Jump to content
  • Member Statistics

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

The Psuhoffman Storm


Ji

Recommended Posts

Well, the trend on the GFS is undeniable..it is creeping north, but at the same time, the GFS is an outlier with this Miller Bish look.

Like Ji pointed out, on the NAM at 84, the storm is just starting to get together and on the GFS the thing is about over.

I would take the GFS in a heartbeat

but I'm not foolish enough to think that the trend won't stop at this run, especially when they all creeped north as the so-called "threat" got closer

Link to comment
Share on other sites

  • Replies 6.9k
  • Created
  • Last Reply

Look at the trends since 12Z. Pretty clear what it is doing.

What? . What trends are you talking about? The only model that has run since 12z is the GFS...the other model that ran is the NAM and it looks like all the other models

Link to comment
Share on other sites

Heck, take the Euro/NAM rainstorm I95 and east just to change it up. Different qpf amounts, and at least one storm with a different thermal profile, but come on this is 5 or 6 in a row now. And with, essentially, the same pattern of model depictions making the same errors with the snow depiction for our area in the +72 hr period.

Link to comment
Share on other sites

I wonder what you would have been saying in 1958 when up until mid February there had been almost no snow at all in Baltimore, then there were 2 HECS and a SECS from that point on.

if every threat had vanished like this year, I would have been saying the same thing

58' there was obviously a clear pattern change

the problem with this year has been the cold has been here, the snow has not

cold and dry with BN snow is pretty rare around here

the fact that we didn't really have a thaw to reshuffle the deck was, to say the least, disconcerting for snow hopes

like I said, I'll be happy to be wrong, but for things to turn this year based on the winter to date would be unprecedented for these parts

Link to comment
Share on other sites

I don't have much to add as I'm not even sure I fully understand why the NAM had (still has?) a drift in the large scale (though there are various hypotheses related to the model itself, various DA aspects including bias correction of satellite data, etc.). The NAM domain nowadays is actually quite large (see below)...so lateral boundary conditions shouldn't be an issue for most of the CONUS part of the domain for most of the integration.

I think that we've seen pretty big improvement since going to partial cycling instead of allowing the NAM to cycle on itself. I'm not in the meso-group, so I may not have this exactly right (I don't know exactly what what states they use and how far they go back for partial cycling...but basically before each analysis, the NAM is started from a previous GFS state (from 12 hrs ago all fields, not just the boundaries). Then, a series of analyses and forecasts of the NAM are run leading up to the actual initialization time, at which point the full 84 hour forecast is run (the lateral boundary conditions for this are updated using the previous GFS fcst, from 6 hours ago). I think the cycling is 3 hourly leading up to initialization time (in other words, it starts from a GFS forecast, assimilates obs, runs a short NAM forecast, assimilates more obs, runs another short NAM forecast, etc.). This allows the NAM to start from a large scale that is like the GFS, but try to resolve scales / features at its own resolution and consistent with its own dynamics. This essentially cuts off any possible "drift" in the large scale, at least relative to the GFS, since it's forced to do a complete restart from a global state very so often.

g110.12kmexp.jpg

Thanks for the NAM info--I was unaware that was how the NAM worked now. The partial cycling is an interesting idea. I will say it has become much better than it was at its pretty awful debut in 2006--still has some odd issues though. I will PM you some of the many I notice. Either way thanks for the info again.

Link to comment
Share on other sites

Let's see what the Euro says... I've already spent most of the disposable income out of today's paycheck on an assumption I would be in at home all weekend tracking a storm.lightning.gif But refuse to waist my weekend tracking another Miller B if the Euro starts folding.

Link to comment
Share on other sites

Wonder how many will be in this thread about 1 AM? I can see it though. We've been incredibly unlucky this year, especially the DC, NoVa crowd. Well, good luck to us. I don't think I can make it. Bring on the precip. Either kind.

really, this place will be a tinderbox in the spring (and all those winds) if we don't getting some precip

Link to comment
Share on other sites

If it verified verbatim, yes. But there has to be the fear that if the GFS is right with the Miller B look, we will get the 100 mile NE shift per usual.

Well yes, what I meant to imply was that if someone said pick a model run and it will happen, I'd take the 12Z GFS from today in a heartbeat. So yes, obviously taken verbatim, not taking into account any trends, etc. that it might possibly be indicating for later runs.

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...