A sinister volcanic disaster could soon strike Earth, posing a threat far greater than any eruption.

Residents of the Pacific Northwest are well acquainted with volcanic eruptions — many cities in the region are overshadowed by seismically active peaks. Such eruptions typically provide residents with time to evacuate, but another type of volcanic disaster can devastate nearby populations without any warning — scientists fear that a catastrophe could occur at any moment, as reported by IFLScience.

These deadly events are significantly more dangerous than eruptions and are known as lahars — essentially, they are massive landslides that occur when initially unstable slopes of volcanoes collapse. Lahars triggered by eruptions are usually predictable, but a much more sinister variety known as "unnoticed lahars" particularly concerns local authorities.

According to experts from the U.S. Geological Survey (USGS), these unexpected landslides can be caused by a variety of factors, including weather, as storms and heavy rainfall can sometimes melt the ice that binds the rock debris and sediment atop glacial volcanoes. Colossal landslides can arise rapidly, leaving nearby communities completely unaware.

Statistics indicate that one-fifth of all volcano-related deaths have been caused by lahars. Recently, the most destructive of these occurred in May 1980 when a flow of rocks and soil cascaded down the slopes of Mount St. Helens, claiming 57 lives.

Recently, USGS experts issued a warning about the potential for far-reaching lahars on Mount Adams, which is currently exhibiting increased levels of activity. Data also show that around 60 lahars have occurred on Mount Rainier over the past 10,000 years.

Staff at the Cascades Volcano Observatory (CVO) have established more than two dozen monitoring stations along the Cascade Range, which stretches from British Columbia to California. These stations are equipped with cameras, strain gauges, and a variety of other instruments to detect ground movements — they provide an incredible amount of real-time data that can help researchers catch a lahar just minutes before it reaches settlements.

However, scientists acknowledge that even if a lahar is detected early, time will still be of the essence. Researchers note that a lahar in Washington State, on the western slope of Mount Rainier, could engulf several towns in as little as 30 minutes.

It is noteworthy that practice evacuations in local schools are a common practice in communities along lahar paths.