May 18, 2009
Conditions in CA have improved
California as a whole had improved air quality (PM 2.5 and Ozone) compared yesterday’s reported levels. As seen on AirNow’s hourly PM 2.5 AQI and Ozone, there were scattered areas of Code Orange, but most of the area was Code Yellow, showing an improvement over yesterday. Outside of California, PM 2.5 and Ozone were almost universally Green throughout the day.
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Fire activity was relatively sparse throughout the country, except for the North Dakota / Minnesota area as noted in yesterday’s post. An examination of the area reveals some wispy clouds intertwined with smoke, and a substantial number of areas with fire activity in the last 0 to 12 hours. Some elevated AOD could be seen, but much of the area has no reading:
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Central America continues to have a very large number of “hot spots” as seen on NOAA’s fire hazard mapping system, which may continue to affect air quality in the southern U.S.
