The Microclimate Problem: Why Your Backyard Isn't the Airport

Airports are chosen for weather stations because they offer open, flat, standardized sites. That's a feature for climatology, but it means airport data rarely matches any real neighborhood exactly.

A San Francisco resident in Mission Bay lives in a much warmer microclimate than SFO sitting in the fog belt. A resident of downtown Seattle gets more sun than SeaTac 13 miles south in a rainier zone.

The practical fix: treat city-level normals as a reasonable baseline and add local knowledge. If you moved here last year, ask neighbors about their gardens. Local gardeners are walking microclimate sensors.