Huge pyroclastic flows in all directions and an ash cloud close to 50 thousand feet!
It all began yesterday afternoon with a series of powerful explosions that produced an ash column exceeding 40,000 ft (13 km ) altitude, and pyroclastic flows up about 8 km in length.
At 17:00 local time, two moderate-sized explosions generated ash columns rising to about 5 km (3 miles) above the summit, and produced pyroclastic flows that descended about 500 meters northeast and north of the western flanks.
A larger explosion about 39 minutes later propelled ash to about 8 km above the volcano (ie 40,000 ft / 13 km altitude).
In the field of Chacauco , the fall of tephra caused total darkness .
http://piccolaeraglaciale.wordpress.com/2014/02/02/ecuador-enorme-eruzione-del-vulcano-tungurahua/
Thanks to Nick Mangin and Alessandro Decet for this link