Q.Frost Dates & Planting Timing
How much does frost date vary within a county?
A.
Local frost dates can vary by 2-4 weeks within a single county, driven by elevation, slope aspect, cold air drainage, and proximity to water. Valley bottoms frost earlier in fall and later in spring than nearby hilltops. Urban areas frost weeks later than nearby rural sites.
Read your county's frost-date table as a regional anchor, then adjust for your specific microclimate. The page includes a microclimate explanation.