• Member Statistics

    16,545
    Total Members
    7,904
    Most Online
    ampongabezo
    Newest Member
    ampongabezo
    Joined
Sign in to follow this  
WxUSAF

December Medium/Long Range Discussion

Recommended Posts

6z Euro at 90 has some very noticeable height rises along the East Coast compared to 0z.  More neutral tilt with the trough as well out west.  (Just signed up for Maue's site yesterday so I am playing around with it for now!)

  • Like 3
  • Thanks 1

Share this post


Link to post
Share on other sites

I'm with Leesburg, I'd like to start seeing the Euro and EPS come around to shifting north, even if just slightly today at 12z.  I certainly don't think the models have locked into a solution but we'll soon be closing in on 100 hours out so time will be running short on Euro making moves.  

Share this post


Link to post
Share on other sites

Good to see the storm to our south at this juncture. Expect a jog north without much confluence to block the storm from coming north. If we are still shooting blanks come Thursday 00z, id worry. We’re still 6 days out. No need to be worrying quite yet. At this point, we just need to be looking at the 500 mb pattern and teleconnections. The rest will get nailed down as we get closer. Storm is coming. That’s what’s most important at this point.  That being said... DC May finally be in a better position than Baltimore for this one. 

Share this post


Link to post
Share on other sites
8 minutes ago, BTRWx's Thanks Giving said:

update?

It's my understanding that it only goes out to 90.

 

Edit: Ninja'd

  • Thanks 1

Share this post


Link to post
Share on other sites

Hmmm, interesting , a few mets I read online have stated the potential for this event to move North 

Also, Webb posted this too, and then I looked back to see what actually happened.  

If this is indeed the storm he is mentioning , as the dates seem to match it did effect DC and Baltimore 

MSLP patterns aside, I believe it was way colder before and during the 1988 event,  versus how things are currently.  

https://www.nytimes.com/1988/01/09/us/storm-hits-east-coast-after-burying-south-in-snow.html

 

 

 

Share this post


Link to post
Share on other sites
6 minutes ago, LP08 said:

It's my understanding that it only goes out to 90.

 

Edit: Ninja'd

A main purpose of the off hour Euro runs is to provide boundary and initial conditions for regional models used by member states. 

  • Like 1

Share this post


Link to post
Share on other sites
10 minutes ago, psuhoffman said:

It only goes to 90

interesting. when did the euro start running at 0600 and 1800?  as reliable as the normal runs?

Share this post


Link to post
Share on other sites
2 hours ago, pasnownut said:

actually check that.  Hi risk and i were discussing the other day and he said that it is too big an undertaking and they dont have the resources to convert the GEFS to Fv3.  I think you'll have a new Op to stare at w/ same old GEFS for longer range viewing.  I'll dig back through my posts and see if i can find it.  Need more coffee/dramamine first.

FV3-based GEFS will not be implemented until early FY 2020 (probably Q2...e.g. about Jan 2020).  Some of this is driven by human and compute resources as there is a requirement for a 30 year reforecast for calibration before implementation.

1 hour ago, dallen7908 said:

"Starting with the 00Z 19 December cycle, the FV3-GFS uses GFDL microphysics instead of the Zhao-Carr microphysics in the GFS."

Saw this in the information (i) section of the FV3-GFS comparison site.  Is this referring to 2018 or 2017?

 

Definitely 2017.  All official retrospectives and real-time experiment use the Lin-type GFDL MP scheme.

  • Like 4
  • Thanks 5

Share this post


Link to post
Share on other sites

This is going to be the once every hundred year screw job for our area. We have been screwed to the south plenty of times before. But it just doesnt happen in December. Although NOV was a top 5 cold for most of us as well. Who knows at this point. But I was worried about it being squashed late last week when I saw that ridiculous confluence to the north. In all honesty the models have really stuck with that theme for the past 4 days. Yes some runs relax it enough to get the precip up to us. But I am not really feeling great about this one. Hope I am wrong.

Share this post


Link to post
Share on other sites
4 minutes ago, clskinsfan said:

This is going to be the once every hundred year screw job for our area. We have been screwed to the south plenty of times before. But it just doesnt happen in December. Although NOV was a top 5 cold for most of us as well. Who knows at this point. But I was worried about it being squashed late last week when I saw that ridiculous confluence to the north. In all honesty the models have really stuck with that theme for the past 4 days. Yes some runs relax it enough to get the precip up to us. But I am not really feeling great about this one. Hope I am wrong.

The most consistent model so far with this storm is basically right where we all want it.

  • Like 1

Share this post


Link to post
Share on other sites
8 minutes ago, dtk said:

FV3-based GEFS will not be implemented until early FY 2020 (probably Q2...e.g. about Jan 2020).  Some of this is driven by human and compute resources as there is a requirement for a 30 year reforecast for calibration before implementation.

Definitely 2017.  All official retrospectives and real-time experiment use the Lin-type GFDL MP scheme.

Daryl,  How do the FV3 scores compare with the GFS?  Right now I use it as another ensemble member.  

  • Thanks 1

Share this post


Link to post
Share on other sites

I wrote this on my Facebook page this morning.  I don't think any of the forecast problems outlined yesterday concerning the potential of a winter storm over the weekend have been resolved. The ensembles are not quite as bullish for snow as yesterday but there are enough members giving us moderate to heavy snow to not yet buy last night's (Monday night/early Tuesday morning) GFS and European runs which keep the bulk of the precip to our south. The parallel 06Z GFS still is a big hit and the Canadian model has the low tracking up the Chesapeake Bay introducing the possibility of rain. Those models and the heavier ensemble members argue to still keep all the options open ranging from the snow staying to our south to a significant (greater than 4" snowstorm) Besides, at these time ranges it's easy for the models to shift 100 miles north between now and Sunday.  My thoughts from last night's runs.  

  • Like 10
  • Thanks 9

Share this post


Link to post
Share on other sites
20 minutes ago, dtk said:

FV3-based GEFS will not be implemented until early FY 2020 (probably Q2...e.g. about Jan 2020).  Some of this is driven by human and compute resources as there is a requirement for a 30 year reforecast for calibration before implementation.

Definitely 2017.  All official retrospectives and real-time experiment use the Lin-type GFDL MP scheme.

Thanks for the clarification.

 

Share this post


Link to post
Share on other sites
6 minutes ago, snowmagnet said:

If we actually get this storm, is the timing now late Sunday into Monday? Also, I'm keeping track of the various models. What did the latest Ukie say?

Seems to be Sunday afternoon into early Monday. Something like that 

  • Like 1

Share this post


Link to post
Share on other sites

Well, the ICON is starting off 12z poorly.  Way south and barely any precip into va.  Including SW VA.  Good thing its just the ICON.

Share this post


Link to post
Share on other sites

I just took at look at FV3 bias scores... there still seems to be some room for improvement.  The below charts are for temps at 850 hPa and 1000 hPa (near sea level) over North America for the last month.  There's a similar bias for H5, but I'm not sure how meaningful that is.  The FV3 does well for H5 anomaly correlation, which I think is more important.

4yA4TY4.png

GZOC4Qn.png

Share this post


Link to post
Share on other sites
6 minutes ago, WxUSAF said:

@dtk tell us all why the superior physics and data assimilation techniques of the FV3 have locked in our snow here. Please? :ph34r:

It's all part of our plan to get people to pay attention.  In reality, it is going to be dead wrong.

5 minutes ago, usedtobe said:

Daryl,  How do the FV3 scores compare with the GFS?  Right now I use it as another ensemble member.  

This is a pretty solid implementation, considering that we haven't had a chance to put a ton of new science into the package (outside of the model dynamics and MP scheme, a few DA enhancements, etc.).   For things like extratropical 500 hpa AC, it has gained us about a point (about what we'd expect/want from a biannual upgrade).  Improvements are statistically significant. 

I should caution, our model evaluation group has noted that there are times where the FV3-based GFS appears to be too progressive at longer ranges.  It's not clear how general this is and for what types of cases this has been noted.  

  • Like 4
  • Thanks 1

Share this post


Link to post
Share on other sites
2 minutes ago, LP08 said:

Well, the ICON is starting off 12z poorly.  Way south and barely any precip into va.  Including SW VA.  Good thing its just the ICON.

The flow is even more suppressive over the northeast. The last 48 hours that feature us fluctuating some but in general is not trending better 

  • Like 1

Share this post


Link to post
Share on other sites
2 minutes ago, cae said:

I just took at look at FV3 bias scores... there still seems to be some room for imrpovement.  The below charts are for temps at 850 hPa and 1000 hPa (near sea level) over North America for the last month.  There's a similar bias for H5, but I'm not sure how meaningful that is.  The FV3 does well for H5 anomaly correlation, which I think is more important.

Yes, the cool/low height bias with increasing forecast time is already well known and documented.  In fact, I am pretty sure there is already a fix for this particular issue, though it is too late to include in the Jan. 2019 implementation.

  • Thanks 1

Share this post


Link to post
Share on other sites
9 minutes ago, LP08 said:

Well, the ICON is starting off 12z poorly.  Way south and barely any precip into va.  Including SW VA.  Good thing its just the ICON.

It wasn't even close either.  Hopefully the GFS doesn't head in the same direction.

Share this post


Link to post
Share on other sites

Since no one else will do it I will. The nam at 84 is significantly more amplified with the stj and less suppressive with the NS then even the 6z Fv3. It's the nam at 84 so...but if we're gonna bring up the icon might as well mention it.  

  • Like 6
  • Thanks 1
  • Haha 3

Share this post


Link to post
Share on other sites
Just now, nj2va said:

It wasn't even close either.  Hopefully the GFS doesn't head in the same direction.

Really suppressive over the NE.  Through 39 on the GFS, all I notice so far is that it is slower compared to 6z.

  • Like 1

Share this post


Link to post
Share on other sites
Just now, nj2va said:

It wasn't even close either.  Hopefully the GFS doesn't head in the same direction.

It tries for a late capture and tug North but not enough. Thats a feature on a few runs now. Maybe it trends towards a frintrunner wave that escapes and a secondary that comes up.  Doubtful though. Our big problem is the NS vorts diving through New England right in front and so far those features remain. 

  • Like 1

Share this post


Link to post
Share on other sites
1 minute ago, psuhoffman said:

Since no one else will do it I will. The nam at 84 is significantly more amplified with the stj and less suppressive with the NS then even the 6z Fv3. It's the nam at 84 so...but if we're gonna bring up the icon might as well mention it.  

ICON seems like its really on its own alot of times...sometimes good for weenies and then you have today. It dosent seem like a good model

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
Sign in to follow this  

  • Recently Browsing   0 members

    No registered users viewing this page.