Frost Dates: First and last frost dates for flint fcwos, mi
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 September 1.
- There is a 50% chance of being hit by a 32° frost starting around September 12
- You have a 80% chance of seeing 32° by September 24
- 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° | Oct 31 | Nov 5 | Nov 9 | Nov 12 | Nov 15 | Nov 18 | Nov 21 | Nov 25 | Nov 30 |
First 20° | Oct 17 | Oct 23 | Oct 27 | Oct 30 | Nov 3 | Nov 6 | Nov 10 | Nov 14 | Nov 19 |
First 24° | Sep 26 | Oct 3 | Oct 8 | Oct 13 | Oct 17 | Oct 21 | Oct 25 | Oct 30 | Nov 6 |
First 28° | Sep 14 | Sep 20 | Sep 24 | Sep 27 | Sep 30 | Oct 3 | Oct 7 | Oct 11 | Oct 16 |
First 32° | Aug 26 | Sep 1 | Sep 5 | Sep 9 | Sep 12 | Sep 16 | Sep 19 | Sep 24 | Sep 30 |
First 36° | Aug 11 | Aug 18 | Aug 24 | Aug 29 | Sep 2 | Sep 7 | Sep 11 | Sep 17 | Sep 25 |
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 July 18. 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 June 2, so we don't dare plant that early. We wait a few days and by June 21 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° | Apr 20 | Apr 16 | Apr 12 | Apr 9 | Apr 7 | Apr 4 | Apr 1 | Mar 29 | Mar 24 |
Last 20° | May 3 | Apr 28 | Apr 24 | Apr 21 | Apr 18 | Apr 16 | Apr 13 | Apr 9 | Apr 4 |
Last 24° | May 16 | May 11 | May 7 | May 4 | May 1 | Apr 29 | Apr 26 | Apr 22 | Apr 17 |
Last 28° | Jun 2 | May 27 | May 23 | May 19 | May 15 | May 12 | May 8 | May 3 | Apr 27 |
Last 32° | Jun 19 | Jun 13 | Jun 9 | Jun 5 | Jun 2 | May 30 | May 26 | May 22 | May 17 |
Last 36° | Jul 18 | Jul 9 | Jul 2 | Jun 26 | Jun 21 | Jun 15 | Jun 9 | Jun 2 | May 24 |
Data is provided by the NOAA National Centers for Environmental Information.