Products for Clean Air and Energy Efficiency

Code Orange: UNHEALTHY for Sensitive Groups Air Quality Levels in California

Wednesday, December 3 – Thursday, December 4: In the West, an upper-level ridge of high pressure briefly building over the California will limit vertical mixing, trapping pollutants at ground-level. In addition, surface high pressure over the Great Basin will lead to generally light surface winds, limiting pollutant dispersion. As a result of these weather conditions, Air Quality levels are expected to be Code Yellow: MODERATE across much of California and portions of Utah, Nevada, Arizona, and New Mexico, with sites in Sacramento and San Diego, CA, expected to reach Code Orange: UNHEALTHY for Sensitive Groups Air Quality levels on Wednesday.

In the East, as a cold front approaches the Midwest, southwesterly winds ahead of the front will transport moisture and pollutants northward. These conditions will enhance particle production and lead to Code Yellow: MODERATE Air Quality levels for sites in the Midwest, Mid-Atlantic States, and New England.

View air quality for US Cities