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Hey Scott, your forecast is an interesting read regarding the Great Lakes 
Low being less warm and rainy than expected.  If you don't mind, let me give 
this hands-on report  about  what *appears* to be moving east. (disclaimer: 
no science involved):

Yesterday:  Drove to Toronto to visit Dad in hospital, recovering from new 
valve sewn in his heart.  Brilliant sunshine, windows partly down. 
Fifty-plus degrees.  Arrived and visited.  Painful, as such visits usually 
are. Hospital needs air conditioning on, badly. Dying of stuffiness inside. 
Went out for a walk. Wandered around downtown core.  Noticed many young 
ladies wandering around in crop-tops and tattoos.  Reminisced, sadly, when 
ladies with tattoos were seen only in circuses and had beards. Street 
performers out fooling around, strumming guitars and looking generally 
seedy, but otherwise employable.  Forced to slough off panhandlers emerging 
from every edifice with Tim Horton's collection cups.  Fifty percent not 
appearing employable.
Synopsis: A typical late April day in Toronto.

Today:  Woke up.  Going skiing for first day this season.  Last night, 
website reported Holiday Valley 100% open due to 16 inches of new snow/snair 
this week.  Psyched by report from Jonny who attended on Friday night.. 
"Good, icy in spots" ringing in my ears.  Very psyched.  Then, looked 
outside.  Rain, becoming buckets of rain.  Mud in fields somewhat muddier 
than the last thirty-five straight days of mud.  Looked at Ellicottville 
hourly forecast on web.  Forty degrees expected.  Rain expected to contiue 
all day, heavier later and overnight.  Looked at WNY ten-day forecast.  No 
snow expected through February 6th.
Synopsis: Shrugged.  Went to church instead.


No, I didn't pray for snow, but I should have.

YMMV
Leigh


----- Original Message ----- 
From: "Scott Braaten" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Sunday, January 29, 2006 12:20 PM
Subject: [SKIVT-L] Forecast For the Next 48 hours...Snow and Ice (Complex)


> Models used: 12z GFS, 12z NAM, 12z Suny MM5, 15z RUC out to 12hrs, and 9z
> SREF (NAM ensembles).  No global models were used as I find their graphics
> and resolution leaving something to be desired inside of 48hrs.
>
> This forecast will be divided up into two seperate systems.  First one is
> in the Great Lakes, second will be developing off the east coast.
>
> Most interesting note in the latest 12z models is that they are trending
> back to a slightly colder solution with the first system.  I doubt many
> areas save the Champlain Valley go over to rain and if it ever warms up
> enough for plain rain it'll be once best moisture and dynamics lift north
> of the region...I usually envision how a weather system will evolve in my
> head right down to how the radar will look and precipitation types.  This
> will be a warm front precipitation event on the front side as the low in
> the Great Lakes rotates its warm front northward through the area.  Weak
> secondary development in the Gulf of Maine will keep the cold air in place
> from the Green Mountain Spine eastward.  12z MM5's higher resolution shows
> this quite well as 925mb temps (1,000-1,500ft) never go above freezing
> from the Green Mountain spine eastward during the entire event while
> spitting out 1/2" of QPF...and the MM5 actually strengthens the cold air
> east of the Green Mtn spine once the secondary development occurs dropping
> the freezing line back down through Concord, NH/Bennington County,
> VT/Burlington, VT line...the only places to truely hit the warm sector are
> the Adirondacks and Champlain Valley SWward.
>
> http://www.atmo.arizona.edu/gifs/USRADCOMP.GIF
>
> Here you can see the Great Lakes low...but what I've noticed this morning
> is that the precipitation shield is either weakening and/or precipitation
> is considerably less than what models were pumping out last night.  Thus,
> some changes have occurred with the 12z model runs as the second low is
> brought closer to the coast.  On the above loop, you can see a lot of
> energy diving into the base of the trough out of Central Rockies region.
>
> So first system forecast...quick 3-5hr burst of snow and it could be
> moderate to heavy for a brief hour or so this evening.  QPF rates would
> suggest the potential for a band (warm front) of 1"/hr snowfall to move
> through the region this evening especially as this band interacts with the
> Green Mountains.  Then precipitation will quickly shut off or turn to
> drizzle as a warm pocket moves through the 2K-5K feet region with freezing
> drizzle below that or snow/sleet above that.  For those of you who are
> wondering what a temperature profile that I look at is...
>
> http://www.uvm.edu/~sbraaten/tempa.png
>
> That is the 12z NAM/ETA for the South Burlington airport (KBTV).  850mb is
> roughly 5,000ft, 925mb is roughly 1,500ft. Its not an exact scale but this
> model isn't exactly right either.
>
> Interesting to note, as I've been writing this, the temp at the house in
> downtown Burlington has dropped from 34.2 to 33.0F...so a falling
> temperature has been noted during the daylight hours.
>
> Total Snow/Ice Accums through tomorrow morning:
>
> 2-5" northern Adirondacks, Green Mountains north of RT4/Killington region,
> and all White Mountain resorts...with possibly a 1/10" of ice on top from
> freezing drizzle but that shouldn't be a big deal.  I do not expect more
> than 30% of this area will rise above freezing and it'll likely be at some
> layer slightly above the valleys (2-5K feet) stripe could punch into the
> mid 30's overnight.
>
> 1-3" southern Adirondacks, Champlain Valley, southern Green Mountains and
> possibly extreme northern Berkshires.  1/10" of ice on top...only
> sheltered valleys will stay below freezing but 75% of this area should
> rise to 33-35F tonight.
>
>
> Storm #2.  This was going to be the biggie for Tuesday.  Still up in the
> air as to what happens.  The weaker the low in the Great Lakes is, the
> stronger and closer to the coast the second system will be.  They both
> can't be strong as one will take energy from the other.  Yesterday, since
> this second system could have a large impact on parts of the northeastern
> major metro regions, NOAA aircraft did a special airdrop of 13 balloons
> into the atmosphere out in the Pacific to get a handle on the energy
> entering North America.  I remember them doing that with a nor'easter last
> Feb/March.  Needless to say, last nights model runs started bring the
> second system back to the west and the ensemble mean of the operational
> NAM and GFS are very, very interesting.
>
> Both major american models have 16 step-sisters and they make up the
> ensembles.  Each one is slightly skewed in its algorithm from the
> operational.  The average of these 16 members is compiled by NCEP and put
> out as an ensemble mean.  09z SREF (00z ensemble mean of the NAM/ETA) and
> 00z GFS ensembles are further west than the operational solutions.  Thus,
> both bring in more precipitation (all snow everywhere from I-90 northward
> now) than the operational models...with a surface low pressure track over
> the benchmark.  This spells significant snowfall for southern to central
> New England with lighter snows the further northwest one goes.  This
> forecast will need to be refined once the first system moves through.  My
> gut feeling is that a 5-10" snowfall will occur in southern to central New
> England with the axis of heaviest snowfall accumulations running from the
> southern Berkshires through Worcester through Concord and then up into the
> Augusta area of Maine.  However, a deformation band looks to develop with
> strong frontogenic forcing well to the NW of the coastal low.  This could
> be another axis of heavier snowfall that affects regions from northern VT
> through the southern Adirondacks.  It might not be on the operational
> models but a strong signal for banded snowfall away from the main shield
> is noted on the ensembles.  Tuesday and Wednesday should be at least
> decent, if not good, ski days across Vermont-New Hampshire-Maine-N. Mass.
>
> More work on the second system later.
>
> -Scott
>
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