Monday, December 28, 2015

Mondays Weather Discussion: Winter Storm on Tap for New England Tonight

Good morning, looks like everything is on track for the first winter storm of the season. I am keeping my map from Saturday morning due to no major changes. Here are my updated highlights..

  • Only part of our forecast area that has a shot at freezing rain and sleet is north to NW NJ into southern NY and CT.
  • Central and South Jersey will be all rain
  • The frozen precip that does fall in Northern zones will change to all rain quick by daybreak 
  • For elevations over 700ft temps will stay below freezing longer so be careful of frozen surfaces 
  • Ski country I'm VT,NH,ME does decent with 4 to 8 inches of front end snow before changeover to sleet by mid morning Tuesday
Here is my map..

National weather service does have advisories up for northern zones..

This all is over by tomorrow afternoon with rain.

So let's move on to discussing the big pattern change coming our way. To review, here was my original thesis on this:

  • Mild December would give way to colder January and February. February will be banner month.
  • This was due to projected stratospheric warming along w ocean temperature patterns per my winter outlook.
  • The el nino will only enhance the moisture on the field via the subtropical jet meaning changes for big storms as winter matures 
  • Key is a western ridge w moisture cutting underneath. If we have blocking in place via the Atlantic it's game on
So let's look at how this is evolving..

Looking above you can see updated projections on our upper air pattern in January. A large ridge of high pressure is projected to form over the west into AK. This is huge as it could mean we have arctic air directly injected into the United states! Notice also we have all the blue underneath. This is an active storm track due to the el nino keeping the sub tropical jet very alive. Now don't get too excited yet about big storms. We still need to see ridging or high pressure form near Greenland which will take some more time. However this initial pattern can feature more clipper like systems meaning the chance of light snowfalls first 2 weeks of Jan. 

Now let's also see how our stratosphere is evolving. Warming has already started at some levels and all indications are it will continue and put big pressure on our polar vortex. This is huge as I always said we needed to see this happen below..

Notice how elongated it is and pushed off the pole. This will have drastic impacts as January progresses. The net effect of this stratospheric warming is a negative Arctic Oscillation which means high pressure at the pole which unlocks all cold air. Check out the projections on this below. Very impressive and would have HUGE implications on cold in the United States. Opposite pattern of what we have had from Nov-Dec that caused the warmth!

Here is an estimate of temperatures next 16 days. I expect temps can end up being lower than what's shown at the end of this period..

So overall I love what I am seeing. It makes me confident in the forecast I laid out in October. I think we are in for a lot of fun this winter. Remember I still think the big storms are a few weeks away but until then we will all enjoy the transition of this season. Or at least I know I will. 

Thanks for reading.


  1. I'm not buying it Willy, not wholesale anyway. I saw some early December forecasts by snow-oriented analysts who said that Nino might be dying, and thus December would finally turn cold. OK, still waiting for that to happen. This Nino is a powerful brat, it ain't going out easy. The latest Pacific SST anomalies seem to be holding up, even in coastal region 1 and 2 (and the sub-surface anomalies near the coast are also still pretty strong). And your friend the Pacific Blob ain't doing so good right now either. Yea, you're gonna get some digs in January -- in 2 weeks the NAO will be neutral or negative, the AO will be negative, the PNA is positive, MJO is heading into the Pacific, your stratosphere will be nice and toasty, all set for some sudden warming breakdowns of the vortex. But that Nino is gonna just keep punching for a while. So sure, some real winter cold and even the white stuff will be in the mix for us. But the NWS isn't budging much from their JFM temp anomaly forecast; we're still in a positive anomaly zone by a comfortable margin, as far as they are concerned. Sure, the December blowtorch is going out, but my own (highly unprofessional) hunch is that January and February will be a roller-coaster between a leaky polar vortex and continuing Nino warmth. And March may be the Arctic's last stand as Nino retreats, it may be a late spring. As of next week, we're about 1/3 thru meteorological winter. Almost time to start talking about what a La Nina is gonna do to us! But as with any weather talk, I'm of course hedging my bets; the snow shovels and salt are ready to go!!! Jim G

  2. Haha hey you might be right but I think this back and forth will cause a lot of storm activity. I agree with you in the extreme cold, I do not expect that. As I put out i think 1-2 degress below normal when it is all said and done makes sense for our neck of the woods. But the pattern has completely flipped at the pole. That is going to mean arctic air and a powerful sub tropical jet mix quite often. If you get blocking watch out. I am all in on my winter forecast of 30% more snow than normal and 1-2 degrees below normal when it is all said and done. If I am wrong I will give you credit. This will be fun to watch evolve and discuss!