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Everything posted by hm2

  1. In general, when making monthly calls, it has been easy for the Midwest-Northeast. Niño climo keeps the traditional look going through April. But, we have seen this winter, periods of short but impacting shots of cold/snow. There may be 1 last one ahead; and interestingly, a storm threat could time with the Easter Holiday. :/ But the changes that get us to that point are already underway, and a big player in seeing that this happens is the big N. Atlantic-Scand. High break next week.
  2. There is no denying the warmth through the next couple of weeks. The AAM propagation, the wave breaking next week (anticyclonic wave breaking in N Atlantic) and the extreme stratospheric -u wind (possibly doubling the old record from March 1999 at 10mb/60°N) to me suggests another -NAO developing. We have not seen our last East Coast storm and possibly a winter storm threat. Obviously in late March, you can't really stick your neck out in terms of snow...but the threat is there. Climo obviously says interior. Enjoy the spring fling.
  3. Virginia still seems like the big winner with this scenario. Now it's a matter of how much can we spread the wealth into NJ/PA.
  4. You happen to mention the ensemble mean southward shift and some deterministic shifts and all hell breaks loose (lol twitter). Anyway, these trends are not going to lead to some monumental bust in the Mid Atlantic. However, they are obviously important for PA-N NJ-New England.
  5. Only 15" in S NJ??!? Boooo.... In all seriousness, the GFS definitely was south initially, but it also doesn't seem to matter during the maturing/occluding stage. It is a bigger deal for anyone forecasting in the SE USA and has to deal with the CAD. Further adjustments are possible.
  6. I'm just bringing up the possibility that where the snow is wettest, it could also be where winds are stronger. It's 1 threat to look out for besides all of the other more well-known risks at this stage.
  7. The soundings across the interior are sick, yes. I'm not talking about these locations.
  8. The other possibility is that there are just fierce snow bands, convective in nature, and it's the in-between spots where soundings look iffy (remember I'm talking closest to rain/snow line). That would be a better scenario.
  9. It would be a lot easier on the area with the ECMWF solution honestly.
  10. Something closer to the ECMWF would be a lot easier to deal with region-wide both with the amounts and style of snow. Something like the GFS would be a headache.
  11. The tucked-in solutions could get ugly really fast in portions of DE-NJ that stay as snow. If you examine the 6z GFS soundings in the areas just NW of the 925mb 0C line, there is not good dendrite making and the temps are warm at the ground. it looks like a heavy wet snow pasting with strong wind. Yikes.
  12. Good point about precip type. When I see the kind of winds being modeled right now aloft, I can't help but to think grainy or snow pellets etc. with warm advection.
  13. Yeah, I think it's likely we see accumulating snow. I'm just trying to figure out, as stupid as that may be at the moment, where the bigger snows will land should the trends continue.
  14. But are these NW members just being flung around during the occluding process? Where are they relative to the mid level low? The NW clustering we keep seeing may be the models showing them coming NW before going vertically stacked. What a pain this is!
  15. I could see this just dumping furiously in the Mid Atlantic, esp. VA, and sending out 1 really good frontogen band at us before everything begins to weaken...should this slower trend continue.
  16. But are they getting snowier because of that trend or is it because they are just shaking off more erroneous solutions, e.g. out to sea?
  17. The SLP will get thrown around this during the occluding process. The slower this goes, the better the chance for big snows to set up south/west of us.
  18. Just compared the mean 500mb heights between the 00z run and the 12z run for same time stamps and you'll see what I mean. It's more of a slower trend than it is southward.
  19. The EPS has trended a full 6 hours slower and more south as well from the 00z run.
  20. In fact, I encourage you guys to do a 6z to 12z to 18z comparison of mean 500mb heights/slp. All day it's been coming west and going slower.
  21. Another great example of how spread can help anticipate trends. Notice the 18z GEFS is slower and again west.
  22. It's not so much as amplify the long wave as much as it's about how quickly the thing matures/occludes and becomes vertically stacked. If this process is slower to occur, we will likely get raked with 1-2 FT of snow region-wide. If it happens extremely fast and intense, it could pull in a lot of warm air and just dump on the higher elevations west of the big cities.
  23. All ensemble mean trends today have deeper midweek s/w that acts as 50-50 low and are slightly weaker with arriving Pacific waves. This gives the main wave enough room to amplify...and then some.