Dayton, OH 45405 Frost Dates
Frost dates for Dayton, OH, ZIP 45405
The last spring frost here typically falls around 04/16, about 231 days from today. The first fall frost typically arrives around 10/28, about 194 frost-free days later.
Dayton sits in USDA Zone 6b (-5 to 0°F average annual minimum). The dates above are NOAA's 1991-2020 normal at the nearest reporting station, a 30-year average, not a forecast.
What to do before the first frost
Zone 6b around Dayton has about 9 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.
Why 04/16 isn't a guarantee
04/16 is the middle of 30 years of NOAA records, not a promise. Plant by 04/02 and you're betting against frost in roughly 9 years out of 10. 05/03 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Dayton compares
At roughly 194 frost-free days, Dayton places 19,407 of 40,283 ZIP codes in this dataset. Within OH, it ranks 146 of 1,383.
Learn more
the frost range explains how to read the range around Dayton's dates instead of trusting one, and local microclimates explains what one yard in Dayton can differ from the 45405 normal.