December 16/17 Winter Event

[DDweatherman]

1 minute ago, clskinsfan said:

Can we see a 0z for comparison? Almost time for the Euro to pull the ole Lucy. 

[Paleocene]

Ah, the low at the classic Philadelphia benchmark. Thanks UKMET

[clskinsfan]

2 minutes ago, DDweatherman said:

Can we see a 0z for comparison? Almost time for the Euro to pull the ole Lucy. 

[mattie g]

On 12/14/2020 at 10:50 AM, mattie g said:

Let's just run this thing up the Shenandoah Valley and so we can all be miserable together!

[WinterWxLuvr]

5 minutes ago, clskinsfan said:

There’s that ccw turn showing again

[clskinsfan]

UK tracks the low from the mouth of the bay to just south of Philly to due east off the coast of central Jersey. Wild man. 

[DDweatherman]

1 minute ago, clskinsfan said:

UK tracks the low from the mouth of the bay to just south of Philly to due east of the coast of central Jersey. Wild man. 

Because it heads due east from Philly, the mid levels would crash and cause us to go back to snow if it happened exactly as depicted on the UK. 

[clskinsfan]

1 minute ago, DDweatherman said:

Because it heads due east from Philly, the mid levels would crash and cause us to go back to snow if it happened exactly as depicted on the UK. 

Yeah. You can see it in the 850 wind charts. 

[NorthArlington101]

I fully recognize the ensembles are not that relevant at this point, but it is odd to see them well east of the OP.

[DDweatherman]

On mobile, but about half the GEFS members take the low SE of the opp, less than a handful west. Too close in to take ground truth verbatim, but hopefully the east side of that envelope prevails. 

[psuhoffman]

1 hour ago, WinterWxLuvr said:

You have forgotten more weather than I’ll ever know but I have to say that I don’t agree with this.  It seems everyone just looks at the letters L and H but never at the isobars. At 36 the gfs has the lowest pressure over Norfolk. Same as previous run. At 42 the lowest pressures are well off shore where as at 6z they were right over Ocean City. Just my take.

This is what I saw 

 

[DDweatherman]

Just now, NorthArlington101 said:

I fully recognize the ensembles are not that relevant at this point, but it is odd to see them well east of the OP.

Literally posted at the exact same time on this. That can't hurt us to see regardless of range/res. 

[snowmagnet]

It seems really quiet on here all of a sudden. I guess we are all on pins and needs waiting for the almighty Euro....

[gisman]

Ok, I was planning for a family chase to decent snows for a couple nights, but now I am confused whether there would be much of a payoff anymore. Was thinking Rocky Gap state park for its pleasant surroundings. Worth it?

[psuhoffman]

49 minutes ago, wxtrix said:

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

Surface track was west...mid level results were better due to a better close off of the mid and upper level circulations earlier.  That would lead to a tighter wound system...which is good if you have an inside track.  There was a lot to like in the 12z GFS I was just pointing out that the larger trend of the track shifting west did not halt, that was the bad.  

[DDweatherman]

Just now, psuhoffman said:

Surface track was west...mid level results were better due to a better close off of the mid and upper level circulations earlier.  That would lead to a tighter wound system...which is good if you have an inside track.  There was a lot to like in the 12z GFS I was just pointing out that the larger trend of the track shifting west did not halt, that was the bad.  

I'm mobile, do you have access to the ML depictions on the Euro to see if it has the ML/UL circulations closed off and thats part of its reason on better thermals? 

[WinterWxLuvr]

6 minutes ago, psuhoffman said:

This is what I saw 

 

And I would have agreed if I saw those maps. I was going off of TT

[clskinsfan]

My brain is fried so I might be wrong. But I think WeatherUS has the hi rez Euro out already for 12Z. If it is the 12Z run the Euro will hold for west of town. So hard to see anything on that site. 

[winterymix]

HREF is sleet-o-mania.     Some of our best storms have suffered from mid-storm sleet-poisoning.

 

https://www.spc.noaa.gov/exper/href/?model=href&product=qpf_001h_mean_ptype&sector=conus

[Amped]

At least we still have the RGEM 850mb wraparound mesobomb to track.

 

 

 

[BTRWx's Thanks Giving]

The high on the euro initialized due north of Pittsburgh and due east of Minneapolis fwiw.

[BTRWx's Thanks Giving]

That high is just moving too fast.

[jayyy]

We’re not going to know where this is headed until the storm is here. Models have virtually zero agreement on how to handle the high to the NE, the primary in the Ohio valley, and in turn, the SLP / 850 low track. Just the slightest over amplification or under amplification of the primary in the OV throws the entire storm into limbo. 
 

Yes, this often doesn’t end well... but the overwhelming majority of ensembles look much better than the OP with the location of the SLP. The mouth of the bay versus 50 miles offshore makes or breaks the entire storm for the eastern half of the cwa 

[MillvilleWx]

43 minutes ago, yoda said:

 

 

I hate to say it, but that is an unbelievably good catch by Eric. I’ve spent a lot of time focusing on model disco at both the synoptic and mesoscale the last several days, but at a regional parsing, and not at full broad scale look at the impending 5H pattern. Discernible differences like that can make or break a forecast. Those s/w progressions, especially one as small and later developing can have major downstream implications. PSU did a fantastic job outlining the “Death by a 1000 cuts” mantra. It doesn’t take one big thing to ruin a forecast, but small changes in both a synoptic and mesoscale sense can cause shifts in setups like this. High further NE and more western trek of an SLP will cause a large u-vector anomaly of the wind field, allowing the low-level easterlies to protrude way beyond the scope of where we were thinking 24 hrs ago. I’m gonna have to adjust my totals most likely due to the current state of guidance. I do see the 81 crew still doing the best here. HREF is very interesting to say the least, so I’ll have to dig more into that. It’s a phenomenal tool to use for situations like this, for ZR events, and especially for severe. Absolutely good bookmark.

 

I’m really tired. My neighbor set off a car alarm outside and it woke me up a bit earlier than normal for the PM. I’m heading back to bed. I hope my previous discos can sustain merit with the new trends, and don’t sway people to take my posts with a grain salt. I was just reporting my thoughts based on the model trends at hand. I wish I wasn’t on mids so I could delve more into the nitty gritty.

Edit: I had to switch to the PC and post this since Tapatalk absolutely butchered this post. Sorry for the repost.

[nj2va]

It looks like the low tracks west of the Bay through the Northern Neck to just east of Baltimore over the Bay.  by tomorrow, it’ll be over Fairfax.

[NorthArlington101]

EURO went even more west. Would definitely an outlier in its 6z ensembles, but not sure that matters. 

Still get 2" from the initial thump, even in the city. Better measure it before the rain begins to really ramp up.

[Deck Pic]

Next (For DC)....If you're west enough it is a pretty sound thumping...better than 6z

[NorthArlington101]

[jayyy]

1 minute ago, NorthArlington101 said:

EURO went even more east. Would definitely an outlier in its 6z ensembles, but not sure that matters. 

Still get 2" from the initial thump, even in the city. Better measure it before the rain begins to really ramp up.

Euro went East or west?

[AdamHLG]

4 minutes ago, jayyy said:

We’re not going to know where this is headed...

I hate to say it but deep down I think we all know where this is headed.  We just don't want to accept it.