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