December Med/Long Range Discussion

[poolz1]

Heck of a cold look to the LR GEFS.  Members have been hinting at some accumulations during day 11-15 for the last several runs....not an overly strong signal but possibly the 12/10 - 12/15 range could be our first window?  One thing for sure is Canada is going from a furnace to the freezer...good sign.

[dallen7908]

A bit off topic but a few years ago I saw a poster from a student at Lyndon State (might have the college wrong) that showed a strong positive correlation between Vermont snows and the phase of the NAO, i.e, a positive NAO was associated with zonal flow and above average snow totals. A different world up there. 

I would like something to track between XMAS and New Year's. I can't remember the last time I tracked anything then (don't bring up 2010, although I did relatively well 0.5"). 

The average high at DCA (BWI) falls to 50 on December 4th (1st). 

 

 

 

[Eskimo Joe]

5 hours ago, Kmlwx said:

This is shocking coming from you. I'm tempted to ask if somebody hacked your account. You would meh a 5-8 incher into oblivion on any other day other than Xmas. 

A region wide warning criteria event on Christmas is historic in these parts, plus it's Christmas snow which is a multiplier of a factor of four compared to non-Christmas snow.

[Windman18]

Looks like December 10th could be the start of a nice window for snow. Plenty cold

[Amped]

 

33 minutes ago, Windman18 said:

Looks like December 10th could be the start of a nice window for snow. Plenty cold

December 8th, winter is always 10 days away.

[showmethesnow]

00Z Ensembles are in two different camps in regards to a closed low and associated trough at 500 mb in the baja/mexico region around day 5. GEFS and the GEM lock it there and eventually wash it out while the EPS is progressive and interacts with low pressure in the gulf to pull a storm up into the lakes and northeast.  Downstream implications (day 10-15) looks as if the EPS solution has a better look for snow chances compared to the GEFS, as it brings extended troughiness and lower height anomalies to the eastern 3rd of the US. GEM only goes to day 10 but the look isn't good as it builds heights in the east.

[Kmlwx]

12 hours ago, Eskimo Joe said:

A region wide warning criteria event on Christmas is historic in these parts, plus it's Christmas snow which is a multiplier of a factor of four compared to non-Christmas snow.

It better not melt for 2 weeks then! 

[mitchnick]

4 hours ago, showmethesnow said:

00Z Ensembles are in two different camps in regards to a closed low and associated trough at 500 mb in the baja/mexico region around day 5. GEFS and the GEM lock it there and eventually wash it out while the EPS is progressive and interacts with low pressure in the gulf to pull a storm up into the lakes and northeast.  Downstream implications (day 10-15) looks as if the EPS solution has a better look for snow chances compared to the GEFS, as it brings extended troughiness and lower height anomalies to the eastern 3rd of the US. GEM only goes to day 10 but the look isn't good as it builds heights in the east.

The bias of the "old" Euro was to keep those closed lows hanging out too long in the SW. Nice test for the updated version.

[WinterWxLuvr]

What's the Euro showing for day 6?  Low in Alabama and cold wedge down the apps?

[mitchnick]

6 minutes ago, WinterWxLuvr said:

What's the Euro showing for day 6?  Low in Alabama and cold wedge down the apps?

cutter

[Bob Chill]

10 minutes ago, WinterWxLuvr said:

What's the Euro showing for day 6?  Low in Alabama and cold wedge down the apps?

I posted about it in the Nov obs thread. CAD leading in. It's one of the classic front end looks for your hood but it's too early in the season so temps are no good.  Verbatim your area gets around .20+/- qpf as snow but surface temps are crappy. 

Last night's euro ens had a little bit of support for you area as well. Worth watching i suppose. 

[Bob Chill]

Interestingly...about 1/3rd of the euro ens members now bring some snow to I95 and west with the 4/5th storm. Pretty big jump from 0z. Wnwxluvr's chances of his first event have increased quite a bit...

[WinterWxLuvr]

1 hour ago, mitchnick said:

cutter

 

56 minutes ago, Bob Chill said:

I posted about it in the Nov obs thread. CAD leading in. It's one of the classic front end looks for your hood but it's too early in the season so temps are no good.  Verbatim your area gets around .20+/- qpf as snow but surface temps are crappy. 

Last night's euro ens had a little bit of support for you area as well. Worth watching i suppose. 

It's definitely worth watching (supposing that you can trust a day 6-7 forecast).  It certainly isn't a typical cutter (west central Alabama almost straight north to Toledo).  A little flatter h5 and it might not cut at all.  High pressure north of lake Huron on day 6.  Definitely worth watching.

[mappy]

was just looking at that, def some nice CAD for the Winchester area. Not so much for the rest of us. 

[WinterWxLuvr]

Just now, Bob Chill said:

Interestingly...about 1/3rd of the euro ens members now bring some snow to I95 and west with the 4/5th storm. Pretty big jump from 0z. Wnwxluvr's chances of his first event have increased quite a bit...

Just posted.  The setup that I can see on IWM is one that could certainly be interesting if nothing else.

[WinterWxLuvr]

Just now, mappy said:

was just looking at that, def some nice CAD for the Winchester area. Not so much for the rest of us. 

Get that high a bit stronger, 4 mb or so and move it to about Montreal and it becomes interesting for anyone above the coastal plain.

Good to see we are starting to get discussion pieces. 

[mappy]

Just now, WinterWxLuvr said:

Get that high a bit stronger, 4 mb or so and move it to about Montreal and it becomes interesting for anyone above the coastal plain.

Good to see we are starting to get discussion pieces. 

Definitely! Plus, it's the weekend, and 12/5 (ish). 

Book it.  

[Bob Chill]

Just now, WinterWxLuvr said:

Just posted.  The setup that I can see on IWM is one that could certainly be interesting if nothing else.

It really is a shame that we aren't 3 weeks down the line into Dec. It's a classic front ender setup for our area. Can't draw it up any better. Just don't have a stout antecedent airmass like we would later in the month. I don't have meteograms yet but looking at the panels the QPF is around 1" for the storm. 

[psuhoffman]

3 minutes ago, mappy said:

was just looking at that, def some nice CAD for the Winchester area. Not so much for the rest of us. 

Over the years I've observed that we don't typically do as well from CAD setups as places to our southwest.  My best guess is the topography there helps hold in the cold and enhance qpf and that once that wedge is busted the warm layer tends to race north pretty fast so often they get a good thump while we're north of the best lift then when the precip does move north so does the warm air. We do better in almost every other setup though so I'm not complaining at all. 

[mappy]

2 minutes ago, Bob Chill said:

It really is a shame that we aren't 3 weeks down the line into Dec. It's a classic front ender setup for our area. Can't draw it up any better. Just don't have a stout antecedent airmass like we would later in the month. I don't have meteograms yet but looking at the panels the QPF is around 1" for the storm. 

On the euro? probably closer to 2", at least for Winchester. From 12z Sun to 00z Tue 

[mappy]

1 minute ago, psuhoffman said:

Over the years I've observed that we don't typically do as well from CAD setups as places to our southwest.  My best guess is the topography there helps hold in the cold and enhance qpf and that once that wedge is busted the warm layer tends to race north pretty fast so often they get a good thump while we're north of the best lift then when the precip does move north so does the warm air. We do better in almost every other setup though so I'm not complaining at all. 

Yeah, I don't recall a really good CAD event since I moved north. I mean, we've had them, but they are quick, the cold erodes away sooner than I had hoped. 

I don't recall the setup for the Feb '14 ice storm... 

[Bob Chill]

2 minutes ago, mappy said:

On the euro? probably closer to 2", at least for Winchester. From 12z Sun to 00z Tue 

I was looking at the ens mean panels. Pretty solid signal for a decent qpf maker. Just need to work on speeding up the precip and stronger hp to the north. hee hee

[mappy]

3 minutes ago, Bob Chill said:

I was looking at the ens mean panels. Pretty solid signal for a decent qpf maker. Just need to work on speeding up the precip and stronger hp to the north. hee hee

ahhhh -- okay. i was just looking at the main run panels.  

[frd]

Any wagers on what the Euro Weeklies will look like when they are released this evening ?

Could be intriguing, as the end of the Euro run today shows some interesting features up North. 

[Bob Chill]

Pretty sweet eps run. Impressive cold shot on the means from the 10th onward. Aleutian ridge pokes all the way to the pole and the squeeze is on with ridging pressing from europe/iceland/greenland towards the end of the run. If that general idea is stable then we could very well be in for a cold december. All I know is what is being advertised is definitely nothing like what we've seen going into Dec for a long time. 

[Bob Chill]

6 minutes ago, frd said:

Any wagers on what the Euro Weeklies will look like when they are released this evening ?

Could be intriguing, as the end of the Euro run today shows some interesting features up North. 

The weeklies will roll last night's 0z ens run forward. My guess? It's going to look pretty good. At least for temps anyways. I can envision the -nao strengthening while the aluetian ridge remains in place. We can do just fine with a -pna with low height anomalies centered near 50/50. 

[Round Hill WX]

3 minutes ago, Bob Chill said:

Pretty sweet eps run. Impressive cold shot on the means from the 10th onward. Aleutian ridge pokes all the way to the pole and the squeeze is on with ridging pressing from europe/iceland/greenland towards the end of the run. If that general idea is stable then we could very well be in for a cold december. All I know is what is being advertised is definitely nothing like what we've seen going into Dec for a long time. 

Quite cold EPS run for sure. 

[CAPE]

34 minutes ago, Bob Chill said:

Pretty sweet eps run. Impressive cold shot on the means from the 10th onward. Aleutian ridge pokes all the way to the pole and the squeeze is on with ridging pressing from europe/iceland/greenland towards the end of the run. If that general idea is stable then we could very well be in for a cold december. All I know is what is being advertised is definitely nothing like what we've seen going into Dec for a long time. 

You said it- nothing like we have seen for a December pattern recently. Great looking run. 

[frd]

49 minutes ago, Bob Chill said:

The weeklies will roll last night's 0z ens run forward. My guess? It's going to look pretty good. At least for temps anyways. I can envision the -nao strengthening while the aluetian ridge remains in place. We can do just fine with a -pna with low height anomalies centered near 50/50. 

Thanks Bob. 

We might tap into the extreme arctic air over Alaska, ( minus 68 degrees F, thats nuts !!!  )   as well, possibly in time . I imagine the air mass over Alaska has origins to Siberia, via somewhat cross-polar flow    

 

[WinterWxLuvr]

1 hour ago, psuhoffman said:

Over the years I've observed that we don't typically do as well from CAD setups as places to our southwest.  My best guess is the topography there helps hold in the cold and enhance qpf and that once that wedge is busted the warm layer tends to race north pretty fast so often they get a good thump while we're north of the best lift then when the precip does move north so does the warm air. We do better in almost every other setup though so I'm not complaining at all. 

This is mostly true. The warm air tends to have an easier time racing north to the east of the BR.

The Dec 26 2013 storm is a good example.  While most saw some snow that day, places to the east warmed quickly.  Balt made it to almost 50 while we never made it to freezing before the cold front raced in and dropped everyone's temps.