That morning , shortly before 8 : 00 a.m . , Mount Pelée erupted , venting a searing mass of pyroclasts ​ — ash , cinders , obsidian , pumice , and superheated gas — ​ that ranged from 400 to 900 degrees Fahrenheit [ 200 - 500 ° C ] .
That morning , shortly before 8 : 00 a.m . , Mount Pelee erupted , venting a searing mass of pyroclasts ​ — ash , cinders , obsidian , pumice , and superheated gas — ​ that ranged from 400 to 900 degrees Fahrenheit [ 200 - 500 ° C ] .