December 16/17 Winter Event

[PhineasC]

After all these years, people still don’t recognize when psuhoffman goes into reverse psychology mode. LOL

[FXW176]

2 minutes ago, Ellinwood said:

No changes... gradient area near I-95 is boom or bust at this point. Leaning slightly toward bust near I-95, but this isn't worth micro-editing.

Thank you as always @Ellinwood. Your maps are seriously one of the very few I share with friends and fam. Apprec!

[WinterWxLuvr]

Also take a look at the precip maps at 42. Toggle between the 12z and 6z runs. You can see a pronounced counterclockwise turn. I think that’s significant if you’re hoping for a temp crash and a burst of snow on the backend

[aldie 22]

4 minutes ago, PhineasC said:

After all these years, people still don’t recognize when psuhoffman goes into reverse psychology mode. LOL

I swear I was about to write the same thing....."it's the debate coach in me" excuse is gonna come out next

[DDweatherman]

Just now, WinterWxLuvr said:

Also take a look at the precip maps at 42. Toggle between the 12z and 6z runs. You can see a pronounced counterclockwise turn. I think that’s significant if you’re hoping for a temp crash and a burst of snow on the backend

Although I am definitely rooting for that as part of the outcome, I'd favor a good slug/thump of WAA on the front end to lay a nice base of snow and get some good rates. That could also help keep the column cool if we do get the secondary snow from any wraparound. Keep watching those h7/h85 depictions...those closing off is part of our recipe to do well. 

[aldie 22]

2 minutes ago, WinterWxLuvr said:

Also take a look at the precip maps at 42. Toggle between the 12z and 6z runs. You can see a pronounced counterclockwise turn. I think that’s significant if you’re hoping for a temp crash and a burst of snow on the backend

his rebuttal to you is going to be 2 pages long and I swear i'm going to quote it 5 times

[Amped]

2 minutes ago, WinterWxLuvr said:

Also take a look at the precip maps at 42. Toggle between the 12z and 6z runs. You can see a pronounced counterclockwise turn. I think that’s significant if you’re hoping for a temp crash and a burst of snow on the backend

Last second trends always make an accurate forecast practically impossible. Now it's up to mets to gamble and extrapolate the  models even further NW cause the models are playing catch up and won't quite make it.

 

[baltosquid]

Here's what the HREF ensemble spits out through 12z Thursday.

[DDweatherman]

Just now, wxtrix said:

our upper air temps never go above freezing on that run so i don't think it's west.

Agreed trixie. I think in reality the surface reflection isn't indicative of where the true LP center is. Mesoscale differences aside, a more wound up system that does cause the mid levels to close off/stack for us might also be what is giving the double barrel look where we're seeing a low over the bay instead of over OC/right off the coast. 

[baltosquid]

And the weenie version of the same map...

I'm gonna pay attention to Frederick's totals to see if the HREF is picking up on the jackpot. No grades will be given but it will be fun to check.

[WinterWxLuvr]

3 minutes ago, baltosquid said:

And the weenie version of the same map...

I'm gonna pay attention to Frederick's totals to see if the HREF is picking up on the jackpot. No grades will be given but it will be fun to check.

I’m going with this one lol

[catoctin wx]

4 minutes ago, baltosquid said:

And the weenie version of the same map...

I'm gonna pay attention to Frederick's totals to see if the HREF is picking up on the jackpot. No grades will be given but it will be fun to check.

That jackpot appears to be right through Emmitsburg.  Well positioned for the win on this weenie map @North Balti Zen

[BTRWx's Thanks Giving]

5 minutes ago, baltosquid said:

And the weenie version of the same map...

I'm gonna pay attention to Frederick's totals to see if the HREF is picking up on the jackpot. No grades will be given but it will be fun to check.

What do you mean by weenie version? How are they different?

[North Balti Zen]

@catoctin wxWin. Snow, BBQ and my labrador retriever.  I would like this to work out.

[psuhoffman]

22 minutes ago, clskinsfan said:

psu what is causing the western shift of the track? Is it a more wound up system?

Death by a thousand paper cuts.  The high has trended SLIGHTLY NE of where it was days ago.  The confluence in the NE weakened some.  The 50/50 moves out slightly faster...and the storm slowed down 6-12 hours...increasing the spacing between the two and allowing for more ridging in front of it.  I was always bothered by how far west the upper level trough was going neutral and starting to lift, we needed all those other things to offset and they went the wrong way.  Some problems that I think the globals had a hard time seeing at range...that are now coming into focus (NAM saw it from jump) was the without a closed off mid and upper level circulation (ERS talked about this) there is nothing to stop the easterly flow north of the low from blasting way NW.  Add in all the warm water and that is shifting the boundary west...and the low track right with it.  I don't think there is any one thing to point to that did this...it was a lot of things that all went the wrong way...and that was partly why this was a slow bleed and not a sudden shift.  No one factor suddenly got a LOT worse...they all just degraded along the margins a little.  IMO what hurt us most was just a little too much spacing between the 50/50 combined with the trough digging in a little too far west then lifting instead of amplifying along the east coast.  The other factors like warm water and less confluence and shallow cold could have overcome that if they had all trended perfectly...but the warts in the overall synoptic setup required a lot else to go perfect...for a time it seemed like they all would.  

[catoctin wx]

1 minute ago, BTRWx's Thanks Giving said:

What do you mean by weenie version? How are they different?

Ensemble max vs. ensemble mean

[dailylurker]

Woohoo! Got an advisory! Yay flood watch lmao. I won't be laughing at the NAM anymore. 

[clskinsfan]

UKIE at the mouth of the bay at 36. But 540 line well west.

 

[DDweatherman]

Just now, psuhoffman said:

Death by a thousand paper cuts.  The high has trended SLIGHTLY NE of where it was days ago.  The confluence in the NE weakened some.  The 50/50 moves out slightly faster...and the storm slowed down 6-12 hours...increasing the spacing between the two and allowing for more ridging in front of it.  I was always bothered by how far west the upper level trough was going neutral and starting to lift, we needed all those other things to offset and they went the wrong way.  Some problems that I think the globals had a hard time seeing at range...that are now coming into focus (NAM saw it from jump) was the without a closed off mid and upper level circulation (ERS talked about this) there is nothing to stop the easterly flow north of the low from blasting way NW.  Add in all the warm water and that is shifting the boundary west...and the low track right with it.  I don't think there is any one thing to point to that did this...it was a lot of things that all went the wrong way...and that was partly why this was a slow bleed and not a sudden shift.  No one factor suddenly got a LOT worse...they all just degraded along the margins a little.  IMO what hurt us most was just a little too much spacing between the 50/50 combined with the trough digging in a little too far west then lifting instead of amplifying along the east coast.  The other factors like warm water and less confluence and shallow cold could have overcome that if they had all trended perfectly...but the warts in the overall synoptic setup required a lot else to go perfect...for a time it seemed like they all would.  

So, what do we look for now for some last minute respite? 

[BTRWx's Thanks Giving]

Just now, catoctin wx said:

Ensemble max vs. ensemble mean

Do ensemble max charts even belong here?

[catoctin wx]

3 minutes ago, BTRWx's Thanks Giving said:

Do ensemble max charts even belong here?

ha. Well that's a fair question.  Gotta keep the morale up or things will get ugly

[mattb65]

4 minutes ago, DDweatherman said:

So, what do we look for now for some last minute respite? 

Here's a good place to start 

 

[Deck Pic]

Final Call

[clskinsfan]

UKIE is gonna be a nice hit west of town. Looks a lot like the GFS actually.

[WinterWxLuvr]

1 minute ago, clskinsfan said:

UKIE is gonna be a nice hit west of town. Looks a lot like the GFS actually.

Pics or it never happened 

[baltosquid]

3 minutes ago, BTRWx's Thanks Giving said:

Do ensemble max charts even belong here?

Only dropping it in for the fun of it! The mean is of course what we should be looking at. Though some features are maybe easier to see in something like the max, like the frederick jackpot. There's already some better snowfall there in the mean to hint at better rates there but the max really highlights that at least one of the models in the blend likes that area. For what it's worth, the 00z run ALSO pegged northern Frederick for good totals through 00z Thursday, which is why I'm keen to see how that verifies. It's visible on both the mean and max.

[wxbeaz]

5 minutes ago, psuhoffman said:

Death by a thousand paper cuts.  The high has trended SLIGHTLY NE of where it was days ago.  The confluence in the NE weakened some.  The 50/50 moves out slightly faster...and the storm slowed down 6-12 hours...increasing the spacing between the two and allowing for more ridging in front of it.  I was always bothered by how far west the upper level trough was going neutral and starting to lift, we needed all those other things to offset and they went the wrong way.  Some problems that I think the globals had a hard time seeing at range...that are now coming into focus (NAM saw it from jump) was the without a closed off mid and upper level circulation (ERS talked about this) there is nothing to stop the easterly flow north of the low from blasting way NW.  Add in all the warm water and that is shifting the boundary west...and the low track right with it.  I don't think there is any one thing to point to that did this...it was a lot of things that all went the wrong way...and that was partly why this was a slow bleed and not a sudden shift.  No one factor suddenly got a LOT worse...they all just degraded along the margins a little.  IMO what hurt us most was just a little too much spacing between the 50/50 combined with the trough digging in a little too far west then lifting instead of amplifying along the east coast.  The other factors like warm water and less confluence and shallow cold could have overcome that if they had all trended perfectly...but the warts in the overall synoptic setup required a lot else to go perfect...for a time it seemed like they all would.  

you're analysis is always impeccable. are you saying this is a fail?

[clskinsfan]

Just now, WinterWxLuvr said:

Pics or it never happened 

[Amped]

Western shift is due to the following 3 things

1. The troff keeps trending, slower with higher heights ahead of it.   

2.  #1 is really bad when there is a high moving offshore.

3. The primary in the OV keeps trending stronger.  

 

 

[yoda]