National Weather Service United States Department of Commerce

Strong Atmospheric River Bringing Heavy Rain to the Pacific Northwest; Areas of Snow in the North-Central and Eastern U.S.

A strong atmospheric river will bring prolonged heavy rainfall along with gusty winds to the Pacific Northwest through much of this week. The heavy rainfall may lead to widespread urban and river flooding. Accumulating snow is expected over parts of the central Appalachians and Mid-Atlantic today as well as the Upper Midwest and the Upper Great Lakes this evening into Tuesday. Read More >

Smoke dispersal is categorized by using the Ventilation Rate. Ventilation Rate forecasts for a specific point can be found using the Fire Weather Dashboard. Click a spot on the map and scroll down to find daily and hourly Ventilation Rate values for the next few days.

 

Fire Weather Dashboard

 

The link above is configured to display smoke dispersal categories as shown here:

 

  Smoke Dispersal Vent. Rate, knot-feet (x1000)
     Excellent             150 or greater
     Very Good 100 to 149.99
     Good 60 to 99.99
     Fair 40 to 59.99
     Poor less than 40

 

Ventilation Rate = Transport Wind (kts) Mixing Height (ft)