March Med/Long Range Disco

[WinterWxLuvr]

I_nw_g1_EST_2013030112_120.png

 

today's CMC

I'll take that.  Damn near perfect.

[WinterWxLuvr]

GEFS is about 200 miles farther south at 132 and a bit farther offshore.  That's still pretty reasonable concurrence at D5.  A Euro ensemble/GFS ensemble blend is probably the safe forecast right now and that still is probably a good one for us in regards to streak-breaking.  

 

Thing about that is the move that it made.  Compare that to the same time from 0z.  Big move.

[Bob Chill]

First non-snow sounding I can find @ dca is @ 144. Which doesn't matter anymore of course. 

 

[Ian]

March 1958?  or did you consider that multiple events?

 

I have 4.8" for that one.

[MN Transplant]

First non-snow sounding I can find @ dca is @ 144. Which doesn't matter anymore of course. 

 

gfs144.JPG

 

The GFS soundings are good. 

 

The GGEM is super-wet.  It isn't like we shouldn't talk about other models, but we can give them the appropriate weight.

[psuhoffman]

GGEM for DC would be 6-10" of snow, followed by 6 hours of mix, then another 4-8" on the backside.  I know that would just be aweful.  For places from IAD to FDK to Westminster it would be 20" plus. 

[psuhoffman]

It looks like a snow to rain to heavy snow event literally.  120 is snow... 132 would probably be rain with that position for us... but then as the low gets captured by the h5 it stalls and moves slowly east bringing the snow back east with it

I wrote my interpretation of what it shows for DC...looking at the temp profiles a warm layer wraps in for about 6 hours but it gets cut off really fast as the low occludes then slides east.  Huge front and back end dump though.  All snow west of a line from IAD to Reisterstown

[Bob Chill]

I think I like reds better than purples. Better shock factor:

 

 

 

[tcutter]

GGEM for DC would be 6-10" of snow, followed by 6 hours of mix, then another 4-8" on the backside.  I know that would just be aweful.  For places from IAD to FDK to Westminster it would be 20" plus. 

 

 

no matter where i lived.....i would take that any day and twice on sunday

[WxUSAF]

Can't ignore the trend either

 

 

Thing about that is the move that it made.  Compare that to the same time from 0z.  Big move.

Yeah, it moved quite a bit closer to shore (~100 miles) and maybe 50-75 miles north.  

 

For phasing situations, the coarser resolution of the ensembles will not handle it as well as the higher resolution Op.  Ian has said the same thing by saying the Euro handles phasing better than the GFS.  This doesn't mean that the Op is correct and I would not discount the GEFS, but something to keep in mind.  

[mitchnick]

GGEM for DC would be 6-10" of snow, followed by 6 hours of mix, then another 4-8" on the backside.  I know that would just be aweful.  For places from IAD to FDK to Westminster it would be 20" plus. 

I thought we weren't supposed to talk about soundings at 5 days?  

hey, this is what I've been waiting for

[MN Transplant]

Post March 5th events at IAD >6"

 

3/9/76 - 6.4"

3/13-14/93 - 14.1"

3/9/99 - 8.9"

 

Actually thought the list might be longer. 

[psuhoffman]

I thought we weren't supposed to talk about soundings at 5 days?  

hey, this is what I've been waiting for

I have never been one to say we shouldnt talk about the details of model runs, as long as we understand its just for fun and to analyze and learn and not to take as an actual forecast, its fine with me.  But I guess my point still remains that worrying about a 2-3 degree problem with the boundary layer on the euro (known to have a warm bias at the surface) from 5 days out is a little bit too much. 

[NOVAForecaster]

The really good agreement considering we're still at 5 days out is a very good sign for this storm.

[mitchnick]

I have never been one to say we shouldnt talk about the details of model runs, as long as we understand its just for fun and to analyze and learn and not to take as an actual forecast, its fine with me.  But I guess my point still remains that worrying about a 2-3 degree problem with the boundary layer on the euro (known to have a warm bias at the surface) from 5 days out is a little bit too much. 

I guess we'll just have to respectfully disagree

I'm just a firm believer that we should take the models as they are since the entire column has an effect on the storm's nature, location, intensity, etc.

that's not to say that future runs won't change because we all know they will, but I think when discussing model runs we take the facts (so to speak) as they are spit out

[Bob Chill]

The really good agreement considering we're still at 5 days out is a very good sign for this storm.

 

It's just been so long in our yards it's hard to remember that the big ones are usually sniffed and locked pretty early on. This one is no different. Big storm possibility was locked in yesterday and now we get to play the mountain high / valley low game because the details won't be done for days. I suppose it's relatively safe to say that someone along the ec will experience a high impact event. We can only scope and hope it's us and have some fun while it lasts. 

[Quasievil]

It's just been so long in our yards it's hard to remember that the big ones are usually sniffed and locked pretty early on. This one is no different. Big storm possibility was locked in yesterday and now we get to play the mountain high / valley low game because the details won't be done for days. I suppose it's relatively safe to say that someone along the ec will experience a high impact event. We can only scope and hope it's us and have some fun while it lasts. 

A great conversation would be to discuss what could go wrong at this point and not simply to be Debbie Downers. My assumption is the GGEM's solution is based on an earlier phase from the GFS run. Right?

[Ian]

I wonder if Accu realizes Ash Wednesday gave DC 4" of snow. I mean that would be awesome and I know it hammered higher elevation but their press release calls for a potential major blizzard in the cities.

[Heisy]

Like Ji said, the 500mb on these model runs is absolute porn. The best part for you guys is the way it phases warm air would be sent into NE while Philly to DC gets clocked. 

[psuhoffman]

A great conversation would be to discuss what could go wrong at this point and not simply to be Debbie Downers. My assumption is the GGEM's solution is based on an earlier phase from the GFS run. Right?

I think the general evolution of the system is understood by the guidance at this point.  The 3 possible "screw jobs" we could get would be

1.  A late phase solution where it all comes together 6 hours too late for us and we watch NJ northeast get nailed (my biggest fear)

2.  The trend of an earlier phase continues and actually ends up cutting this inland (unlikely IMHO right now given the setup)

3.  The whole trough ends up further north then guidance and the storm simply tracks too far north for us (second biggest concern)

[Bob Chill]

A great conversation would be to discuss what could go wrong at this point and not simply to be Debbie Downers. My assumption is the GGEM's solution is based on an earlier phase from the GFS run. Right?

 

It's a pretty long conversation to be honest. Late phase would be very dicey. Too early could be a disaster. Further east track..ouch..

 

There's plenty to go wrong. As the suites come out it's probably best to just focus on the vort track, trough axis, and piece of energy over the gl's.

 

One big thing in our favor is the block and slow movement. Opens the door to have a better window of "some" snow through the evolution. My benchmark is still the 2" thing but nothing wrong with glazing over eye candy as it comes out. 

[Ian]

Like Ji said, the 500mb on these model runs is absolute porn. The best part for you guys is the way it phases warm air would be sent into NE while Philly to DC gets clocked. 

a lot of the 'epic' mid atlantic storms screw ny and new england.

[psuhoffman]

I wonder if Accu realizes Ash Wednesday gave DC 4" of snow. I mean that would be awesome and I know it hammered higher elevation but their press release calls for a potential major blizzard in the cities.

no two storms are exactly alike, 2-3 degrees difference and 50 miles east and that would have been 10" plus in the cities.  Besides Accuhype wants viewers. 

[WxUSAF]

I think the general evolution of the system is understood by the guidance at this point.  The 3 possible "screw jobs" we could get would be

1.  A late phase solution where it all comes together 6 hours too late for us and we watch NJ northeast get nailed (my biggest fear)

2.  The trend of an earlier phase continues and actually ends up cutting this inland (unlikely IMHO right now given the setup)

3.  The whole trough ends up further north then guidance and the storm simply tracks too far north for us (second biggest concern)

I think 1 is a possibility, but I think 2 and 3 are low.  I think a more likely possibility is no phase at all and it just bowling-balls OTS after giving Columbia (South Carolina) some flurries.  

[Inudaw]

NAVGEM since were mentioning all the models today! (I'll save the JMA for Ji!!! )  has slowly shifted south over the passed few runs.   Looks pretty similar to the 12z UKMET..  

[MN Transplant]

NAVGEM is fine.  Doesn't wrap up as much, so the precip is lighter, but we are still in the good quadrant which is all you can hope for.

[Quasievil]

I think the general evolution of the system is understood by the guidance at this point.  The 3 possible "screw jobs" we could get would be

1.  A late phase solution where it all comes together 6 hours too late for us and we watch NJ northeast get nailed (my biggest fear)

2.  The trend of an earlier phase continues and actually ends up cutting this inland (unlikely IMHO right now given the setup)

3.  The whole trough ends up further north then guidance and the storm simply tracks too far north for us (second biggest concern)

I want this storm like everyone else but it's hard to not to be worried by #1 or #3 just like you. That northern stream has not played nice. The seasonal trends last year and this year don't support this solution. Hopefully, we can finally buck them.

[vinylfreak89]

I think 1 is a possibility, but I think 2 and 3 are low.  I think a more likely possibility is no phase at all and it just bowling-balls OTS after giving Columbia (South Carolina) some flurries.  

Are there any models that do this though? Based on the data I've seen, nearly everything has trended toward a partial phase.

[WxUSAF]

Are there any models that do this though? Based on the data I've seen, nearly everything has trended toward a partial phase.

2-3 of the GEFS members are like the Op with a big stalled storm.  Most of the rest do give us some precip.  1 looks like a late phase like Hoffman is worried about, although we still get precip from it.  1-2 are bowling-balls off the SE coast and 1 doesn't have any storm at all.  

[Ian]

late phase should be a concern no matter what around here.. probably until the precip is over us.