Area Forecast Discussion
Issued by NWS Burlington, VT-- Highlight Changed Discussion --
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FXUS61 KBTV 221737
Area Forecast Discussion
National Weather Service Burlington VT
137 PM EDT SUN MAY 22 2016
Scattered showers will be possible this afternoon as a low
pressure system off the coast of the DelMarVa peninsula slowly
pushes northeast towards the New England coastline. Temperatures
will be near normal to end the weekend and then trend warmer by
the middle of the work week.
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
-- Changed Discussion --As of 123 PM EDT Sunday...No changes to this near term portion.
Forecast continues to track well with current conditions. Morning
sprinkles have dissipated and moved on, with new afternoon
convection forming in Northeast Kingdom of Vermont where sun broke
out this morning with surface instability. LAPS surface based CAPE
up to 500-700 j/kg, with little if any cap. Precip moving in an
odd southwesterly direction with closed upper low to southeast
providing the steering flow. Some lightning noted in storms over
NH but for the most part only showers. Current pops/weather
forecast has this handled well so no chances there.
Temps warming into the upper 60s/low 70s as forecast and no
Overnight tonight weak surface front will push on through the
region and and 500 mb low continues to cut off and sag to the
south. Ridge of high pressure to build in from the west at surface
and aloft, and subsidence to allow for some clearing skies and
light winds. Fog formation possible tonight especially in areas
where rainfall today will moisten up the boundary layer. With good
radiational cooling min temps to drop back into the upper 40s/low
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.SHORT TERM /6 AM MONDAY MORNING THROUGH TUESDAY/...
As of 237 AM EDT Sunday...Vertically stacked low pressure system
drifts east of the Delmarva peninsula during the day Monday, with
newd extending trough along the New England coast remaining in
place. It appears that overall movement/shift of this system to
the east will allow for drier air to advect into the North Country
on northerly low-level flow. As such, only included a slight
chance of showers across Rutland/Windsor counties for Monday
afternoon. Partly to mostly sunny skies (more sun north) along
with 850mb temps around +10C will yield pleasant afternoon temps
with highs 74-78F in most areas...and dewpoints dropping into the
mid-upr 40s for much of the northern 2/3rds of the region.
The vertically stacked low pressure system begins a slow northward
turn later Monday night, reaching an area east of NJ by daybreak
Tuesday. This should result in increasing mid-upr level cloud
cover across central and s-central VT during the overnight period
Monday night. Maintained just a slight chance of showers across
Orange/Windsor/Rutland Counties on nrn periphery of this system.
Increasing clouds across VT will keep lows on the mild side,
generally in the lower 50s. May see some mid-upr 40s across nrn NY
where thinner and less extensive cloud cover is forecast.
The closed 500mb low tracks nnewd across sern MA on Tuesday.
System is equivalent barotropic in nature, and likely will be
associated with bands of showers around the w/nw periphery rather
than broader zone of stratiform precipitation. Have included PoPs
40-60 percent attm, with precipitation amts 0.1-0.2" for most
sections of VT, with lighter amts across nrn NY further removed
from the low center. May see some locally heavier amts given PW
values reaching 1.2" per 00z GFS, and potential instability around
500 J/kg leading to a few embedded tstms. Some of the tstm
potential for depend on overall extent of clouds and whether or
not PBL heating/destabization can occur across the region. We will
continue to monitor. Deep layer NE flow would result in slow w-sw
storm motions if embedded convection were to develop. Highs on
Tuesday generally expected in the low to mid 70s.
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
As of 237 AM EDT Sunday...Upper low departs east of New England on
Wednesday, resulting in drier conditions and a transition toward a
warmer and more humid overall weather pattern for the bulk of the
extended forecast period. There has been an increase in run-to-run
variability in the GFS and ECMWF...making daily details a bit
uncertain. Anticipate highs Wednesday in the mid-upr 70s with just
a slight chance of a late aftn/eve shower. Building heights and
strengthening SW low-level flow should yield highs into the lower
80s for some valley locations Thursday/Friday/Saturday. Will
likely also see a gradual increase in humidity with dewpoints
getting into the lower 60s by Friday into Saturday. With air mass
becoming more moist/unstable, PoPs continue generally 30-40% each
.AVIATION /18Z Sunday through Friday/...
-- Changed Discussion --Through 18Z Monday...VFR with scattered showers and possibly a
thunderstorm mainly central and southern Vermont this afternoon,
then patchy IFR visibility in fog in mountainous TAF sites during
early morning hours. rain showers forming in instability in
northeast Vermont where sunshine has broken out, and are tracking
southeast ahead of a slow moving surface front. Potential for MVFR vis
and VFR cigs in the showers, however kept all VFR in actual TAFs.
Showers to dissipate with loss of surface heating, then clearing
skies. KMPV and to a lesser extent KSLK will have some residual
moisture from afternoon showers combined with radiational cooling
to produce some IFR fog in the 07-12z timeframe. Conditions
improve to VFR clear after 12z.
Outlook 18Z Monday through Friday...
18z Mon - 12z Tue: VFR/high pressure
12z Tue - 12z Thu: VFR with chance of afternoon showers Tuesday
and Wednesday with brief MVFR visibility restrictions.
12z Thursday - Friday: VFR/high pressure.
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