FXUS61 KBTV 230502
AREA FORECAST DISCUSSION
National Weather Service Burlington VT
102 AM EDT Tue Apr 23 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 /UNTIL 2 PM THIS AFTERNOON/...
As of 1256 AM EDT Tuesday...Updated to increase pops across
eastern sections of vt for several more hours, as radar and sfc
obs show light rain continues from near 1v4 to ludlow. Expecting
areal coverage of precip to decrease shortly as sfc low pres
near Cape Cod shifts northeast off shore. Otherwise, temps are
highly variable tonight, with slk already 2 degrees below
anticipated low forecast, so have made some adjustments to hrly
temps and overnight lows to match crnt conditions. Thinking lows
range from mid 30s slk to mid/upper 40s warmer valleys.
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 /2 PM THIS AFTERNOON 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 /06Z TUESDAY THROUGH SATURDAY/...
Through 06Z Wednesday...Weak ridge is providing our taf sites
with vfr conditions this morning, as rain/lower cigs associated
with coastal system is east and next low pres is approaching
from our west. Expecting mainly vfr conditions to prevail today
with trends toward mvfr cigs at mss/slk toward 00z Weds. Rain
showers will develop across the SLV by 00z and quickly spread
into the northern dacks/cpv btwn 00-03z Weds, with cigs trending
toward ifr conditions possible at slk by 06z Weds.
North/northeast winds this morning will shift to the south by
this aftn and becoming breezy at times this evening as the rain
is arriving, especially btv/slk/rut/mpv.
Tuesday Night: Mainly VFR, with areas MVFR possible. Windy with
gusts to 30 kt. Definite RA, Likely SHRA.
Wednesday: Mainly VFR, with areas MVFR possible. Chance SHRA.
Wednesday Night: Mainly VFR, with areas MVFR possible. Chance
Thursday: VFR. NO SIG WX.
Thursday Night: VFR. Chance SHRA.
Friday: VFR/MVFR conditions possible. Likely SHRA.
Friday Night: Mainly MVFR, with local IFR possible. Chance SHRA.
Saturday: Mainly VFR, with local MVFR possible. Slight chance