Holidays 2017-18 Mid-Long Range Disco 2

[aldie 22]

That storm on the 7th is the one

[PDIII]

We probably will have to wait until the pattern breaks down a little bit. These 1050 highs in the middle of the country are keeping the shortwaves to our south and shutting down the gom.

[Scraff]

2 hours ago, mitchnick said:

 

Lock it up and call it a day. I’m sure it’s gone at 12z. Hahaha  

Seriously, fingers crossed that this is the start of trend the right way. It’s only 5 days right!? Better than 10. 

[clskinsfan]

How can anyone look at anything the Gfs  is spitting out and put one iota of trust in it? It has been all over the place for the past couple of weeks. You have to trust what the Euro is saying. If for no other reason than climo alone. NS vorts that don' track under us are a heartbreak waiting to happen. A dead SS with cold push being forecast is not good for us either. I dont think we will be shut out completely over the next couple of weeks. But a few snow showers is a major disappointment after what ALL of the models were showing last week. 

[RevWarReenactor]

I think people need to be more positive. The models are showing potential all over the place. I think the majority of storms have never shown up in the long range.

I’d be shocked if we get out of this with nothing to show for it. It’s happrned sure....but I think one of these will deliver 

[CAPE]

6 minutes ago, clskinsfan said:

How can anyone look at anything the Gfs  is spitting out and put one iota of trust in it? It has been all over the place for the past couple of weeks. You have to trust what the Euro is saying. If for no other reason than climo alone. NS votes that don' track under us are a heartbreak waiting to happen. A dead SS with cold push being forecast is not good for us either. I dont think we will be shut out completely over the next couple of weeks. But a few snow showers is a major disappointment after what ALL of the models were showing last week. 

EPS has trended drier every run over the last few days. Now its a tenth or less of total precip for the entire region through day 8. Looks like a prolonged period of wasted cold. Cold and dry, a staple here.

[North Balti Zen]

Arctic outbreaks are awful for snow. I thought you all knew that. 

[mattie g]

4 minutes ago, North Balti Zen said:

Arctic outbreaks are awful for snow. I thought you all knew that. 

But...but...deep winter!!1!1!!

[frd]

9 minutes ago, North Balti Zen said:

Arctic outbreaks are awful for snow. I thought you all knew that. 

Ninas  are dry most times, combine that with your comments as well and then expectations are more reasonable. 

Would have been nice though for once the - NAO to happen.  I guess the SST profile has changed and hopefully next year the pattern starts to favor more NAO domain blocking. 

 

[WinterWxLuvr]

52 minutes ago, clskinsfan said:

How can anyone look at anything the Gfs  is spitting out and put one iota of trust in it? It has been all over the place for the past couple of weeks. You have to trust what the Euro is saying. If for no other reason than climo alone. NS vorts that don' track under us are a heartbreak waiting to happen. A dead SS with cold push being forecast is not good for us either. I dont think we will be shut out completely over the next couple of weeks. But a few snow showers is a major disappointment after what ALL of the models were showing last week. 

Is that the same Euro that gave us a snowstorm for this upcoming weekend?  The same gfs that said there wouldn’t be one?

[North Balti Zen]

16 minutes ago, mattie g said:

But...but...deep winter!!1!1!!

Indeed. Deep winter. High five to the hearing bills. And frozen ground. 

[mitchnick]

1 hour ago, clskinsfan said:

How can anyone look at anything the Gfs  is spitting out and put one iota of trust in it? It has been all over the place for the past couple of weeks. You have to trust what the Euro is saying. If for no other reason than climo alone. NS votes that don' track under us are a heartbreak waiting to happen. A dead SS with cold push being forecast is not good for us either. I dont think we will be shut out completely over the next couple of weeks. But a few snow showers is a major disappointment after what ALL of the models were showing last week. 

Can anyone look at any of them and believe it?  No.  The Euro has been just as bad as the Gfs.  Just in different ways.  The shortwave coming on shore at 78 hours on the 6z Gfs and the Nam is real. Here's a current pic of it just north of Hawaii. The Gfs gives one possible scenario how things play out.  It's no less or more likely than what any other model is currently showing imho.

 

[clskinsfan]

2 minutes ago, WinterWxLuvr said:

Is that the same Euro that gave us a snowstorm for this upcoming weekend?  The same gfs that said there wouldn’t be one?

Yeah. I get your point. But the dead southern stream is the problem for us in this upcoming pattern. The models are usually at least pretty good about telling us if the pattern is going to be active. Most were advertising a split flow with a moisture dump from Baja.  But they have been backing off of the stormy southern stream idea for the past few days. I guess you could say they were wrong last week so maybe they will be wrong this week as well. But it usually doesnt work that way for us. When the models say "no snow for you" they are usually spot on

[nw baltimore wx]

10 hours ago, high risk said:

It's not a different model.   It's the 12 km native model grid interpolated to a 32 km grid.     That's why it look the same.

This is probably banter but I think it has a better chance of being seen and answered here, but the above quote was in regards to similarities/differences on the 12km and 32km nams. I know that it was discussed a lot when the new nam was released, but I'm wondering when is each used by pros and better amateurs? I know the sarcastic answer is going to be never because the nam is dissed so much here, but we all know it has its usefulness, especially as its intended use, short range.

So, in looking at the subtle, and sometimes not so subtle differences of each run on the 3, 12, and 32km, how do those in the know use all three? 

[clskinsfan]

4 minutes ago, mitchnick said:

Can anyone look at any of them and believe it?  No.  The Euro has been just as bad as the Gfs.  Just in different ways.  The shortwave coming on shore at 78 hoirs on the 6z Gfs and the Nam is real. Here's a current porc of it just north of Hawaii. The Gfs gives one possible scenario how thongs play out.  It's no less or more likely than what any other model is currently showing imho.

 

Oh there is no doubt the vort is real. The question is will it dig all the way down to central Texas like the GFS is advertising? I guess with pressing 1058 HP over the top it is possible. 

[Buddy1987]

9 minutes ago, mitchnick said:

Can anyone look at any of them and believe it?  No.  The Euro has been just as bad as the Gfs.  Just in different ways.  The shortwave coming on shore at 78 hours on the 6z Gfs and the Nam is real. Here's a current pic of it just north of Hawaii. The Gfs gives one possible scenario how things play out.  It's no less or more likely than what any other model is currently showing imho.

 

The 12z Nam at 84 is much stronger with the shortwave over the pacific northwest when comparing it to the GFS, although the NAM went bonkers with a broken off piece from the Arctic front last night and I got all excited to wake up this morning and have it be completely different once again. That is here nor there at this point now. Bottom line is there are a lot of ways this thing can still trend positive for us. Would really like to see some support from the Euro or CMC on this. 

[MillvilleWx]

This is probably banter but I think it has a better chance of being seen and answered here, but the above quote was in regards to similarities/differences on the 12km and 32km nams. I know that it was discussed a lot when the new nam was released, but I'm wondering when is each used by pros and better amateurs? I know the sarcastic answer is going to be never because the nam is dissed so much here, but we all know it has its usefulness, especially as its intended use, short range.
So, in looking at the subtle, and sometimes not so subtle differences of each run on the 3, 12, and 32km, how do those in the know use all three? 

For forecasting, I use NAM 12km within 24-36 of a forecast as long as it hasn’t been ridiculously jumpy. The NAM can show a particular solution at range (48+ hours) and lock it in all the way to the end, so that’s when you want to give it more weight at range. Blizzard of 2016 is the best example. Last March snow to sleet storm is another example. The NAM is not to be used at all for Tropical, but it can on occasion score a coup with synoptic pattern at range, but you absolutely have to keep an eye on how the model has trended in its depiction at surface and H5. If it’s jumpy, probably best to discard until it gets inside 36 hours. It should have a better handle by then.

NAM Nest is best used for convective purposes and another piece of guidance to monitor trends in synoptic pattern. Inside 36 hours is when it becomes most practical. When I forecast for Texas and out west, it’s actually not bad on frontal progression, but can be overzealous at times on precip depiction. It’s a known bias for model to go overboard on certain setups like isentropic upglide, so you have to look at other models to get a feel for whether or not the 3km is seeing a greater potential.

The NAM isn’t the greatest model for our purposes a lot of the times because it’s projected more for the mesoscale and better handles convective setups and not broad synoptic scale patterns. Watch trends on guidance closely, see if it’s consistent on certain features at range. If it’s banging the drum over and over on something (Northern extent of precip field for 2016 Blizzard for example), then it might be on to something. Otherwise, it’s common for it to change its depiction at every run or every 12 hours. In terms of synoptic scale patterns, go with the big 4 (GFS, Euro, UKMET, and GEM) because they will generally have a better handle at range and even close in. Once inside 24 hours, meso models and just good ole surface and upper air analysis will tell you the story about what will unfold or is unfolding.


.

[clskinsfan]

The 12Z RGEM has a few snow showers through the area on Wednesday. The Euro was showing the same thing a couple of runs ago. Maybe someone can steal a quick half inch out of it?

[Bob Chill]

Just so we're on the same page, the shortwave responsible for doing what the GFS is doing is not out in the Pac. It's WAY up north in Canada near the arctic circle. This is the shortwave that digs down and amplifies the flow over the middle of the country. It's completely plausible but also unsupported by any other guidance. Hopefully the GFS scores one here. The Yukon Territories and regions in the arctic circle don't have a lot of data. Basically the only data models get from that region is satellite data. It's entirely possible the GFS is on to something and conversely it's entirely possible that the GFS is manufacturing something out of thin air. 

[usedtobe]

12 minutes ago, Bob Chill said:

Just so we're on the same page, the shortwave responsible for doing what the GFS is doing is not out in the Pac. It's WAY up north in Canada near the arctic circle. This is the shortwave that digs down and amplifies the flow over the middle of the country. It's completely plausible but also unsupported by any other guidance. Hopefully the GFS scores one here. The Yukon Territories and regions in the arctic circle don't have a lot of data. Basically the only data models get from that region is satellite data. It's entirely possible the GFS is on to something and conversely it's entirely possible that the GFS is manufacturing something out of thin air. 

Unfortunately in flow like this, Canada is often the driving force as the impulses in that flow can either help amplify a system or damp it depending on the timing.  So far,  it hasn't been our friend.  Also like you say, there is not a lot of data up there outside of polar orbiting satellite derived stuff so the models often have the details of the flow there wrong.  Hense the jumping from suppressed to storms from run to run. 

[mitchnick]

17 minutes ago, Bob Chill said:

Just so we're on the same page, the shortwave responsible for doing what the GFS is doing is not out in the Pac. It's WAY up north in Canada near the arctic circle. This is the shortwave that digs down and amplifies the flow over the middle of the country. It's completely plausible but also unsupported by any other guidance. Hopefully the GFS scores one here. The Yukon Territories and regions in the arctic circle don't have a lot of data. Basically the only data models get from that region is satellite data. It's entirely possible the GFS is on to something and conversely it's entirely possible that the GFS is manufacturing something out of thin air. 

Then the storm over Hawaii is in response to something else or that because when you move through the forecast, that system north of Hawaii comes crashing on shore at 78 hrs.

https://www.tropicaltidbits.com/analysis/models/?model=gfs&region=namer&pkg=mslp_pcpn_frzn&runtime=2017122606&fh=0&xpos=0&ypos=0

[Buddy1987]

GFS dropping a potent vort out of Canada. Closed contour at 90. It obv was there on the last run but it looks mighty impressive.

[Bob Chill]

1 minute ago, mitchnick said:

Then the storm over Hawaii is in response to something else or that because when you move through the forecast, that system north of Hawaii comes crashing on shore at 78 hrs.

https://www.tropicaltidbits.com/analysis/models/?model=gfs&region=namer&pkg=mslp_pcpn_frzn&runtime=2017122606&fh=0&xpos=0&ypos=0

The pac energy provide the precip. The shortwave way up in Canada provides the amplification. We need both. Without amplification, the pac shortwave will have the same sheared flat fate of the preceding 2 before it. 

[BristowWx]

Yes h5 looks butter at 90

[mitchnick]

Energy on shore at 90 hrs stronger than 6z

[Bob Chill]

1 minute ago, mitchnick said:

Energy on shore at 90 hrs stronger than 6z

Agreed. Unfortunately the northern shortwave isn't digging as far west as the last 2 runs. Could end up flatter/less amplified. 

[mitchnick]

Just now, Bob Chill said:

Agreed. Unfortunately the northern shortwave isn't digging as far west as the last 2 runs. Could end up flatter/less amplified. 

Noticed that too. Confluence a little stronger too. Ughh, damn cold air!  Lol

[Bob Chill]

1 minute ago, mitchnick said:

Noticed that too. Confluence a little stronger too. Ughh, damn cold air!  Lol

The euro/ukie looking very close to identical is a big flag. Never like it when a model is on their own D4+. Looks like this run will take a step towards the euro/ukie unfortunately. 

GFS looks ok with the pac shortwave though. Giving more room to try and do something. 

[Buddy1987]

3 minutes ago, Bob Chill said:

Agreed. Unfortunately the northern shortwave isn't digging as far west as the last 2 runs. Could end up flatter/less amplified. 

Surface looks good with overrunning setting up at least at 117. Really hoping this one over achieves.

[BristowWx]

1 minute ago, mitchnick said:

Noticed that too. Confluence a little stronger too. Ughh, damn cold air!  Lol

What am I missing. h5 is digging west of 6z.