Alturas, CA 96119 Frost Dates
Frost dates for Alturas, CA, ZIP 96119
The last spring frost here typically falls around 06/14, about 290 days from today. The first fall frost typically arrives around 09/18, about 94 frost-free days later.
Zone 6b (-5 to 0°F average annual minimum) comes from the USDA Plant Hardiness Zone Map; the frost dates above are the 1991-2020 normal at the nearest reporting NOAA station for Alturas, not a forecast for this year.
What to do before the first frost
Zone 6b around Alturas has about 3 weeks left before the first fall frost — that's the usual window to get a cold frame up if you want to keep harvesting past it.
How much risk comes with planting early here
06/14 is the middle of 30 years of NOAA records, not a promise. Plant by 05/26 and you're betting against frost in roughly 9 years out of 10. 07/03 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Alturas compares
At roughly 94 frost-free days, Alturas places 39,828 of 40,283 ZIP codes in this dataset. Within CA, it ranks 2,531 of 2,555.
Learn more
zone vs. frost date explains why Zone 6b and Alturas's frost date answer different questions, and the frost range explains how to read the range around Alturas's dates instead of trusting one.