Weather

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Area forecast discussion 
National Weather Service Burlington Vermont 
327 PM EDT Thursday Aug 28 2008 


Synopsis... 
surface high pressure will retreat to the northeast as a weak cold 
front approaches from the Great Lakes region. The front will bring 
a chance of rain showers on Friday night into Saturday then 
clearing...with beautiful dry weather returning for Sunday and 
Labor Day. A significant warm up appears likely next week with 
high temperatures well into the 80s by the middle of next week. 


&& 


Near term /until 6 am Friday morning/... 
as of 308 PM EDT Thursday...tonight...500mb ridge will weaken and move off to the 
east...as high clouds from a weakening cutoff trough continue to 
stream across the area. Currently looks like 850-600mb level will 
be dry to support any chance for precipitation over Saint Lawrence County 
this evening...so once again going with a dry forecast tonight. The 
nighttime warming trend continues with most areas in the middle to upper 
50s tonight. Surface dewpoint temperatures have increased to the middle-upper 
50s today...so valley fog looks like a good bet after 06z this evening 
across climatology favored Vermont locals. Fog will not be as likely over New York due to 
increased cloud cover this evening...which will hinder radiational 
cooling. 


&& 


Short term /6 am Friday morning through Saturday night/... 
as of 308 PM EDT Thursday...weak surface cold front will approach Saint Lawrence 
County by Friday evening and progress across the County Warning Area through 
Saturday. Middle-level lapse rates look unimpressive and overall lift 
looks weak with primary upper level forcing lifting north of the 
area...so just going with a chance for rain showers during frontal passage 
across the area. The front should be through New York by 12z Sat and 
through Vermont by 18z. Skies should become mostly sunny behind the 
front for most the County Warning Area...with the exception of NE kingdom as a 
second upper level vorticity maximum and cold pool aloft will advect over 
the area late Saturday evening...into Sunday morning. This will 
allow clouds to hang on over this region a little longer...but New York 
and eastern Vermont should be mostly clear by Sunday morning. Overall temperatures 
will be slightly above normal with highs in the middle-to upper 70s and 
lows in the upper 50s to lower 60s. Winds will be light out of the 
south...then switch to the west/northwest behind the front. 


&& 


Long term /Sunday through Thursday/... 
as of 308 PM EDT Thursday...the extended portion of the forecast 
still looks unseasonably warm and dry. Upper level trough will push 
east of the forecast area on Sunday...leaving behind a slight chance 
of showers in the Northeast Kingdom through the morning hours and 
some clouds across the County Warning Area. Then surface high pressure and large 
upper level deep ridge build into the area Sunday night through 
Wednesday. Models have come into very good agreement...forecaster 
confidence is higher than average. Tuesday continues to look like 
it will be the warmest day...probably middle 80s in the valleys. Lots 
of subsidence across the area will provide US with mostly clear 
skies. 


&& 


Aviation /19z Thursday through Tuesday/... 
through 18z Friday...satellite imagery currently showing leftover 
middle/upper level moisture from Tropical Storm Fay is slowly moving 
across and past our taf sites...while strong ridge remains across 
our County Warning Area. Clouds have started to dissipate and will continue to 
this afternoon...with some more valley fog possible after 06z 
Friday at mpv/slk. Have mentioned 1/4 to 1/2 sm in fog with 
ceilings ovc001 by 07z tonight...all taf sites will be back to 
VFR by 13z. 


18z Friday through Monday...VFR conditions will prevail across our 
taf sites Friday...before a surface cold front associated with a 
developing middle/upper level trough across the Great Lakes interacts with 
leftover moisture from Fay. This moisture and some ulvl support 
will produce showers with an embedded rumble of thunder Friday into 
Saturday. A brief period of MVFR conditions will be 
possible...along with some morning fog at mpv/slk...which will 
produce vlifr conditions between 08-12z each morning. Surface high pressure 
redevelops behind trough with VFR conditions expected through Monday 
across our taf sties. 


&& 


Btv watches/warnings/advisories... 
Vermont...none. 
New York...none. 


&& 


$$ 
Synopsis...Dumont 
near term...Dumont 
short term...Dumont 
long term...Jan 
aviation...Jan