weatherwiz

I woke up to a coating (if you could call it that) of snow...was pouring like crazy though so perhaps had more than a coating before we flipped to rain. Driving on the highway basically into Wallingford was a disaster...I don't understand this state...highway completely dark with no lights. Very scary to drive in these conditions.

We are down to 79-days to go!!! Once the 0z GFS completes tonight..it will be into March (well technically still Feb 29 but 0z March 1st!!!) which means there would only be ONE full month left in the model world before May

Approaching mid-February! Is that pattern change still coming? Getting closer and closer to spring

I have that same problem. I've sort of gotten away from it though...moreso just b/c of time. but I liked doing it in hopes of teaching those who are interested in learning more...or sparking them to gain an interest. I think the reason why I've done it is b/c when I was trying to learn I killed for in-depth discussions...I wasn't looking to be told the answers...but be presented with enough of a basic background to pave the path for me to explore more.

There is growing consensus in the medium range for a long-duration winter weather event to impact at least a portion of New England. A rather significant trough is expected to dig into the western U.S. over the weekend and continue to amplify as it progresses through the central states. The response will be a strong ridge in the east. There are uncertainties, however, regarding the structure of the ridge across the Northeast as there are indications this will flatten out some. This is key as the trough and associated cold front approach the stage may be set for a long-duration overrunning event across New England; including the potential for a significant icing event.

Fine...this one too long anyways. I have good luck with the severe threads. give me a minute

yeah Wednesday into Thursday.

Verbatim looks like we get some ice...with the worse up in the Litchfield Hills (in terms of CT) with a significant ice event eastern NY into central New England

I'm down for some significant icing and power outages

It's only 6-hour totals but they are quite hefty across New England for ice. that would be a pretty big disaster

I don't want to muck up the Feb thread anymore but going back to what Scott was saying earlier about the warming oceans this is pretty insane. Small sample size being used of course but here's a list of the three previous weak EL Nino's and three weak EL Nino's from the 1970's Here is moderate One thing to keep in mind though is not taking into account the phase of the PDO/AMO. IIRC the AMO was negative in the 1970's as was the PDO. AMO has been positive since the mid 1990's.

I wonder if this is the type of storm that can really change the pattern...how this storm evolves as it moves northeast looks like it could really buckle things and we can get pretty chilly behind it.

This reminds me...remember that whole ridiculous idea the a KU storm couldn't occur during a La Nina (think it was La Nina)...and then it finally happened I remember we had a few discussions about this either at a conference or a g2g Anyways though...I don't disagree with you at all...plus it's all about presentation and backing up your analysis...which you do just about as good as anyone.

Disagree...there are certain patterns in which the models have a difficult time handling. It's even been mentioned in forecast discussions before when something like this is the case. The more pieces which are introduced into the forecast the more complex the result becomes and the higher the likelihood for inconsistencies and drastic changes. I remember this pretty well surprisingly. That was a shock beyond belief.

I don't think there is anything wrong with it at all...hell...I would probably do the same with tornadoes if I did summer outlooks...but I know that's not really a great measure b/c you don't know how any specific event will pan out. My point is there are so many factors which influence snowfall (or tornadoes)...which can't really be predicted off any indicator. It takes just one storm which can completely put at risk a season forecast. Say you go with something like 30-40'' of snow...but one storm drops 18''...nearly half your forecast just fell in one storm. Or you forecast like 500-700 tornadoes for the spring/summer but there is a massive outbreak in early April that spans 300 tornadoes. I wasn't saying it isn't a worthwhile endeavor...its there is way more (especially short-term and mesoscale aspects) which are involved in these outcomes than a projected pattern itself.

One thing to watch too is the HP north of ME. That could play a significant factor in the height field across New England. This could at least really benefit NNE

second this. Some out there are way too attached to their thoughts and become overly aggressive when disputed.

This is a significant part of it. Alot of the correlations made and understanding of how each phases influences what type of pattern...it's all really derived from understanding of how those indices influence the pattern when their signal is strong...so when they are either highly positive or highly negative. When there are certain indices that are overly strong and dominant...LR becomes much easier...however, when signals are weak the correlations to the pattern decrease significantly. A huge example is the NAO...we think of the NAO (or AO) has a major driver to cold here in the Northeast...and that's true...but when the signal is strong and dominant. When the NAO signal is weak...a negative NAO can still be associated with warmer temperatures in the Northeast. It's not as simple as -NAO/+PNA = cold.

After Scott's response it occurred to me that perhaps this index doesn't have the value it once did when it was created? Though I thought it was created after the ONI? but all these measures of ENSO...just may not be applicable anymore...at least enough to compare periods. The new climo period is when...next year? It is going to be extremely intriguing to see how numbers and average change...and by how much. I suspect we may see some drastic changes which should and hopefully raise major eyebrows.

That's a great point about the long-range industry and the future. The long-range seasonal models are good...and good enough to provide value to those that need it. But like you said...there may still be value from mets. Heck...Will's example above even sorta shows that. In this time of warming you can sort of see which areas perhaps may be more prone to colder weather as opposed to warmer weather...perhaps models won't pick up on that but if that's something human value can add there will still be somewhat of a demand.

I see two aspects to long-range forecasting. 1) I could be completely wrong here but I think one of the big drivers and demands for long-range forecasting is the energy industry. 2) Long-range forecasting driven by "weenies" who just want to know how much snow they'll get the upcoming winter. While there are some excellent attempts at long-range forecasts that is available for anyone to see (for example Ray and isotherm (Tom) come to mind) most of what is available or what people do is just completely driven by the desire to want to forecast for cold and snow. I would be willing to wager that long-range forecasts presented to energy companies are a completely different tune...and probably way more accurate then what you would find floating on twitter...and that's b/c of what is driven to construct the outlook.

I think overall long-range forecasts are decent...heck even good. There are some out there who are phenomenal and just have an understanding of the atmosphere like nobody else (Anthony Maisello for example). but part of the issue I think is some try to incorporate too much detail into seasonal outlooks...one of them being forecast snowfall totals. I think this not only vastly reduces accuracy of some seasonal outlooks but sort of takes away from the outlook itself and the work that goes into it. Forecasting snowfall...and precipitation for that matter is exceptionally difficult in the long-range. You can perhaps wager possibilities given what you expect the pattern to be but there is no guarantees the patterns produce. IMO, precipitation is more correlated to "blips" in the pattern than the actual pattern itself. Another one is temperatures...some try to use a range...like Feb will be +2 to +4. I think it would be better to just be as simple as below-average, around average, or above-average...and then spicing that up however.

I actually totally and completely agree with this. Its like the data set and correlations have to start all over again...from more recent times. This is also why I don't like how many of these reanalysis sites (for example the monthly composite page from the ESRL) only has the most recent climo period...how can you really compare something from like 1924 to the base period of 1981-2010? The entire climate background state is completely different.

I share the same thoughts. Perhaps it's just related to just how complex the pattern is with so much moving pieces. There are other issues which I hypothesize as well (mentioned them a few times over the past few weeks) but with pretty much zero background in model development and how all that works...my hypotheses has little merit.

Are you very familiar with the Trans-Nino Index? There is something about interpreting it that I am confused with. Per my understanding, the TNI is a measure of SST gradient between the eastern portion of the equatorial Tropical Pacific (Nino Region 1.2) and central portion of the equatorial Tropical Pacific (Nino region 4). When the TNI is positive that indicates the SST's are colder than average in the central portion of the tropical Pacific and warmer than average east of that (though not sure how that can be the case during an EL Nino event). anyways...to try and further understand this concept I just looked at some weak EL Nino winter's and took the average of the DJF TNI values...and plotted SSTA's for a few of the positive TNI's and negative TNI's: My take from this (at least for weak EL Nino events) is a negative TNI during a weak EL nino indicates warmest anomalies closer to the dateline whereas a positive TNI has the warmest anomalies off the coast of South America M<y point from all of this really is to dig more into looking at ENSO events beyond just strength but whether they're east/west/central based...though how the evolution transpires is probably even more important.