Arctic Express Looming
Hello everyone. Well, I have looked at all the latest data over the past 48 hours and it now appears increasingly likely that the Pacific Northwest will see the arrival of a very cold air mass this coming week that has the potential to set new record temperatures across many areas. Computer guidance is coming into better agreement with the evolution of cold arctic air that is forecast to slide into the Pacific Northwest from Canada beginning Wednesday. The “BIG 3″ models (Canadian, Euro and GFS) are all in agreement once again. In fact, the Euro was downright nasty with the cold and snow it was showing. Only time will tell what the final outcome will be. But the odds are certainly increasing in my view, as of this (Sunday) morning. The timing of this change to much colder weather appears to be settling in on early Wednesday morning and lasting into next weekend. It is still to early to tell exactly how much low elevation snow will accompany this system and exactly how cold the air mass will be. But if the pattern evolves as presently forecasted, this has the potential to be the coldest air mass to invade Portland and Seattle, for this late in the season, since March 2nd 1989 when the Portland International Airport reached high temperature of just 35 degrees, setting a new record for the date. Most of the coldest daytime temperature records for the Portland International Airport are at or just under 40 degrees over the coming week. Portland’s record low temperatures for the upcoming week are mostly in the lower 20’s. The potential exists to challenge several of these records. The record highest single calendar day snowfall at the Portland International Airport (1940-2011) in the month of February is just over 6″ set on February 19th 1993. Other notable Portland February snowfalls (after February 19th) include 2.0″ on February 24th 1994 and 3.2” on February 28th 1962. The evolution of this system will be watched closely over the coming days for any deviation that could have a significant change in the overall outcome.