Area Forecast Discussion
Issued by NWS Burlington, VT-- Highlight Changed Discussion --
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FXUS61 KBTV 220310
Area Forecast Discussion
National Weather Service Burlington VT
1010 PM EST Tue Feb 21 2017
A low pressure system passing north of the area tonight will bring
light precipitation to the area...generally in the form of light
rain but also area of light freezing rain. The best potential for
any light freezing rain will be in Vermont east of the Green
Mountains with mainly only trace amounts. A noticeable warming trend
takes place starting Wednesday and continues right through Saturday
with above normal temperatures expected. There may be some rain
showers on Thursday...but the best chance for a more widespread rain
will come on Saturday.
.NEAR TERM /UNTIL 7 AM WEDNESDAY MORNING/...
-- Changed Discussion --As of 1010 PM EST Tuesday...As expected, weakening trough
limping across the area this evening with little fanfare other
than a few sprinkles here and there. In fact, I`ve stuggled to
find any mesonet or ASOS site that has actually received
measureable precipitation in our area given very dry boundary
layer air and dewpoint depressions running in the 10 to 20
degree range in most spots outside the northern SLV. Given these
trends have only kept lower chance pops through about midnight,
mainly for eastern counties with any icing threat minimal at
best. Low temperatures still appear on track as clouds and near-
neutral advective processes allow readings to fall only slowly,
bottoming out generally in the lower to mid 30s by sunrise
Wednesday. Have a great night.
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.SHORT TERM /7 AM WEDNESDAY MORNING THROUGH THURSDAY NIGHT/...
As of 320 PM EST Tuesday...Warming trend begins on Wednesday
and continues into Thursday. Highs on Wednesday will be in the
40s and in the upper 40s to mid 50s on Thursday. Not really
looking for any precipitation on Wednesday...but shortwave
trough moving across eastern Canada on Thursday will bring a
chance of showers to the area...but precipitation amounts will
generally be less than a quarter inch. Of note will be the fact
that overnight lows will stay above freezing over much of the
area Wednesday night and Thursday night. This will contribute to
a favorable situation for ice breakup in the rivers that still
have ice and by Thursday we should see an increase in the
potential for ice jams...especially over the northern third of
Vermont and far northeast New York.
.LONG TERM /FRIDAY THROUGH TUESDAY/...
As of 320 PM EST Tuesday...Above normal temperatures will
continue on Friday with highs in the 40s to around 50 and well
into the 50s on Saturday as low and mid level clouds becomes
more south and southwest. This is in response to a more
noticeable upper trough moving into the region on Saturday.
Still looking at widespread rain developing on Saturday and
Saturday night. At this time looking at anywhere from a half
inch to one inch of rain. This combined with the above normal
temperatures should continue to increase the potential for ice
jams and flooding. Situation will be closely monitored as
precipitable water values are anomalously high for this time of
year which could contribute to even more precipitation. Upper
trough moves east of the region on Sunday and quieter weather
returns to the region with highs generally in the 30s.
.AVIATION /03Z Wednesday THROUGH Sunday/...
Through 00z 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. MVFR
conditions possible at KMSS/KSLK after 06Z through mid morning.
KPBG/KBTV MVFR possible during the early to mid morning hours.
Outlook 00z 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
As of 320 PM EST Tuesday...Growing concern for hydrologic
concerns. First item of note is the above normal temperatures on
Wednesday and Thursday with many locations staying above
freezing at night. This should lead to an increased potential
for ice breakup in rivers by Thursday. And this will then
contribute to potential ice jams. Ice is more noticeable in
northern rivers so rivers north of Route 2 in Vermont will have
a better chance for ice jams. The same can be said in northeast
New York for rivers like the Ausable and Great Chazy. Further
warming takes place on Friday and especially on Saturday...which
will contribute to more snowmelt and rises on area waterways.
Upper trough moves into the region on Saturday with above normal
precipitable water values ahead of it and this may contribute
to heavier precipitation across the area. Right now looking at
amounts in the one half to one inch range...but higher amounts
are definitely possible and will continue to monitor. In
summary... growing ice jam threat begins Thursday and continues
into Saturday. Rises in river levels will take place more
noticeably on Friday and Saturday.