It’s not a Game of Thrones reference it’s a 7 day forecast reference. Winter’s coming! After a brief hiatus we’re getting ready to rock some cold and maybe some snow for the last 2 weeks of January.
It’s easy to see the cold front that will be the beginning of the end of our vacation from winter. While we’ll see a spike in morning temperatures on Monday it’s all downhill from there.
What is slightly intriguing is the fact that this front will get hung up to our south over the Mid Atlantic. Our models, for the most part, keep the front offshore and keep us dry Tuesday and Wednesday but there are some hints that moisture may come north just a bit for a period of light snow or light mixed precipitation Tuesday or Wednesday (or maybe both).
Last week I blogged about the Tuesday storm potential. While it always looked minor I thought a colder/more offshore solution would verify. At the time some of our models were bringing the wave up through Binghamton, NY and giving us rain! The colder and more offshore solution will verify but it may be far enough offshore to give us nothing more than a glancing blow of clouds and flurries. We’ll have to watch the models over the next few runs but there’s a low probability of a period of accumulating snow from one or both of these waves.
Beyond Tuesday temperatures are going to drop off gradually. By Friday it appears that we will see below normal temperatures as cold seeps out of Canada.
The last 7 days have just been brutal for winter/snow lovers. A gradual melt-down and warm-up with an ugly -PNA trough and a southeast ridge that has been flexing its muscle has been tough to take.
While the pattern hasn’t been great it’s not an all out disaster moving forward. Some modest EPO ridging and negative arctic oscillation ongoing gives a reason for hope. Models are emphatic (operational and ensemble guidance) that a strong -AO will displace the polar vortex to around Hudson Bay and bring an extended period of at or below normal temperatures to New England. Brutally cold weather is possible across the U.S./Canadian border though at this point the serious cold will probably stay north of us.
Here’s the evolution on the Euro ensemble with the day 6-10 day mean and the GFS ensemble day 11-15 day mean. It’s especially important to watch the changes across the North Pacific and west coast.
It seems to be we have the potential for a winter storm next Monday/Tuesday as the pattern reloads. It will be tough to time out the individual shortwaves but I see that time frame as a potential target.
What is interesting is that the +PNA in the D6-D10 time period is replaced by a more neutral PNA look beyond day 10. The strong -AO remains. This pattern does bear a resemblance to DJF ’93-’94. Take a look at the 500mb height anomalies from that winter (which was a winter-lovers dream!).
I’m quite confident that the cold is coming with a period of AOB normal weather. The snow probably isn’t far behind either with a pattern that will favor redeveloping clippers even with the absence of a -NAO signal thanks to the ’93-’94 wintry appeal.
Looks like a fun stretch – stay tuned!