August 3, 2009
AOD still high in the Northwest; Moderate conditions starting to spread out
Smoke from Alaska fires was still visible over great part of Northwest US / Northern and Central Plains (top, left) and certainly over Alaska as well (top, right). Fairbanks North Star Borough reported code orange today with a PM2.5 24 hour average of 67.4μg/m³ as of 4:00 PM. Yesterday's 24 hour average was 98.8μg/m³ (Unhealthy).
PM2.5 map today from AIRNow (bottom, left) shows moderate conditions spreading out in the Central Plains and Midwest. Yesterday it could be seen distinct pockets of yellow codes in the Southern US, California, Northwest and the region right below the Great Lakes. Today we see better conditions in California but lots of yellow codes popping up throughout the day in the Central/Eastern US. For tomorrow the forecast (bottom, right) is of code orange in a Northeastern area starting in Washington DC up to Worcester, MA and also in Southern California. Breaking up the forecast a little:
From Maryland Department of Environment (MDE) the forecast is that a high pressure system will bring warm and moist conditions across the Mid-Atlantic on Tuesday and clear skies will cause ozone pollution to likely increase into a Code Orange (Unhealthy for Sensitive Groups). PM's will increase in a warm-moist environment but will keep in the Moderate range.
And still in the AIRNow website the discussion over the Spokane, WA region is that a high pressure ridge that is currently over the region will begin to break down on Wednesday but until then hazy skies will remain, caused by the wildfires in the region.
Ozone levels are here.
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Below, the fire/smoke map from HMS at NOAA and the AOD map from MODIS Terra. Also, take a look in the Aqua AOD image here.
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