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Pattern December, Make analogs relevant again

GaWx said:
I must admit to not liking that the last 3 GEFS runs have had a slight increase in the SE ridging with each run during the 11-15 day period vs the prior one but hopefully this trend is just a burp. It looks too Ninaish too early vs analogs. This is the type of thing I'd expect to see more in the last half of Jan and in Feb, when a Niña tends to be ugliest for the SE, than late this month when QBO/ENSO/-AO analogs say cold returns to the SE and continues into early Jan.
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Yeah the last few have been a little aggressive with the ridge however the 06z GEFS absolutely tanks the EPO, like it's literally almost off the chart negative . Add to that many eps members turn the US into the arctic in the LR. I still feel really good rolling forward. Seeing some of the ensemble runs does give cause for a pause . Thankfully we get the GEFS every six hours so I'll just pick the best looking one of the day !!!
 
Hope springs eternal ...

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tennessee storm said:
Still interested more Xmas timeframe ... mjo heading into phase 1 and 2. Stormy cold phase
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I do like the EPS' MJO prediction into a long period staying in phase 8, one of the coldest phases in the SE in Dec, while it weakens. Weak MJO wouid generally be better than strong per MDA mets but this also matches research I've done (looking at actual SE temperature anomalies day by day). Per those mets, the general idea of a weak MJO would minimize warmer influences from the tropics and allow the northern jet to have more influence in the E US...therefore colder tendencies. Hopefully there will be no SE ridge to screw this up.
 
Per MDA met this morning:

"1-5 and 11-15 Day Similarities/Differences

After a warm 6-10 Day period, the forecast reverts back to a colder regime in the 11-15 Day. The overall pattern themes echo some similar themes to that of the near-term, particularly in the eastern Pacific as the EPO heads back into its negative phase after a brief sojourn to the positive side in the 6-10 Day, resulting in a strong upper-level ridge building over western Canada and Alaska while troughing deepens downstream across the eastern half. While the general pattern shape is very similar, there are some notable differences in the details that preclude the period from resembling a carbon copy of the 1-5 Day. The western ridge is shifted further west in the 11-15 Day than the 1-5 Day, which results in a colder outcome across the Rockies compared to the very warm 1-5 Day. However, it is worth noting that the Euro and especially the GFS had the ridge being too far west ten days ago when today’s 1-5 Day period was 11-15 Days out, and as a result, the GFS in particular was far too cold in the West and Plains. Meanwhile, both ensembles (but especially the GFS) show some ridging over the Southwestern Atlantic during the 11-15 Day, which aims to prevent cold from reaching as far south as in the 1-5 Day period."

For those fearing the dreaded SE ridge, this observation by this MDA met is encouraging in that it suggests an eastward shift of the western US ridge/eastern US trough couplet will verify vs what the recent GEFS runs have been showing for the 11-15. If this E shift for the current 11-15 were to verify similarly to what is happening in the current 1-5, that would mean that the GEFS SE ridge is a fake.
 
CMC looks way out in left field and is just as progressive as the NAVGEM, and is noticeably faster than the GFS w/ this trough. Probably will see big adjustments from this model over the coming days. As with the last system, once it actually figured out the large-scale synoptic flow pattern and wasn't trying to shove the coastal low towards Bermuda it wasn't all that bad...
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LovingGulfLows said:
German model says it want to amp up the western ridge and dig the vort more, similar to last weekend's storm.

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Yeah the GFS is trending towards a solution like this and its not really all that unrealistic given how NWP faired and trended in the last event... This is definitely the type of storm that can sneak up on people
 
OMG at the potential associated with the wild pattern suggested by the 12Z GFS in the 11-15 with that very strong western ridge and accompanying extremely cold air that includes 850s of -32C in MN/two Arctic highs coming down as well as no end in sight at the end of the run. Don't worry about the details like storms this far out. Just marvel at the potential with this type of pattern.
 
GaWx said:
Per MDA met this morning:

"1-5 and 11-15 Day Similarities/Differences

After a warm 6-10 Day period, the forecast reverts back to a colder regime in the 11-15 Day. The overall pattern themes echo some similar themes to that of the near-term, particularly in the eastern Pacific as the EPO heads back into its negative phase after a brief sojourn to the positive side in the 6-10 Day, resulting in a strong upper-level ridge building over western Canada and Alaska while troughing deepens downstream across the eastern half. While the general pattern shape is very similar, there are some notable differences in the details that preclude the period from resembling a carbon copy of the 1-5 Day. The western ridge is shifted further west in the 11-15 Day than the 1-5 Day, which results in a colder outcome across the Rockies compared to the very warm 1-5 Day. However, it is worth noting that the Euro and especially the GFS had the ridge being too far west ten days ago when today’s 1-5 Day period was 11-15 Days out, and as a result, the GFS in particular was far too cold in the West and Plains. Meanwhile, both ensembles (but especially the GFS) show some ridging over the Southwestern Atlantic during the 11-15 Day, which aims to prevent cold from reaching as far south as in the 1-5 Day period."

For those fearing the dreaded SE ridge, this observation by this MDA met is encouraging in that it suggests an eastward shift of the western US ridge/eastern US trough couplet will verify vs what the recent GEFS runs have been showing for the 11-15. If this E shift for the current 11-15 were to verify similarly to what is happening in the current 1-5, that would mean that the GEFS SE ridge is a fake.
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Definitely noticeable how much cooler our supposed warm up late next week has trended in guidance of late and the EPS was less optimistic about the SE US ridge vs the GEFS a week or so ago, the 11-15 day on this GEFS suite will probably result in a repeat performance w/ overzealous ridging in the SE US while the EPS is likely closer to reality. Models tend to perform poorly in setups like this with a ton of low level arctic air being thrown into the contiguous US, see it time & time again the SE US ridge is too strong vs reality and the cold pushes deeper into the SE US. Should be a telling sign when the EPS (which is biased towards SW US upper level troughs) shows less troughing than the GEFS in the extended range over the southwest US. Of course, on americanwx none of this really seems to matter and some just prefer to blindly run away w/ the warmest solution at whatever cost, if even a similar solution in said model (GEFS) recently busted horribly...
 
GaWx said:
OMG at the potential associated with the wild pattern suggested by the 12Z GFS in the 11-15 with that very strong western ridge and accompanying extremely cold air that includes 850s of -32C in MN/two Arctic highs coming down as well as no end in sight at the end of the run. Don't worry about the details like storms this far out. Just marvel at the potential with this type of pattern.
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I was just about to post that you were gonna love the 12z gfs lol
 
GaWx said:
OMG at the potential associated with the wild pattern suggested by the 12Z GFS in the 11-15 with that very strong western ridge and accompanying extremely cold air that includes 850s of -32C in MN/two Arctic highs coming down as well as no end in sight at the end of the run. Don't worry about the details like storms this far out. Just marvel at the potential with this type of pattern.
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HAHA! Love the optimism of this post. It was a great run...


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Webberweather53 said:
Lol I love how NC still finds a way to get sleet and freezing rain in GFS fantasyland w/ a coastal low...
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We really gotta get rid of some of these big red Ls up near the Lakes. I know they're not the be all end all, but they are generally not very helpful. I like the potential in the pattern though. Not boring. I also like your other post about the warm-up not being as vigorous as advertised earlier. A lot of good winters behave that way. Usually, we get the opposite. I like how we're starting off.
 
GaWx said:
OMG at the potential associated with the wild pattern suggested by the 12Z GFS in the 11-15 with that very strong western ridge and accompanying extremely cold air that includes 850s of -32C in MN/two Arctic highs coming down as well as no end in sight at the end of the run. Don't worry about the details like storms this far out. Just marvel at the potential with this type of pattern.
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Rain Cold said:
We really gotta get rid of some of these big red Ls up near the Lakes. I know they're not the be all end all, but they are generally not very helpful. I like the potential in the pattern though. Not boring. I also like your other post about the warm-up not being as vigorous as advertised earlier. A lot of good winters behave that way. Usually, we get the opposite. I like how we're starting off.
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They are overrated! I mean you were worried about it with the last storm, and all for not! Raleigh scored big, I mean Houston! :)
 
Will be interesting to see how the Euro and Ukie pan out. The way NC can really score here is we get enough separation between this coastal low on day 5 which is liable to crush the mid-Atlantic and the NE US and a possible frontal wave that develops near the tail end of the front, as was shown a few runs ago on the Euro. If this one primary low completely takes over we could certainly afford some backside token flakes or modest snowfall accumulations but it wouldn't amount to much outside the mountains, far NW piedmont, or VA border. Regardless, if we manage to at least pull of some snow TV in Raleigh from this, it would be quite an accomplishment to see snow twice by mid-December.
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Brick Tamland said:
I saw snow on Dec 9. A lot sooner than I usually see snow here.
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Yeah, the average first accumulating snowfall in RDU (when we do observe accumulating snow) comes by about January 2nd on average, given the pattern that lays ahead, we definitely have some chances to break out earlier than normal this year...
 
Webberweather53 said:
Yeah, the average first accumulating snowfall in RDU (when we do observe accumulating snow) comes by about January 2nd on average, given the pattern that lays ahead, we definitely have some chances to break out earlier than normal this year...
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A good reminder for folks.
 
Would this weekends potential be any colder than this last weekend? East of the mountains still seems to not have a good cold air source.
 
GFS has a little clipper trending south Wednesday night over the last 4 runs. Not normal for clipper trends. Have to get a kid from school in NOVA so hope Fridays system moves south for you guys!!
 
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