December 2017 Observations and Discussions

[OKwx2k4]

@ Okwx, nice looking maps down there for ya, ey??? The coming 500mb pattern post 4th-6th system is going to carve out one deep trough across our sub forum. Things are going to get interesting.

 

 

 

 

Yup. May be a December to remember for me. I'm ready for it!

[OKwx2k4]

I don't ever remember seeing an AO modelled like that ever. That's impressive.

[OKwx2k4]

That's (2) potent systems closely spaced just like we had in early October. Hopefully, someone scores flakes now that we're two months down the road.

I think I will this time. I was looking forward to these storms coming back again.

[Craig-OmahaWX]

Gfs now took away the entire system letting the northern stream win out LOL

[Jaycee]

Gfs now took away the entire system letting the northern stream win out LOL

Was just about to say the same thing. I mean it doesn't even do a thing lol, just completely obliterates it almost. Yuck. We'll see what the EURO does, GFS always pulls this at this range anyway.

[Minny_Weather]

I don't see the 12z GFS being accurate in regards to the flow. It brings back that yucky Western ridge, which I think is kinda unrealistic. I'll buy it when I see more runs.

[St Paul Storm]

The GEM tries putting something together around the same timeframe that the GFS runs showed yesterday. Doesn’t quite come together but the idea is there.

[Snowlover76]

Nice to see the Dakotas getting it again after we have weeks of boring wx.

 

 

 

This is a carbon copy of last year. Uggghhh

[jaster220]

Nice to see the Dakotas getting it again after we have weeks of boring wx.

 

 

 

This is a carbon copy of last year. Uggghhh

 

 So far they've got cyber snow on cyber Monday, so I hope they have fun cyber shoveling!    

[Niko]

Man, looking at my December Outlook (10day that is) shows that temps really cool down quite a bit. I stand a good shot in not getting outta the 20s for highs. Lots of peeps on here will feel the December chill. Now, all we need is a storm to combine it with. Someone will get blasted. Question is, who?!

[St Paul Storm]

12z Euro says “What storm?”

[Minny_Weather]

Yeesh. I hope this is just models ingesting bad data, because both Euro and GFS keep the ridging throughout their runs.

[Stormgeek]

Even with the factors we have coming together I am becoming weary of something resembling previous (unspeakable) years. Mother nature could at least throw....something this this way. Time to move to Canada.

[Niko]

12z Euro says “What storm?”

The ensembles look good as of now for some action, especially (Colder Air coming). There has to be a storm somewhere where both airmasses separate.

[St Paul Storm]

The ensembles look good as of now for some action, especially (Colder Air coming). There has to be a storm somewhere where both airmasses separate.

You would think so. The GFS runs prior to today’s 12z were showing exactly that....a storm riding up the demarcation line. Let’s hope today’s midday model runs were them getting ‘lost’.

[Craig-OmahaWX]

Euro completely cuts the storm off and goes to nw flow up here. Hope this changes fast

[Craig-OmahaWX]

I know better then to get suckered into this. I think the northern stream wins out.

[jaster220]

That's (2) potent systems closely spaced just like we had in early October. Hopefully, someone scores flakes now that we're two months down the road. 

 

Wow, we could really have fun with a pair like this, even adjusting for latitude 

 

 

 

In fact, as the first storm continues to weaken and push east through Monday another one will quickly move in behind it. That area of low pressure is also forecast to undergo bombogenesis and strike the Aleutian Islands late Monday into Tuesday at a similar intensity to this past weekend's storm.

[hlcater]

Euro completely cuts the storm off and goes to nw flow up here. Hope this changes fast

Known euro bias to park energy as a cutoff low over the southwest, keep this in mind.

[jaster220]

Euro completely cuts the storm off and goes to nw flow up here. Hope this changes fast

 

Euro being the Euro, loves to over-do troughs and hang energy back in the SW. 

[Tom]

Known euro bias to park energy as a cutoff low over the southwest, keep this in mind.

To add to this, unlike last year, the overall flow is much better as we have not seen cut-offs in the SW at all this Autumn. This year, we have seen “kickers” upstream to keep the flow moving. I also believe it’s all the blocking that’s screwing with the modeling.

[Niko]

Sometimes models become confused w pattern change, so it takes a while for them to get adjusted and see things the correct way.

[Niko]

You would think so. The GFS runs prior to today’s 12z were showing exactly that....a storm riding up the demarcation line. Let’s hope today’s midday model runs were them getting ‘lost’.

Yup...models tend to sometimes get disorganized w any sort of pattern change.

[jaster220]

@ Tom

 

What is the lag-time for the BSR again? If that weekend storm (call it the 11/25 storm) cycles thru the stream, what dates would that be? Is it 10-17 days, or is that the EAR? I think the models are having major issues figuring out the pattern shift that lies ahead. What do you think?

[Craig-OmahaWX]

Oh i"ve seen the same thing said over and over again. I'm not too optimistic about this. I could actually see the NW flow cutting off the storm since the blocking has been so high lately. 

 

Hopefully it changes back though.

[Niko]

During the course of these upcoming days, I believe we will see new outcomes on the models.

[Tom]

@ Tom

 

What is the lag-time for the BSR again? If that weekend storm (call it the 11/25 storm) cycles thru the stream, what dates would that be? Is it 10-17 days, or is that the EAR? I think the models are having major issues figuring out the pattern shift that lies ahead. What do you think?

17-21 days...and EAR is 6-10 days later...I have found it's usually centered around 7-8 days using the EAR to forecast longer range patterns/storms.  TBH, I think the models are just having a tough time figuring out what to do with the energy.  I mean, we are talking about a storm that is still over a week away.  It'll come back, just not sure about track this far out just yet.  It may end up being a 2-part system with a northern cutter and then a secondary low along the boundary.  Highly amplified patterns produce some wide range ideas at this range.

 

FWIW, both 12z GEFS/EPS still hinting at a wintry solution for the Plains states for this system.  I don't think we will get any consistency over the next few days.  Some EPS members show big hits in NE/KS and even into parts of the Midwest.  

[Snowlover76]

I'm expecting nothing.

[Craig-OmahaWX]

I'm expecting nothing.

Best thing to do my friend. Nebraska doesn't get winter storms anymore lol.

[FV-Mike]

Accuweather thinking the pattern change coming around the 8th

 

[Craig-OmahaWX]

18z gfs more of the same as 12z. Weak flow and nw flow wins out. Sadly think this is what will happen. Gfs seems to have had good handle on storms weakening as they get closer

[Minny_Weather]

The lack of a storm isn't quite as disappointing as the lack of cold air that 12z/18z are showing. Let's wait till we get 00z data. Remember, 18z pretty much relies on 12z data.

[Niko]

Accuweather thinking the pattern change coming around the 8th

 

90.jpg

What a beauty of a map. Now, all we need is a storm and we are all set.

[Craig-OmahaWX]

What a beauty of a map. Now, all we need is a storm and we are all set.

Patterns like that do not support big southwest / ohio valley low pressure systems. Just more of the same northwest flow with quick hitting flurries and snow showers. 

[Niko]

Patterns like that do not support big southwest / ohio valley low pressure systems. Just more of the same northwest flow with quick hitting flurries and snow showers. 

Clipper type systems can sometimes overproduce in this NW flow and turn out to be a heck of a storm by tapping in on some GOM moisture and thats all it really takes to receive some appreciable accumulations. We just need the GOM to be open for business to tap in that moisture and then, we are in business as well.

[Craig-OmahaWX]

With how much I've been negative, looking forward to the 0z model runs and hopefully a flip back to what we have been seeing. Heck wouldn't even mind an all rain event.

[Niko]

GFS is very cold and active approaching mid December w a tanking NAO and a huge PNA ridge.

[Hawkeye]

DVN on next week.

Models certainly have shifted away from last night's consistency

in deterministic model runs as the extended forecast's significant
storm potential is now as chaotic as a cat rodeo.

[Andrew NE]

Gary Lezak's winter forecast is up in his blog.

[OKwx2k4]

Accuweather thinking the pattern change coming around the 8th

 

90.jpg

Too far east. There's no indication that an eastern solution here is even viable.