Monday Morning Weather Discussion: Knocking On Winters Door?

Good morning. As the days are shorter and we now enter the 2nd week of November when will we see the first signs of winter? November has started off mild for the most part but this week will start to bring some changes, especially for the weekend. In the long range, signs are starting to develop that the last 10 days of November could result in more of a winter like pattern. This would be huge as it is backed up by the research of my Winter Forecast 2018.


Starting off this week, a cold front moves into the region later today dropping temperatures into the 50's for the week for highs and 30's for lows...

By later in the week a much stronger shot of cold air arrives on Friday. This will be a noticeable change in temps....

With this impressive shot of cold air, temperatures will struggle to get into the 40's for highs Friday into the weekend and hit the 20's in many spots at night. This will the first sign winter is coming!

One major element this year is that the coldest air relative to averages sits on our side of the hemisphere. This is the opposite of last year. This means any arctic intrusions will pack a big punch! The image below shows the air relative to averages to display my point...

Now to the long range. There has been a lot of debate on whether the 2nd half of November would be blow torch warm or cold. I am not in the blow torch camp for a variety of reasons, but mainly because the observations vs what my winter outlook research has produced show signs of coming together.

Lets take a look at long term model projections for last 2 weeks of November...

So many things are starting to show up on the models which can promote a stormy cold pattern. Of course this is just a projection and it may not verify. Nonetheless, this pattern above is similar to what my analogs show for December.....

The key to all of this is the high pressure over Greenland (negative NAO pattern). This buckles the jet stream in the east and causes any energy that's coming in off the west coast to get clogged up. This year the -NAO is key to our whole winter! In addition to this, the other factors I pointed out enhance this. Normally a trough over British Colombia may result in a warm pattern for the east. However, that is not the case when the NAO is negative. Now many argue that the ridge of high pressure (red) over the Bering Sea can result in a warm pattern. In some cases yes, but NOT when there is a negative NAO. If anything that ridge now helps inject cold air into the pattern from the north!


Lets see how this plays out. If this continues to go along with my ideas then we can have an active start to winter come December. Stay tuned!