Frost Dates: First and last frost dates for Glenbrook, NV

How to read these charts for the spring
As the growing season approaches, the days get longer, the weather begins to warm up, and the nights start being less cold. You're still getting frost, but the chance of nightly frosts gets less and less with each passing day. Eventually, the frost stops, and this is when your tender plants are fully safe. So, how do you plan for this? The probabilities on this page help you assess your risk of frost on any given day.

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 July 12. 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 7, so we don't dare plant that early. We wait a few days and by June 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.

In the Spring
Temperature 10% 20% 30% 40% 50% 60% 70% 80% 90%
Last 16° Apr 21 Apr 7 Mar 28 Mar 19 Mar 11 Mar 3 Feb 22 Feb 12 Jan 29
Last 20° May 14 May 3 Apr 25 Apr 18 Apr 12 Apr 6 Mar 30 Mar 22 Mar 12
Last 24° May 22 May 14 May 8 May 3 Apr 28 Apr 23 Apr 18 Apr 11 Apr 3
Last 28° Jun 8 Jun 1 May 27 May 23 May 19 May 15 May 11 May 6 Apr 29
Last 32° Jun 25 Jun 19 Jun 14 Jun 10 Jun 6 Jun 2 May 29 May 24 May 18
Last 36° Jul 12 Jul 5 Jun 30 Jun 25 Jun 21 Jun 17 Jun 13 Jun 7 May 31

How to read these charts for the fall
As your growing season comes to an end, the nightly temperatures for Glenbrook, NV start to go down, and therefore every day that goes by increases the chance that you'll get frost. Your risk of frost really begins around September 13, and by October 19 you're almost certain to have received at least one frost event.

The charts on this page show the probabilities of receiving a certain temperature on a certain day. Some examples that might help:

  1. You have a small 20% chance of getting 32° by September 21.
  2. There is a 50% chance of being hit by a 32° frost starting around October 5
  3. You have a 80% chance of seeing 32° by October 19
  4. Said another way, you have a 1 in 5 chance at making it to that day without a 32° night.
In the Fall
Temperature 10% 20% 30% 40% 50% 60% 70% 80% 90%
First 16° Nov 3 Nov 12 Nov 19 Nov 25 Nov 30 Dec 6 Dec 12 Dec 19 Dec 28
First 20° Oct 20 Oct 28 Nov 3 Nov 7 Nov 12 Nov 16 Nov 21 Nov 27 Dec 5
First 24° Oct 8 Oct 16 Oct 22 Oct 27 Oct 31 Nov 5 Nov 10 Nov 16 Nov 24
First 28° Sep 24 Oct 2 Oct 7 Oct 12 Oct 17 Oct 21 Oct 26 Nov 1 Nov 8
First 32° Sep 13 Sep 21 Sep 26 Oct 1 Oct 5 Oct 9 Oct 14 Oct 19 Oct 27
First 36° Aug 21 Aug 30 Sep 5 Sep 10 Sep 14 Sep 19 Sep 24 Sep 30 Oct 8

Data is provided by the NOAA National Centers for Environmental Information.