Frost Dates: First and last frost dates for newman, 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 April 27. 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 20, so we don't dare plant that early. We wait a few days and by April 4 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° | Jan 8 | Dec 24 | -- | -- | -- | -- | -- | -- | -- |
| Last 24° | Feb 3 | Jan 21 | Jan 11 | Jan 1 | Dec 19 | -- | -- | -- | -- |
| Last 28° | Feb 28 | Feb 16 | Feb 7 | Jan 30 | Jan 23 | Jan 16 | Jan 7 | Dec 28 | Dec 8 |
| Last 32° | Apr 4 | Mar 24 | Mar 15 | Mar 8 | Mar 1 | Feb 22 | Feb 15 | Feb 6 | Jan 25 |
| Last 36° | Apr 27 | Apr 19 | Apr 14 | Apr 9 | Apr 4 | Mar 31 | Mar 26 | Mar 20 | Mar 12 |
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 11.
- There is a 50% chance of being hit by a 32° frost starting around November 24
- You have a 80% chance of seeing 32° by December 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° | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| First 20° | Dec 27 | Jan 12 | -- | -- | -- | -- | -- | -- | -- |
| First 24° | Dec 7 | Dec 15 | Dec 21 | Dec 28 | Jan 5 | -- | -- | -- | -- |
| First 28° | Nov 13 | Nov 22 | Nov 29 | Dec 4 | Dec 10 | Dec 15 | Dec 21 | Dec 29 | Jan 13 |
| First 32° | Nov 4 | Nov 11 | Nov 16 | Nov 20 | Nov 24 | Nov 28 | Dec 2 | Dec 7 | Dec 14 |
| First 36° | Oct 29 | Nov 3 | Nov 7 | Nov 10 | Nov 13 | Nov 16 | Nov 19 | Nov 23 | Nov 28 |
Data is provided by the NOAA National Centers for Environmental Information.