ers-wxman1 Posted December 15, 2014 Share Posted December 15, 2014 still plenty of clock left for this game. Shifts like this are common. We will see this kind of waffling in the op runs for a couple more days. Good to see the ENS more clustered. Link to comment Share on other sites More sharing options...
ers-wxman1 Posted December 15, 2014 Share Posted December 15, 2014 If the posts are still very wide by Thursday, our min/most likely/max graphics will be quite a sight :-) Link to comment Share on other sites More sharing options...
dtk Posted December 15, 2014 Share Posted December 15, 2014 thx for that I wonder if they keep stats on the performance of each member like they do with the operational....and if so, which ones are better one would think they would but I don't know if it would be published The members use stochastic components (pseudo-random perturbations during the integration) to address model uncertainty. Also, one of the main tenets of a well-designed ensemble prediction systems is that any member should be as equally skillful as any other member (and the true state should fit in the ensemble envelope just as a member). I suspect a large enough sample would show that there are no members that are more skillful. I bet that one batch is slightly more skillful than the other. The ECMWF ensemble is well designed and well calibrated, and quantitative statistics bears this out. The only problem with the aforementioned for the ECMWF EPS is that some of the perturbations are cycled in time, and they use two classes of initial perturbations: 1) initial singular vectors, and 2) analysis based from their ensemble of 4DVARs. Regarding the earlier bits....their ensemble is 50 perturbed members (IC and stochastic model perturbations) + 1 control run (non perturbed) = 51 total members. Link to comment Share on other sites More sharing options...
WEATHER53 Posted December 15, 2014 Share Posted December 15, 2014 whoever posts this on facebook should be banned from the internet If you cluster everything together then a 998 low 75 miles east of the VA/MD border on the eastern shore with a 1025 high over southern tip of Hudson Bay would in fact produce those results. Link to comment Share on other sites More sharing options...
Bari Posted December 15, 2014 Share Posted December 15, 2014 If the posts are still very wide by Thursday, our min/most likely/max graphics will be quite a sight :-) lol, professional forum-caster Link to comment Share on other sites More sharing options...
Ellinwood Posted December 15, 2014 Share Posted December 15, 2014 12z Euro Ens still very much on point... expecting Euro Op to bounce back soon. Link to comment Share on other sites More sharing options...
paxpatriot Posted December 15, 2014 Share Posted December 15, 2014 Regarding the earlier bits....their ensemble is 50 perturbed members (IC and stochastic model perturbations) + 1 control run (non perturbed) = 51 total members. So, should we consider the control run just "another ensemble member", or is there something more specific to be gained by looking at it? Link to comment Share on other sites More sharing options...
mitchnick Posted December 15, 2014 Share Posted December 15, 2014 The members use stochastic components (pseudo-random perturbations during the integration) to address model uncertainty. Also, one of the main tenets of a well-designed ensemble prediction systems is that any member should be as equally skillful as any other member (and the true state should fit in the ensemble envelope just as a member). I suspect a large enough sample would show that there are no members that are more skillful. I bet that one batch is slightly more skillful than the other. The ECMWF ensemble is well designed and well calibrated, and quantitative statistics bears this out. The only problem with the aforementioned for the ECMWF EPS is that some of the perturbations are cycled in time, and they use two classes of initial perturbations: 1) initial singular vectors, and 2) analysis based from their ensemble of 4DVARs. Regarding the earlier bits....their ensemble is 50 perturbed members (IC and stochastic model perturbations) + 1 control run (non perturbed) = 51 total members. thx for that explanation Link to comment Share on other sites More sharing options...
WEATHER53 Posted December 15, 2014 Share Posted December 15, 2014 thx for that explanation Stochastic. Is that anythign like fantastic??? Link to comment Share on other sites More sharing options...
dtk Posted December 15, 2014 Share Posted December 15, 2014 So, should we consider the control run just "another ensemble member", or is there something more specific to be gained by looking at it? It is sort of like a "baseline" run for the perturbed members. A few things: 1) It is like the operational run except that it is run at lower (ensemble) resolution (T639 instead of T1279). 2) It does not have it's own data assimilation, but uses a truncated analysis from the OP 3) Since the ensemble is coupled to a dynamic ocean model, I am assuming that the control forecast is as well (the deterministic OP run is not coupled to an ocean model, only a wind-wave model). The control will exhibit somewhat different behavior than the members since it does not include the stochastic physics parameterizations (SKEB, SPPT). There is more reading on their system available here: http://old.ecmwf.int/research/ifsdocs/CY40r1/IFSPart5.pdf In a sense, yes, you can consider it like "another member of the ensemble". I would not look it on its own like we do the operational deterministic (high resolution) integration since it lacks assimilation, etc. Link to comment Share on other sites More sharing options...
dtk Posted December 15, 2014 Share Posted December 15, 2014 Stochastic. Is that anythign like fantastic??? Obviously.... sto·chas·tic stəˈkastik/ adjective randomly determined; having a random probability distribution or pattern that may be analyzed statistically but may not be predicted precisely. Link to comment Share on other sites More sharing options...
WxUSAF Posted December 15, 2014 Share Posted December 15, 2014 12z Euro Ens still very much on point... expecting Euro Op to bounce back soon. In general, it seems like the Euro Op and the ensembles don't often diverge very much compared to the GEFS and GFS Op. The differences on the 12z runs between the Euro Op and ensembles, particularly when other model systems now agree quite well with the Euro ensembles are a red flag IMO. Link to comment Share on other sites More sharing options...
yoda Posted December 15, 2014 Share Posted December 15, 2014 50/50 low still holding strong on 18z GFS at 81 hrs Link to comment Share on other sites More sharing options...
Bari Posted December 15, 2014 Share Posted December 15, 2014 dtk, I've got a question, Instead of using a control run for the ensambles, why don't they just used the OP run as a conrol since it's running on a higher resolution. The truncation analysis limits the ens control runs max and mins anyways anyways, it seems like your basically trying to keep the ens control run as close in line with the OP. It seems weird, but would it save computing time just to simplify the system and only used the OP as your control run for the ens? Link to comment Share on other sites More sharing options...
yoda Posted December 15, 2014 Share Posted December 15, 2014 1014 L S LA at 108 on 18z GFS Link to comment Share on other sites More sharing options...
dtk Posted December 15, 2014 Share Posted December 15, 2014 dtk, I've got a question, Instead of using a control run for the ensambles, why don't they just used the OP run as a conrol since it's running on a higher resolution. The truncation analysis limits the ens control runs max and mins anyways anyways, it seems like your basically trying to keep the ens control run as close in line with the OP. It seems weird, but would it save computing time just to simplify the system and only used the OP as your control run for the ens? Except that it is not then representative of the other members. The control member will include the same physics as the other members (which is different than the OP), and resolution can make a big difference. Plus, it is dynamically coupled to an ocean model with makes things quite a bit different. Having a control member to compare to the OP helps to quantify where/why/how the ensemble may be different. It also helps understand and correct for systematic biases between the high resolution configuration and the lower resolution ensemble configuration. Link to comment Share on other sites More sharing options...
paulythegun Posted December 15, 2014 Share Posted December 15, 2014 1014 L S LA at 108 on 18z GFS a smidge more organized through 108 (than the 12z run) but still comically disorganized Link to comment Share on other sites More sharing options...
Bari Posted December 15, 2014 Share Posted December 15, 2014 Except that it is not then representative of the other members. The control member will include the same physics as the other members (which is different than the OP), and resolution can make a big difference. Plus, it is dynamically coupled to an ocean model with makes things quite a bit different. Having a control member to compare to the OP helps to quantify where/why/how the ensemble may be different. It also helps understand and correct for systematic biases between the high resolution configuration and the lower resolution ensemble configuration. thanks, that makes a lot sense Link to comment Share on other sites More sharing options...
MillvilleWx Posted December 15, 2014 Share Posted December 15, 2014 The difference between the strength and orientation of the shortwaves between the GFS Op and Euro Op are night and day. The GFS is weaker with both pieces and it basically lags the northern s/w behind the southern system causing it to be a weak wave that just comes and goes. Interested to see the PGFS compared to its last solution. Link to comment Share on other sites More sharing options...
Ian Posted December 15, 2014 Share Posted December 15, 2014 Serious sprinkles on the GFS. I'm riding that bad boy. Link to comment Share on other sites More sharing options...
paulythegun Posted December 15, 2014 Share Posted December 15, 2014 Serious sprinkles on the GFS. I'm riding that bad boy. I enjoyed how the low dissipated when it reached the hostile confines of the warm Atlantic Ocean Link to comment Share on other sites More sharing options...
ers-wxman1 Posted December 15, 2014 Share Posted December 15, 2014 18z GFS is sheared crapola to the south. Unphased and OTS. A little waa from the initial upper wave but that's it. Link to comment Share on other sites More sharing options...
yoda Posted December 15, 2014 Share Posted December 15, 2014 Parallel GFS 1013 L C AL at 120 132 in southern SC Link to comment Share on other sites More sharing options...
Ian Posted December 15, 2014 Share Posted December 15, 2014 11 years of non stop trolling........... Me, the GFS, or both? Link to comment Share on other sites More sharing options...
Deck Pic Posted December 15, 2014 Author Share Posted December 15, 2014 PARA Link to comment Share on other sites More sharing options...
WxUSAF Posted December 15, 2014 Share Posted December 15, 2014 18z GFS is sheared crapola to the south. Unphased and OTS. A little waa from the initial upper wave but that's it. Hot garbage. Xbox looks to keep a similar solution to 12z. Link to comment Share on other sites More sharing options...
yoda Posted December 15, 2014 Share Posted December 15, 2014 BOOM PARA Link to comment Share on other sites More sharing options...
usedtobe Posted December 15, 2014 Share Posted December 15, 2014 PARA That's what I thought. It looks nothing like its older cousin. Probably not good for me but the northwestern snow belt would like it. Link to comment Share on other sites More sharing options...
EasternUSWX Posted December 15, 2014 Share Posted December 15, 2014 Hey now. Link to comment Share on other sites More sharing options...
olafminesaw Posted December 15, 2014 Share Posted December 15, 2014 PARA Similar track, a stronger low. Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.