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FXUS61 KBTV 161125

Area Forecast Discussion
National Weather Service Burlington VT
625 AM EST Mon Jan 16 2017

Quiet weather is expected today with high pressure over the
region. A warming trend will also take place beginning today and
continuing through midweek with above normal temperatures
expected. However...attention will turn to the late Tuesday into
early Wednesday time period when mixed precipitation makes its
way up into the region. The precipitation will generally begin
as snow before mixing with sleet and freezing rain in northern
New York with colder air holding in longer over Vermont for a
bit more snow and sleet before going to rain on Wednesday.


As of 551 AM EST Monday...Going forecast in good shape. Only 
tweak was to temperatures and sky given the sharp difference 
across the area with clouds and warmer temperatures west and 
relatively clear skies with colder temperatures east. 
Otherwise...with high pressure over the area quiet weather is 
expected today and tonight. A warm trend will also take place 
with highs today in the upper 20s to mid 30s. And it will not be
getting as cold tonight as the past few night with lows in the 
mid teens to lower 20s.


As of 328 AM EST Monday...Active weather is expected during 
this period...especially late in the day Tuesday through the 
morning hours on Wednesday. It will be yet again another mixed 
precipitation event. Highs on Tuesday will actually get into the
30s to around 40 in advance of the precipitation. But with dry 
air in place wet bulbing will take place and the thermal profile
will change significantly with low level cooling and warming 
aloft. At this time its looking like light snow at the onset and
then as warmer air aloft moves into northern New York Tuesday 
night they will have the best chance of seeing sleet and some 
freezing rain that could result in some light ice accumulations.
Secondary low wants to form along the coast Tuesday night and 
this will keep colder air in over the Champlain Valley and 
points east. Thus the thermal profile Tuesday night would 
support the idea of a bit more snow and sleet with some rain 
getting into the Champlain Valley. Freezing rain threat looks 
low in Vermont...but with more snow and sleet...better snow 
accumulations could result. From Tuesday night through Wednesday
areas from the Green Mountains eastward could see snow and 
sleet amounts in the 2 to 5 inch range with around an inch in 
the Champlain Valley before changing to rain. Either way another
messy situation is expected before temperatures warm enough for
rain everywhere on Wednesday. Precipitation should also be 
exiting the region as temperatures warm well into the 30s 
Wednesday afternoon. Only other concern will be strong winds 
moving in late Tuesday...especially in the Champlain Valley that
could cause some shadowing effects and limit precipitation. 

No headlines at this time...but situation for Tuesday night into
Wednesday will be closely monitored given the mixed
precipitation event.


As of 255 AM EST Monday...The middle to later portions of the 
week will generally feature high pressure with very mild 
temperatures, variable clouds and mainly dry weather. This idea 
is broadly supported by a variety of global ensemble guidance so
forecast confidence remains above average. A weak upper trough 
passage Wednesday night/Thursday morning will bring the best 
shot at scattered snow/rain showers during the period, otherwise
minimal pops will be offered through Sunday. Mean 925 mb 
temperatures generally average from -1 to -3C through Saturday, 
then climb slightly by Sunday. Adding a customary +7C to these 
values for January yields max temps from the mid 30s to lower 
40s through the 4 day period with overnight lows in the 20s to 
around 30 in milder valley locales. Of course, any radiative 
effects that do develop during overnight periods of partial 
clearing could yield higher variability in the overnight lows 
than currently shown, but this is not an uncommon occurrence. 
Regardless, daily mean departures should average some +8 to +15 
deg above normal for this time of year continuing the larger 
background trend throughout the winter so far.


.AVIATION /12Z Monday through Friday/... 
Through 12Z Tuesday...Mainly VFR through the period with high
pressure. Brief period of BKN/OVC MVFR cigs in the 018-028 AGL
range expected at KSLK and in the 035-045 AGL range at KMSS
through 15Z. Otherwise mainly SKC/SCT conds. expected. Winds
trending south to southwesterly and occasionally gusty to 20
knots at KBTV/KPBG/KSLK/KMSS this afternoon. After 00Z winds
abate to light with VFR continuing.

12Z Tuesday - 18Z Tuesday...VFR with surface high pressure
18Z Tuesday - 00Z Thursday...MVFR/IFR in periods of light snow,
mixed pcpn and/or light rain depending on location.

00Z Thursday through 00Z Friday...VFR with brief MVFR/IFR
rain/snow shower activity.

00Z Friday onward...VFR.





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