The first and last frost date percentages on the chart for my location (Port Townsend, WA) do not make sense to me. Looking at 32 degrees, 10% of the time it (last frost) is on Mar 28 and 90% of the time it is on Jan 24th. It is general knowledge that our last frost date is usually about the third week in March, so this percentage chart looks backwards to me. Please elucidate!

Thank you!!

Lys Burden, Growing Groceries Instructor

@LysBurd
What it is telling you is that on Jan 24 you have a 90% chance of frost while on Mar 28 you have only a 10% chance of frost. I hope this helps.

Thank you, Bruce! Most helpful! The chart did not make clear to me that it was listing "chance of frost" in those percentages... maybe some relabeling might help clarify?

Cheers! Lys