#43YearsAgo at #MSH: During 1980-86, scientific understanding grows by leaps & bounds. Better monitoring systems show volcanoes are inherently restless; scientists share a commitment to communicate hazards. Lessons learned from MSH must not—and will not—be forgotten. #volcano #usgs

#43YearsAgo at #MountStHelens: May 30, 1980
Lilies emerge from the ash. Restorative part of cycle, repeated many times at Mount St. Helens & other Cascade volcanoes, has begun. Travel in NW nearly normal. Scientists focus on hazard evaluation & how to live with active volcanoes. #volcano #usgs

#43YearsAgo at #MountStHelens: May 29, 1980
Activity has declined. The eruptive plume rising from the volcano's crater is a light gray mixture of ash and steam. Tiltmeters record no anomalous ground tilt. Seismicity is at its lowest since activity began in mid-March, 59 days ago. #volcano #usgs

#43YearsAgo at #MountStHelens: May 28, 1980
WA Governor accuses people killed in eruption of violating restricted zones. This is untrue for nearly all. People caught up in sideways blast skirted no roadblocks. They did nothing wrong. #volcano #usgs

#43YearsAgo at #MountStHelens: May 27, 1980
On I-5, ash from May 25 eruption makes driving tough. State Patrol sets emergency speed limit of 25 mph but drivers impatient. Truckers communicate by CB, maneuver rigs to form moving roadblocks. Drive speed limit to prevent accidents. #volcano #usgs

#43YearsAgo at #MountStHelens: May 26, 1980
Helicopter settles gingerly on deposit in valley & scientists get out to probe temperature. Nearly a week later, ash is still 300° F, 2 ft down. Chunks of glaciers entombed in lahar. Air full of strange smells; wood cooking in ash. #volcano #usgs

#43YearsAgo at #MountStHelens: May 25, 1980
Early AM eruption sends ash to Portland/Vancouver (as much as 1/4 in). While ash falls, rain starts, roads slick, airports closed, phone/power out. "Everybody started freakin..." stampede to store to stockpile food, supplies. #volcano #usgs

#43YearsAgo at #MountStHelens: May 24, 1980
Seismologists scour EQ records trying to find the pattern that would have foretold the eruption. There is none. Huge seismic buildup in March seemed to be wad of magma intruding into volcano. That event, in time, caused all others. #volcano #usgs

#43YearsAgo at #MountStHelens: May 23, 1980
In eastern WA, powdery ash blows everywhere. People stranded, motels full. Sheriffs start slow passage of motorists on I-90 West, releasing 1 car every 4 min. Drivers told to drive 20 mph. Stirring up ash reduces visibility. Accidents. #volcano #usgs

#43YearsAgo at #MountStHelens: May 22, 1980
President Carter flies over shattered houses, flood-swept lower valley, downed forest, debris avalanche; an explosion equating to 10 million tons of TNT. Carter remarks: “...moon looks like a golf course compared to what’s up there.” #volcano #usgs