May 19, 2009
A Beautiful Day with Good Air Quality
Air quality was Code Green (Good) across most of the country today, with only a few scattered locations of Code Yellow (Moderate) PM2.5 and ozone, as shown by the loops of AQI values (below).
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A strong high pressure system extending across the central and eastern portions of the U.S. was responsible for the good air quality conditions. Today’s MODIS Aqua true color image overlaid with the 18 UTC synoptic analysis (below in Google Earth) shows the remarkably cloud-free skies enjoyed by much of the Midwest and Eastern parts of the nation.
It was also a quiet day for fire activity, as shown by today’s Hazard Mapping System (HMS) Fire and Smoke Product (below). There are some hotspots analyzed in Texas, and many fires are still burning in Central America, but no significant areas of smoke are reported. Tomorrow may be a different story, however, as the National Weather Service has posted Red Flag Warnings for the Upper Peninsula and northern portion of the Lower Peninsula of Michigan, west central Colorado, and southeastern Alaska. A Red Flag Warning means that critical fire weather conditions are expected to occur tomorrow. The combination of high temperatures, low humidity, and gusty winds will create the potential for explosive fire growth.
