Breathing Index 🫁

Dry-spore conditions

weather proxy · 0–5 · each hour, in season

Cladosporium spores under a microscope
Cladosporium, the dry-weather spore the forecast stands in for. Photo: Medmyco, CC BY-SA 4.0.
What it is

A guess at dry-air spores from the weather alone: warm, dry, windy, no rain in two days, after a wet spell. Each condition met adds a point, out of five.

How it affects breathing
  • Evidence. The same spores as mold, by a stand-in: a mechanism, thin data. It can raise a suspicion and never confirm one.
  • How likely. The same as Mold, for people sensitized to mold.
  • What helps. The same as Mold.
How Breathing Index measures it

Your Breathing Index counts the five conditions against each hour’s forecast, in season only, and always marks the result as an estimate, since no instrument looked at the air.

Where the number comes from

No instrument looked at the air. Five weather conditions off the forecast, counted.

Breathing Index is a breathing lens on public air data — not medical advice. Trust your symptoms and your asthma action plan over anything on this screen.

Breathing Index is a free logbook for this. You rate your breathing from 1 to 4, it stores every one of these readings alongside the rating, and over time it marks which of them your own days say affect you. What this is · Open it