Print

Print


On Wed, 14 Dec 2005 08:18:24 -0500, Jim 'Rusty' Clapp <[log in to unmask]> 
wrote:

>Hey Scott- will the backside of this system be warm or cold? i.e., will we
>have wrap-around cold air with ending cold snow, (good) or a warm ending 
to
>the event (bad) I am thinking Northern Greens, that is.
>thanks, Jijm
>

Backside of the storm will be cool, but not cold by post-storm standards.  
This storm does not bomb out and will not result in the usual post storm 
40mph north winds with very cold temps.  The backside looks to be cool but 
the wind flow will be more out of the west...bringing in an airmass that 
has modified over the Great Lakes.  Still, some back lash upslope snow 
showers are possible as well but this one won't have one of thost nice 
post-storm mountain upslope events.  That's usually one of the best part 
of any coastal storm...sure it snows on the front side, but then it pounds 
the mountains on the backside.  Think March 3rd last year, I think?

Anyway, this morning I'm still having a hard time with BTV's call for all 
snow.  They say they are going with the GFS but even it has a warm layer 
punch in around 6,000ft for a time.  There's a distinct 3-4hr period at 
Burlington, Rutland, Springfield and Montpelier that all have a sleet  
profile...with Rutland and Springfield going over to freezing rain as the 
depth of the warm air layer increases to several thousand feet thick.  
Actually, the GFS warms up Sringfield enough to go over to plain rain 
briefly as the low pressure tracks right nearby....while keeping areas 
west of the Green Mtn spine colder both at the surface and aloft.  
However, I have a hard time believing the cold air that we've got in place 
right now is going to go anywhere fast so I still think a change to plain 
rain will not happen anywhere in the state of Vermont.  I just find it 
interesting that BTV is going with all snow for its forecast area...even 
when both the NAM and GFS punch in a warm layer for a time.  

I actually think it would be interesting if this all pans out, to go 
skiing on Friday and carry a thermometer.  I bet you could see 1,200ft at 
the base of Mansfield be 24F and then hike to the summit at 4,300ft and 
watch it punch to the low 30's.  You'd have to time it right as the window 
for the warm air aloft looks to be only a couple hours before the entire 
column goes cold again.  

Another thing to note is the max snowgrowth does not appear to be lined up 
very well with the best omega lift...its hard to tell exactly on the 
graphics I'm looking at (I really need to download and get familiar with 
BUFKIT as that would make this much easier...something to do over the 
holiday break).  All in all, this looks fairly complicated and much more 
so than BTV makes it seem.

Then looking past modelology and going to meteorology...the GFS looks 
suspect in how low its forecasted precipitation amounts are.  With a low 
pressure system tracking in from the south, and a large area of uniform 
lift moving across the region before trying to develop into a mature storm 
with a deformation on the backside, I think the GFS and European models 
are underplaying the amount of precipitation that falls across VT.

Of course, we still have 48hrs to go before anything happens, full 
forecast tomorrow, but I'm still leaning with 6-12" in most of upstate NY 
with 4-8" across VT with a period of sleet in the middle possible.  This 
might not sound like much, but the woods could use some compaction and 
dense stuff.  I traversed into a steeper slot yesterday which held a 
decent 20-24" of snow but it was all fluff...first turn and the entire 
thing sluffed off to moss and ended up in a big pile 20 yards below me.  
We need something to hold this snow in place and pack it down.

-Scott  

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
SkiVt-L is brought to you by the University of Vermont.

To unsubscribe, visit http://list.uvm.edu/archives/skivt-l.html