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eduggs

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  1. eduggs
    I have been following intently, for years. I appreciate you enthusiasm a lot. I think your concept of "pattern" is on shaky ground. I also don't think the current state of LR forecasting allows you or anyone else to identify productive snow periods more than about 10 days in advance. I would respectfully encourage you and everyone else to follow Walt's lead and focus more of specific synoptic feature combinations in the mid-range and less of fleeting fantasy "patterns" out in fantasy land.
  2. eduggs
    I'll say it another way. The physical and psychological attributes that make a good basketball player are complex. If we relied only on simplistic metrics like height to predict basketball prowess, we would not be very successful basketball scouts. The forecasting of complex patterns requires very precise identification of causal factors and large practice-set sample sizes, both of which are currently lacking in LR weather forecasting.
  3. eduggs
    What you posted is not a "pattern." It's a graphical representation of a set of numerical values at the continental-scale. It's a purely static depiction. Any meaningful definition of weather "pattern" should incorporate the wave dynamics associated with evolution and propagation of airmasses. In that way, "pattern" and "cold" should always be interrelated. In fairness, everyone on this forum would be better off if we all stopped using the term "pattern" because it usually just leads to misunderstandings and unfulfilled expectations.
  4. eduggs
    IMO the coupled global atmosphere and ocean systems are way too complex for easily identifiable and repeatable patterns. Personally I think there are general recurrent features, but not as predicable as you suggest. "El Nino" is a numerical range used to represent a particular geophysical variable in a general region. No two El Nino seasons are even close to being the same.
  5. eduggs
    Are you suggesting that "cold" is independent from "pattern?" That doesn't make a lot of sense to me. You might as well just wait until "cold" and "moisture" are collocated at the same time and place before forecasting snow. A so called favorable "pattern" is never sufficient for snow around here.
  6. eduggs
    As you mention, certain key features are correlated to NYC snowfall, particularly if you isolate major snowstorms. So this is a situation where the features are necessary but not sufficient. That's part of the frustration with long range forecasting. Even if we see these features modeled, we usually don't get a snowstorm. The other major issue for the LR is that ensemble modeling is not stable or reliable enough beyond 10 days to make accurate regional forecasts.
  7. eduggs
    Ensembles have a transient relaxation of the western trof next weekend. 500mb anomaly charts look decent around that time too. Unfortunately the actual surface weather is likely to be rain to dry NW flow. That's the weakness of 500mb height anomaly charts. Favorable anomalies are only loosely correlated to local snowfall. Snow threat identification requires a closer examination of the full synoptic evolution, not just 500mb and not just a snapshot in time. 500mb anomaly charts are also better suited for identifying setups that won't deliver as opposed to ones that will.
  8. eduggs
    They also teach that there is near zero skill at the regional-scale beyond 10 days. Yet all I read on these forums is how good the 15 day ensembles look. I really thought after last year there would be some serious rethinking about super long range forecasting and lessons learned. But instead people keep doubling and tripling down on failed approaches. Does anybody bother to go back a few weeks or months to see what they wrote about the 15 day ensemble means back then? How did that turn out? There's so much wishing and hoping that it's hard to believe. Go back and look at what you posted almost every day all of last year. Seriously. Go check. Always a great pattern out just beyond the rainbow.
  9. eduggs
    I know it doesn't matter since it's 6 days out and it will change every run, but the UKIE was still snowing at the end of its 12z run.
  10. eduggs
    Unfortunately the modeled negative 500mb anomalies centered around December 11 are very transient. Seasonable cold is gone in a day or two and there are currently no obvious shortwaves to key on in that timeframe. Hopefully something trackable materializes, but right now there's nothing much encouraging on the horizon out at least 10-15 days.
  11. eduggs
    Yeah not a ton of cold air around this fall. But I want to reiterate my point that 2m temp. anomalies are misleading in terms of describing airmasses. The 2m temp maps that you posted yesterday gave a false impression of warm air when in fact the forecasted airmass was seasonably cold and theoretically supportive of wintry precip. for part of our region during that time period. Cloudy nights usually show up as strongly positive 2m temp. anomalies even with a fairly cold airmass because of the lack of nighttime thermal radiation relative to average.
  12. eduggs
    The 2m temp. anomalies are pretty misleading. They depict cloudiness and time of day more than anything. It's not frigid but there's plenty of cold air during that time period. And if you loop the NA 850mb temperatures, you can see the source region is eastern Canada. The anomalies look like they advect from the Pacific, but anomalies don't advect, heat does... through the movement of air.
  13. eduggs
    15 day 500mb anomaly charts are pure fantasy. Even if they weren't wildly inaccurate and we could take them for future reality, favorable anomalies don't necessarily mean snow. We need successive run, multi-model ensemble snow threats in the 7-10 range, at minimum, to justify excitement.
  14. eduggs
    H5 has really improved on the 0z ICON and CMC. Multi-run trend towards a strong, more consolidated mid-level low instead of a dampening open wave. PVA and cold pool continue to tick further south. Temps below 925mb level will always be a challenge this time of year. But H5 is finally starting to look like a legit interior snowstorm.
  15. eduggs
    The trend towards a higher impact coastal storm on Wed. continues with the 0z CMC. The cold pool aloft on that run now almost passes overhead. A quick glance at those charts in any winter month and you would think this was a snowstorm for NEPA, NNJ, SENY, CT. It's really only the surface to near 925mb that's a problem. Even the City would probably be upper 30s in steady precipitation. Highly trackable event after a long break from winter. Good 0z so far.
  16. eduggs
    The 0z ICON now has a legitimate far interior snowstorm for Wed - Wed night. Mixing to NW suburbs. Also a significant shift towards a storm on the 0z GFS. Most guidance has been ticking deeper, sharper, and further southwest with the approaching shortwave for the past several runs. Even if frozen precipitation stays far to our north, this is a very trackable winter storm. If the 0z ICON or even 12z/18z ECM is close to being correct, this could be a decent snowstorm for elevated spots in the Catskills and Taconics. And there's still time for this to continue evolving. The GFS still has further to come... the UKMET I think as well.
  17. eduggs
    0z GFS, CMC, and ICON at least all look potentially threatening for something wintry, particularly for the LHV and CT. Eminently trackable. Just hate when there's a mid-level low to our NW.
  18. eduggs
    The mid-level track and snowfall distribution for next week's modeled event look a lot like several storms we had earlier this year. Run to run consistency is good for central NE, but not as encouraging for us.
  19. eduggs
    Agreed. But let's not prematurely get carried away. It's still a so so threat. The mid and low level lows are still modeled to track through the central Great Lakes into southern Ontario. Historically that's a tough setup for the immediate NYC area. The antecedent airmass is also only modestly supportive of wintry precipitation along the coastal plain. But, I really like the trends towards really strong PVA and rapidly developing coastal SLP. I'd like to see the mid-level lows shift a little more southward. Still some work to do.
  20. eduggs
    The 0z UKMET gets the ULL pretty far north. Would probably be some decent deform snow NEPA - I-84 corridor. The soundings that I can see - GFS - are really warm above the deck. Wish I could see some of the others. I think you're right that localized banding would cool the column - probably deep layer isothermal result.
  21. eduggs
    If a model shows it, it can probably happen. I'm not optimistic either, but snow is still plausible. One good thing is the delayed progression of the now bowling ball modeled ULL allows colder surface air to filter in. In earlier modeled scenarios, the mid-levels cooled faster than the surface. Now we will be fighting the rapidly warming mid-levels instead.
  22. eduggs
    I don't like when the cold air source gets pinched off like most models are showing. And for the reason that you describe - the mid-levels get torched. That said, a good number of 18z GEFS and especially EPS members showed showed some snow for our area, so I don't agree that there is no hope for a Sun or even early Mon event.
  23. eduggs
    I think the delay trend went a bit too far. A touch of snow now in Louisiana and Mississippi on the GFS. Upper levels torch quickly after the mid-level center pinches off. I hope this reverses a bit, otherwise we're left with rain and ZR. Shame cause it could be kind of a fun, low expectation, parachute bomb event.
  24. eduggs
    Actually cold air does seep in after the initial Saturday impulse but is quickly displaced before the pinched off ULL can rotate in some precipitation on Sun or even early Mon.
  25. eduggs
    Maybe. I was just trying to point out the difference between atmospheric scientists, climatologists, hydrologists with graduate degrees, PhDs etc who do research vs. "weather forecasters" who tend not to utilize the scientific method as readily. Certainly there is overlap, but in a general sense there is a divide between the types who study meteorology in college vs. physics or chemistry.
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