FXUS61 KBTV 110830
Area Forecast Discussion
National Weather Service Burlington VT
330 AM EST Tue Dec 11 2018
Relatively quiet mid December weather conditions will persist
through the end of the work week. Increasing cloudiness is
expected today as a weak upper level disturbance over the
northern Great Lakes shifts eastward. This system will bring
periods of light snow tonight into Wednesday morning, with just
a dusting to an inch expected in most areas. A cold front in the
wake of this disturbance will result in high temperatures on
Wednesday 10 to 15 degrees below normal. Temperatures will
gradually moderate on Thursday and Friday, with highs likely
reaching 35 to 40 degrees for Friday.
.NEAR TERM /THROUGH WEDNESDAY/...
As of 316 AM EST Tuesday...Another chilly start this morning
with 08Z readings generally in the single digits above zero,
except locally zero to -10F in the nrn Adirondacks and across
far nern VT. Bands of mid and upper level clouds streaming ewd
ahead of shortwave trough across the nrn Great Lakes acting as a
bit of a brake on longwave cooling, so we should be near the
pre-dawn lows at this point. Relatively quiet day ahead with
weak south to SW winds (5-10 mph) in advance of sfc low across
the nrn Great Lakes. Will see a gradual increase in cloud cover
through the daylight period from west to east, resulting in lows
a few degrees cooler than yesterday. Generally looking for highs
in the mid-upr 20s.
Shortwave trough traverses the region this evening and
overnight from west to east, with increasing chances for light
snow showers, especially across nrn NY. Have indicated PoPs of
30-40% before diminishing during the morning hours on Wednesday
as sfc reflection dissipates across VT. Limited moisture
availability with this system, and should limit snowfall amts to
a dusting to 0.5" in most sections. Some modest moisture
advection from Lake Ontario and orographic ascent into the
Adirondacks may yield around 1" or so of light fluffy (20:1 SLR)
snow accumulation across nrn NY. Will see lows tonight mainly
in the mid-upr teens under overcast skies. A shallow surge of
low-level CAA and northerly winds around 10 mph behind the
trough will bring colder temps on Wednesday, with daytime
temperatures generally in the upr teens to lower 20s. Should see
a gradual clearing of low stratus...especially during the
afternoon and evening hours on Wednesday.
.SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY NIGHT/...
As of 316 AM EST Tuesday...Very quiet conditions are expected mid-
week as surface high pressure and a building ridge aloft dominate
over the Northeast. As such, PoPs are nil with the main forecast
challenge being clouds and temps. As the high centers over the
region Wednesday night we should see ideal conditions for
radiational cooling develop with temps area- wide in the single
digits above to teens below zero. For Thursday the high begins to
ever so slowly shift east allowing for a good rebound in temps into
the mid/upper 20s by the afternoon. Increasing south/southwesterly
return flow will also allow for some increasing mid/high clouds
which will make for a cloudy sunset and overnight, moderating lows
in the teens to low 20s.
.LONG TERM /FRIDAY THROUGH MONDAY/...
As of 316 AM EST Tuesday...Still a bunch of uncertainty going into
the weekend in regards to precip chances, but the trend appears to
be towards drier conditions. Latest FV3 and ECMWF are in rather good
agreement showing surface high pressure holding strong over the
Atlantic coast for Friday and into Friday night while cutoff low
pressure over the Ark-La-Tex region slowly trudges east. Meanwhile
to the north, an upper trough begins to take shape over the Canadian
Prairies and drops through the forecast area on Saturday with no
phasing with the southern stream system. This is in stark contrast
to the operational GFS which shows the northern and southern streams
phasing and significant chances for precipitation come Sunday, but
it appears to be the outlier even amongst the GEFS. With that in
mind, the forecast highlights the best chance for precipitation
being late Friday night through Saturday being mainly rain early
with a chance for snow showers late as a cold front drops into the
region Saturday night. Drier and cooler conditions would return for
Sunday under a weakening upper ridge with additional chances for
snow showers Monday associated with another upper trough passage.
.AVIATION /08Z TUESDAY THROUGH SATURDAY/...
Through 12Z Wednesday...Seeing some localized MVFR stratus in
vcnty of Lake Champlain with light winds and cold air in place.
This may occasionally result in BKN-OVC020 at PBG/BTV thru
11-12Z before these localized stratus dissipate. Otherwise,
increasing VFR cloudiness is expected from west to east as a
mid-level wave approaches from the northern Great Lakes. Will
see developing MVFR ceilings tonight and HIR TRRN OBSCD along
with periods of 3-5SM in light snow. Isold IFR conditions are
possible at SLK tonight. Winds will be relatively light, mainly
south 5-8kts during the daylight hours today, and returning
light and variable after sunset.
Wednesday: Mainly VFR, with local MVFR possible. NO SIG WX.
Wednesday Night: VFR. NO SIG WX.
Thursday: VFR. NO SIG WX.
Thursday Night: VFR. NO SIG WX.
Friday: VFR. Slight chance SHRA, Slight chance SHSN.
Friday Night: Mainly MVFR, with areas VFR possible. Chance SHRA,
Saturday: Mainly VFR, with areas MVFR possible. Chance SHRA,