Unusual weather caused flooding in Kotzebue, Alaska, with water levels rising five feet above the normal high tide line due to a weather system that moved up to the Bering Sea from the tropics. The flooding was caused by a 990 millibar low, which would be like an everyday low in the fall, but the conditions surrounding that low were what made it into the perfect storm. Coastal flooding itself isn't unusual in Kotzebue, but the time of year is what made it stand out. It's October and November storms that usually bring these conditions.