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Showing content with the highest reputation since 10/08/2018 in all areas

  1. 16 points
    What’s up guys (and gals)? It’s been a little while since I did some analysis on the possible state of this winter, so I decided that since fresh September index values were calculated by NOAA, it would be a good idea to make some rather preliminary forecasts. These are composite-based, as are most of my long-range forecasts, and they are formulated based on this past September’s observed PNA, NAO and AO values. I will be doing these subsequently for October and November with (hopefully) increasing accuracy as we move into December. This September finished with PNA=+1.44, AO=+0.585 and NAO=+1.67. Since positive values were observed for all three major indices, I made a composite of all winters that had their preceding Septembers feature a +AO, +NAO, +PNA trio. That composite looks like this for December-February: One look at this composite and you’ll immediately see a very strong -ENSO signature: a powerful Aleutian ridge and a strongly -PNA with a very cold W US. This made me eliminate the -ENSO winters, as we have a very high chance of experiencing a +ENSO for the upcoming winter. The ENSO has a major impact on a winter’s background forcing, so including -ENSO winters in this composite is almost useless. The vast majority of the years in this composite were -ENSO, and once i finished revising, only 2014-15, 2009-10, and 1997-98 remained. The new composite looked much more +ENSO-esque: The strong Aleutian Low and defined STJ are very common +ENSO characteristics. The super Niño of 1997-98 was included in this composite, so the strength of the Aleutian Low will most likely be less overpowering this winter. I highly doubt we will have too many issues regarding a ENSO driven PAC flow like we would see in this composite. The trough would most likely be focused near the Aleutian Islands rather off the WC. However, I do agree with the blocking shown in the high latitudes, and the incredible 2009-10 winter is definitely an analog for the upcoming winter. The solar minimum that we have entered also bolsters the case for strong polar blocking. Above are the temperature and precipitation departures from normal for the 2014-15, 2009-10, and 1997-98 winters. I agree with the distributions of both sets of anomalies. The temperature anomalies will most likely be colder in general due to the extreme heat of the 1997-98 winter skewing the mean slightly. However, the idea of a warm WC/S Canada makes given sense given the +ENSO background conditions. California and the SE coast/EC look to be much wetter than normal, which is indicative of a defined STJ. Both of these signals point towards a highly active winter along the EC with multiple coastal threats. The high latitude blocking along with a pumped up STJ is a recipe for nor’easters, but as with many +ENSO winters, cold air will might be scarce at times if PAC flow creeps in due to a slight SE displacement of the Aleutian LP. Overall, I remain highly optimistic about this winter due to the analogs that have been deduced from observed conditions along with a possible Modoki +ENSO event and the entrance into a solar minimum. The EC will likely experience an active winter driven by a +ENSO-driven STJ and polar blocking. Cold air might be scarce at times, but injections of polar air are certainly possible if a -EPO forms due to feedback from an Aleutian LP. Coastal storms (both on and off the coast) will probably be the most frequent storm tracks, and a few significant storms are likely. Once October comes to an end, I will revisit my analogs and remake my forecast if needed. For right now, however, I am very optimistic about the state of the upcoming winter.
  2. 11 points
    Great work in here gentlemen, @Armando S and @brooklynwx99. In general alignment with much of what has already been discussed, and while attempting to not reveal too much about the winter forecast thus far, I have reached very similar conclusions. The analog set this year is a bit fickle as there is only a small subset of years that fit the general conditions. Going back further to the 36 month time frame, the analog set thins even further - which is somewhat expected, but still, the subset is quite small. Anyway, confidence continues to rise in the overall progression of major hemispheric features. Oddly enough, the biggest uncertainty in my mind currently lies in the front half of the winter, as opposed to the more typical back half. I am still quite unsure as to how December and perhaps even the first half of January will play out. Analogs are split on this general time frame while almost all of them go into an extremely favorable synoptic pattern for cold and snow after mid January. The majority of our weighted analog sets currently match the projected back half of October pattern well - with a GOA low developing and ridging developing into BC and perhaps even a Western USA split flow. As this wave guide adjusts, the potential exists for another SE ridge episode in November. But the overall analog set leads to a very similar theme to what we have seen pictured above. I will include it here with the important note that these analogs, although weighted, are likely to change still as we get closer to the winter forecast release. PS - we weighted these analogs based off a variety of things (QBO, past 12 months of stratospheric evolution, NAO, ENSO transitions over the past 24 months, etc) A couple of things to take away that many others have mentioned above - A highly amplified higher latitude pattern continues to appear in most of the analog subsets - The potential for notable/significant high latitude blocking in Central Canada - A persistent and/or notable Aleutian trough - Insufficient/non-committal NAO suggestions on analogs, at least in the Atlantic domain While we continue to dive deeper into the analog portion of the forecast, my thoughts have not changed much for quite some time. I continue to believe that this winter has the potential to deliver periods of significant snow and cold, but the intensity and breadth of such episodes remains highly uncertain.
  3. 10 points
    Excellent work and research @brooklynwx99! I find this rather remarkable that some of my analogs I've plugged in solely using QBO progression is congruous with your composite. For instance, my composite has six analogs that resemble closest in the CPC's dataset dating back to 1948. Of the six, four were El nino years, one was more neutral (modoki-esque like). and one was more of a weak -ENSO. Again, this is assuming the gradual and steady transition of a eQBO towards wQBO from 30mb down to 45-50mb by Feb. Intriguing to say the least, with a high wavenumber rossby wave configuration, and key HLB ridges (notice the ridge over Europe, south of Scandanvia.. typically has implications for catalyzing upwelling momentum towards the stratosphere). Still a good amount to unravel given ENSO and other hemisphere forcing, but you can't not like where we're heading going forward.
  4. 9 points
    Geoff, just wanted to respond to this now -- thank you very much for those kind words -- my silence isn't necessarily an assent or dissent to some of the ideas posted by others in this thread; haven't had time to examine everything more closely in awhile, but I will offer my thoughts here when I do!
  5. 9 points
    Oh my gosh. Video from inside the eye. Looks like a summer day.
  6. 9 points
    I can see the NHC doing a post investigation and increasing this to a Cat 5 officially
  7. 9 points
    As discussed yesterday it was fairly obvious that there was a window for this type of strengthening to occur amid favorable synoptic conditions. Unfortunately it appears that it is happening. A nightmare.
  8. 8 points
    That's our @NSFW Weather Guy. Telling it like it is, so we don't have to. I'm typically extremely against laying into other forecasters in the community, but cranky literally could be responsible for deaths today. Hope that weighs nicely on his conscience.
  9. 8 points
    917.6 last pass. It was still strengthening!!
  10. 8 points
    I say cat 5 landfall, absolutely no sign of EW degradation, 5 mesovorticies, warm pool just off coast, mow low sheer...she’s gonna get stronger
  11. 8 points
    Lol at cranky saying 80-90mph winds with a 944mb strong cat 3.
  12. 8 points
    Terribly odd for a borderline, Cat 1 blob.
  13. 8 points
    -89C tops exploding around the eye
  14. 8 points
    Oh wow, SFMR winds of 75 knots and pressures down to 967mb
  15. 7 points
    I can see how this system tracks further northwest than currently progged by some guidance (EURO/NAM/etc.) taking it southeast of the Delmarva. With a rapidly developing tropical cyclone so close by to an already amplified eastern U.S. ridge, anomalously warm SSTs in the western Atlantic, and general Northern Hemispheric synoptic pattern that supports a strong eastern U.S. ridge bolstered by the MJO Phase 1, this should allow the remnant circulation of Michael to trend further northwestward in future model runs in my opinion, such that it passes either over or very nearby our region in the end. The role of the cyclone should be further aid in enhancing the eastern ridge via its intense diabatic outflow and feedback effects positively interacting with the other factors outlined above. Just my two cents lol
  16. 7 points
    Those in the Mid Atlantic and the Northeast may also want to watch this storm as well HMON and HWRF both show significant impacts for those areas
  17. 6 points
    Guys, F Cranky his call name says it all, we are better here than he could ever be. Let's stop this or move it to Banter please, not my board but lest not distract tis great thread and board with this hack. i de followed him last year with the blizzard when 18 hours out he was poo pooing this storm for NYC Metro. Garzi Mille Mugs
  18. 6 points
  19. 6 points
  20. 6 points
    ‘Anyone that’s followed me on twitter for a while now, knows my beef with cranky stands firm in his opinions refuses to fine tune, or change a forecast despite new data blames everyone but himself goes on a 3 day rant after being wrong, about how everyone’s dumb and he’s so smart you cant forecast every storm using google and wind direction maps lol
  21. 6 points
  22. 6 points
    Latest dropsonde says 80-90MPH storm. 80-90 miles from the center of circulation.
  23. 6 points
    Definitely a west trend in the models today with Michael for impacts up here
  24. 6 points
    Michael has shown many synoptic signs of strengthening over the past 12 hours. There seems to be some signs of rapid intensification hangover, because the community in general is not necessarily as concerned - or does not appear to be as concerned - and my theory is that the lack of explosive/rapid intensification with the storm has something to do with it. Nevertheless, the intensification will occur. Earlier today, Michael displayed continued hot tower development within a ring of convection along its southeast eyewall quadrant. The system itself remains asymmetric as westerly shear in the mid levels of the atmosphere continues to have at least some sort of affect on the storms broader circulation. However, about 2 hours ago, a large majority of the deeper convection and colder cloud tops became slanted upshear towards the northwest side of the storms circulation. This is another sign of gradual intensification. We are seeing the fruits of this now as convection has wrapped around the center of the storm. My suspicion is that the storms intensification will continue to be gradual, but if there is going to be a time when the intensification is most steady, it will be this evening. The latest microwave passes have shown a gradual but continued organization of the storms core, and most near term forecast models suggest that westerly wind shear will weaken a bit as the storm continues to move into a slightly more favorable synoptic environment. My hunch is that this will be a Category 3 by later today and perhaps flirting with a Category 4 not long thereafter.
  25. 6 points
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