Zip code 32011, Callahan FL is in USDA Hardiness Zone 8b: 15F to 20F. Using updated climate data through 2010, 32011 is in the Plantmaps Hardiness Zone 8b: 15F to 20F. The average first frost in 32011 is between December 1 - 10, while the average last frost occurs between February 21 - 28. 32011 is part of Ecoregion 75f - Sea Island Flatwoods. 32011 averages 121 - 150 days per year where the temperatue exceeds 86°F.