The Ledge Storm 19-20 Feb

[baltosquid]

To my untrained eye, ICON h5 looks better but the surface pretty much looks the same

[Prestige Worldwide]

1 minute ago, CAPE said:

Nice disco here from LWX-

By the middle of the week, attention will turn to a potential winter storm approaching from the south and west. Recent trends have been for more separation between a southern stream disturbance (currently located off the Pacific Northwest Coast), and a northern stream disturbance (primarily composed of a shortwave currently moving from east to west along the northern periphery of an upper low currently centered over Manitoba and Saskatchewan). Greater spacing between these features would likely result in less interaction, and later phasing between these two disturbances, leading to a more southern storm track. This trend toward a more suppressed, southern track system started yesterday, continued with the 00z runs last night, and is even more prevalent within incoming 12z guidance. This trend toward a more southern track is leading to a trend down in snowfall totals across much of the area. While it still appears likely that most of the area will see at least some snowfall, a scenario where the northern half of the forecast area sees very little snowfall (nearly all in association with the northern stream system) is a distinct possibility now. That isn`t to say that the threat for a larger storm has gone away, it`s just that probabilities for that occurring have decreased greatly. At the moment, it appears as though southern Maryland currently stands the greatest chance for higher snowfall totals, as they`d be located closer to the southern storm track and eventual deepening coastal low. While the trend has been downward with snowfall totals, that doesn`t mean that there can`t be further shifts in either direction as we move closer to the event. The pattern across North America, as well as the North Pacific and North Atlantic is very complex at the moment, with numerous interactions between different disturbances yet to occur. This lends itself to some lingering uncertainty. Systems with lots of convection in the southern stream (as this one will) also commonly trend northward at short lead times. The upper level pattern to our northeast at the time of the system will likely be very blocked, so that potential for a northward shift back is somewhat limited, but still exists. So while the clear trend at the moment is very much toward a more southern track and lower snow totals, there is still time for things to change.

Systems with lots of convection in the southern stream (as this one will) also commonly trend northward at short lead times. - this is the nugget from that discussion imho 

[baltosquid]

Okay by 84 the low has definitely responded to the h5 and is closer in to the coast, slightly more expansive precip but not by much

[TSSN+]

Rgem is a big nada for anyone north of southern Md 

[Silver Meteor]

9 minutes ago, BristowWx said:

So the multi million dollar PS5 models are confused but the IntelliVision 1983 model has the right idea.   I’m good with this 

Oh boy does that bring back memories. Yes, I had an IntelliVision and I loved it. It was the best gaming machine of its time. 

[Wetbulbs88]

2 minutes ago, CAPE said:

Nice disco here from LWX-

By the middle of the week, attention will turn to a potential winter storm approaching from the south and west. Recent trends have been for more separation between a southern stream disturbance (currently located off the Pacific Northwest Coast), and a northern stream disturbance (primarily composed of a shortwave currently moving from east to west along the northern periphery of an upper low currently centered over Manitoba and Saskatchewan). Greater spacing between these features would likely result in less interaction, and later phasing between these two disturbances, leading to a more southern storm track. This trend toward a more suppressed, southern track system started yesterday, continued with the 00z runs last night, and is even more prevalent within incoming 12z guidance. This trend toward a more southern track is leading to a trend down in snowfall totals across much of the area. While it still appears likely that most of the area will see at least some snowfall, a scenario where the northern half of the forecast area sees very little snowfall (nearly all in association with the northern stream system) is a distinct possibility now. That isn`t to say that the threat for a larger storm has gone away, it`s just that probabilities for that occurring have decreased greatly. At the moment, it appears as though southern Maryland currently stands the greatest chance for higher snowfall totals, as they`d be located closer to the southern storm track and eventual deepening coastal low. While the trend has been downward with snowfall totals, that doesn`t mean that there can`t be further shifts in either direction as we move closer to the event. The pattern across North America, as well as the North Pacific and North Atlantic is very complex at the moment, with numerous interactions between different disturbances yet to occur. This lends itself to some lingering uncertainty. Systems with lots of convection in the southern stream (as this one will) also commonly trend northward at short lead times. The upper level pattern to our northeast at the time of the system will likely be very blocked, so that potential for a northward shift back is somewhat limited, but still exists. So while the clear trend at the moment is very much toward a more southern track and lower snow totals, there is still time for things to change.

So we weren’t off when thinking they could be chasing convection after all. 
 

what a ride so far. 

[psuhoffman]

31 minutes ago, BTRWx's Thanks Giving said:

Stop ignoring bad outcomes!

If we did that with posts the threads would be a lot less pages 

[MillvilleWx]

Just now, Prestige Worldwide said:

Systems with lots of convection in the southern stream (as this one will) also commonly trend northward at short lead times. - this is the nugget from that discussion imho 

All about latent heat release and general feedback. This type of storm is going to have some shifts up until 24 hrs out, me thinks 

[BristowWx]

1 minute ago, deer said:

Newb question, why does the NAM show the precip field W-E while the globals mostly show SW-NE?

No questions now…you are getting shellacked with a foot of snow…just go with it. 

[LP08]

Dang…ICON was a pretty good step forward at H5 and almost capture.  

[TSSN+]

Icon is worlds better

12z vs 18z

 

[SomeguyfromTakomaPark]

ICON is better than its 12z run.  More precip up to us.

[ers-wxman1]

We all got caught in the day 5-7 model fantasy. Potential is still there for warning level snows for all of the sub forum, but the phased nor’easter solution is least likely given the upper level synoptic pattern that is evolving. Need strong ridge over the west and the 500/700/850 low to be closed and tracking to the south of DC with phasing to get a 1-2 foot + event here. I think this scenario is just about off the table. What is more conducive is a 4-8 type of event with a boom scenario to 12 for those that get under better forcing likely east given a low deepening offshore. Bad press/backyard Mets put this HECS wording out there and the public is going halfway nuts with degreed Mets trying to walk them off the edge. 

[StormyClearweather]

It's flopping around like a fish out of water, but this was a good flop (relatively) so

[Scraff]

Fuck it. Who’s pre-gaming the GooFus comeback!? Let’s get this done!! 

[Warm Nose]

24 minutes ago, psuhoffman said:

Ok ya it’s the NAM. I wish it was annything else. But it’s doing what I said the mid and upper level pattern should look like at the surface. Focusing more on the wave among the arctic front which pulls everything north further east. 

Images from my post last night about what changes I expected to see.  Now if we can get everything else to come around maybe.  Can’t believe I’m on a team with JB and the NAM. Shoot me now. 

 

[TSSN+]

Total 12z vs 18z

 

[baltosquid]

More h5 interaction but pretty late in the game. Need it to happen faster, then we'd be talking

[Silver Meteor]

14 minutes ago, adelphi_sky said:

The fact that the IntelliVision still turns on is a nod to its build quality. Hehe


.

It was made by Mattel. I was so impressed with it I bought stock in the company then later sold it for a good profit. 

[IronTy]

I'm gonna ride atmospheric memory for this storm.  SoMD has been jack all season and will do so again which should be good for the rest of the forum as well. 

[adelphi_sky]

ICON is better than its 12z run.  More precip up to us.

Please be the start of a trend!


.

[Ralph Wiggum]

7 minutes ago, deer said:

Newb question, why does the NAM show the precip field W-E while the globals mostly show SW-NE?

If the waa if as far N as the nam depicts even  before the pivot, look out

[Maestrobjwa]

2 minutes ago, IronTy said:

I'm gonna ride atmospheric memory for this storm.  SoMD has been jack all season and will do so again which should be good for the rest of the forum as well. 

Wait how would that be good for the rest of the forum? Lol If ya go with that that would means central and n. MD would be, well ya know...

[jewell2188]

Pulling for strings lmao

[Scraff]

1 minute ago, Maestrobjwa said:

Wait how would that be good for the rest of the forum? Lol If ya go with that that would means central and n. MD would be, well ya know...

You would maybe get 5”. But not 6. 

[IronTy]

Just now, Maestrobjwa said:

Wait how would that be good for the rest of the forum? Lol If ya go with that that would means central and n. MD would get screwed again...

Just because you're not jack doesn't mean you can't get good snows.  A NW jog to put SoMD at jack would also move the heavier snows up though the DC corridor. 

[AlexD1990]

Just now, IronTy said:

Just because you're not jack doesn't mean you can't get good snows.  A NW jog to put SoMD at jack would also move the heavier snows up though the DC corridor. 

It's also clear that the eventual evolution of this system is highly dependent on delicate interactions at range. Small changes early on can have big implications for sensible ex down the road. It's been interesting to track today.

[SomeguyfromTakomaPark]

6 minutes ago, TSSN+ said:

Total 12z vs 18z

 

50 mile shift to get a foot of snow to DC with 100 hours to go.  We can do it.

[Ralph Wiggum]

7 minutes ago, Scraff said:

Fuck it. Who’s pre-gaming the GooFus comeback!? Let’s get this done!! 

Is that a dipa with simcoe hops? Yummmmmm

[adelphi_sky]

50 mile shift to get a foot of snow to DC with 100 hours to go.  We can do it.

Damn straight.


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