Tuesday, February 16, 2016

Tuesday Morning Weather Discussion: Brief Warm up Followed by Big Storm Threat Next Week

Good morning everyone. Yesterday pretty much tuned out as expected. Most areas saw 1 to 3 inches of snow with a coating of ice. We now we await the rain that will move in later today. '

Two things I want to focus on today:


  • The brief warm up we will see over next few days
  • The continuation of this active weather pattern through early March including a big storm threat for middle of next week
    • The overall pattern to support a storm has high agreement among major model groups
    • I will be covering the trends in this extensively over the next week. 

First off, lets cover the boring part. The weather will moderate over the next few days as a ridge of high pressure builds over our area. This is nothing more than the overall pattern reloading for what I believe will be a cold and storm period end of Feb into early March.


However, so not fast. As we enter early next week things get very amplified again along the east. We will have a deep trough of low pressure develop south of the Aleutian Islands of Alaska. This will cause a ridge of high pressure to pump along the west coast which causes a deep through of low pressure to develop in the east. We are 8 days away, but signals from all the major model ensembles are very strong with the overall set up...


Above is the European weather ensemble. I marked out the important features. Please disregard my misspell of Aleutian lol. When we are trying to assess the threat of large storms we need to see certain features have high agreement among models. The three most important factors are: The deep trough south of the Aleutians which supports a big western ridge (centered over MT is key, supports eastern trough more towards the coast), which in turn supports an eastern ridge. In addition I am seeing strong signals of air coming together or confluence over eastern Canada. This is also key because it supports high pressure to stay locked in place over our area. Notice we do not have a big blocking high over Greenland. However, with a piece of the polar vortex there instead, it seems to be pressing down enough to cause that confluence to develop. This almost acts like a negative NAO. 

You can see all three major model ensemble groups generally agreeing on this set up..


Not going to lie, seeing this agreement really has my attention for big ticket potential next week. 

What a setup like this would cause is a storm developing around the Gulf of Mexico and tracking right up the coast around Wednesday or Thursday as you can see below.


So as you guys can see this winter is not over! A big part of this is not only the El Nino weakening but the stratospheric warming. We already had one episode of warming and now the models are showing enough blow to the stratosphere in the long range. This would really increase our chances for March coming in like a lion..

More later.

12 comments:

  1. OK Willy, I see what you're talking about. Possible Noreaster for the 24th-25th. Haven't seen much write up on this yet, but I'm expecting that all the WX-heads will chime in on it by Friday. Actually, Steve Gregory did briefly mention the possibility in his WU write up yesterday. But you're the first I've seen to go thru it in detail. Last night's CMC operational saw it, but the Euro and GFS didn't. However, the GFS had a conversion experience this morning, the 6Z run now indicates upwards of 18 to 24 inches in northern NJ. Last night's probablistics were all over the place, warmer solutions seemed to predominate. The NAO doesn't look like it cooperate with you, but you believe that a wavy, deteriorating polar vortex will do your blocking, keeping an eastern Canadian high in place and slowing up the coastal low, letting it linger over that 40-70 sweet spot. We shall see. The 5, 10 and 30mb temps have come back down over the past 5 days, although I see forecasts for another big spike around the 24th, which you allude to. The 10-14 day AO forecasts have been highly inconsistent over the past few days, looks like a very uncertain situation (although today's AO projection seems to be on your side). Yea, a lot of the long-range gurus are saying that the polar vortex won't get up off the mat after the next 10 mb spike, thus pouring frigid air down over us well past Saint Patty's day. We shall see, the vortex seems to have gotten back on its feet just fine after last week's spike, went + yesterday. Bottom line, I agree with you that the situation for the 24th/25th has big-storm potential, but it's not a lock yet (and neither is the cold March). Need to keep a close eye on the models over the next 48 hours, see if they line up. If the big noreaster does happen, then yes, you would be one of the first to call it. Jim G

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    1. At this time just focusing on a storm forming. Whether or not this is snow for coastal plain obviously is impossible to tell this far off. The biggest thing I like here is that deep Aleutian low and the overall position of the ridge on the ensembles. The models may not agree on the small details but the large scale agreement on those two features alone gives me enough to start talking about this. Not to mention, the active STJ. That lack of NAO will be an issue. Without proper confluence the chances of snow near I-95 do diminish rapidly. Regardless, still to early to work those details out. Will be fun to track this threat, I am sure there will be more drama to follow. Euro had it today will prob loose it tomorrow. We shall see, thanks for reading

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  2. You may be correct on an East Coast storm next week. However, I have to go with the trends so far this winter, either rain or no snow for the areas that have not had much snow this year. We've had a Rubik's cube of combinations for missing snow in Elmira/ Binghamton, NY an the other snowless areas of the East.

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    1. I feel your pain. As the old saying goes "it snows where it wants to snow". There is a chance here however that this can trend more inland, especially of that mean ridge trends more east. We should know more by the end of this week. Thanks for reading.

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  3. Mid day Canadian, GFS and Euro runs not too bullish on a high-impact coastal storm for 24th / 25th. In fact, the Canadian has changed to a pattern of inland storms for next week. If that were to happen, maybe the Southern Tier might then get some snow! Admittedly, more flip-flops are likely over the next few days. Jim G

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  4. The current storm is an inland-runner causing snow to rain. You cannot beat the Rubik's Cube effect of ways to miss snow once it sets up-regardless of the location, track, or intensity of the low.

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  5. Ooops, 12z Euro does have a coastal storm on Wednesday, further to the west than last night (which pretty much went out to sea). Some snow in NJ. But the Canadian high isn't in the prime spot. Obviously, this will all change over the next few days, one way or another. Jim G

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  6. Jim G - just curious are you a weather willy fan or skeptic? Can never tell from your comments. You seem more passive aggressive vs a supporter. Just curious if I'm reading your replies right.....

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  7. Mr. Larry -- I'm definitely a Willy fan. He really knows his Wx and constantly keeps his eye on the relevant incoming data, just like any commercial wx analyst. Thank goodness that he's not charging us for his insights, not yet anyway (I see that the New York Metro Weather site is now trying to "monetarize"; to get their review of next week's possible storm, you need to "register for premium content" -- in other words, PAY UP). I appreciate that Willy has an open-forum for comments, so I contribute my .02 now and then. Sometimes I disagree with him just a bit, or believe there are other facts to be considered, so I put that out there for consideration. And he's been very gracious about this -- he seems to be taking a First Amendment approach. Personally, I think that such an approach makes it more fun, and turns it into a learning experience. I know that most of us just want the best, most reliable weather forecast we can get, but some of us also want to get under the hood and see how those forecasts are being made. And maybe even get our hands dirty a little bit, say things like "hey Willy, did you consider that the EPO is going to stay neutral over the next 2 weeks . . . " It's kind of like ESPN, where former players and former coaches and call-in fans anticipate or second-guess most every move, along with every game decision made by every major sports team every week. So, maybe this is the ESPN-ization of analytical WX forecasting! Like any true sports fan, most of the time I'm a supporter, but occasionally I'm a skeptic. Right now, I think Willy is winning the game on the storm for next week -- his summary post this AM about it is on the money. He acknowledges that the forecasting models are still not in synch on this one, not lining up like they did 7 days before the "Jonas" storm (although they had lots of trouble getting the magnitude of that storm right). But there's still "jackpot" potential, so stay tuned. Thus, as of this AM, I'm in the WX bleachers cheering Willy on! But like any heavy-duty sports fan and ESPN listener, I'll be calling in at some point, wondering why you didn't do this or that in last night's game . . . Jim G

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    1. Cool. Thanks for the reply and insight. Good to know. Have been curious for awhile and decided to ask as I'm a direct person!

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  8. Hey Larry, no problem. Admittedly, I'm a Wx newbie, my thoughts aren't all that important. But I thought it would be cool if other Wx-heads who know the game like Willie does were to chime in too. I mean, for something as important as an NFL game, you don't just have one play-by-player and one color guy; you need the likes of Boomer, Cowher, Bradshaw, Howie, Stray, Dan M, Phil S, Troy (and hey, even Joe Buck!). So I thought it would be cool if you had a panel of true Wx heads going at it whenever you have something as important as a winter or summer storm, with respectful disagreements allowed, maybe even encouraged (so long as it stays professional and respectful -- we wouldn't want to turn Wx forecasting into the NHL !!). Jim G

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  9. PS, I know I've said way too much and most everyone is sick of me by now, but I feel the need to say one more thing that I think is really important. I've been a bit flip and light-hearted about the trials and tribulations of weather forecasting, by comparing it with professional sports. But I DO REALIZE THAT WEATHER IS SERIOUS BUSINESS. People's lives are at stake -- weather can kill people. It's not just entertainment. Anyone who would go before the public and say "here is what I think is going to happen with the weather in the upcoming days" is taking on a grave responsibility. It's not a fun sport, it's not a competition, it's a matter of GETTING IT RIGHT. People who read or hear what you say about the weather are going to be making decisions about their lives based on what you say; I myself make decisions on whether to drive to work or use mass transit based on safety and convenience factors, which depend heavily upon the weather. Hopefully in the internet age, most people know enough to consult multiple sources of forecasts and make their own well-informed conclusions. Nonetheless, everyone who dares to put forth a WX forecast has to remember that they may well be affecting many people's lives. As to Mr. Willy, I think that he is well aware of this and is definitely living up to these serious responsibilities. Jim G

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