Loyalton Fire Pyrocumulonimbus Time Lapse (Fire Tornado Warning) 8/15/2020

Hot, dry conditions and anomalously low fuel moisture, in combination with an unstable low-to-mid-level atmosphere, allowed the Loyalton wildfire to spread rapidly with no containment on the morning of 8/15. Robust heat and moisture fluxes from the wildfire caused the rising smoke plume to rise above condensation levels and develop two pyrocumulonimbus thunderstorms (aka cumulonimbus flammagenitus or pyrocumulus). Wind shear and mountainous terrain helped induce rotation in the smoke column.

At 2:35 PM PST, the NWS issued its first ever fire tornado warning. The fire storm produced three tornadoes, two of which were anticyclonic EF1s that snapped and uprooted quaking aspen and jeffrey pine trees. The image in the video shows the third EFU tornado.

The lightning-sparked fire burned about 47,029 acres in the Tahoe National Forest and Humboldt-Toiyabe National Forest and destroyed 35 structures before being fully contained on September 14, 2020.

How firestorms work:    • How Firestorms Form  
Sources:
https://inciweb.nwcg.gov/incident/6975/
https://www.forbes.com/sites/marshall...
https://www.nytimes.com/2020/08/16/us...
https://www.usatoday.com/story/news/w...
http://archive.is/deKIa
  / 1294753883072454657  
https://data.redding.com/tornado-arch...

Time Lapses from the ALERTWildfire network http://www.alertwildfire.org managed by the Nevada Seismological Laboratory at the University of Nevada, Reno in partnership with PG&E.