania by Saturday morning. That will promote clear skies and calm winds which is the best setup for what meteorologist call "radiational cooling."
With the cold weather coming, you still have time to protect your plants. Covering them with buckets or blankets will prevent the frost from forming on the plants and may allow your plants to continue until the next threat of frost and freeze comes along.
Unsettled weather for the extended Labor Day weekend will be across the Southeast, Upper Midwest, northern Rockies and the Four Corners.
Tropical Depression 14-E is several hundred miles southwest of Mexico and is expected to strengthen slowly into a tropical storm.
A stormy weather pattern will prevail through September across much of southern South America.
While lulls in tropical activity in the Atlantic will continue, a rapid end to the hurricane season in September does not always occur during an El Niño.
The combination of moisture from Erika and a non-tropical system will drench areas from Florida to the South Carolina coast through the middle of the week.
Heat will be erased by an autumnlike air mass across parts of northern Europe.
Mecca, CA (1950)
126 degrees - highest ever for U.S. in Sept.
East Coast (1775)
Matecumbe Key, FL (1935)
Labor Day Hurricane hit Florida. Pressure at Matecumbe Key dipped to 26.35"/892.3 mb. Most intense hurricane ever to hit the U.S. with 200-mph wind. Tide of 15 feet; 408 dead.