Grímsvötn, the biggest and most active volcano on Iceland, located under Europe's largest glacier Vatnajokull erupted on May 21.
Grímsvötn started erupting on Saturday, sending an ash plume 12 miles high into the sky and closing Keflavik, Iceland’s main airport. Grímsvötn hasn’t erupted since 2004, and Iceland’s Meteorological Office said the volcano began as subglacial eruptions, which quickly broke its ice covering and sent smoke and ash 65,000 feet into the air. The ash plume is expected to drift east and north away from Europe, with no expected impact on the European airspace for at least the first 24-48 hours. The Grímsvötn eruption is larger than last year’s Eyjafjallajokull eruption, but is not likely to have the same massive effect. To which extent this projection turns out to be true is highly dependent on a combination of the continued force of the eruption and the direction of the winds.
Keflavik airport and the air space over Iceland was closed and will remain closed at least until mid day Monday. If you're among those affected by flight cancellations this weekend or Monday, the Icelandic airline Icelandair continuously updates the situation at its website, Flight disruptions due to volcanic activity in Iceland