Jump to content
  • Member Statistics

    17,587
    Total Members
    7,904
    Most Online
    LopezElliana
    Newest Member
    LopezElliana
    Joined

The Psuhoffman Storm


Ji

Recommended Posts

  • Replies 6.9k
  • Created
  • Last Reply

will be fun to watch this slip away over the next few runs... ;)

It will be but the euro has been too jazzing with digging things too far south and west at times this year so even though the gfs is out on its own and looks a little funny, I'm not ready to completely toss it even though I think the snow to rain idea is still probably the more likely scenario. Hopefully, I'm wrong and the increased blocking that's showing up on the gfs is real.

Link to comment
Share on other sites

Thats some pretty big evolution differences between the 18Z NAM and 18Z GFS after 60.

and I don't like the GFS one bit... it's creeping the 500mb energy north

don't scare people, it didnt creep anything, H5 still passes through southern VA on this run. The 18z GFS is a carbon copy of the 12z only weaker, so naturally the SLP is a bit east also. At H5 the differences are very minor. The real differences are between the evolution of the system on the GFS and to some extent the NAM versus the Euro/UKMET/GGEM. A blend between the 2 camps actually might work out pretty well for us, and that could be a good thing.

Link to comment
Share on other sites

don't scare people, it didnt creep anything, H5 still passes through southern VA on this run. The 18z GFS is a carbon copy of the 12z only weaker, so naturally the SLP is a bit east also. At H5 the differences are very minor. The real differences are between the evolution of the system on the GFS and to some extent the NAM versus the Euro/UKMET/GGEM. A blend between the 2 camps actually might work out pretty well for us, and that could be a good thing.

What I am saying is its much further north than the NAM or Euro.

Link to comment
Share on other sites

Explain if you would? :)

"Just a reminder of the crazy spread and extreme difficulty the models will have simulating these large upper tropospheric energetic waves as they break off the Pacific Jet. This is more challenging than large cyclones alone migrating across the Pacific.

The spread at 96 hours is pretty amazing."

post-999-0-00468000-1295648973.gif

post-999-0-43737900-1295648990.png

post-999-0-39640900-1295648997.png

The short blurb from this morning in central/western (above).

The models stink badly with these disturbances breaking off the Pacific jet. The exact timing/amplitude/strength is hard for the models to handle. They also pass through the BC mountains--and that doesn't help. The differences with the guidance seem to be propping up as early as 42 hrs into the forecast as they can't handle the orientation and what angle that second wave comes in. Moreover--some guidance has a dual wave configuration with the secondary wave and a stronger backside jet-- as a result, the differences by 84 hrs are huge and one camp has a digging wave into Mexico and the GFS takes the leading S/W eastward. Finally compunding the forecast challenge is the wave in the Pacific is rapidly developing so any of those early tiny errors I mentioned above eventually result in massive changes. Best thing to do now is go with the ensemble means regarding the height field configuration then base the forecast from there.

Link to comment
Share on other sites

I like the fact that an average of all guidance (GEFS, GFS, EC ens, EC, GGEM, GGEM ens) actually gives us a pretty good solution. Usually when all the major guidance is clustered around each other like this, a compromise solution ends up closer to reality. In this case a compromise works just fine. Even the warmer runs of the op GGEM and EC are not far from a major snowstorm. Taking a blend of the guidance at this time gives us a pretty good chance here. In past storms this was not true, we needed an outlier to win, or one extreme of the envelope of permutations. This time a blend of all guidance is a good result here. The other thing we have going for us is a favorable h5 track finally. I know its only on the models, but I have pointed out before that most of the storms this year did not have a favorable H5 track even on the guidance 5 days out. The surface looked good but h5 did not. I am more encouraged now that we have a legitinate chance at our first significant snow then I was when I first started talking about this threat several days ago.

Link to comment
Share on other sites

http://www.americanw...post__p__331423

Just a reminder of the crazy spread and extreme difficulty the models will have simulating these large upper tropospheric energetic waves as they break off the Pacific Jet. This is more challenging than large cyclones alone migrating across the Pacific.

The spread at 96 hours is pretty amazing.

post-999-0-00468000-1295648973.gif

post-999-0-43737900-1295648990.png

post-999-0-39640900-1295648997.png

The models stink badly with these disturbances breaking off the Pacific jet. The exact timing/amplitude/strength is hard for the models to handle. They also pass through the BC mountains--and that doesn't help. The differences with the guidance seem to be propping up as early as 42 hrs into the forecast as they can't handle the orientation and what angle that second wave comes in. Moreover--some guidance has a dual wave configuration with the secondary wave and a stronger backside jet-- as a result, the differences by 84 hrs are huge and one camp has a digging wave into Mexico and the GFS takes the leading S/W eastward. Finally compunding the forecast challenge is the wave in the Pacific is rapidly developing so any of those early tiny errors I mentioned above eventually result in massive changes. Best thing to do now is go with the ensemble means regarding the height field configuration then base the forecast from there.

I like the fact that while there are divergent solutions from the op models, the ensemble means of the EC, GGEM, and GFS are aactually fairly similar. Supports my comments above about a blend being a pretty good idea for now, as well as a pretty good solution for this area.

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

  • Recently Browsing   0 members

    • No registered users viewing this page.

×
×
  • Create New...