Frost Dates: First and last frost dates for Manchester, KY
What's a safe temperature for tender plants? When the nightly temperature falls, frost can form, even above 32°, because the air is colder high above the ground and the frost can form up there and then fall down onto your garden and do some damage, even if it's 36° on the ground. So many factors come into play, including wind, concrete, houses, trees and other structures, etc etc etc. Because of all this, you might want to consider 36° as "the danger zone".
In your average springtime, you have a 90% chance that there will be no 36° nights by May 23. In other words, you can pretty much count on being safe from frost by that day. But we want to get those tomatoes in the ground as soon as possible, right? We see that there's still an 80% chance of 36° on April 24, so we don't dare plant that early. We wait a few days and by May 6 we are at the 50/50 point. At this point, we are close and we can start watching the weather forecast. If the upcoming week's forecast doesn't show below 40°, then it's probably okay to risk planting out your plants.
Temperature | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
---|---|---|---|---|---|---|---|---|---|
Last 16° | Mar 21 | Mar 14 | Mar 8 | Mar 4 | Feb 27 | Feb 23 | Feb 18 | Feb 12 | Feb 3 |
Last 20° | Apr 12 | Apr 3 | Mar 28 | Mar 22 | Mar 17 | Mar 12 | Mar 6 | Feb 28 | Feb 19 |
Last 24° | Apr 19 | Apr 13 | Apr 8 | Apr 4 | Apr 1 | Mar 28 | Mar 24 | Mar 20 | Mar 14 |
Last 28° | May 1 | Apr 26 | Apr 22 | Apr 19 | Apr 16 | Apr 12 | Apr 9 | Apr 5 | Mar 31 |
Last 32° | May 17 | May 11 | May 6 | May 3 | Apr 29 | Apr 26 | Apr 22 | Apr 18 | Apr 12 |
Last 36° | May 23 | May 17 | May 13 | May 9 | May 6 | May 2 | Apr 29 | Apr 24 | Apr 18 |
The charts on this page show the probabilities of receiving a certain temperature on a certain day. Some examples that might help:
- You have a small 20% chance of getting 32° by October 1.
- There is a 50% chance of being hit by a 32° frost starting around October 11
- You have a 80% chance of seeing 32° by October 21
- Said another way, you have a 1 in 5 chance at making it to that day without a 32° night.
Temperature | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
---|---|---|---|---|---|---|---|---|---|
First 16° | Nov 7 | Nov 15 | Nov 21 | Nov 26 | Dec 1 | Dec 6 | Dec 11 | Dec 17 | Dec 27 |
First 20° | Oct 26 | Nov 3 | Nov 9 | Nov 14 | Nov 18 | Nov 23 | Nov 28 | Dec 4 | Dec 12 |
First 24° | Oct 12 | Oct 20 | Oct 25 | Oct 30 | Nov 3 | Nov 8 | Nov 13 | Nov 18 | Nov 26 |
First 28° | Oct 5 | Oct 11 | Oct 16 | Oct 20 | Oct 24 | Oct 28 | Nov 1 | Nov 6 | Nov 13 |
First 32° | Sep 25 | Oct 1 | Oct 4 | Oct 8 | Oct 11 | Oct 14 | Oct 17 | Oct 21 | Oct 26 |
First 36° | Sep 15 | Sep 20 | Sep 24 | Sep 27 | Oct 1 | Oct 4 | Oct 7 | Oct 11 | Oct 16 |
Data is provided by the NOAA National Centers for Environmental Information.