Wet and wintry weather has caused widespread disruption across the Pacific Northwest of the United States, with the heaviest snowfall to hit the area in several years.

The storm started on Sunday night and made for a nasty Monday morning commute across the greater Seattle area.

The snowstorm that blanketed Seattle and Western Washington State, causing huge travel delays and major power cuts. Dozens of schools were forced to close, much to the delight of many of the pupils.

Dozens of flights were cancelled at Seattle-Tacoma Airport due to snow and ice and more than 90,000 customers found themselves without electricity at some stage.

Snow accumulations amounted to 36cm in places. It is still snowing and forecasters predict as much as 75cm of snow could fall in the Cascade Mountains by the end of Tuesday.

Snow is actually quite rare in Seattle because it is so close to the relatively warm waters of the Pacific Ocean.

Portland was also badly affected, and there were concerns that the city would be hit by a major snowstorm. Those concerns did not materialise because temperatures remained high enough above freezing.

In the event, Portland, which is a very wet place at the best of times, had more than half a month's worth of rain in just 24 hours. Some 52mm fell on Sunday, making a total of 80mm in three days. The February average is 80mm.

It was even wetter in the state capital, Salem, with a downpour of 64mm on Sunday, and 122mm in three days. That easily surpassed the February average of 116mm.

Many rivers in the western side of the state have been pushed close to flood levels. More rain is forecast for much of this week so flooding is possible before drier weather arrives this weekend.