Ash plume of Popocatépetl volcano (Mexico, 5426 m) detected by the OPGC Doppler radar (VOLDORAD 1) at Tlamacas station (4000m a.s.l.), about 5 km North of the summit. The radar is continuously monitoring the explosive activity of Popocatépetl in the framework of a collaboration with Centro Nacional de Prevencion de Desastres (CENAPRED) and Instituto de Geofisica - Universidad Nacional Autonoma de Mexico (UNAM). This project was funded by CNRS-INSU CT3, OPGC, Lab. Magmas et Volcans UMR 6524 and Institut de Recherche et Développement.