---
updatedAt: 2026-06-17T10:50:10.000Z
agentTools:
  projectIndex: https://docs.tomorrow.io/llms.txt
---

# Air

The Tomorrow\.io REST Weather API `air` insight category will trigger for any of the events below.

## Air Stagnation (Advisory)

Issued for atmospheric conditions stable enough to cause air pollutants to accumulate in a given area, in cases where the following criteria are met and conditions to continue for at least 72 hours or are underway or are expected to start within 24 hours:\
**(1)** morning and afternoon mixing height of 1,500 ft AGL or less\
**(2)** morning and afternoon transport winds of 10 kts or less

## Dense Smoke (Advisory)

Issued when visibilities at or below 1/4 of a mile.

## Dust (Advisory)

Issued when there is a sudden drop in visibility to one mile or less, but greater than 1/4 mile, resulting in widespread or localized blowing dust.

## Blowing Dust (Advisory/Warning)

Issued when there is a long duration event of widespread or localized blowing dust reducing visibilities to one mile or less.\
1 mile for 3 hrs or more with sustained winds 25 mph

## Dust Storm (Advisory/Warning)

Issued when there is a sudden drop in visibility to 1/4 mile or less resulting in widespread or localized blowing dust.