Frost Dates: First and last frost dates for South Lake Tahoe Ap, 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 13, so we don't dare plant that early. We wait a few days and by July 22 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 6 | Apr 27 | Apr 20 | Apr 14 | Apr 9 | Apr 4 | Mar 29 | Mar 22 | Mar 13 |
Last 20° | May 11 | May 5 | Apr 30 | Apr 27 | Apr 23 | Apr 20 | Apr 16 | Apr 12 | Apr 6 |
Last 24° | Jun 11 | Jun 3 | May 28 | May 22 | May 17 | May 12 | May 7 | May 1 | Apr 22 |
Last 28° | Jul 5 | Jun 28 | Jun 23 | Jun 19 | Jun 15 | Jun 11 | Jun 7 | Jun 2 | May 27 |
Last 32° | Jul 30 | Jul 24 | Jul 20 | Jul 17 | Jul 13 | Jul 10 | Jul 6 | Jul 2 | Jun 27 |
Last 36° | Aug 4 | Jul 31 | Jul 27 | Jul 25 | Jul 22 | Jul 19 | Jul 17 | Jul 13 | Jul 9 |
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 2
- 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 25 | Oct 29 | Nov 1 | Nov 4 | Nov 6 | Nov 8 | Nov 11 | Nov 13 | Nov 17 |
First 20° | Oct 4 | Oct 10 | Oct 14 | Oct 18 | Oct 21 | Oct 25 | Oct 28 | Nov 2 | Nov 7 |
First 24° | Sep 13 | Sep 20 | Sep 24 | Sep 29 | Oct 3 | Oct 6 | Oct 11 | Oct 16 | Oct 22 |
First 28° | Aug 18 | Aug 27 | Sep 2 | Sep 7 | Sep 12 | Sep 17 | Sep 22 | Sep 28 | Oct 7 |
First 32° | Aug 1 | Aug 8 | Aug 13 | Aug 17 | Aug 20 | Aug 24 | Aug 28 | Sep 2 | Sep 9 |
First 36° | Jul 29 | Aug 1 | Aug 4 | Aug 6 | Aug 9 | Aug 11 | Aug 13 | Aug 16 | Aug 20 |
Data is provided by the NOAA National Centers for Environmental Information.