Erie, Pennsylvania, has declared a citywide emergency after a record 62.9 inches of snow fell over just a few days—an amount that even hardened locals are calling “insane.” Between Sunday and Tuesday, the city on Lake Erie broke the state record for a two-day snowfall, and the storm hasn’t stopped yet. “Roads are dangerous and impassable,” Erie Police declared on Facebook. At least 21 Pennsylvania National Guard troops have been put on active duty. Officials say the snowfall was caused by “lake-effect snow,” when cold air mixes with Great Lakes water to create narrow bands of heavy snow. The National Weather Service said snow is expected to continue through at least Wednesday afternoon.