Post-Eaton Fire exposure — the 2025 defining pattern.
Glendale sits directly west of the Pasadena-Altadena burn corridor. Prevailing winds pushed heavy smoke and ash westward for weeks, and multi-week active fire meant extended smoke penetration. HVAC distributed contamination throughout homes and buildings city-wide. Northern Glendale (Montrose, La Crescenta-adjacent) sustained heavier deposition than southern neighborhoods. Wildfire smoke composite chemistry is more aggressive than wildland-only.