Monday Weather Update: Winter Is Coming

Good morning. I hope everyone had a nice Thanksgiving weekend. I have had several posts over the last few weeks discussing how winter should get off to a fast start this year compared to previous ones. I based this on the work I did in my winter outlook.  Now that December is in our sights, I can say that after a brief 7-10 days of mild weather winter will come in strong starting around December 8th. In particular, the period from the 8th-18th has the best chance to give us our first shot at accumulating snow which increases the chances of a white Christmas this year.

Summary:

• More seasonable/milder weather on tap over the next 7-10 days
• Winter then kicks in for real after December 8th.
• Expect colder conditions and chances at snow to fall as we move towards Christmas
• This follows the ideas laid out in my winter outlook for December
• Remember, I still do expect the core of the winter to be off the coast this year
• Regardless, everyone should get in on some action with the pattern that will evolve in 10 days. 

This pattern change is now becoming well advertised as every major model is showing the same thing for week 2 in December and beyond....

The images above show the European, Canadian and GFS models for the second week of December. As you can see there is very strong agreement between all of them. They all show the factors I highlighted in the last image. This is a textbook setup for a colder and stormier eastern 1/3 of the country. Any energy that gets caught up in a pattern like this will likely consolidate in the east increasing the chances for unsettled weather and snow for this period. Of course, this is not a guarantee but the chances are much higher than normal. 

In addition to this, we also are seeing projections that the strasophere (highest levels of the atmosphere) will warm over the next 2 weeks. This is a signifigant factor as well as a warming strasophere causes the polar vortex to move off the pole which also increases the chances for colder air to funnel south into the lower latitudes. You can see the warming that is projected below. Notice the polar vortex getting pushed off center and potentally split...

When the polar vortex is knocked off center and potentially split, the effects are normaly felt 2-3 weeks later as what happens above has to work its way down into the lower atmopshere. The end result tends to be higher than normal pressures at the pole and lower than normal pressures/cold air in the lower latitudes. The fact we are seeing this being projected only strengthens the case for the pattern change being advertised by the models. A factor to keep a close eye on for sure.

Now I have shown on a few occasions what my forecast was for December back when I put out the winter outlook in October. You can see below what it was...

It will now be interesting to see how this all comes together. Enjoy the milder weather over the next week or so. More active times are on the horizon! Just maybe we can pull off a White Christmas.


More to come.