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