Trick or Treat: The Winter Forecast

This past Saturday, meteorologists gathered at OMSI for the 19th Annual Winter Weather Forecast Conference. They gather to share their predictions, forecasts and discuss when the ski season should start in earnest in the Pacific Northwest.

The following summary of the event was sent to CRESA by Steve Pierce:

La Nina is back and she may be handing out plenty of adverse weather across the Pacific Northwest again this winter. For the second year in a row, a standing room only crowd of 365 attendees descended on the Oregon Museum of Science and Industry (OMSI) in Portland over the weekend to hear regional weather experts prognosticate the winter ahead. Some attendees traveled from as far away as 200 miles in order to hear the details.

All five forecasters who presented at the conference were in nearly complete agreement that La Nina is likely to bring above average snowfall to the Cascades again this winter, as well as an increased chance for lowland snowfall in the valley.

Last winter featured two notable cold spells and low elevation snow events in late November and late February. It also featured lowland flooding along the Sandy river and record setting snowfall in the mountains.

Will those kinds of conditions repeat again this winter? Most forecasters played it safe with a broad-brush La Nina forecast, which calls for cooler and wetter than normal conditions across the Pacific Northwest. However, a few forecasters went out even further, suggesting that February may end up being the coldest month of the winter, with the best chances for low elevation snow and perhaps an arctic outbreak.

Meteorologist Jim Little, who presented Saturday at OMSI, pointed out that the best analog (similar) year to the current trend is the winter of 2008/2009. That winter featured 24" of snow at the Portland International Airport, including a new record for the most snow ever received in the month of December. Nearly 10" of snow was still on the ground on Christmas day 2008. Winter of 2008/2009 recorded the most snow of any Portland winter since 1968. Little also pointed out that analog years do not guarantee an exact repeat again this year, however odds are increased over that of a non-analog year.

As billed, the crowd was also serenaded by former Oregon state climatologist George Taylor and his self-proclaimed "La Nina" song, strummed to the tune of "my girl" by the Temptations."