A distinct haze has been hanging around the D.C. area today, which may actually be smoke from over 2,000 miles away.
What a beautiful morning it has been, with lows in the 50s and 60s across the region, including a record-tying low of 59 degrees at BWI Marshall. With such low humidity levels across the region though, you would expect to see deep blue colored skies with now a few white puffy cumulus clouds. Instead, a haze has settled in over the region.
- Visible satellite image after 11am
Take a look at the visible satellite image above. Just by looking at this image by itself without motion, it is very hard to see anything that may signify smoke over the D.C. area. But click here to see the satellite in motion. Did you happen to see the very light colored area over D.C. right after sunrise? This is showing the possibility of either some extremely thin clouds, or more than likely, a very thin layer of smoke in the atmosphere.
- Courtesy: NASA MODIS
A number of fires have not only been burning in the Pacific Northwest, but also well north of the border in the Northwest Territories of Canada. Above is a look at the NASA MODIS satellite world view which I stumbled upon while perusing the web. I circled the regions of smoke that were showing up yesterday in Northern Canada and over the Hudson Bay. Given the flow of the atmosphere, much of the smoke more than likely was pushed south and eventually southeast into the Midwestern U.S., Northeast and Mid Atlantic States.
- Water Vapor Imagery Tuesday Morning the 29th
The upper-level flow shows a large trough through the eastern part of the U.S. and a large ridge over the western U.S. The resulting steering flow has been from Northern Canada southeast through the Midwestern States and directly into the D.C. area. Check out the water vapor loop here. Keep in mind the orange, black and dark grey show very dry air while the purple, blue and white areas show increased levels of atmospheric moisture.
The effects from smoke in the D.C. area will be minimal and air quality is still expected to be good through the next few days, though the haze may hang around tomorrow and Thursday.
- NASA MODIS image from July 23rd
The fires have burned over two million acres of land in the Northwest Territories and are thought to have been caused by lightning.