Data Sources & Methodology

Pollen data

Pollen data comes from the Pollen API, a Google Maps Platform Environment API.

Source: Includes pollen data from Google — Google Maps

AirMorrow-derived summaries: Includes data from Google Maps.

Overall Pollen Level

The site summary uses the highest available Tree, Grass, or Weed Universal Pollen Index (UPI) for the displayed day. If multiple pollen types share the highest UPI, all tied types are treated as the summary basis. The summary describes environmental pollen conditions and does not estimate an individual's symptoms.

Refresh cadence

Pollen data is refreshed once each UTC day. Future forecast values are not displayed after 24 hours without a successful refresh.