Jump to content

Holston_River_Rambler

Members
 View Profile  See their activity

  • Posts

    5,107

  • Joined

  • Last visited

 Content Type 

Everything posted by Holston_River_Rambler

  1. Holston_River_Rambler
    EPS member 25 is love! well, if you live in the pink area lol
  2. Holston_River_Rambler
    Def. a nice cold feed oozing down from the arctic:
  3. Holston_River_Rambler
    Euro took some steps toward the OP GFS at 12z, IMO.
  4. Holston_River_Rambler
    Just from reading the intro to the paper Furtado cited, it seems to me this "wave reflection" activity is something we're still struggling with: https://journals.ametsoc.org/configurable/content/journals$002fmwre$002f148$002f4$002fmwr-d-19-0339.1.xml?t:ac=journals%24002fmwre%24002f148%24002f4%24002fmwr-d-19-0339.1.xml Here is a key paragraph IMO: "Second, the polar vortex can also act as a reflective surface, preventing the absorption of upward-propagating waves. Troposphere induced waves entering the stratosphere are then reflected downward, thereby influencing tropospheric circulation (Harnik 2009; Shaw et al. 2010; Perlwitz and Harnik 2004; Kodera et al. 2008, 2013). While the occurrence of wave reflection is well documented (Perlwitz and Harnik 2003; Shaw et al. 2010; Nath et al. 2014), its impacts on surface weather have been given less attention. Recently, Kretschmer et al. (2018a) showed that downward reflected waves over Canada favor North Pacific blocking, respectively, a negative phase of the Western Pacific Oscillation (WPO), and are associated with cold spells over Canada and the northeastern United States, consistent with earlier case studies (Kodera et al. 2008, 2013). Nevertheless, the exact role of wave reflection for North American cold spells, as well as the possibilities for subseasonal to seasonal (S2S) forecasting has not yet been comprehensively assessed."
  5. Holston_River_Rambler
    Here's a thought. Strat stuff seems to give models problems. I think we can all agree on that. How do models visualize things like the wave reflection Furtado is describing? Is it just a storm driving poleward carrying heat that hits a stout SPV and gets shunted back down (in altitude and latitude) in the flow? What hPa level does that happen at? We normally look at H5 vort maps for storms, surface reflections, or the jet stream and 200 or 300mb to see a storm and we have all those atmospheric levels on all the models we look at so its pretty easy to see a storm forming, breaking, and eventually dissipating. Does it really disappear though? Does the energy flux up to like 100mb, 50 mb, and eventually 10mb and take heat from the mid latitudes with it? It just seems to me that there is this nether region of modeling (at least as I usually use them) above the jet levels and I have no clue how or if that gets modeled. We always look at models as 2D projections, but really those higher and lower heights are just that, bowls and hills in the atmosphere creating baroclinic zones. I wish there was some way to tilt the projection and get a 3rd dimension on a planetary scale, something besides a sounding or even one of those cool cross section soundings. I think I kind of answered my own question toward the end of that, but I guess what I'm getting at is this. As waves get "reflected" (whatever that actually means) could that cause some blind spots for modeling?
  6. Holston_River_Rambler
    Excellent! I was actually interested to see some of the indvidual members after the OP day 10 look.
  7. Holston_River_Rambler
    Allow me. 2019:
  8. Holston_River_Rambler
    I think it is definitely decelerating and weakening and looks to weaken quite a bit more: I guess though instead of splitting it as waves break, those waves that bring the warming are being reflected back down across the north pole into Canada. I really wish there was some 3D way to visualize not just the SPV but how a wave would attack the SPV and then be shunted back down to drive the pattern over N America.
  9. Holston_River_Rambler
    I think Polarwx is his personal website.
  10. Holston_River_Rambler
    Euro's EPO would surely dislodge some cold south: Twould be interesting to see how far SE the shallow cold could make it:
  11. Holston_River_Rambler
    The above was from earlier in the winter. Here is a current graph for the same wave reflection phenomenon: so even though the waves aren’t destroying the SPV they could still be meaningfully reflected toward Canada if I’m reading that correctly and cause swings in modeling wrt the cold
  12. Holston_River_Rambler
    I’m kind of wondering if the reason we’re seeing the cold push in early February has to do with the waves being reflected as they attack the SPV and heading due south out of the North Pole through Canada. Apparently that is a thing that can happen:
  13. Holston_River_Rambler
    That run ended up with some 12+ inch lollipops of qpf over the Frozen Head mts.
  14. Holston_River_Rambler
    After the GFS's lascivious indulgence yesterday at 12z, the sinner repents and gives us our favorite February pattern! I know it is only one run, but if the trough dumps out west and fights the SE ridge, we may end up on the boundary. That is a very realistic and possible progression.
  15. Holston_River_Rambler
  16. Holston_River_Rambler
    Always remember Dale from this date in 2016:
  17. Holston_River_Rambler
    Disclaimer: the following has noting to do with the next couple of weeks. With regards to the strat stuff, EasternLI had a good post in the NY subforum this AM: You can actually see what EasternLI is talking about on the 3D maps: The top of the vortex definitely gets smaller and slows some, but the bottom seems to keep chugging along. I don't necessarily think that this means a huge change for better or worse though. 1. Even if we had a major top down SSWE, it would take until the end of Feb at this point to see real impacts in the Eastern US IMO. So we were still looking at a couple weeks of an unfavorable pattern in mid Feb. 2. A weakened SPV shouldn't impact the meta-pattern we've been in since fall, the 2.5 weeks of unfavorable pattern, then a week to a week and a half of better chances. I'd almost go so far as to say that when the pattern shifts again at the end of Feb. we will have better chances than with the one we're in or heading for now over thee next week and a half or so. Remember October? The cold snap we got for a week that month was stout. The one at the end of November, ehh, not so much. December? We all remember that one. Hopefully everyone has their water back by now. The one this month? Certainly the GFS has hinted that a major cold snap is possible, but. I suspect it will be more muted like that of November. As the wavelengths shorten and as the MJO makes it slow pass back towards the more favorable phases toward the end of February, I'm really interested to see what we end up with by Feb 25th or so.
  18. Holston_River_Rambler
    Happy hour GFS sobered up, but at least it has a nice cross polar flow in the long range.
  19. Holston_River_Rambler
    I'll probably eat this at 18z, but the past couple of iterations of the GFS seem to do well at guestimating timing for big HPs dropping down the lee of the Rockies. It's OP runs have had them pretty consistently for a few cycles now. I think some cold is def. dropping down, just have to hope it makes it east.
  20. Holston_River_Rambler
    It’s Saturday so happy hour started at noon. Half price well drinks until 18z!
  21. Holston_River_Rambler
    If it rains before seven, it'll stop before eleven.
  22. Holston_River_Rambler
    Beautiful surface track on the 22-23 storm: If only we had that track in January and there was some cold air around lol. <sarcasm intended>
  23. Holston_River_Rambler
    We should have a year where instead of models, we just run through weird old mountain folklore.
  24. Holston_River_Rambler
    Pretty similar at the surface to some of the looks at range we had for the December PV visit: December GFS happy hour run at range Current happy hour GFS run at range:
  25. Holston_River_Rambler
    Nice happy hour GFS run for the ever popular day 10 window.
×
×
  • Create New...