It wasn’t snow that coated a few cars in West Virginia and Maryland earlier Friday. Satellite trends show it was dust!
The same weather system that brought the dust to Western Maryland triggered record heat and pollen counts.
The cold front that just moved through Washington earlier Friday had roots in the Southern Plains on Wednesday. The soil has been stripped of moisture in the Southern Plains, thanks to recent drought, so it has become rather dusty.
A strong, southwest wind at 60 to 70 mph ahead of the front picked up dust particles in the Southern Plains on Wednesday. This dust was carried northeast ahead of the front and eventually ended up in the Ohio Valley and West Virginia on Thursday.
The same concept applies to western wildfire smoke in the fall season. Oftentimes, if the smoke plume over a large western wildfire gets caught up in the jet stream, the sky appears milky in color for a few days in the D.C. area, despite high pressure and low humidity in place.
In this case, the mid-Atlantic and Western Maryland just happened to be right in the path of the incoming dust ahead of the front and it settled on cars when the winds lightened up a bit late Thursday and early Friday morning.
Smoke, on the other hand, remains suspended in the air, but if it’s dense enough, it can give off an odor.
The southwest wind that transported the dust into the mountains west of Washington helped push the mercury to record levels in D.C. on Thursday.
Not only did record high temperatures fall in the region, but the daily count for tree pollen in this morning’s report reached a record high for February of 2,724.6 grains per cubic meter in the D.C. region.
The pollen count record from the United States Army Centralized Allergen Extract Laboratory dates back to 1998.
