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Showing most liked content since 11/15/2017 in all areas

  1. 17 points
  2. 13 points
    So times are a changing. We currently right now have a very zonal flow (flow is west to east) You can see that from this map. When the flow is zonal like this it is very easy to see why we aren't cold. The air is coming straight from the Pacific. Note, that even though we do have a -nao signature, it's displaced to far north and also the air in Canada, while cold is of Pacific origin. Also note, do to the zonal flow, all the cold air is bottled up north of the border. You need amplification in the pattern or a further south -nao to force the cold south. This zonal flow is also connected well with phase 4 MJO which shows a very flat flow/ridging. (Above) current green anomalies showing the tropical forcing pushing out of the IO region and towards Indonesia This zonal flow though will not last and we can trace the pattern shift back to Asia with a strong closed low that I have marked X. Note the looping feature, the wave break from this disturbance gets the ball rolling in the Pacific with pumping a ridge out ahead of it. The ridging caused from the wavebreak becomes a very stable feature as each each low on the wave train in the pacific only reinforces it. As we get further down the road in the 10-15 day period, the MJO also starts supporting a west coast ridge/east coast trough. While the robust convection currently wanes, the area of forcing still continues to move towards the dateline and then the maritime continent and Africa. The tropical forcing of phases 7->2 take the rest of Dec and into early Jan for it to run it's course. So that is also supporting a persistent trough signal in the east for the rest of DEC into the first week of January. Now a result of a wavebreak in Asia pumping up the heights into Alaska and the West Coast and then later on the MJO signal backing that up, we get this look. This is what we call meridonal flow. Basically flow that is more north to south representing an amplified pattern. Unlike the zonal flow you can clearly see where the air is coming straight from. The amplitude allows for the cold air to come south. This would set up below normal temperatures and would increase snow/ice chances. Below is the day 10 ensemble forecast off the EPS. This h5 map is basically the holy grail for any fan of cold and wintry weather. You have a +pna to give you the amplitude in the pattern to allow shortwaves to strengthen and to send the cold air south. The -nao slows the pattern in the Atlantic down blocking in areas of low pressure and high pressure. You also have a -AO which displaces cold anomalies that are usually found at the pole south into the mid latitudes. This is another source for bringing cold air south. Furthermore, due to the h5 configuration of an Aleutian low and Siberian high, this is a classic wave 1 disruption in the Stratosphere which we can see below. Wave 1 hits on the Stratospheric polar vortex are a good signal that cold air is on the move south. With that being said, the MJO forcing progression into cold phases and the continued hits on the Stratospheric PV Colder than normal December is gaining some ground. If these Ensemble outputs are correct snow chances are going to go up.
  3. 12 points
    3:00 pm Snow 29 degrees 2.9" Bumble is living large today
  4. 12 points
  5. 11 points
  6. 11 points
    3.75" on top of my van... still sitting at 31 I was pretty mopey this morning looking at overcast skies, but this really puts me in the seasonal mood.
  7. 11 points
  8. 9 points
    Definitely over performed here in the Lehigh Valley. Nice day. Now for a nice evening!
  9. 9 points
  10. 9 points
  11. 8 points
  12. 8 points
  13. 8 points
  14. 8 points
  15. 8 points
    My WAG on snowfall. Think temps will be 1-2 degrees above normal
  16. 8 points
    From our table at NWS Mount Holly to yours, we wish you a happy Thanksgiving!
  17. 7 points
  18. 7 points
  19. 6 points
  20. 6 points
    West Caln Township: 6pm 3.6” Pics from East Fallowfield earlier
  21. 6 points
  22. 6 points
  23. 6 points
    Army-Navy at the Linc this afternoon at 3 pm, few things in sports are as great as watching a football game played in the snow.
  24. 6 points
    This is slightly OT, but screw it. Don't you guys love this? Let's face it. Some of us are pro meteorologists, some are just casual people who are here for a simple wx report, and some are hobby-ist, oh and some are hobby-ist who dropped out of met. school (like myself lol)....Anyway, regardless of your passion, this is what it is all about. This storm won't make any record books or anything, but I absolutely adore events like this where each run ticks better and better, then maybe ticks down here and there, and then we have the usual surprises during the event. Anyways, we await the KING should be running just about any minute.
  25. 6 points
    I'm fully expecting the euro to do this to us
  26. 6 points
    Same low as Tom up in Bangor, PA, and same result.
  27. 6 points
    Had these up for several days but finally got around to a picture
  28. 6 points
    Philly total snowfall by decade, just be glad you're not a weenie growing up in the 1950's - 30" during the month of FEB
  29. 6 points
  30. 6 points
    I love the long days of summer for being outside on the deck and having a late dinner... But for the winter "indoors season," when in the "cozy-up by the fire" mode, the early darkness adds to the feeling... There's something nice about winding down early on a Sunday evening because the day is already over... And when I am still at my desk at 7pm on a weeknight, I feel less like I am pissing my life away if it's dark already anyway [emoji57] Sent from my iPad using Tapatalk
  31. 5 points
    Below are the top 10 December snowstorms (for 2 day storms - last day listed) for Chester County PA (Period 1894 to Present) 1) 12/26/1909 - 38.0" (see the handwritten obs attached - snowing furiously on Christmas Day and very deep snow on the 26th....ya think?) 2) 12/24/1966 - 21.2" 3) 12/19/2009 - 15.0" 4) 12/14/1917 - 13.5" 5) 12/6/2003 - 12.5" 6) 12/4/1957 - 12.0" 7) 12/6/1910 - 10.7" 8) 12/24/1912 - 10.3" 9) 12/20/1966 - 9.6" 10) 12/11/1960 - 9.0"
  32. 5 points
    This is about as active as it can get leading into Christmas. 1. Wednesday snow showers 2. Thursday clipper 3. Friday/Saturday coastal/clipper 4. Early next week overrunning ( say 18th ish) 5. Post frontal overrunning waves of low pressure ( a few days before Christmas)
  33. 5 points
    The 12/9 collection, most already posted in obs thread
  34. 5 points
    Shady Brook Xmas Light Show Smores taste better when snow falls on them while your eating....
  35. 5 points
    Courtyard of our apartment complex in Sinking Spring, PA.
  36. 5 points
  37. 5 points
  38. 5 points
    Just quickly drew this up. But imo ideal around Detroit. Center line is your trough axis. You want to be to the right of it. Shortwaves then can amplify at the base of the trough and track northeast. You can see on the right you get a little se ridge look. You don't want to be to far right than it's cutter look. If you're left of it, shortwaves can't amplify till they're past you, more of a clipper pattern.
  39. 5 points
    You need this ornament on your tree.
  40. 5 points
    Happy belated thanksgiving all. Round 2 today in the city after round 1 up in NY Thursday. Beautiful day today.
  41. 5 points
  42. 5 points
    Fall run for striped bass just getting started. Fished seaside heights/Ortley beach the other day. Plenty of adult bunker around, just no fish close to shore. The whale(s) put on quite a show close to the beach.
  43. 4 points
    2018 thread gets a head start... A few others from 12/9
  44. 4 points
    My fan is ready to give it the extra nudge, look at those streamlines!
  45. 4 points
    Low end looking good. This event gets bonus points for: Saturday, daytime, cold temps, and pre-xmas.
  46. 4 points
    Waiting at daughter's choir practice in Haddonfield. Christmas songs being sung in background while watching snow fall from a nicely decorated room. Winning! Lol By coincidence had to drive through the worst of the Eagles Snow Bowl too (ballet practice that time lol)
  47. 4 points
    move this post to banter if needed, but, today (edit: yesterday) is the 4-year anniversary of this at the Linc, which I was lucky enough to witness:
  48. 4 points
    For those who do not know ERH is eastern region headquarters out on Long Island. Basically a support center for all the wfo's on the east coast.
  49. 4 points
  50. 4 points
    To the nearest minute the sunset today matches the sunset on Christmas Day making Thanksgiving as usual the darkest holiday of the season.
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