Jump to content
  • Member Statistics

    17,508
    Total Members
    7,904
    Most Online
    joxey
    Newest Member
    joxey
    Joined

December 16/17 Winter Event


MN Transplant
 Share

Recommended Posts

3 minutes ago, psuhoffman said:

I am mostly happy with this run.  It was a much colder run, especially at the surface.  Never gets places from 95 NW above freezing.  Probably means more sleet then rain during the "mixy" period.  Unfortunately a slightly more tucked in track mean't it did blast a warm layer pretty far west at 850...it gets right to my doorstep at its furthest NW.  For big totalys into 95 we would want to see that surface track judge just a bit southeast...but the good news is if the euro and ggem are correct on the colder thermal structure of the storm we wouldn't need the track to adjust all the way to the GFS.  That's good because in the end I expect a 60/40 compromise track between the usually progressive GFS and the usually amped euro, biased toward the euro, to be reality.  That is going to cut it really close for getting big totals into 95.  But if we adjust the euro just a slight bit southeast on the surface track it gets it done.  

850 looks to be the warm layer.  925 and surface stay below freezing for the duration IMBY.  So snow-sleet-snow, which is what I always expected. Definite banding signature on the back end around 6z that moves through to the east after that.  But still a pretty nice front end before mixing for many...3-6"?  

  • Like 1
Link to comment
Share on other sites

6 minutes ago, psuhoffman said:

I am mostly happy with this run.  It was a much colder run, especially at the surface.  Never gets places from 95 NW above freezing.  Probably means more sleet then rain during the "mixy" period.  Unfortunately a slightly more tucked in track mean't it did blast a warm layer pretty far west at 850...it gets right to my doorstep at its furthest NW.  For big totalys into 95 we would want to see that surface track judge just a bit southeast...but the good news is if the euro and ggem are correct on the colder thermal structure of the storm we wouldn't need the track to adjust all the way to the GFS.  That's good because in the end I expect a 60/40 compromise track between the usually progressive GFS and the usually amped euro, biased toward the euro, to be reality.  That is going to cut it really close for getting big totals into 95.  But if we adjust the euro just a slight bit southeast on the surface track it gets it done.  

Ha, mostly happy. It crushes you and given the fact it's probably too amped and a blend of the Euro/GFS is best, you are probably getting somewhere close to two feet, maybe more.

Link to comment
Share on other sites

2 minutes ago, WxUSAF said:

850 looks to be the warm layer.  925 and surface stay below freezing for the duration IMBY.  So snow-sleet-snow, which is what I always expected. Definite banding signature on the back end around 6z that moves through to the east after that.  But still a pretty nice front end before mixing for many...3-6"?  

So...what we gotta get to turn that 3-6" to 6-8" for us 95 folks? :D (may sound a bit greedy, but as I said, my bar for this was 5" or more to get a verified WSW...and I'm afraid 3-6" may fall short, lol)

Link to comment
Share on other sites

7 minutes ago, BTRWx's Thanks Giving said:

Has there ever been a winter where D.C. gets a big hit in December then nothing the rest of the season? That's what many winter outlooks would show considering this storm.

Nov-Dec 1989 had a few decent storms for DC, along with one of the greatest cold periods of all time. But then once the clock hit 1990, the rest of the winter torched.

  • Like 2
Link to comment
Share on other sites

Just now, Maestrobjwa said:

So...what we gotta get to turn that 3-6" to 6-8" for us 95 folks? :D (may sound a bit greedy, but as I said, my bar for this was 5" or more to get a verified WSW...and I'm afraid 3-6" may fall short, lol)

Need the GGEM's thermal profiles and a slower forward speed?  For DC to verify WSW, there's going to have to be some CCB snow almost certainly.  GGEM would nearly get it done with the WAA snow before mixing.  

Link to comment
Share on other sites

6 minutes ago, WxMan1 said:

Yeah, you want to talk gradients, PG and AA Counties here in MD are like, hold my beer..

Very..  I'm in northern AACo and feel like I'll be able to drive 30 mins to either a slushy inch or a foot. If that means I get 3-6 I'm perfectly fine with that but the bleeding must stop. Euro walked me off the ledge a little which is kind of rare.

  • Like 1
Link to comment
Share on other sites

3 minutes ago, WxUSAF said:

850 looks to be the warm layer.  925 and surface stay below freezing for the duration IMBY.  So snow-sleet-snow, which is what I always expected. Definite banding signature on the back end around 6z that moves through to the east after that.  But still a pretty nice front end before mixing for many...3-6"?  

If we were to assume this run verbatim looking at the 1 hour temps at all levels and the precip I would say about 3-6 before a change to sleet for people from 95 NW.  Then it gets tricky...there is about 6 hours of crazy banding with pockets cold enough to support snow and pockets in the subsidence in between that are sleety.  The odd thing is some of the warm pockets don't line up with the banding.  Has a warm pocket over the NW burbs around 3z while they are getting smoked by the deform.  But I am NOT sweating that kind of thing at this range.  I actually think temps crash a little faster once the storm reaches our latitude and we probably mix out that warm layer better for the back end.  But as is...it only flips back to pure snow for a couple hours at the end..but its puking snow so maybe another 2-3" on the back side after a crap ton of sleet.  But again...that is not my forecast...I would adjust this slightly to the southeast and mix out some of those warm pockets a little better during the deform.  Not a lot...but the euro is often SLIGHTLY overdone.  Slightly makes a huge difference on the edges like we are.  

  • Like 1
Link to comment
Share on other sites

18 minutes ago, Wentzadelphia said:

This is on a lot of guidance. Think it has to do with how the ULLs are being stacked. Looking like a less beefy 2016 here in Philly where we get some snow and then the deformation zone heads NW 

Its just an indication of sinking air adjacent to the strong lift in the fronto banding. The exact location of these features will be fun to track and pin down on the mesos pretty soon. Ofc we all pretty much know where the best banding will set up.

Link to comment
Share on other sites

43 minutes ago, Maestrobjwa said:

So...what we gotta get to turn that 3-6" to 6-8" for us 95 folks? :D (may sound a bit greedy, but as I said, my bar for this was 5" or more to get a verified WSW...and I'm afraid 3-6" may fall short, lol)

You've gotta hope the storm isn't so amped, and that the 50/50 low and/or the Canadian high is strong enough to shunt the storm east. A big disadvantage of December storms is the very warm ocean, so the track matters a great deal especially for the coastal plain.

  • Like 1
Link to comment
Share on other sites

8 minutes ago, HighStakes said:

One thing that has me a little confused is why the 850's arent crashing more during the deform band. Usually we kill it up here with ratios in a deform band so I would think we be more like 12-1 instead of 15/20-1.

I saw that...that warm pocket gets right to our door then stalls and sits there for 6 hours...I don't buy that.  Some of that period we are getting .2 QPF per hour.  I would adjust that.  Even with that there we would likely be puking snow/sleet mix during that 6 hour period...low ratio but we would likely still go way over a foot...just not those stupid totals on the clown maps.  But again, worrying about a little warm layer pocket like that and banding at this range is useless.  

6 minutes ago, osfan24 said:

Ha, mostly happy. It crushes you and given the fact it's probably too amped and a blend of the Euro/GFS is best, you are probably getting somewhere close to two feet, maybe more.

I am analyzing for the DC/Baltimore area where most people in here are.  Not only talking to the 3 people that live near me.  But sorry.  I will try to focus on my yard more.  

  • Like 2
  • Haha 2
Link to comment
Share on other sites

3 minutes ago, psuhoffman said:

If we were to assume this run verbatim looking at the 1 hour temps at all levels and the precip I would say about 3-6 before a change to sleet for people from 95 NW.  Then it gets tricky...there is about 6 hours of crazy banding with pockets cold enough to support snow and pockets in the subsidence in between that are sleety.  The odd thing is some of the warm pockets don't line up with the banding.  Has a warm pocket over the NW burbs around 3z while they are getting smoked by the deform.  But I am NOT sweating that kind of thing at this range.  I actually think temps crash a little faster once the storm reaches our latitude and we probably mix out that warm layer better for the back end.  But as is...it only flips back to pure snow for a couple hours at the end..but its puking snow so maybe another 2-3" on the back side after a crap ton of sleet.  But again...that is not my forecast...I would adjust this slightly to the southeast and mix out some of those warm pockets a little better during the deform.  Not a lot...but the euro is often SLIGHTLY overdone.  Slightly makes a huge difference on the edges like we are.  

So when can we expect to see your forecast? Tomorrow?

Link to comment
Share on other sites

Just now, psuhoffman said:

If we were to assume this run verbatim looking at the 1 hour temps at all levels and the precip I would say about 3-6 before a change to sleet for people from 95 NW.  Then it gets tricky...there is about 6 hours of crazy banding with pockets cold enough to support snow and pockets in the subsidence in between that are sleety.  The odd thing is some of the warm pockets don't line up with the banding.  Has a warm pocket over the NW burbs around 3z while they are getting smoked by the deform.  But I am NOT sweating that kind of thing at this range.  I actually think temps crash a little faster once the storm reaches our latitude and we probably mix out that warm layer better for the back end.  But as is...it only flips back to pure snow for a couple hours at the end..but its puking snow so maybe another 2-3" on the back side after a crap ton of sleet.  But again...that is not my forecast...I would adjust this slightly to the southeast and mix out some of those warm pockets a little better during the deform.  Not a lot...but the euro is often SLIGHTLY overdone.  Slightly makes a huge difference on the edges like we are.  

Yeah, not time to diagnose mesoscale features yet and it's hard with the Euro since we don't have skew-t's.  Those seemingly inconsistent things usually resolve themselves.  Either way, seems like we're generally in a pretty good spot for the CCB to rip.  Locations farther N/E most favored.  You and @mappy probably get smoked.  @showmethesnow and @mitchnick's new house are in absolute prime position.  

Link to comment
Share on other sites

6 minutes ago, psuhoffman said:

I saw that...that warm pocket gets right to our door then stalls and sits there for 6 hours...I don't buy that.  Some of that period we are getting .2 QPF per hour.  I would adjust that.  Even with that there we would likely be puking snow/sleet mix during that 6 hour period...low ratio but we would likely still go way over a foot...just not those stupid totals on the clown maps.  But again, worrying about a little warm layer pocket like that and banding at this range is useless.  

I am analyzing for the DC/Baltimore area where most people in here are.  Not only talking to the 3 people that live near me.  But sorry.  I will try to focus on my yard more.  

No, please keep analyzing the DC metro area.  Thanks.  

  • Like 1
Link to comment
Share on other sites

  • WxUSAF unpinned and locked this topic
Guest
This topic is now closed to further replies.
 Share

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...