Frost Dates: First and last frost dates for Mondovi, WI
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 22.
- There is a 50% chance of being hit by a 32° frost starting around September 28
- You have a 80% chance of seeing 32° by October 5
- 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 22 | Oct 28 | Nov 1 | Nov 4 | Nov 7 | Nov 10 | Nov 14 | Nov 18 | Nov 23 |
First 20° | Oct 11 | Oct 16 | Oct 20 | Oct 23 | Oct 27 | Oct 30 | Nov 2 | Nov 6 | Nov 12 |
First 24° | Oct 5 | Oct 10 | Oct 13 | Oct 17 | Oct 20 | Oct 23 | Oct 26 | Oct 29 | Nov 4 |
First 28° | Sep 24 | Sep 28 | Oct 1 | Oct 4 | Oct 6 | Oct 9 | Oct 11 | Oct 14 | Oct 19 |
First 32° | Sep 18 | Sep 22 | Sep 24 | Sep 26 | Sep 28 | Sep 30 | Oct 3 | Oct 5 | Oct 9 |
First 36° | Sep 7 | Sep 10 | Sep 13 | Sep 15 | Sep 17 | Sep 19 | Sep 21 | Sep 23 | Sep 27 |
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 11. 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 16, 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 13 | Apr 9 | Apr 6 | Apr 3 | Mar 31 | Mar 28 | Mar 26 | Mar 22 | Mar 18 |
Last 20° | Apr 17 | Apr 14 | Apr 11 | Apr 9 | Apr 7 | Apr 5 | Apr 3 | Mar 31 | Mar 28 |
Last 24° | Apr 30 | Apr 25 | Apr 21 | Apr 18 | Apr 16 | Apr 13 | Apr 10 | Apr 6 | Apr 1 |
Last 28° | May 14 | May 9 | May 5 | May 2 | Apr 29 | Apr 26 | Apr 23 | Apr 19 | Apr 14 |
Last 32° | May 31 | May 26 | May 22 | May 18 | May 15 | May 12 | May 9 | May 4 | Apr 29 |
Last 36° | Jun 11 | Jun 5 | Jun 2 | May 29 | May 26 | May 23 | May 20 | May 16 | May 11 |
Data is provided by the NOAA National Centers for Environmental Information.