Two types of AQI data are being made available: observational GRIB data
and forecast text data. The AQI GRIB data depicts the current day's
hourly-observed air quality measurements. These observations are
derived from reporting stations in over 40 participating states including the
West and Southwest as well as most states East of the Mississippi River.
The text forecasts are city-specific and cover more than 160 metropolitan
areas. Represented is the maximum AQI category (i.e, pollutant level) for
the current and next day periods.

The text forecast product is found on WSI's systems under product header
AEUS99 KWSI. The GRIB data can be accessed and utilized in manners
similar to NCEP model data (Numeric Grid Query -> Other GRIB data) on
WxPro 3.0 systems.

Please note that availability of these products is dependent upon the
EPA's timely collection, dissemination and availability of the data from
participating states. Hourly data is typically available daily from 12Z
through 05Z. Please note, however, that due to the diurnal nature of
ozone (i.e., AQI), data may be "missing" from some western states in the
early hours (~12-16Z) and "missing" from some eastern states in the later
hours (~01-05Z). The current hour's observations will typically be
available on user's systems approximately 55 minutes past the top of the
hour.

Additional information regarding these products can be obtained by
visiting www.epa.gov/airnow.

Questions regarding implementation on WSI systems can be directed to
WSI Customer Support at customersupport@wsicorp.com or
(978) 670-5150, press #1.