With a second earthquake striking yesterday, this time a magnitude-4, Iceland’s Met Office was prompted to raise the threat level for a Bárðarbunga eruption to “orange.” With an unpredictable eruption looming on the horizon, concerned Europeans and ex-pats are all asking the first question that naturally comes to mind: “How will this affect my travel plans?” The answer, as reported by Tom Clarke of London’s Channel 4 news, is that it won’t – even if it erupts, the ash cloud is unlikely to be large enough to halter air travel anywhere other than the immediate area.

Bárðarbunga, which last erupted in 1864 and is Iceland’s 2nd-largest mountain, has been besieged by earthquake “swarms” since Saturday, August 16. As of this morning, about 2,500 quakes have been detected by the Met Office, with 950 registering at a magnitude-3 or higher. The quakes originate from two “clusters,” one to the north and one to the east of the caldera (the northern cluster is already subsiding, scientists say).

Those cluster patterns are the reason an eruption likely wouldn’t trigger an ash cloud that would spread across Europe: The kind of magma that produces super hot, explosive eruptions and super-fine ash plumes is usually found in the heart of the volcano. Because any eruption would likely happen away from the heart, any ensuing ash would be too dense and low to spread very far.

The fears of protracted travel plans aren’t without merit: LiveScience reminds us that the 2011 eruption of Iceland’s Eyjafjallajökull volcano famously closed airports for six days, stranding passengers and costing airlines $1.7 billion in lost revenues.

All told, the volcano shouldn’t be much of a risk to Icelanders – the area surrounding it is uninhabited, and roads leading to Bárðarbunga have already been closed. Flooding is a threat (as the volcano sits atop a glacier), but the Met Office reports that as of this morning, “no signs of migration towards the surface or any other signs of imminent or ongoing volcanic activity have been detected so far.”

Still, volcanoes are unpredictable things, and the fact that Bárðarbunga last erupted 150 years ago means that scientists know relatively little about it. Anything is possible.