Holidays 2017-18 Mid-Long Range Disco

[MountainGeek]

2 minutes ago, Wonderdog said:

Sorry but what does taint mean. 

Temps in some or most of the column rise to the point where we no longer get nice clean fluffy snow -- rain/mix/sleet/ice or all of the above at various points during the storm.

[MountainGeek]

Just now, Bob Chill said:

Taint your *** and taint your **** oh wait, that's a different taint. Mixed precip. That's all. 

Ninja'd by the Chill Master....

[Wonderdog]

1 minute ago, MountainGeek said:

Ninja'd by the Chill Master....

Taint that the truth.

[Scarlet Pimpernel]

Hmm, looks like RR hacked Chill's account there!  'Taint a doubt about it! 

But seriously in response to Wonderdog's question, yes, "taint" just refers to not all snow...where you end up mixing with or changing over to freezing rain/sleet, and perhaps get all rain for a time.

[Bob Chill]

I just thought of something worth pointing out. We're about in the same range for the upcoming storm that the GFS/GEFS were in when it was digging the trough out west and ruining Christmas with a ridge. Ever since then the trend was to back off on the western trough, mute the SE ridge and speed things up. This is probably something to keep in mind with the GFS/GEFS right now. If it's a common bias we can expect next week's event to potentially do similar things. It will be a good test and something to pay attention to over the next 4-5 days. 

 

 

[stormy]

The OOz Monday ECM and GEM both gave temperatures in the 60's on Christmas day. The GFS was the only one correct with temperatures in the 30's.

[Scraff]

Just caught up reading for the last four hours of analysis. Great job to everyone for keeping it real!  Looks like legit winter weather will soon come to fruition. TAINT no doubt about it. 

[Bob Chill]

Check this out. 

GEFS @ 180 hours from the 12z run on Saturday:

 

This is today's 18z gefs panel for the same time stamp:

 

 

That's a pretty big difference. It's completely normal for guidance to shift like this though. We're 180 hours out from the event we're tracking. Something to keep reminding ourselves....a lot can and will change coming up. One of the differences next week is we aren't tracking a big pattern change anymore. It will be well established by then so I don't think there will be huge changes over the next week but even little things can mean a lot with a discreet event. 

 

 

 

[Chris78]

2 minutes ago, Bob Chill said:

Check this out. 

GEFS @ 180 hours from the 12z run on Saturday:

 

This is today's 18z gefs panel for the same time stamp:

 

 

That's a pretty big difference. It's completely normal for guidance to shift like this though. We're 180 hours out from the event we're tracking. Something to keep reminding ourselves....a lot can and will change coming up. One of the differences next week is we aren't tracking a big pattern change anymore. It will be well established by then so I don't think there will be huge changes over the next week but even little things can mean a lot with a discreet event. 

 

 

 

 Thats a great point.Seems to be a bias of the models this winter season. (Holding back energy far out in time).

 Ive been a long time reader going back several years and as someone who just start posting recently i just wanted to say you do an awesome job explaining technical aspects of the pattern in a way that's easy to understand and makes sense. When you post I definitely pay attention. Thanks for all the great knowledge you pass on in this forum. I've learned so much over the years and still continue to learn from the group of knowledgeble posters on here.

[Interstate]

11 minutes ago, Bob Chill said:

Check this out. 

GEFS @ 180 hours from the 12z run on Saturday:

 

 

This is today's 18z gefs panel for the same time stamp:

 

 

 

That's a pretty big difference. It's completely normal for guidance to shift like this though. We're 180 hours out from the event we're tracking. Something to keep reminding ourselves....a lot can and will change coming up. One of the differences next week is we aren't tracking a big pattern change anymore. It will be well established by then so I don't think there will be huge changes over the next week but even little things can mean a lot with a discreet event. 

 

 

 

Hey everyone makes mistakes when you drink hard on a Friday night.  The GFS was a little hungover on Saturday

[nj2va]

10 minutes ago, Bob Chill said:

Check this out. 

GEFS @ 180 hours from the 12z run on Saturday:

This is today's 18z gefs panel for the same time stamp:

That's a pretty big difference. It's completely normal for guidance to shift like this though. We're 180 hours out from the event we're tracking. Something to keep reminding ourselves....a lot can and will change coming up. One of the differences next week is we aren't tracking a big pattern change anymore. It will be well established by then so I don't think there will be huge changes over the next week but even little things can mean a lot with a discreet event. 

 

 

 

Good reminder that things can and will evolve.  If we believe the GFS’ evolution (which is entirely plausible), it seems a big factor determining the track is the trough out west and how high it can cause heights to pump in the east.  Certainly something to keep an eye on with future GFS runs.

[psuhoffman]

12 minutes ago, Bob Chill said:

Check this out. 

GEFS @ 180 hours from the 12z run on Saturday:

 

This is today's 18z gefs panel for the same time stamp:

 

 

That's a pretty big difference. It's completely normal for guidance to shift like this though. We're 180 hours out from the event we're tracking. Something to keep reminding ourselves....a lot can and will change coming up. One of the differences next week is we aren't tracking a big pattern change anymore. It will be well established by then so I don't think there will be huge changes over the next week but even little things can mean a lot with a discreet event. 

 

 

 

The guidance keeps wanting to dig a trough down the west coast and pump a ridge in the east in the long range. But in reality these things have been transient breaks that swing right back to the general -epo -AO central/eastern trough look that's been dominant for a while now.  Maybe it's the reverse of last year where guidance kept wanting to see a -nao that just never actually would last more then a quick transient day or two. 

[packbacker]

15 minutes ago, Bob Chill said:

Check this out. 

GEFS @ 180 hours from the 12z run on Saturday:

 

This is today's 18z gefs panel for the same time stamp:

 

 

That's a pretty big difference. It's completely normal for guidance to shift like this though. We're 180 hours out from the event we're tracking. Something to keep reminding ourselves....a lot can and will change coming up. One of the differences next week is we aren't tracking a big pattern change anymore. It will be well established by then so I don't think there will be huge changes over the next week but even little things can mean a lot with a discreet event. 

 

 

 

Was looking at this too...the EPS from 5 days ago for the same time. 

[AfewUniversesBelowNormal]

At one point, the cutoff ridge was over +500dm. There was no Greenland ridging, and nothing close to ridging in the N Pacific. What a change. (I call this change 2000s weather)

[psuhoffman]

Back to the question about the gefs tracks looking at the individual members there are only 5 that seem to take an (oh no) cutter track. Then there is a camp of 7 that look like a decent or better snow. Then another camp of 8 that squash the event or it so delayed it's hard to tell if it's the same thing.  One thing to note is the best snow solutions have a west to east track a bit north of where we typically want. But there is only one member that climbs the coast. The rest that get this under us end up suppressing it so much that it's weak sauce or a Richmond south snow not ours. So be careful what you root for. This doesn't look like something that's going to turn the corner. We might be better off with a snow to ice solution then if it all slides out south. 

[gymengineer]

3 hours ago, psuhoffman said:

I know some just like to do it and there is nothing wrong then if it's just entertainment but for usefulness it's too soon for detailed parsing of every shift of op runs. Some people are going to go crazy These threats are still at the range where looking at the general setup on the ensembles is the way to go. Pattern looks good. We have legit threats. From this range there are usually things that can go wrong and this is no different. But i see the potential. 

Maybe some want to and that's totally fine but I'll go crazy if I start breaking down every run now. For now I'm just glancing at the ops then digging a bit deeper into each ensemble run to get a general sense of the setup. 

I agree. My main takeaway from the 12Z operational suite was that it’s too early to tell. When you have 24-hr differences in the models on which wave amplifies in the mid-south (GEM and UKMET a day ahead of GFS and Euro), we don’t even know which day is our best shot yet. Thursday? Friday? Saturday? Two of those days?

[WxUSAF]

5 minutes ago, psuhoffman said:

Back to the question about the gefs tracks looking at the individual members there are only 5 that seem to take an (oh no) cutter track. Then there is a camp of 7 that look like a decent or better snow. Then another camp of 8 that squash the event or it so delayed it's hard to tell if it's the same thing.  One thing to note is the best snow solutions have a west to east track a bit north of where we typically want. But there is only one member that climbs the coast. The rest that get this under us end up suppressing it so much that it's weak sauce or a Richmond south snow not ours. So be careful what you root for. This doesn't look like something that's going to turn the corner. We might be better off with a snow to ice solution then if it all slides out south. 

Yeah, certainly a cutter cluster.  

What jumped out to me beyond the 29-31 period was a strong signal for a classic Miller A track around the 2nd-4th.  Way out there obviously, but it's fairly unusual to see a closed contour low like that at D12+ leads.  

[psuhoffman]

24 minutes ago, WxUSAF said:

Yeah, certainly a cutter cluster.  

What jumped out to me beyond the 29-31 period was a strong signal for a classic Miller A track around the 2nd-4th.  Way out there obviously, but it's fairly unusual to see a closed contour low like that at D12+ leads.  

Definitely a strong signal there. I noticed a huge spike in mean snowfall there then when looking at the individual members an inordinate amount for that range show a classic miller a coast climber in that window. If you extend the window to Jan 2-5 to account for timing differences at that range I might even be a majority that have it. About as strong a signal as you will see that far out. It's shown up on a few op runs also. But I didn't go into it much given the main focus of most in here is the day 8-10 event. 

I think that event favors a west to east hybrid miller b type system. The key will be the location of the high and what latitude the system ultimately tracks. But I favor a thump snow to ice. Those can work in this setup.  Let the arctic cold come in behind.  Then the one after we root for an amped up miller a bomb. 

One of the things I like best about this pattern is we seem to have multiple ways and multiple chances to score a win. 

[nj2va]

Question for the more knowledgeable folks here...if the trend this season is for weaker s/w, that would support a more suppressed/flatter solution (a lot not a cutter)?  But working in our favor would be the moisture train/STJ streaming up from Baja, in terms of getting precip here even if its a flatter solution?

[mattie g]

 

1 hour ago, Wonderdog said:

Sorry but what does taint mean. 

Grundle

[clskinsfan]

1 hour ago, MountainGeek said:

Ninja'd by the Chill Master....

Dont feel bad. He does it to me all of the time.

[Bob Chill]

14 minutes ago, nj2va said:

Question for the more knowledgeable folks here...if the trend this season is for weaker s/w, that would support a more suppressed/flatter solution (a lot not a cutter)?  But working in our favor would be the moisture train/STJ streaming up from Baja, in terms of getting precip here even if its a flatter solution?

It seems that the ull/trough southwest of baja in the Pac is going to feed prolific stj moisture into the conus. Models have been seeing this since way out there in time and it's not going away. Pretty locked in. 

Because of that feature and also return flow in the gulf, it won't take a strong shortwave to tap into it. Our biggest fear is probably missing to the south. No guidance is showing that type of suppression though. 

It's an interesting setup. There's a lot of wiggle room on this and that's unusual. Even a weak shortwave can still be a prolific precip maker. Some of the runs a few days ago showed a massive ice storm in the lower midwest and Texas and the shortwave was hard to even see. Lol. Just a plume of moisture running into cold with no strong vorticity anywhere near it.  When I saw those solutions I realized that this is a really good setup for a big storm somewhere. 

It's entirely possible that there are back to back events (for someone) next week. The euro had that at 12z. Two pieces exited the Rockies and both tapped the same juice. Cool stuff.  

[DC2Winston]

Would it be safe to say this potential 12/28-12/30 event would not benefit both my area and DC, snow wise? Meaning tracks right over me and benefits places DC and north? Or is somehow suppressed and it becomes a VA/NC border special.

[Roger Smith]

In the background, I think the main story here is gradual model recognition of the reality that the energy peak that will dominate arrives later, around Jan 1-3, and not this first one that the GFS has been advertising. As soon as the GEM downgraded the high to a more realistic central pressure, this energy shift began to show up there, and it's already with the EURO. 

I can't guarantee that the second energy peak will eventually deliver a big snowstorm, but I do think it has a better chance than the first wave which I expect to get flattened out by each cycle of the GFS starting with the 00z. It may just settle into being a decent 4-7" type snowfall that is followed by deeper cold and a good set up for Jan 1-3. 

 

[Wonderdog]

4 minutes ago, Roger Smith said:

In the background, I think the main story here is gradual model recognition of the reality that the energy peak that will dominate arrives later, around Jan 1-3, and not this first one that the GFS has been advertising. As soon as the GEM downgraded the high to a more realistic central pressure, this energy shift began to show up there, and it's already with the EURO. 

I can't guarantee that the second energy peak will eventually deliver a big snowstorm, but I do think it has a better chance than the first wave which I expect to get flattened out by each cycle of the GFS starting with the 00z. It may just settle into being a decent 4-7" type snowfall that is followed by deeper cold and a good set up for Jan 1-3. 

 

That wouldn't be hard to take but you're assuming the GEM is correct from over what six or seven days out? Just asking since the accuracy of any of the long range models is suspect at best.

[Roger Smith]

More of a comment that the GEM was wrong about the 1060 mb high that was part of its humungous storm scenario, when it dropped to a more realistic 1045-50, that went away and the more favorable second energy was more prominent.

But not an endorsement of its solution, it still looks a bit off to me even after the reality check. 

Part of the complexity here is that much of the high pressure in part one of this build-up is trapped in the inter-mountain west and oozes out into Texas, this is not easy for models usually, then the second push is more classic prairies to Midwest into Quebec, so how these two parts link up seems to be confusing the models. And if they're confused, we're confused. 

[Deck Pic]

Gonna wait to get invested in this one. We’re too far out. My WAG is thump > flip. Which would be cool. Any snow in December is awesome. 

[Kleimax]

Looking like a Christmas miracle on the 00z gfs 

[das]

6 hours ago, gymengineer said:

The last time, I think, was 12/16/89-12/25/89 (10 days). I don't think there's been any since, but that's just going off of checking the cold stretches I can remember. The end of 1/04 came pretty close, but there was a one day interruption in the midst of an 8-day stretch. 

Good stats. I was in CA at that time so missed that cold stretch. We’ll get a stretch like that up here in northern MoCo every once in a while but uber-warm DCA is just so rare. Will be interesting to see what verifies up here if it really happens. Ice pond hockey for everyone!  (...and, certainly, skating on the C&O Canal!). 

[mitchnick]

At 114 hrs., cold press from the North over the midwest looks better to me suggeting it stays south. But time wil tell.