Jump to content
  • Member Statistics

    17,787
    Total Members
    7,904
    Most Online
    Cabby
    Newest Member
    Cabby
    Joined

December 2022 Medium-Long Range Disco


WxUSAF
 Share

Recommended Posts

Btw, guidance has me expecting an ice storm down here of epic proportions (Augusta County) based on latest euro and gfs and respective ensemble convergence.

So, knowing what I know about freezing rain verifying here (even with 1550’) and my climo being in this general area for 30 years, I am 99% sure I will be seeing cold rain and will be teaching young adults Thursday and Friday and not having snow/winter weather days!

Hope the northern/eastern crew gets lots of accumulating snow though!  You all are still in the game

Link to comment
Share on other sites

16 minutes ago, WesternFringe said:

Makes sense since the planet spins at 1,000 mph at the equator and therefore there must be a force generated by the slower moving fluid layer on top compared to the solid 1000 mph layer underneath it. Mountains are like rocks on a river bed if the rocks were moving faster than the water lol

 

eta: thanks for explaining it, CAPE

Fluid mechanics/dynamics is cool stuff. Fascinating.

Look up Karman vortex street. Vortex shedding occurs on all scales with high enough flow around an obstruction. There is even a flowmeter based on the principle.

Link to comment
Share on other sites

35 minutes ago, Bob Chill said:

The shortwave/ull is actually trackable. Lol. It crawls down the west coast starting a week out and gets picked up by the southern stream of split flow. It's kinda busy underneath the npac ridge. Who knows what flies around the big blue ball dropping down lol

There it is on the GEFS. Man what a nice look.

1671418800-L9atYF4yg9A.png

  • Like 22
Link to comment
Share on other sites

2 minutes ago, Rhino16 said:

Would it be better to visit the mountains in that scenario, or take a chance and stay here? I think I know the answer but just curious…

Mountains are going to cash in with upslope the next 10+ days in almost every scenario

  • Like 2
Link to comment
Share on other sites

8 minutes ago, Maestrobjwa said:

The Euro and CMC are showing the 19th/20th threat as quite suppressed...wondering if it's coming in too soon. Now we need the block to relax, lol (but it would've just gotten established...might be too soon)

Do you really want to be in the bullseye this far out? We're essentially 10 days out lmao, why are we worrying about its outcome

  • Like 5
Link to comment
Share on other sites

13 minutes ago, Maestrobjwa said:

Yeah you right...we'll see. We oughta know by like Wed or Thurs though. I do wonder if the block is gonna actually be too much for that

Even with the advertised block, I would worry more about Ocean warmth getting involved with a low tracking too close. Seen that many times since 2016.

  • Like 1
Link to comment
Share on other sites

30 minutes ago, Maestrobjwa said:

The Euro and CMC are showing the 19th/20th threat as quite suppressed...wondering if it's coming in too soon. Now we need the block to relax, lol (but it would've just gotten established...might be too soon)

Euro looks pretty ripe to me post D6. Didn’t come together, but active pattern with cold air.

  • Like 4
Link to comment
Share on other sites

Now that the guidance has resolved the bigger picture Synoptics of the evolution this week, and it makes much more sense given the lack of any antecedent cold, we can start to get a clearer picture of what could come after. 
 

As the primary from this week stalls and slowly dies to our north in Canada cold will finally slide east across the Conus. For a time the flow is likely to be progressive and suppressive. Not sure about that first wave around the 20th. That might be a slider. After that  it gets interesting Imo. A lobe of the TPV is going to slide south through a temporary weakness in the blocking and end up in Canada. But at the same time the wave breaking from the system this week and that TPV is going to pump the NAO ridge and the blocking strengthens again.
 

After that is when I think is our best shot.  The TPV stuck under blocking will provide ample cold source. The key will be exactly how that TPV is situated. Several ways to score. Waves look to continue to eject from the pac and one could run the boundary under the TPV. The big dog potential would be around the 23-27th if something from the NS rotates down around the TPV and phases. That’s risky though. If there happens to be a 50/50 at the right time that’s the setup for a big storm. No 50/50 and too much Atlantic ridge in front and it would be a cutter. Weaker boundary waves would be higher probabilities for frozen but lower high end potential. Just my 2 cents how I think this might play out. Most of what I described the key events happen soon enough that I feel reasonably confident in this general progression. 

  • Like 16
  • Thanks 1
Link to comment
Share on other sites

7 minutes ago, Scraff said:

Gotta love that 2009! LFG!!

6272FBDC-B18D-4844-98D2-8D7FDDA9E5BA.jpeg

It is a very similar look.  In 2009 eventually a piece of the TPV did drop in and phase while there was a 50/50 in the way to prevent a cutter. But keep in mind it took a while. We had a cutter and a sheared wave after that date before finally getting the win.  Great setup doesn’t mean “next wave is definitely a big snow”. Even in our best patterns we often need multiple chances before we get a hit. 

  • Like 4
Link to comment
Share on other sites

4 minutes ago, psuhoffman said:

It is a very similar look.  In 2009 eventually a piece of the TPV did drop in and phase while there was a 50/50 in the way to prevent a cutter. But keep in mind it took a while. We had a cutter and a sheared wave after that date before finally getting the win.  Great setup doesn’t mean “next wave is definitely a big snow”. Even in our best patterns we often need multiple chances before we get a hit. 

I've noticed that the data from CPC analogs apparently only goes through 2009. Do you or anyone in here know where can I find analogs from 2010 onwards?

Link to comment
Share on other sites

8 minutes ago, psuhoffman said:

It’s trending more negative day 10-15 than guidance showed it previously. Not more negative than the -4 stdv it is now. We don’t need the AO to be -4 to snow. 

Agreed,  that was my point. Certainly appears we are entering a long duration negative AO regime. This will also be the first December in many years where the robust snow cover extent in North America didn't go poof after December 20th. A healthy cryosphere, a good sign. 

 

 

  • Like 2
Link to comment
Share on other sites

15 minutes ago, Bob Chill said:

D10 setup isn't all that different than how we got snow in Dec/Jan 2013-14.  It's also a way to hit a little hot streak. Too progressive for a big storm but not a couple small ones lol

IIRC, that year we had the -EPO rocking, but also a super ++NAO much of the time as long as the pERleR VerTeX didn’t pay us a visit. So that could give us more space for storms to slow down.

  • Like 1
Link to comment
Share on other sites

17 minutes ago, Bob Chill said:

D10 setup on gfs/euro isn't all that different than how we got snow in Dec/Jan 2013-14.  It's also a way to hit a little hot streak. Too progressive for a big storm but not a couple small ones lol

With the -NAO/AO why is it progressive?  I thought those indices make it not progressive and allow storms to amplify and slowdown. 

  • Like 2
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...