Frost Dates: First and last frost dates for Martin U Of T Branch E, TN
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 April 29. 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 8, so we don't dare plant that early. We wait a few days and by April 16 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 6 | Feb 27 | Feb 21 | Feb 17 | Feb 13 | Feb 8 | Feb 4 | Jan 29 | Jan 20 |
Last 20° | Mar 22 | Mar 15 | Mar 10 | Mar 5 | Mar 1 | Feb 25 | Feb 21 | Feb 16 | Feb 8 |
Last 24° | Apr 5 | Mar 29 | Mar 25 | Mar 21 | Mar 17 | Mar 13 | Mar 9 | Mar 4 | Feb 26 |
Last 28° | Apr 13 | Apr 7 | Apr 3 | Mar 31 | Mar 27 | Mar 24 | Mar 20 | Mar 16 | Mar 11 |
Last 32° | Apr 20 | Apr 16 | Apr 13 | Apr 10 | Apr 8 | Apr 6 | Apr 3 | Mar 31 | Mar 27 |
Last 36° | Apr 29 | Apr 25 | Apr 22 | Apr 19 | Apr 16 | Apr 14 | Apr 11 | Apr 8 | Apr 4 |
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 13.
- There is a 50% chance of being hit by a 32° frost starting around October 23
- You have a 80% chance of seeing 32° by November 1
- 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 18 | Nov 27 | Dec 3 | Dec 8 | Dec 12 | Dec 17 | Dec 23 | Dec 29 | Jan 8 |
First 20° | Nov 9 | Nov 17 | Nov 23 | Nov 27 | Dec 2 | Dec 6 | Dec 11 | Dec 16 | Dec 24 |
First 24° | Nov 1 | Nov 7 | Nov 12 | Nov 15 | Nov 19 | Nov 22 | Nov 26 | Nov 30 | Dec 6 |
First 28° | Oct 21 | Oct 27 | Oct 31 | Nov 4 | Nov 7 | Nov 10 | Nov 14 | Nov 18 | Nov 23 |
First 32° | Oct 8 | Oct 13 | Oct 17 | Oct 20 | Oct 23 | Oct 25 | Oct 28 | Nov 1 | Nov 6 |
First 36° | Sep 29 | Oct 3 | Oct 6 | Oct 8 | Oct 11 | Oct 13 | Oct 16 | Oct 19 | Oct 23 |
Data is provided by the NOAA National Centers for Environmental Information.