Winter Storm — Greater Portland Metro Area, Oregon

2021-02-11 to 2021-02-13 · Greater Portland Metro Area, Oregon

Event narrative

This was a transition event for the greater Portland metro area, with wide variation in snow and ice totals across the zone. Snowfall totals tended to be highest near the Columbia River, while the south and west metro saw much less. General 1-4 inch snow totals in the south and west metro, but up to 10-14 inches near the Columbia, all the way down-river to Scappoose. There was a prolonged period of freezing rain in southern portions of the metro area, resulting in massive power outages which persisted for several days in many cases. Ice accumulations ranged from 0.25-0.50 in downtown Portland, with amounts generally increasing closer to 1 inch in the south and southeast metro. The heaviest ice accumulations appear to have been around Oregon City, West Linn, Wilsonville, and Sherwood, where up to 1.25 inch of ice was reported. Another slug of freezing rain came on the 14th and early 15th, this time mainly impacting downtown and eastern portions of the metro while most western areas changed over to plain rain. This latter event was handled with a separate Ice Storm Warning.

In the Portland area over 250,000 customers across the metro area were without power due to ice, snow and winds. Key impacts included collapsed roofs and awnings, widespread tree damage, power outages, vehicle accidents, and road closures including I-84 east of Troutdale.

Wider weather episode

This was a major, widespread, multi-faceted winter storm that caused major problems across the northern 2/3 of our forecast area, even (and especially) in the lowlands. Impacts were felt as far south as Albany. WFO Portland measured 10.1 of snow, followed by roughly 0.75 of ice. Significant impacts to infrastructure occurred, with over 400,000 people losing power at some point during the storm. The area impacted the hardest appears to be the southern portions of the Portland metro, south through Oregon City and Silverton and as far south as Salem and Aumsville. Polk County was hit hard by ice as well, with 1.00 to 1.75 of ice reported. Some people in these areas hard-hit by ice lost power for over a week.

Source: NOAA Storm Events Database, event_id 946327. Narrative written by the NWS forecast office that issued the report.