Jump to content
  • Member Statistics

    17,606
    Total Members
    7,904
    Most Online
    ArlyDude
    Newest Member
    ArlyDude
    Joined

December 2017 Mid-Long Range Disco 2


WxUSAF

Recommended Posts

  • Replies 1.5k
  • Created
  • Last Reply
4 minutes ago, mitchnick said:

None of the ensembles had this.

I disagree. Maybe not as extreme as the 12z op but even the 6z gefs had close to half the members burying energy in the SW while we ridge out. The epo ridge is working against us this time. It's opening the door for bad solutions like we're seeing. 

Link to comment
Share on other sites

8 minutes ago, Bob Chill said:

I disagree. Maybe not as extreme as the 12z op but even the 6z gefs had close to half the members burying energy in the SW while we ridge out. The epo ridge is working against us this time. It's opening the door for bad solutions like we're seeing. 

I should have been clearer. None days ago like 5+. Now that we get closer,  they finally catch on, but I thought the purpose of the ensembles was to give a decent idea on the mid and long range. The means (5+days ago) never looked like what the Gfs is selling today.

Link to comment
Share on other sites

1 minute ago, mitchnick said:

I should have been clearer. None days ago like 5+. Now that we get closer,  they finally catch on, but I thought the purpose of the ensembles was to give a dent idea on the mid and long range. The means (5+days ago) never looked like what the Gfs is selling today.

It's the epo standing vertical (and narrow) and then closing off. This allows weakness underneath so energy can easily dig under it instead of progress. If you want to root against something right now then root against the epo ridge closing off or being so narrow and vertical off the west coast. That's our enemy for sure. 

Link to comment
Share on other sites

A Rage Against the Machine song is running in my head....Know Your Enemy...the lyrics don't apply but the title does. 

The GFS was a disaster obviously but the main reason is also on the Euro. To repeat my previous post, here's a visual of the epo ridge standing tall and closing off. The process starts at hr 108+/- so it's not in the LR anymore. 

52YOQMl.gif

 

Once the ridge closes off there is weakness underneath. Energy diving south down the front of the EPO ridge has an easy time moving westward into the weakness. Down stream this allows the SE ridge to amp up even more. 

 

Here's the 0z euro @ hr 168. It never closes off the EPO ridge. Gets really close but doesn't and that keeps the pattern more progressive than the GFS just showed us. 

ecmwf_z500a_namer_9.png

 

Either way, a trough axis in Colorado is rarely a good sign for folks in the east. GFS is further west with the axis and the end result is a disaster. Do I think the EPO ridge closing off is locked in? No, I don't at all. In fact, I would favor a more progressive pattern than what the GFS just tossed out. But even with a progressive pattern, it's a process to get things right in our hood for snowfall. And unless quick changes for the better happen in the next 2 days, we can probably write off getting on the good side of any boundary before Christmas. I'm hoping just like everyone else that we thread the needle here. But now trends in the med range are moving against us and this is a period where ops actually have some skill. 

Link to comment
Share on other sites

17 minutes ago, Bob Chill said:

A Rage Against the Machine song is running in my head....Know Your Enemy...the lyrics don't apply but the title does. 

The GFS was a disaster obviously but the main reason is also on the Euro. To repeat my previous post, here's a visual of the epo ridge standing tall and closing off. The process starts at hr 108+/- so it's not in the LR anymore. 

52YOQMl.gif

 

Once the ridge closes off there is weakness underneath. Energy diving south down the front of the EPO ridge has an easy time moving westward into the weakness. Down stream this allows the SE ridge to amp up even more. 

 

Here's the 0z euro @ hr 168. It never closes off the EPO ridge. Gets really close but doesn't and that keeps the pattern more progressive than the GFS just showed us. 

ecmwf_z500a_namer_9.png

 

Either way, a trough axis in Colorado is rarely a good sign for folks in the east. GFS is further west with the axis and the end result is a disaster. Do I think the EPO ridge closing off is locked in? No, I don't at all. In fact, I would favor a more progressive pattern than what the GFS just tossed out. But even with a progressive pattern, it's a process to get things right in our hood for snowfall. And unless quick changes for the better happen in the next 2 days, we can probably write off getting on the good side of any boundary before Christmas. I'm hoping just like everyone else that we thread the needle here. But now trends in the med range are moving against us and this is a period where ops actually have some skill. 

Bob, great post and the ensemble mean pushes that ridge west with time so even after we get the good shot of cold after Christmas, it's staying power is suspect as the ridge off the west coast dos allow the southeast ridge to come back.  However, the last image on the GEFS suggests that the ridge might be shifting back east and we keep cross polar flow through the the end of the run. 

Link to comment
Share on other sites

12 minutes ago, usedtobe said:

Bob, great post and the ensemble mean pushes that ridge west with time so even after we get the good shot of cold after Christmas, it's staying power is suspect as the ridge off the west coast dos allow the southeast ridge to come back.  However, the last image on the GEFS suggests that the ridge might be shifting back east and we keep cross polar flow through the the end of the run. 

Yea, I unfortunately agree with things not really getting right down the line. With a +ao/nao combo look coming up I'm keeping expectations in check. We do have a very cold dump of air coming into the conus so even with a +ao/nao, there will be some unusually cold air around. One of the key ingredients for a flawed or lucky event. It seems we're entering a period that isn't particularly bad or good. Sorta right in the middle. Which is always better than a shutout pattern. We've been avoiding those pretty well so far this year. This week coming up isn't pretty but it's not going to lock it seems. Hopefully we score during the last week of the month. Would cap off a half decent Dec for these parts.  

 

ETA: A little bit of a se ridge could end up being a net +. Cold and dry is useless. Maybe the ridge helps put our area in the battlezone. Way too far down the line to get into details. Just saying that a se ridge isn't always a bad thing. 

Link to comment
Share on other sites

7 minutes ago, Bob Chill said:

During cold enso winters they happen often enough. There is nothing particularly unusual about the upcoming 10 day progs. 

....and since what we need for snow is hard to come by, no breath holding! Lol

The only real positive we have going for us is that the models have proven their progs beyond 3 days stink. Not time to jump, but the chances of a decent couple of events a few days look unlikely at this point. 

Link to comment
Share on other sites

GFS ensembles dominant pattern is warming at 10mb and 30mb Alaska-Northern Canada. Pos NAO in a few days isn't real because it's just vortex rotating around, which I think models are handling poorly wrt to around Christmas wet storms. New feature on model 12z, which I think could be a growing signal in days that follow is 500mb reflection of upper Stratosphere ridge... . Expect Arctic stable block to continue to show up at 500mb Pattern shift was Dec 8th. This is a cold and snowy pattern for a while. 

f108.gif

Link to comment
Share on other sites

1 minute ago, Bob Chill said:

We have op consensus now. Very slow moving boundary with 2 rounds of rain and a warm Christmas is showing on the gfs, cmc, and euro. 

Cmc never really bought the cold and snowy/wintry solution. It and its counterpart, Rgem,  have done well this year (with predictions of snow and no snow). We should keep this in mind down the road. There usually is one model suite that prevails over the others each season.

Link to comment
Share on other sites

I think he still believes the warmth will be pushed out of the way before or on Christmas

I think the consistency of the models still isn't fully there (the 0z Suite of OPs believed that it would be cold on Christmas), but as we get closer to Christmas, the models will become more consistent, which is probably what we're seeing here

Link to comment
Share on other sites

3 minutes ago, mitchnick said:

Cmc never really bought the cold and snowy/wintry solution. It and its counterpart, Rgem,  have done well this year (with predictions of snow and no snow). We should keep this in mind down the road. There usually is one model suite that prevails over the others each season.

Considering the lead were talking, the ensembles should get the grade and not the ops. The gefs definitely wins there. It picked up on the stubborn SE ridge/big dig in the west staying through the holiday first. By a big margin too. The gefs was bashed and made fun of for it too. Heh

12z is probably rock bottom. I don't think it can get worse. The euro is an unmitigated disaster. 

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

Guest
This topic is now closed to further replies.
  • Recently Browsing   0 members

    • No registered users viewing this page.

×
×
  • Create New...