#WAWX 1/ Could the great winter of January 1950 happen again in Seattle and the Pacific Northwest? I sometimes have this discussion with people I know and work with. After looking at the data closer I think the answer is complex. Let's examine:

2/ Jan 1950 saw Seattle with 19 days of measurable snow. This type of month and overall cold might be hard to duplicate. Due to changes in Climate, we have had fewer arctic intrusions and it's become noticeable especially in the last ~30 years or so. Arctic air has a tough

3/ path into the Pacific NW. It takes a deep arctic air mass and the correct trajectory of the air to bring our truly epic arctic intrusions into the region. Any change in depth of arctic due to loss of sea ice and general global warming is going to make powerful

4/ arctic blasts an even more rare occurrence in Western Washington. Now while we have seen arctic blasts less frequently, they still do happen. Looking at the Jan 13th 1950 snowstorm that crippled Western WA, the arctic high wasn't noteworthy.

5/ Here is the setup: a 980mb low takes a perfect track, throwing a large gradient from interior of BC into Oregon of OVER 45mb! But notice something else here: The arctic high itself is not very strong.

6/ The arctic high of 1030mb north of YWL is something that is a rather common occurrence during winter months. This storm is a product of perfect tracked, powerful low at the peak period for snowfall in the region.

THIS type of storm can happen again, in my opinion.

7/ While we may never see a month like January 1950 again, the individual large snowstorms and shorter term arctic intrusions themselves are still a threat to Western Washington from what I've seen scouring the data of 1950-2020

8/ I've talked to quite a few people about these scenarios and maybe this discussion will get a few more involved. I'd love to hear new thoughts.