National Weather Service United States Department of Commerce

Heat the Southwest; Fire Weather in the Central U.S.; Kona Low Impacting Hawaii

A rare March heat wave is ongoing with much above-normal temperatures over the Southwest U.S. through this weekend. Periods of critical fire weather will persist from the central Rockies to the central and southern Plains through the weekend as gusty winds and low relative humidity continue. A Kona low will continue to bring several rounds of moderate to heavy rainfall to Hawaii through Sunday. 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)