Area Forecast Discussion
Issued by NWS Burlington, VT-- Highlight Changed Discussion --
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FXUS61 KBTV 010755
Area Forecast Discussion
National Weather Service Burlington VT
255 AM EST Thu Dec 1 2016
Rain will continue to spread across the North Country tonight
with strong gusty winds possible through early Thursday morning.
On Thursday, the rain will become focused around the higher
terrain, changing to snow Thursday night. Terrain focused
precipitation will continue Friday into Saturday, followed by a
brief period of drier weather on Sunday.
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
As of 937 PM EST Wednesday...Have updated to reflect current
observations and radar trends. Steadier rain will move across
the forecast area between 6z and 12z. Have increased overnight
minimum temperatures. Clouds and precipitation will prevent
temperatures from falling very much, especially with small
dewpoint depressions. Previous discussion follows.
Strong wind gusts expected tonight. Have issued SPS for
subadvisory criteria. But cannot rule out isolated areas
reaching advisory criteria, mainly near the summits.
Large low pressure system will continue to push rain into the
North Country, along with strong low level jet moving into the
region. GFS and NAM indicate 50 kt jet at 850mb around 06Z,
exiting NEwd around 12Z. Local BTV2km model shows SE jet
resulting in strong downsloping wind gusts on western slopes
peaking in strength at 06Z. As rain spreads across the area,
question is how long will mixing last before stabilizing effects
of the rain. BUFKIT models show mixing limited to about 950mb
with winds decreasing starting 08z.
Cooling 925mb temperatures early in the night, trending warmer
after 06Z Thursday. The aforementioned strong gusty winds are
expected to diminish around 09Z as BL shrinks. With rain and
clouds, expect Min temperatures in the mid 30s to mid 40s.
Come Thursday morning, main precip shield will lift to the
north and east, with rain showers expected to concentrate around
the higher terrain as we remain under cyclonic flow. Max
temperatures will be in the 40s.
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
As of 255 AM EST Thursday...By Friday into Saturday the large-
scale upper low/cyclonic gyre will slowly translate east across
southern Quebec and into the maritimes by late in the period.
Background synoptic flow will transition from west/southwesterly
to northwesterly over time and with ample low to mid level
moisture scattered to numerous orographically-enhanced rain and
snow shower activity looks likely. Highest coverage should occur
on Friday with passage of the primary thermal trough with
coverage slowly waning on Saturday. With abundant cloud cover
narrower than normal diurnal temperature swings are expected
with highs in the 40s on Friday cooling to the 30s on Saturday.
Lows Friday night ranging from the upper 20s to mid 30s.
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
As of 255 AM EST Thursday...Any lingering scattered rain/snow
shower activity then comes to an end Saturday evening as surface
high pressure builds into the region. This will set the stage
for fair and dry conditions on Sunday with seasonably cool highs
in the 30s.
By Monday into Tuesday of next week sensible conditions shouldn`t be
all that bad. A dampening mid-level trough will pass through the
region on Monday with just an outside chance of a few rain or snow
showers and some clouds, otherwise dry weather should prevail with
at least some partial sunshine expected. Temperatures again within a
few degrees of seasonal early December norms.
Looking further out into later next week medium range solutions
continue to show a general re-amplification of the flow across the
lower 48 as a pronounced early-season arctic surge pushes southward
into the Rockies and northern high plains. This will eventually set
the stage for cyclogenesis across the central plains which will
track northeastward over time. Rather significant differences remain
however on where this will occur with the operational GFS remaining
on the more progressive side of the guidance. For now have generally
offered a gradual increase in pops/clouds from Wednesday onward as
threat of rain/snow shower activity returns with initial warm
.AVIATION /08Z Thursday THROUGH Monday/...
Through 06Z Friday...Active aviation weather conditions over
the next 24 hours. Frontal system lifting northward into the
region will bring widespread rainfall through 12Z Thursday, with
precipitation becoming more intermittent/showery thereafter.
Presently seeing VFR conditions at BTV/PBG/SLK, but overall
trend will be toward MVFR overnight, with localized IFR for
MSS/MPV/RUT. Gradual improvement is expected during the daylight
hours on Thursday. Winds will also be an issue overnight...with
gusts to 35kts at RUT through 06Z, and localized LLWS at MPV
through 06Z. Will see winds shift into the SW during Thursday
morning with passage of an occulded front. Winds will be locally
moderately strong at KMSS on Thursday...SW 10-15kt with gusts
Outlook 06Z Friday through Monday...A slow clearing trend is
anticipated with IFR conditions becoming MVFR on Thursday Night
into Friday. Mainly MVFR will prevail in the mountain TAF sites
and a mix of MVFR/VFR in the valleys through the upcoming
weekend. While drier conditions are expected Sunday and Monday,
low level moisture will likely keep VFR/MVFR clouds around
Sunday, less so Monday.