January 22-23 Mid Atlantic Storm Thread #1 - No Banter

[Ian]

e7, dear lord. massacre.

[Bob Chill]

I do think it would be preferable to get the full transfer like the Euro has further south. I think that's a big part of the drier spot to the SW on the GFS. The Euro already has a well developed front end thump for those areas because of it. In that sense I think you have to hope the Euro is right just because it's a more proper HECSing if nothing else, but also because generally delayed is rarely the hope for in the snowstorm game. But if those are our bounds.. it could be a lot worse.

 

Totally agree there. Comparing earlier panels between the euro and gfs definitely shows a better lead in. I'm done analyzing the GFS anyways. It's not the preferred model and it's still to far out in time to dissect ops until they are stripped naked and wandering aimlessly down the street. 

 

If the euro holds its early stuff and then tracks OBX to 75 miles off of OC I'm going to frame the panels and wallpaper my house with them. 

[gymengineer]

The GEFS is the best one yet....

I counted 13 huge hits for DC. Only one member gives us nada.

Much more of them (16) have the maximum to the west or southwest of DC than to the north or northeast of DC. 

[nj2va]

15-16" snowfall mean for DC on the GEFS, basically in lockstep with the EPS.  

[Ian]

Weenie suicide watch on E7.

Sent from my iPhone using Tapatalk

e7 is like 7,500 miles east of the others. short bus.

[yoda]

GEFS and EPS means both locked in at around 15"

[IUsedToHateCold]

The thermal layer stuff is fascinating. I know the models have complex algorithms for figuring out how the low affects 850mb and surface temps, but I really want to understand the why and how of this more. I think (?) I get the basics, east and northeast winds on the top and west side of the low pump in moisture (originating from the Atlantic) at the upper levels which raises temps, creating a warm nose. Further distance from the LP reduces chances of being underneath the warm nose. 

 

Does the warm nose increase linearly with the strength of the low (lower pressure)? It seems like it would because of stronger winds. Would winds from the high pressure system interact with winds from the low pressure, suppressing or counteracting the warm nose?

 

In the 2/12/14 storm, east of 95 switched to sleet/rain with a low parked to the east of the Delmarva (which is 100+ miles away from my backyard). That low was 990MB (roughly). Assuming this is stronger, would it be safe to say that an even greater field of area would experience a warm nose if the low were to take the current GFS track? And that a lot of our area would experience the warm nose if it took the euro track? 

 

Not sure I buy the higher totals being advertised for those of us closer to the water. Seems iffy (?)

[nj2va]

Tight cluster over OBX.

 

[Midlo Snow Maker]

sorry if this has already been posted cips analogs hr 96 and hr 120

 

 

120

[ravensrule]

sorry if this has already been posted cips analogs hr 96 and hr 120

 

 

 

120

 

It has not. Thank you, good stuff.

[MN Transplant]

If midlo or someone could grab the CIPS analog list (I saw it in the NYC thread), that would be great. A bunch of the biggies are there.

[gymengineer]

The thermal layer stuff is fascinating. I know the models have complex algorithms for figuring out how the low affects 850mb and surface temps, but I really want to understand the why and how of this more. I think (?) I get the basics, east and northeast winds on the top and west side of the low pump in moisture (originating from the Atlantic) at the upper levels which raises temps, creating a warm nose. Further distance from the LP reduces chances of being underneath the warm nose. 

 

Does the warm nose increase linearly with the strength of the low (lower pressure)? It seems like it would because of stronger winds. Would winds from the high pressure system interact with winds from the low pressure, suppressing or counteracting the warm nose?

 

In the 2/12/14 storm, east of 95 switched to sleet/rain with a low parked to the east of the Delmarva (which is 100+ miles away from my backyard). That low was 990MB (roughly). Assuming this is stronger, would it be safe to say that an even greater field of area would experience a warm nose if the low were to take the current GFS track? And that a lot of our area would experience the warm nose if it took the euro track? 

 

Not sure I buy the higher totals being advertised for those of us closer to the water. Seems iffy (?)

It depends on more than the low position. Compare 2/12/14 to 2/11/83:

http://mp1.met.psu.edu/~fxg1/NARR/2014/us0213.php

http://mp1.met.psu.edu/~fxg1/NARR/1983/us0211.php

 

In 2/11/83, the low came up to the mouth of the Chesapeake Bay. But the position of the high pressure was different between the two. In 2/14, the high was scooting out to the east (check out 12Z) while in 2/83 it remained over the low. There are other factors too, but that's just one that makes a big difference. 

[yoda]

Also grabbed from the NYC thread:

 

 

Midlo grabbed the CIPS a few posts above mine... don't know if my attachment is NYC oriented or just CIPS oriented overall... some nice dates in the Top 10 there

[midatlanticweather]

This topic will come up time and again over teh next several days - http://blog.wdtinc.com/blog/rainfall-to-snow-ratios-how-are-they-calculated?utm_campaign=liquid%20to%20snow%20-DM&utm_medium=ALL&utm_source=

[IUsedToHateCold]

It depends on more than the low position. Compare 2/12/14 to 2/11/83:

http://mp1.met.psu.edu/~fxg1/NARR/2014/us0213.php

http://mp1.met.psu.edu/~fxg1/NARR/1983/us0211.php

 

In 2/11/83, the low came up to the mouth of the Chesapeake Bay. But the position of the high pressure was different between the two. In 2/14, the high was scooting out to the east (check out 12Z) while in 2/83 it remained over the low. There are other factors too, but that's just one that makes a big difference. 

 

That's very interesting. Thank you!

[Yeoman]

Any sign of the Euro para?

[Quasievil]

Any sign of the Euro para?

I think that starts running around 7ish.

[gymengineer]

That's very interesting. Thank you!

And again, it's not always useful to use generalities for determining the mixing. For instance, in 1/96, the warm nose was narrow and in the 600-700 mb layer. I think what some people forget based on their posts is that warm layer intrusion happened while the low was weak during the storm's "messy" phase. By the time the low started deepening more quickly near Norfolk, the warm layer for the cities was already mixed out. 

[clskinsfan]

Major models all look nearly identical across CONUS in the mid-levels. The 500mb track is basically the same to model to model. Kinda just seeing them spit out the various options in that environment. Could shift. Till it does... enjoy.

 

Agreed. The 500 track is really just about perfect for us on all the models. Thats really all you can ask for at this timeframe. The surface low is going to jump around some with a storm like this  anyways.

 

And I want to say there is really some excellent posting in here this evening. Great storm thread so far.

[WxMan1]

We are still far enough out to fail if shooting for a HECS in anyone's backyard for sure. But... I think we are pretty locked in at the mid levels given what we see across modeling.

 

I think this is something already brought up, especially with respect to the Feb 5-6 2010 system which crossed Elizabeth City NC and went northeast (passing east of ORF)...

 

If we can get more of a wsw-ene low track (and thus wsw-ene distribution of heavier snowfall), the odds of more serious mixing along the I-95 corridor between DC and Balt will be much lower than if the low has any more of a northward component.  Any track over ORF and into the mouth of Ches Bay will most likely lead to at least some mixing...if not dryslot...a-la Feb 12-13 2014.  Now, the *good* news with more of a SW-NE low track...while the odds of a mix/transition and/or dry-slotting is higher...is that you'd get a better chance to get another 2-4+ from the backside deformation band.