Tuesday, February 2, 2016

Tuesday Morning Discussion: More Evidence of Next Week Heating Up (Not Literally)

Good morning. As we continue to hone in on our colder and stormier pattern for next week, certain details will start to become more clear. Some trends have started to emerge over last 24 hours and if they continue, we could be in for an action packed week!

Before I begin, now that January is in the books, here is how my January forecast did that I put out in October..


Overall not too bad. But New England is very snow starved right now and that needs to change. The big storm helped the Mid-Atlantic and it wouldn't take much more to get 30% more than normal (my forecast) for those spots hit by the storm. 

I expect this for Feb (our banner month)..



In any event, we will evaluate how my whole forecast did in the spring. Back to next week...


  • A very active and stormy period is in store for next week
  • Cold arctic air moves in this weekend with the potential for storm(s) to develop through next week
  • A split flow in the jet stream will be a driver in this
  • My first focus is Monday into Tuesday
  • Details are starting to emerge but we have a lot more data to study before any forecasts can be made

Here is a diagram that sums up my latest thoughts from the European Ensemble..



Over last 48 hours the trends have been to move the western ridge position more east along with the development of a 50/50 low. This is huge as it supports energy to consolidate along the east coast. The diagram above shows how this happens. At the surface you can see the model is projecting that low pressure center to develop offshore and move up the coast due to the northern disturbance diving down and steering it along with blocking from the 50/50 low.  Below is the surface projection..



48 hours ago this was not projected due to the upper air placement being much further west. The next image shows this. Old is left new is right..



As you can see drastic changes in the position of the ridge and trough. As the days go on we will have to work out the finer details, but all models agree a storm or storms could develop from Monday through Friday of next week. At this time I want to focus on the period Monday into Tuesday. 

Due to the split flow in the jet stream and massive surge of arctic air we really could be looking at multiple disturbances merging with the sub tropical jet which would mean waves of precipitation all week. 

You can see how impressive this split flow is projected to be. Talk about cold air meeting warm air!



Thats all for now. We are starting to come a long way from my original post a week back when I started this case study..


More later. 

6 comments:

  1. Just took a quick look at this AM's GFS, CMC/GEM and Euro . . . still appears to be a lot of disagreement as to how and where the jets interact, when / where / how deep the central-eastern trough is gonna be, how fast it's gonna move, etc. The key player for next Monday-Wednesday appears to be a coastal storm, but each model is playing it differently. Euro seems to put it pretty far out to sea, GFS and CMC close enough for a mix of rain and snow (but to different degrees). From the telecom side: OK, definitely a spike going on in polar strat temps, and the AO and vortex are gonna be degrading soon. But the AO models still seem uncertain exactly how quickly the vortex is gonna respond to this upper air warm up. The other telecoms however aren't all that supportive of a classic on-going winter pattern. Yes, PNA is gonna support a western ridge and eastern trough, but the NAO looks to stay positive, the EPO too. And the MJO is just wandering in the Pacific, doesn't look headed west anytime soon. Yeah, there's gonna be some N/S jet action, but the zonal trend might remain pretty strong. FWLIW, I'd guess that early next week is still jump ball, but for later next week and the president weekend, it's definitely back to scarves, hats and gloves. For a while, anyway -- Nino is declining but not as fast as thought. And yea, there's gonna be snow this month, but as to another major event . . . again, jump ball. Oh, yeah, forgot, Super Bowl time, need a football metaphor -- OK, say a 48 yard field goal attempt. Enjoy the game! Jim G

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    1. It is a jump ball but the H5 trends on the ensembles last 3 days are impressive. The mean trough has shifted more east, the ridge is more pronounced and we have enough ridging in the Atlantic to make things interesting. IF we get all this energy to tighten up more, things can really go boom.

      For the long range we have conflicting signals but the SSW and the projected displacement of the vortex does support eastern cold. To me this is a huge factor and trumps the MJO. After this arctic surge next week, I think we might see a brief warm up mid Feb but late Feb into early march this pattern gives us its last punch. Nino is still strong but more to the west and the jet is at peak seasonal strength. Couple that with the SSW and I need to put money on active Feb.

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  2. I hope that storm puts snow into Elmira, NY so we can get past the 4" snow total for the year-any thoughts on the snow's westward coverage?

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    1. That solution is def on the table at this time. A low tucked into the coast which is projected by some models and ensembles gets you in play.

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  3. If the New York City area is predicted to only get 30% above average snowfall, that would be only about another 10 inches is expected to fall on top of the 27 inches that fell so far.

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    1. That is correct, I was banking on around 2 big storms this year. We got one we need one more.

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