Blizzard — Haines Borough and Lynn Canal, Alaska

2020-11-01 to 2020-11-02 · Haines Borough and Lynn Canal, Alaska

Event narrative

The Haines ASOS reported heavy snow and visibility quickly falling to 1/4 mile at the beginning of the event. Meanwhile the wind was already reporting gusts of around 30 mph and marine points further south were reporting much higher winds. These conditions continued into the next morning with the ASOS exceeding wind gusts of 35 mph after 1 AM. Haines DOT reported blizzard conditions, blowing and drifting snow on the highway. Haines Customs reported 14 inches of snow in 24 hours and the Co-Op and spotters around town and Mud Bay measured 16 to 22 inches with mention of blowing and drifting snow.

Wider weather episode

Deep low pressure tracked northward along the outer coast causing impacts across Southeast Alaska beginning Halloween night through November 2nd. High Winds were felt over the outer coast and heavy rain caused rivers to rise out of their banks across the southern half of Southeast Alaska with minor impacts. The ground was already saturated by moderate to heavy rain leading up to November 1 and 2 with amounts ranging from 5 to 9 inches. Multiple mudslides occurred near steep terrain after rain amount of 3.5 inches over 36 hrs along with wet antecedent soil conditions. Tight pressure gradient along the Coast Mountains resulted in strong northerly outflow winds and cold air to push southward through the northern inner channels resulting in heavy snow.

Source: NOAA Storm Events Database, event_id 926270. Narrative written by the NWS forecast office that issued the report.