National Weather Service United States Department of Commerce

Widespread Showers in the Eastern US; Severe Thunderstorms in the Plains; Heatwave in the Desert Southwest

Widespread showers and thunderstorms across much of the central and eastern U.S. will produce areas of excessive rainfall, especially in the southern Mid-Atlantic states. Scattered severe thunderstorms are expected from Montana into portions of the central/southern Plains this weekend. A heatwave will build in the Desert Southwest, in parts of Arizona, southeastern California, and southern Nevada. Read More >

Area Air Quality Index


Note that the Air Quality Index (AQI) here is not an official forecast, except for the EPA AirNow Widget to the right. The AQI below (not EPA AirNow) is based on the most recent observation via MesoWest for the specified time, and not a time-average, so the AQI values will be more variable than other official sites such as AirNow. Many sites only report some of the pollutants used in this calculation (O₃, PM₂.₅, PM₁₀, NO₂, SO₂, CO), and the AQI equations used are based on those from AirNow. The nearby Air Quality Index table is based on the AQI values near the longitude/latitude for the station indicated. On the map, hover/click the site to see the values for the individual pollutants. To manually enter a station ID not listed, change the URL to include "&id=____&", where ____ is the desired station ID. To manually enter a lat/lon pair, include "&lt=___&ln=___&" in the URL, where the ___ are the lat/lon values.