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