The cold was impressive all the way to Texas for a 2nd day in a row. While Tulsa, OK endured their earliest freeze yesterday, it was OKC’s turn today. Dallas saw it’s first freeze and 20s got all the way into the Texas Panhandle. The core of cold is now sweeping off the Atlantic coast and recovery is crossing the Midwest heading towards the Northeast after a raw past few days.

After this 3-5 days of impressive early October cold, we’re seeing a brief recovery in heights but as this recovery takes place, arctic air is already regrouping and starting to head back south for it’s second shot. However, this will play out differently.

This time around the arctic air appears to stay mostly in Canada, helped by a large upper-level cut off low which will drop into the Southwest US but for folks living anywhere from Alberta to Quebec, this shot will be stronger bringing snow on it’s leading edge. Following initial snows, readings coming in behind may be some 25-35 below normal.

The chill will push into the Dakotas, Minnesota, the Great Lakes and eventaully Northeast but it doesn’t look to get as far south. Heights remain strong across the US and a lot has to do with that CA low.

While the bitter blast comes acalling, the good thing this time is it won’t last even for Canada as a major pattern shift is coming and will be in full affect by as early as this weekend despite a major cold shot coming beforehand. The trough drops and then immediately slides east across mainly Canada by skirts the Northern tier. This will likely bring snows to northern Minnesota, the Lakes and possibly higher ground of the Northeast.

Interestingly, it’s worth watching what’s going on up in Alaska, the ridge gets replaced by a deepening trough and within that, the coldest air of the season is likely to flood the Last Frontier.

By mid to late week, while the arctic hound drops through Central Canada and slides east into Ontario, Quebec. Height rises are already following in behind and so it’s as this cold is sliding across Canada, major warming is following on it’s heels and by this weekend, there is literally no arctic air to be had over BC all the way to Atlantic Canada. The cold air will be firmly bottled up from the Arctic Circle northwards.

This flattening out of the jet will result in Pacific air free flowing across the majority of not just the US but Canada too and this appears to last well into later next week but the question is, how long does this last? This coincides beautifully with the expected flip to a positive NAO but that, according to the ensembles isn’t going to last. Longer range models shows the return of cold later this month.

Here’s the latest ECMWF run for the next 7 days!

What’s very interesting is if you notice the large storm system that’s pushing into Southern California in the next couple of days, it is this feature that will help delfect the southbound trough and cold pool east. It stops this from getting further south. The system will bring a cloudy, rainy regime to much of California and the Southwest over the next 3 or 4 days.

You can clearly see this feature stopping the cold from dropping into the Northern Rockies and Dakotas proper.

By Thursday, notice the very cold air down to near the US border, this could be an air mass of December proportions for the Alberta Rockies all the way across to Ontario but the motherlode remains at this stage up across northern Manitoba and the NWT.By Friday, the SW low digs and so the ridge over top already starts the warming process into Western Canada. Note the trough dropping into Alaska, this may be the coldest surge yet but the bitter cold is now being pushes southeast through Manitoba, Ontario and heading for southern Quebec. Expect initial snows and then brutal cold. Highs across Northern Ontario may struggle to hit the mid-20s with lows possibly nearing near in spots.

By Saturday, the core of cold reaches Quebec and the Northeastern US but look at the mild across flowing east on the backside. It’s as the cold reaches Southeast Canada, Northeast US that the jet back west is starting to flatten and this is lifting the cold back north.

By Sunday/Monday, the arctic air is back north and Pacific air is flowing freely across southern Canada and the US.