Influence of a sea-breeze front over a fire plume, Pedrogão Grande wildfires (20 June 2017)

Abstract

During the afternoon of 20 June 2017, two massive wildfires were ongoing more than 30 km to the east-southeast of the city of Coimbra, central Portugal. There were no clouds over the location and surrounding areas. As these fires were progressing, smoke plumes were observed with their tops at around 6-7 km a.m.s.l. However, as a sea-breeze front arrived at the buoyancy sources it was observed an outstanding vertical growth of the plumes. One of these developments was particularly analyzed and it was found that the plume topped at nearly double that altitude in less than 60 min. As a result of this interaction, an impressive pyroCumulus cloud formed. This process was analyzed using weather radar with Dual polarization capabilities.