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fxus61 kbtv 030859 
afdbtv 


Area forecast discussion 
National Weather Service Burlington Vermont 
359 am EST Wednesday Dec 3 2008 


Synopsis... 
high pressure will exist over the north country today bringing dry 
weather and temperatures slightly above seasonal normals. The dry 
weather will be short lived as a cold front moves in on Thursday 
and brings rain and snow to the area. Once the cold front moves 
through Thursday night...colder air will be ushered in and below 
normal temperatures are expected right through the weekend. 


&& 


Near term /through tonight/... 
as of 358 am EST Wednesday...clouds will continue to lift north 
out of the region this morning and skies should become partly or 
mostly sunny as high pressure builds into the region. High 
temperatures today will once again be above seasonal normals. A 
strong cold front will move toward the region later tonight with 
the possibility for some light rain or snow after midnight across 
northern New York. 


&& 


Short term /Thursday through Friday/... 
as of 358 am EST Wednesday...strong cold front to move across the 
area on Thursday. Well defined signatures at the 850 and 700 mb 
levels with respect to frontogenesis indicate sufficient forcing 
for precipitation to develop. Strong pressure gradient will also 
lead to gusty south to southwest winds...which will help to limit 
the amount of precipitation across the Champlain Valley. 
Temperatures will be in the middle 30s to around 40 which suggests 
the larger valleys will see a mix of rain or snow while the 
mountains remain cold enough for snow. However...any snow 
accumulations should generally be 2 inches or less. Gusty west to 
northwest winds will develop Thursday night as the cold front 
passes and northwest flow aloft develops. Lake effect snows should 
kick in across Lake Ontario...but the northwest flow aloft should 
keep the bulk of this precipitation south of the area. 
However...the flow aloft backs on Friday and this should allow for 
some of the lake effect to move into the area. Temperatures on 
Friday will be below normal due to cold air advection. 


&& 


Long term /Friday night through Tuesday/... 
as of 358 am EST Wednesday...southwest flow aloft develops over 
the area Friday night and Saturday and this will allow any lake 
effect snow band off Lake Ontario to lift northward into northern 
New York and have maintained a chance of snow over this area as a 
result. The remainder of the area should continue to be dry. It 
now appears that digging shortwave trough to our west wants to go 
more into the Ohio Valley and middle Atlantic region...which would 
keep best dynamic support further to the south. Nevertheless... 
upper trough axis moves across the area Sunday and Sunday night 
and this will bring some light snow to the north country. Cold air 
is reinforced over the area on Monday as northwest flow aloft 
redevelops over the region...but this will be short lived as 
another shortwave trough moves toward the area. Warm air advection 
precipitation should impact the area on Tuesday with another 
chance of snow expected. 


&& 


Aviation /09z Wednesday through Sunday/... 
through 06z Thursday...generally broken/overcast VFR conds will be offered 
for much of the period as broad-scale south to southwesterly surface 
flow increases today ahead of advancing clipper system. Best conds 
likely at the Vermont terminals where some breaks in the overcast likely 
today. Most pessimistic conds will be offered at northern New York sites...especially 
kslk where lingering -shsn and pesky MVFR stratus will likely hold 
tough through sunrise. Some gusts to 20-25kt possible later this 
morning into this afternoon at kbtv/kslk/kmss as boundary layer mixes to 
near 2 kft. 


From 06z Thursday through Sunday...MVFR to occasional IFR late Wednesday 
night into Thursday in rain/snow showers as cold front moves across the 
region. VFR to occasional MVFR Friday and Saturday...except possible IFR at 
kslk in lake effect snow/weak clipper system. MVFR to occasional IFR in 
snow on Sunday. 


&& 


Equipment... 
the AWOS (automated weather observing system) at krut (rutland- 
southern Vermont regional airport) continues to report erroneous 
dew point data...and thus the relative humidity data for this 
site is also erroneous. The FAA has maintenance responsibility 
for the AWOS at krut. It will likely be sometime this week at the 
earliest before the dew point sensor at krut can be repaired. 


In addition...the temperature sensor at kmvl ASOS (morrisville- 
Stowe airport) is reporting erroneous temperatures due to an 
inoperative fan. Ets have been notified and a part is on order. 
The problem will be fixed within the next couple of days. 


&& 


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


&& 


$$ 
Synopsis...evenson 
near term...evenson 
short term...evenson 
long term...evenson 
aviation...rjs/jmg 
equipment...weather forecast office btv