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