Herndon, VA 20164 Frost Dates
Frost dates for Herndon, VA, ZIP 20164
Typically, the last spring freeze lands around 04/13, roughly 228 days out. The first fall frost typically arrives around 10/26, about 195 frost-free days later.
Zone 7b (5 to 10°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 Herndon, not a forecast for this year.
What to do before the first frost
Zone 7b around Herndon has about 8 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
04/13 is the middle of 30 years of NOAA records, not a promise. Plant by 03/29 and you're betting against frost in roughly 9 years out of 10. 05/01 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Herndon compares
About 195 days separate Herndon's last and first frost, putting it 19,203 of 40,283 ZIP codes nationally. Within VA, it ranks 737 of 1,178.
Learn more
zone vs. frost date explains why Zone 7b and Herndon's frost date answer different questions, and the frost range explains how to read the range around Herndon's dates instead of trusting one.