20% of its snow and ice cover was melted by Pyroclastic flows. Lahars 50 meters thick travelled at speeds of 60km per hour down valleys carrying debris.
Evacuations were slow due to it being dark, thunderstorms, no drills and little means to leave the area
Many where told to stay within their houses and organisation of evacuation was poor.
Destroyed villages and killed over 25,000 people.
Relief workers couldn’t move through the thick mud to reach the town of Armero and finally arrived 12 hours after the eruption when many had died.
Name of the volcano that caused a delay lahar in Columbia in 1985
