Heavy Snow — Juneau Borough and Northern Admiralty Island, Alaska

2020-11-01 to 2020-11-02 · Juneau Borough and Northern Admiralty Island, Alaska

Event narrative

Rain changed to snow around noon on the 1st and quickly accumulated 7 inches by 5 PM as measured by an NWS Employee on Douglas Island. Snow continued through the night and occasionally mixed with ice pellets and freezing rain the morning of the 2nd. The greatest snowfall measurement was 11.5 inches at midnight by a CO-OP observer at Lena Point. Multiple power outages were reported between the early evening of the 1st through the morning of the 2nd.

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 926248. Narrative written by the NWS forecast office that issued the report.