Area Forecast Discussion
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FXUS61 KBTV 211741
Area Forecast Discussion
National Weather Service Burlington VT
1241 PM EST Tue Feb 21 2017
A weak disturbance and associated ribbon of mid level moisture will
produce scattered light rain showers late in the day across northern
New York. This threat of showers will spread into Vermont
overnight...with a few pockets of light freezing rain possible
in the deeper valleys. Very minimal ice accumulation if any is
anticipated...with temperatures in the upper 30s to mid 40s
today. A big warming trend is expected for most of the week with
more showers anticipated on Thursday Night into the weekend.
.NEAR TERM /THROUGH WEDNESDAY/...
As of 1157 AM EST Tuesday...Not much change regarding dew
points across the area late this morning with dry air remaining
in place. Even upstream dew points are low and have adjusted
temperatures and dew points accordingly as dew points remain low
this afternoon and temperatures do not get as warm given the
increasing cloud cover.
Tonight...soundings show deep dry layer between 925mb and 700mb
becoming saturated as moisture advection occurs on south to
southwest winds. Thinking temps fall early as some evaporational
cooling occurs...but with clouds and developing southerly flow of 10
to 20 knots...especially cpv/slv temps hold mainly in the mid/upper
30s to near 40f most of the night. East of the greens still looking
at some pockets of <0C temps in the protected valley with the
potential for some spotty freezing rain. Given the marginal temps
and scattered precip/very light qpf...not anticipating widespread
coverage of freeze rain and very minor ice accumulation. If needed
will handle with a sps.
Wednesday...low to mid level warm air advection continues with
progged 925mb to 850mb temps climbing between 2c and 4c.
However...soundings especially the nam shows plenty of low level
moisture trapped below thermal inversion between surface and 850mb.
Is this overdone again or do we see lots of low clouds and limited
sun on Weds...keeping our temps on the cooler side of guidance with
some areas of light precip. Soundings show this moisture mixing
out...especially during the afternoon hours as top of the mixed
layer winds increase between 15 and 20 knots and drier air aloft is
advected toward the surface. Will trend toward the warmer side of
guidance and keep forecast mainly dry at this time...with highs
mainly lower 40s northeast kingdom to near 50f cpv/slv and western
.SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY NIGHT/...
As of 358 AM EST Tuesday...Thursday will see another low pressure
system from the Great Lakes region pass to the north of the
CWA. Light showers, mainly in the northern half of the forecast
area, are expected with the system passes north of the border
and into northern Maine. QPF is minimal with this system with
the Adirondacks seeing a couple tenths of an inch, the Northern
Vermont counties seeing around a tenth and the rest of the state
seeing only a few hundreths of an inch.
Southerly flow will continue to boost temps well above seasonal
norms for Thursday with highs in the 50`s for the majority of the
area and overnight lows in the mid to upper 30`s.
.LONG TERM /FRIDAY THROUGH MONDAY/...
As of 358 AM EST Tuesday...Friday sees low pressure tracking north
and west of our region from the Great Lakes Friday through
early Sunday morning. Models are in general agreement of a warm
front lifting through the region Friday afternoon/evening with
precipitation ramping up through the day Saturday with the peak
Saturday afternoon/evening just ahead of the passage of a cold
front. Winds out ahead of the front could lead to gusty
conditions and potential advisory level winds especially across
the Champlain Valley as the 00Z GFS indicates 850mb winds to
reach 65 knots Saturday afternoon. After frontal passage, rain
will switch over to snow showers Saturday night with the strong
cold air advection. Very warm temperatures are expected Saturday
ahead of the cold frontal passage. Temperatures overall look to
be in the 50s with the Champlain Valley pushing a record
breaking 60. A sharp cold front will drop temps quickly back
into the 20s Saturday night. Possible flash freeze issues are
possible with temperatures dropping so sharply after a moderate
rainfall. Moving into next week, more seasonable weather will
return for Sunday through Tuesday.
.AVIATION /18Z Tuesday THROUGH Sunday/...
-- Changed Discussion --Through 18z Wednesday...VFR conditions persist through this
evening as dry low levels make it more difficult for
precipitation reach the ground this evening and overnight.
Therefore have VCSH at all TAF sites. Expect moisture and
possible light showers to move from NW to SE affecting terminals
in the North Country from 00Z Wednesday through 06Z.
Cannot rule out light freezing rain possibilities at KSLK mainly
MVFR conditions possible at KMSS/KSLK after 06Z through mid
morning. KPBG/KBTV MVFR possible during the early to mid morning
Gusty winds channeling up the Champlain Valley subside this
evening but generally remain above 10kts through 06Z. Southerly
winds continue at 5-10kts for Wednesday.
Outlook 18z Wednesday through Sunday...
Wednesday - Thursday...vfr/mvfr with pockets of mvfr/ifr in our
Friday - Saturday...A warm front lifting from southwest to
northeast on Friday will produce additional showers along with
some enhanced southerly winds. The turning wind profiles and
rapid increase in speed with height will cause some areas of
turbulence and shear on Friday Night into Saturday. Widespread
gusty southerly winds likely on Saturday with areas of rain
showers...producing localized mvfr/ifr cigs/vis in the heavier
Sunday...VFR/MVFR conditions possible, especially in mountains
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