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January Banter 2020


George BM
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2 hours ago, PhineasC said:

Great job with your model reading lately, keep up the good guessing. 

Reality is in just about every winter we get 2-4 weeks where the pattern is favorable enough for snow in most of this region. We possibly "wasted" one already, so we  might have another 2-3 weeks somewhere between now and mid March. Modeled "perfect" patterns often don't work out. The upcoming advertised pattern looks like a shutout on the means, but it may not turn out that way. My guess is that one or 2 chances will materialize over the next few weeks during transient cold periods, and maybe we(someone's yard) will get lucky. If not, It tends to find ways to snow in February around here.

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23 minutes ago, WinterWxLuvr said:

 Not even sure what a super ensemble is lol.

Having never looked into it, I have always thought of it as a 'smart' version of the regular ensembles.

I just Googled it, and here is an academic technical overview of a super ens modeling system:

https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2015RG000513

The notion of the multimodel superensemble was first described in Krishnamurti et al. [1999]. This utilizes a training and a forecast phase. The training phase learns from the recent past performances of models and is used to determine statistical weights from a least square minimization via a simple multiple regression. That regression is carried out with respect to analyzed (assimilated) values. Given a number of grid locations, base variables, forecast intervals, and a suite of models, the number of statistical weights can be as high as 107. That many coefficients are needed because of different responses to physical parameterizations of local features such as water bodies, local mountain features, and land surface details within diverse member models. These details contribute to systematic errors in forecasts. The high skill of the superensemble comes from a domain average of the point by point RMS errors that it is minimizing. 

 

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11 minutes ago, C.A.P.E. said:

Having never looked into it, I have always thought of it as a 'smart' version of the regular ensembles.

I just Googled it, and here is an academic technical overview of a super ens modeling system:

https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2015RG000513

The notion of the multimodel superensemble was first described in Krishnamurti et al. [1999]. This utilizes a training and a forecast phase. The training phase learns from the recent past performances of models and is used to determine statistical weights from a least square minimization via a simple multiple regression. That regression is carried out with respect to analyzed (assimilated) values. Given a number of grid locations, base variables, forecast intervals, and a suite of models, the number of statistical weights can be as high as 107. That many coefficients are needed because of different responses to physical parameterizations of local features such as water bodies, local mountain features, and land surface details within diverse member models. These details contribute to systematic errors in forecasts. The high skill of the superensemble comes from a domain average of the point by point RMS errors that it is minimizing. 

 

And I was thinking that there is an anomaly map that comes from this super ensemble, maybe FSU? Same look as those gfs maps you linked for me.

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5 minutes ago, WinterWxLuvr said:

And I was thinking that there is an anomaly map that comes from this super ensemble, maybe FSU? Same look as those gfs maps you linked for me.

There might be. I don't look at them that often- typically it's when we are being teased with an h5 look that is promising.

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3 hours ago, nj2va said:

You forgot to add that your post was sponsored by the Euro.  :p

There’s been plenty of instances that the models shifted looks in the MR this winter.  I guess I’m in the “crowd” that reminds people that looks can change from a D15 smoothed out mean.  Yes, models have gotten better over time but I don’t take a D15 look as 100% set in stone since it never is.  

The gefs has more fluke runs that show some divergent nonsense because they run 4 times a day and have a follow the leader issue and less members.  Plus they gave a cold bias at range you have to take into account.  But if you take them in 48 hour chunks (ignore a couple fluke runs) and account for the bias they were always indicating problems ahead also imo. 

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32 minutes ago, PrinceFrederickWx said:

I calculated the monthly snow averages at BWI since the 10/11 winter:

DEC: 1.0"

JAN: 7.9"

FEB: 4.8"

MAR: 4.1"

Definitely going to see some big changes in the new 30 year normals when they come out (this summer?)

Not really... going into this season BWI is averaging exactly 20" over the last 29 years.  Their old 30 year average was 20.1 so they are only off by 1/10 of an inch.  Even if BWI only gets 5" this season their new 30 year avg would be 19.5"  That is only a 0.6" change from the current avg.  And that assumes this year is god awful.  If BWI makes it to near normal their 30 year avg will remain virtually unchanged.  

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16 minutes ago, psuhoffman said:

Not really... going into this season BWI is averaging exactly 20" over the last 29 years.  Their old 30 year average was 20.1 so they are only off by 1/10 of an inch.  Even if BWI only gets 5" this season their new 30 year avg would be 19.5"  That is only a 0.6" change from the current avg.  And that assumes this year is god awful.  If BWI makes it to near normal their 30 year avg will remain virtually unchanged.  

Overall average won't change but we'll be seeing big changes as to how we get there month-to-month. It should be a return to the historical norm where March snow > December snow.

(By the way, the monthly changes was what I was referring to, not the total. I think you may have misunderstood my post).

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13 minutes ago, PrinceFrederickWx said:

Overall average won't change but we'll be seeing big changes as to how we get there month-to-month. It should be a return to the historical norm where March snow > December snow.

(By the way, the monthly changes was what I was referring to, not the total. I think you may have misunderstood my post).

I missed that...sorry.  We went through a long stretch where March snowfall was virtually extinct compared to earlier periods.  Lately things have flipped back and the new averages will reflect that.  You are correct. 

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5 minutes ago, WxWatcher007 said:

Is it tropical season yet? :cry:

You need to reap Bob asap.  He is bad for business spreading hope and shiit like that.  EPO ridge pushing into AK...Scandinavian ridges...lights at ends of tunnels..workable patterns coming in quicker.  I think you know what needs to be done!   

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