FXUS61 KBTV 222248
AREA FORECAST DISCUSSION
National Weather Service Burlington VT
648 PM EDT Mon Apr 22 2019
A weak low pressure system will move just to the east of Cape Cod
this evening and bring some rain showers to far southeastern and
eastern Vermont through the overnight hours. This low will quickly
track to the northeast and rainfall will end by Tuesday morning.
Tuesday will be another beautiful spring like day with temperatures
warming back into the mid 60s to lower 70s under partly cloudy
skies. A cold front will then sweep across the North Country Tuesday
night into early Wednesday morning with widespread rainfall amounts
around a quarter of an inch with up to half of an inch for western
facing slopes. Temperatures will then return to near normal
temperatures through the remainder of the week and into the weekend.
The next chance of rainfall won`t come until Friday when another
cold front moves through the North Country.
.NEAR TERM /THROUGH TUESDAY NIGHT/...
As of 625 PM EDT Monday...Quick update to the evening forecast
to adjust sky cover and pops. Latest radar and satellite trends
show precip is having a hard time moving westward into the mid-
level ridge located over the eastern Great Lake and northern New
York. Meanwhile, some mid-level clouds riding over said ridge
are encroaching upon the St. Lawrence Valley from the northwest.
Adjustments to the forecast were to taper back pops across
eastern Vermont to mainly chance with only a brief window of
likely showers near Springfield VT, and lower cloud cover across
central areas before approaching mid clouds spread eastward
overnight. Temps remain on track for Tuesday morning lows
ranging through the 40s.
Previous Discussion...It has shaped up to be another beautiful
spring day across the North County with decent shortwave ridging and
a surface trough building in from the west. Increasing subsidence
associated with these features has helped keep diurnal cumulus under
control even though temperatures once again have warmed into the
lower 60s to lower 70s. The moisture plume that was prevalent last
night and early this morning has shifted east with main moisture
axis now over central and eastern Maine. After watching the
formation of a surface low off the Virginian coast, it looks like it
will track slightly further east than previously forecasted and take
it right over or just east of the benchmark. With the system being
very compact, it looks like most of the rainfall will fall east of
the Connecticut River during the overnight hours. However, it could
still clip extreme southeastern Vermont near Springfield and drop a
quarter of an inch of rain. There will be an impressive gradient in
rainfall amounts so any further eastward deviations could lead to
most, if not all, of Vermont remaining on the dry side tonight. With
ample cloud cover expected to redevelop tonight, lows will once
again be above normal with readings in the upper 30s to mid 40s.
Tuesday will start off as another nice day with the aforementioned
ridging shift directly overhead. Highs will easily climb back into
the mid 60s to lower 70s under partly sunny skies and light
northerly winds. However, an developing upper level trough will
become negatively tilted through the day on Tuesday and begin to
push across the North Country starting Tuesday Evening. A decent jet
streak will develop on the eastern side of the trough as it moves
through the region which will help produce some enhanced upper level
support and drive a cold front through the region. In addition, a
nice band of frontogenesis will be present at both the 925 mb and
850 mb layers, albeit slightly offset. The increased low level and
upper level support should yield a period of nice rainfall as the
cold front pushes through Tuesday evening and Tuesday night.
Rainfall totals for the most part look to be around a quarter of an
inch but the western slopes of the Green and Adirondack Mountains
could see as much as half of an inch of rainfall. Thunderstorms look
unlikely given the timing of the front and lack of surface and mid-
level instability which should inhibit any one location from seeing
locally higher amounts of rainfall.
.SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/...
As of 253 PM EDT Monday...Shortwave trough pulls through the
region during Wednesday, then exits east by Wednesday night
under a near seasonal late April airmass. With moist cyclonic
flow in place, plenty of clouds will be the rule during the
daylight hours which will tend to scatter out overnight into
Thursday morning. Highest coverage of scattered showers will
occur across the northern mountains on Wednesday where some
orographic enhancement will be likely in closer proximity to the
associated mid level cool pool. QPF will remain light however.
By Wednesday night conditions trend largely dry as heights build
on the northern end of Mid Atlantic high pressure.
.LONG TERM /THURSDAY THROUGH MONDAY/...
As of 253 PM EDT Monday...An active pattern continues into late
week with brief high pressure on Thursday giving way to another
digging shortwave trough and showers by Friday. Additional
energy may or may not affect the area once again by later in the
weekend but timing and placement differences among medium range
solutions give pause to getting too certain at this point given
fast westerly flow aloft. The troughing with the Friday system
is a little more robust than the mid-week feature, so highest
PoPs (50- 70%) will be offered at this point with a trend toward
a slightly cooler regime from Saturday onward.
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
Through 00Z Wednesday...A squeeze play across our area for the
next 24-36 hours with eastern VT witnessing some light
rain/showers from coastal while a cold front approaches western
areas by late in the day Tuesday. Pretty much VFR with mid cloud
deck exceppt KRUT and KMPV could see a shower or two through
the overnight hours, it looks like ceilings will stay at 4000 ft
or greater. Ceilings will improve once again Tuesday morning
ahead of an approaching cold front with north to northwest winds
of 10 knots or less.
Tuesday Night: Mainly VFR, with areas MVFR possible. Definite
Wednesday: Mainly MVFR, with areas VFR possible. Chance SHRA.
Wednesday Night: Mainly VFR, with local IFR possible. Chance
Thursday: Mainly VFR, with local MVFR possible. Chance SHRA.
Thursday Night: VFR. Chance SHRA.
Friday: Mainly VFR, with areas MVFR possible. Likely SHRA.
Friday Night: Mainly VFR, with local IFR possible. Chance SHRA.
Saturday: Mainly VFR, with areas MVFR possible. Chance SHRA.