EXTREME AVALANCHE RISK WEDNESDAY AND THURSDAY: Level Four conditions forecast for Longyearbyen vicinity and East Svalbard due to wind and large amounts of unstable snow

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Map of 13 avalanches near Longyearbyen and Barentsburg in past 72 hours by NVE

Update 5:40 p.m. Tuesday: A large avalanche  at in Ottofjellet, about 15 kilometers northeast of Longyearbyen, was reported late in the afternoon by a snowmobiler, according to The Governor of Svalbard (see photo below). A Level Four risk alert is now in effect for the entire region.

Original story: An extreme risk of avalanches is forecast Wednesday and Thursday for some of Svalbard’s most popular spring excursion areas – including the vicinities of Longyearbyen and Barentsburg, and east Svalbard – due to increasing winds and significant accumulations of unstable snow, according to the Norwegian Water Resources and Energy Directorate.

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The avalanche risk level for Wednesday and Thursday is expected to be higher than existed most of the past two weeks, when conditions were still dangerous enough to result in evacuations and traffic bans in Longyearbyen. Chart by the Norwegian Water Resources and Energy Directorate.

A Level Four (“high”) risk level – one below the maximum – is forecast for both regions, according to the directorate’s tracking website. Conditions have mostly peaked at Level Three during the past couple of weeks, which has still been severe enough for two evacuations to be ordered in Nybyen and several large avalanches to occur that were observed by snowmobiling groups.

“An increase in wind will lead to wind loading on a very unstable snow pack,” notes the forecast for the Nordenskiöld Land area that includes Longyearbyen and Barentsburg. “Avoid and keep distance from all avalanche terrain. Naturally triggered large and even very large avalanches likely.”

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A large avalanche on Ottofjellet, about 15 kilometers northeast of Longyearbyen, was reported late Tuesday afternoon. Nobody was caught in the snowslide. Photo by The Governor of Svalbard.

A similar forecast for east Svalbard predicts “large and even very large avalanches likely due to heavy wind loading on an unstable snow pack.”

The weather forecast for the region Wednesday and Thursday calls for winds guesting to nearly 50 kilometers an hour – well below gale-force winds reaching twice that during the weekend – and modest snowfall most of Wednesday and late Thursday.