Good Saturday afternoon to everyone, hope your weekend is off to a great start.
A couple days ago we were tracking severe weather ahead of a strong cold front. That front moved through late Thursday and has delivered to us a much cooler weather regime as we start the month of November. And from all indications the first half of this month looks to have the potential of being quite chilly as waves of cold air will come crashing down from the Polar Regions of the Northern Hemisphere.
One of the things we look at this time of the year is how much snow pack has already formed well to our north along the Arctic. As you can see with this image most of Siberia is covered in snow here at the start of November along with an increasing snow cover in Northern North America.
This is running a bit ahead of schedule compared to the past couple years which has our weather team intrigued as to what the consequences may be in relation to the winter here in the United States.
So, the next question is: How can you get that cold air transported south?
It takes a couple different things to happen. First, you need a favorable setup at the upper levels of the atmosphere to tap into the cold air source of the Arctic. All indications are that we will be entering into a pattern that may do just that.
Here is a look at the weather pattern in the upper atmosphere that is expected to form. Notice up in Alaska, a strong upper ridge is projected to develop and linger along the West Coast of North America for the week. That will help promote "cross-polar flow", which in simple terms means that air from Siberia will cross the Arctic Circle and enter into the jet stream across North America. That cold air has only direction to go...and that's southeast!
With the conditions at the jet stream level cooperating, the surface features that will drive the cold air into the United States will start to evolve.
Here locally, we will remain on the chilly side of things this weekend and then a slow moderation come Monday and Tuesday. But with that said you can already see the next cold blast on the model data that has a destination for the Eastern US late next week. A massive 1040 mb surface high will be diving into the Northern Plains States, that will drive a strong cold front through the middle of the country by mid-week.
That high will continue to move through the Plains and Midwest and by late this week will be positioned just to our north over Pennsylvania. That will drive a frontal boundary into the Southeast US by then meaning a reinforcing shot of below normal temperatures. This front may also being our next shot of rainfall as well.
As you can see on the image above, addition strong surface ridging continues to build in Northwest Canada next weekend and that will likely result in additional cold air intrusions after the current 7-Day Forecast.
Confidence is growing quickly in this setup being a prolonged weather pattern through the first half of November. One has to wonder if the severity of cold in subsequent cold air intrusions will increase given the above normal snow pack already in place in the Arctic Regions?