Jump to content
  • Member Statistics

    17,586
    Total Members
    7,904
    Most Online
    LopezElliana
    Newest Member
    LopezElliana
    Joined

Post Christmas Bomb


Damage In Tolland

Recommended Posts

Another notable difference between the 12z and 00z Euro -- the energy diving down the east side of the upstream ridging while the low bomb on the coast -- on the 12z, it's able to hold back anticyclonic wave breaking, which is why the bomb doesn't decay as fast as it does on the 00z run.

Link to comment
Share on other sites

  • Replies 1.8k
  • Created
  • Last Reply

I have a basic (and OT) question about models.

What is the difference between the op run, the ensembles, and the ens mean? Conceptually, I understand the ens mean. But what does the model do to have different results in ensemble members? The op run?

I've never understood the "why" and "how" here.

They run different perturbations of the operational model run by changing up the physics. By doing this, this idea is to eliminate the wild model swings we see in the operational model run and it smooths it out when you take the mean.

Link to comment
Share on other sites

Morning JB for all the JB fetishers

The GFS out to sea scenario is because of its feedback bias and this is a classic case where it SHOULD BE WRONG. Why? It lives for handing systems off to the east away from the trough axis. However it is trending even further south and east. In the old days, this is a no brainer. The storm last week though means simply ripping it apart without considering it is foolish. But over the years, this has been a big problem with it, and its a problem with the physics in the model. Again you folks in NYC.. What storm in the past 10 years that delivered a foot of snow was forecasted to do that on this model 4-5 days away. Many times, it sees it 7-10 days away, takes it out and pulls it back in.

So if its wrong, it will be the same old song.

In the old days the european, once locking on, would be a no brainer on this. A lock on is 3 straight runs in a row of a monster and its doing it. Last nights run was wild again. The reason its so good would have to do with its superior physics and handling of feedback. However since a change was made to the model a few years ago, it has not been the guru it once was on the east coast. I dont know if their modelers have seen this or are aware, but operational forecasters are. Just like the GFS has a bias of handing energy out, the Euro has the bias of bundling it too much. However it is scoring its first coup, this is slower.. and in this case slower means stronger, wherever this winds up since it will then give time to clear the playing field in front of it What both models have in common and argue for the big mid atlantic northeast storm is the upper ridge on the west shore of Hudson bay. What happens with this, and why storms can turn up and explode is that the cold advection in back of the storm is strong enough to initiate feedback that deepens the storm which in turn causes warmth to flow in and that gets going in the battle also.

Link to comment
Share on other sites

They run different perturbations of the operational model run by changing up the physics. By doing this, this idea is to eliminate the wild model swings we see in the operational model run and it smooths it out when you take the mean.

Cool--I was just talking to my statistician-wife about my questino, and that's pretty much what we (she) concluded.

Link to comment
Share on other sites

Cool--I was just talking to my statistician-wife about my questino, and that's pretty much what we (she) concluded.

They are not as resolute as the op runs, but they are designed to incorporate all the inherent (well most) possibilities that the atmosphere might have. Some are tweaked with slightly different physics and some with slightly different initial conditions.

Link to comment
Share on other sites

I'm not going to lie...I'm more nervous about this storm than I was yesterday. 0z Euro was just about a perfect solution for coastal & eastern CT and I like the consistency with which its been bringing us a significant hit. But can't ignore the fact that the ensembles are further SE and that the other models trended away from a good hit last night. We really need the Euro to hold steady and other models to begin to trend.

Link to comment
Share on other sites

I don't think the ridge as modeled now is a problem. Look at February 1978 in your KU book...very similar super ridge centered over Montana with 564 dm heights into southern Canada.

The longitude of the ridge axis isn't necessarily a problem. It becomes an issue if we get anticyclonic wave breaking too early -- then we get something like the 00z Euro where the low cuts off too far south. If wavebreaking can be held back a little longer, like the 12z Euro, then it's PERFECT.

Link to comment
Share on other sites

The 0Z Euro may have been far south, but at least we all got a snowstorm. If the Euro backs down I think the alternative may be well out to sea....

The longitude of the ridge axis isn't necessarily a problem. It becomes an issue if we get anticyclonic wave breaking too early -- then we get something like the 00z Euro where the low cuts off too far south. If wavebreaking can be held back a little longer, like the 12z Euro, then it's PERFECT.

Link to comment
Share on other sites

Well the 6Z GFS is way way out to sea again. I can't say that I see clues on the old 84 hour NAM to suggest more support for the Euro. I really want the Euro to be right, but I have a sinking feeling that it is gonna blow it again and all of a sudden it will reverse course.

The models never waver when they show a cutter..........

Link to comment
Share on other sites

Maybe... LOL but my guess is by tomorrow sometime we know if the Euro is on crack and whether we need to waste more time on this - at least from location.

I see pain and heartache ahead. I see weenies missing Christmas dinner to see if the Euro Ensembles reverse an out to sea trend, then drunkenly flinging toys at the fire place when the 0Z GFS comes in Christmas night with a VA/NC special.

Link to comment
Share on other sites

I see pain and heartache ahead. I see weenies missing Christmas dinner to see if the Euro Ensembles reverse an out to sea trend, then drunkenly flinging toys at the fire place when the 0Z GFS comes in Christmas night with a VA/NC special.

After last weeks model mayhem, I remain skeptical, I will be happy with my 2-4" snows today......

Link to comment
Share on other sites

I have to really laugh at last nights Euro discussion Will explaind that the depiction was a 92 cold version with 2 " QPF yet people did not like the OP run? People like MPM would get annihilated with that 850 inflow. Op run strictly speaking one of the great runs ever for all SNE weenies, way too far away for any conclusion but 0 Z OP Euro has my vote for run of the year.

Link to comment
Share on other sites

It's a region centric thing...a cutter for you guys is anything from Albany to Minnesota.

True, But unlike last week when we were seeing 300 mile swings, You don't typically see a low thats forcasted to go thru eastern Ny state or thru the St Lawerence make that kind of move to a coastal scenario.......

Link to comment
Share on other sites

And I see that after this event, model consensus is building that we may have to endure a cutter and reload of the cold out around day 10 or so. This will be doubly depressing if it fails because we are looking at two weeks+ for the next chance maybe.

And December would be a loss as well......

Link to comment
Share on other sites

Ray was annoyed I think that he might get 1 to 2 feet instead of 2 feet plus. I hate to tell him he may be getting 1-2 inches at best if some of the other models are right. Goodness...all I want is maybe 6 inches around/just after Christmas. I don't set my sights at 2 feet.

I have to really laugh at last nights Euro discussion Will explaind that the depiction was a 92 cold version with 2 " QPF yet people did not like the OP run? People like MPM would get annihilated with that 850 inflow. Op run strictly speaking one of the great runs ever for all SNE weenies, way too far away for any conclusion but 0 Z OP Euro has my vote for run of the year.

Link to comment
Share on other sites

I have to really laugh at last nights Euro discussion Will explaind that the depiction was a 92 cold version with 2 " QPF yet people did not like the OP run? People like MPM would get annihilated with that 850 inflow. Op run strictly speaking one of the great runs ever for all SNE weenies, way too far away for any conclusion but 0 Z OP Euro has my vote for run of the year.

And it is great for you guys down that way, But when i start to see lows stalling around the delmarva, I start to raise an eyebrow as i have seen this dog and pony show to many times for the end result up this way.........

Link to comment
Share on other sites

The best thing for you guys in ME (maybe me too) is for the end to come for this wx pattern. The new pattern may not be way below normal in the East, but maybe we can score some snow - whether it be from overunning , etc.

And it is great for you guys down that way, But when i start to see lows stalling around the delmarva, I start to raise an eyebrow as i have seen this dog and pony show to many times for the end result up this way.........

Link to comment
Share on other sites

And it is great for you guys down that way, But when i start to see lows stalling around the delmarva, I start to raise an eyebrow as i have seen this dog and pony show to many times for the end result up this way.........

Yep SNE, this is where the NNE / SNE lines get crossed and why when things get closer in there are separate threads, more often than not we in SNE are on the sidelines while you guys are high fiving.

Link to comment
Share on other sites

Archived

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

Guest
This topic is now closed to further replies.
  • Recently Browsing   0 members

    • No registered users viewing this page.

×
×
  • Create New...