FXUS61 KBTV 210733
Area Forecast Discussion
National Weather Service Burlington VT
333 AM EDT Tue Mar 21 2023
A weak boundary will produce more clouds today with a chance of
rain and mountain snow showers, with just some minor snow
accumulation possible. Temperatures will warm into the upper 30s
to upper 40s across the region with a few spots reaching near 50
degrees. A quiet weather day is on tap for Wednesday, before
more showers return on Thursday with temperatures warming back
into the 40s to near 50 degrees.
.NEAR TERM /THROUGH WEDNESDAY/...
As of 310 AM EDT Tuesday...Water vapor shows weak embedded 700
to 500mb vorticity moving acrs the eastern Great Lakes with some
enhanced mid lvl moisture. Radar continues to indicate light
rain/snow showers acrs northern NY, but sfc obs and web cams
continue to indicate no precip is reaching the ground, as bl
layer remains pretty dry. Based on this and upstream obs, along
with latest guidance have trimmed back pops/qpf and snowfall
acrs the northern Dacks into the mtns of central/northern VT
today. Best lobe of 850 to 700mb rh and weak embedded 5h vort
slides along the International Border btwn 10z and 16z today,
while best llvl convergence associated with weak cold frnt
arrives aft 18z. Also, minimizing qpf/pops here in the CPV wl be
westerly 850mb wind component of 25 to 35 knots and weak
convergence along sfc boundary. Bottom line have schc/chc pops
valleys to high chc/spot likely in the mtns for a period of time
today, before decreasing activity toward sunset. Any qpf wl be
confined to the higher trrn with values generally <0.10 and just
a minor snowfall accumulation possible above 2000 ft. Temps are
challenging today, as we are starting near 40F here in the CPV,
while east of the Greens in protected valleys are in the upper
teens to lower 20s. 925mb thermal profiles show values ranging
from near -4C northern SLV to +2C southern VT, indicating the
best llvl caa is acrs our northern CWA. Boundary continues to
sink south btwn 16z-20z this aftn with modest llvl caa and winds
shifting to the west/northwest. As a result wl indicate highs
ranging from the mid 30s to lower 40s northern cwa to mid
40s/lower 50s southern valleys today.
For tonight, 1034mb high pres anchored near Hudson Bay tries to
nose into northern NY/VT with some drier bl moisture and
clearing skies. However, boundary that pushes acrs our cwa this
aftn becomes stationary over central NY and slowly begins to
approach our southern cwa with increasing mid lvl moisture by
06z. This axis of moisture and potential impacts on clouds,
along with a sharpening 925mb thermal profiles results in a
tricky overnight low fcst. Based on potential for clearing/lower
dwpts and lighter winds have temps mid/upper teens NEK to lower
30s southern VT/southern SLV for tonight with dry conditions
Weds wl feature above normal temps with developing southerly
flow and moderately strong llvl waa as warm frnt lifts acrs our
cwa. Progged 925mb temps warm btwn 0C NEK to 4 to 6C southern
SLV/Western Dacks and southern VT zns, supporting highs mid 40s
to l/m 50s most locations, while summits hold in the mid/upper
30s. Weak embedded 5h vort and better 850 to 500mb moisture
profiles arrive aft 21z acrs our western cwa, so have continued
with the idea of chc pops toward sunset. Any qpf wl fall in the
form of rain, given very warm bl temps on Weds aftn with amounts
< 0.10 of an inch anticipated. Light and variable winds wl
become south 5 to 10 mph during the aftn hours, as clouds
redevelop from sw to ne acrs our fa.
.SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY NIGHT/...
As of 307 PM EDT Monday...The pattern becomes active again for the
middle of the week, but not until Wednesday night where before that,
surface high pressure and a weak upper ridge will support dry
conditions for Wednesday with highs ranging from the upper 30s along
the international border to around 50 in the lower Connecticut River
Valley. Thereafter, a surface frontal boundary will lift northward
through the region Wednesday night with perhaps some scattered
valley rain and mountain snow showers, but better forcing won`t
arrive until Thursday where shortwave energy ejecting from a
decaying upper trough over the northern plains will ride eastward
along a fast westerly flow aloft and bring numerous rain showers to
the region as the aforementioned warm front sags back south as a
cold front. Right now medium range guidance isn`t in great agreement
with how much QPF we`ll see, but a general tenth to quarter inch
seems reasonable. Showers taper off Thursday night as the front
moves south of the forecast area. Highs Thursday will range through
.LONG TERM /FRIDAY THROUGH MONDAY/...
As of 307 PM EDT Monday...Heading into the end of the work week and
weekend the focus shifts toward the potential for an strong low
pressure system to impact the region over the weekend. Strong
surface high pressure centered over Quebec will bring a partly sunny
and dry day for Friday with highs back to seasonal normals in the
upper 30s to low 40s. But by Friday night, low pressure looks to
develop over the lower Mississippi River Valley and track into the
Ohio Valley by Saturday morning. Thereafter, there is a general
consensus in the long range guidance that this primary low will
continue northward through the Great Lakes Saturday/Saturday night,
while secondary cyclogenesis occurs along the mid-Atlantic coast. As
is to be expected this far out, just how deep this secondary low can
develop and it`s track is highly uncertain, and will play a large
role in the ptype forecast heading into Saturday night and Sunday.
Given it`ll be late March with an increasingly higher sun angle,
surface temperatures will be marginally warm above freezing, but
colder air may persist mid-slope to the summits allowing for a
wintry mix or all snow. At this point, we continue to increase PoPs
as it`s almost a certainty it will precipitate, but we`ll offer up
valley rain and mountain snow for the ptype for starters, but
certainly can`t rule out anything at this time.
.AVIATION /07Z TUESDAY THROUGH SATURDAY/...
Through 06z Wednesday...Mainly VFR conditions expected the next
12 to 24 hours with brief periods of MVFR and low prob chance of
localized IFR at MSS/SLK. Crnt radar shows light precip acrs the
SLV, but sfc obs/web cams indicate no precip is actually
reaching the ground attm. Have utilized tempo for MVFR VIS/CIGS
with light snow mainly acrs our northern taf sites of MSS/SLK
and EFK with just vcsh elsewhere. Any lingering precip should
shift east of taf sites by early aftn, with expected winds shift
to the northwest btwn 5 to 10 knots btwn 17z-20z today. This
developing upslope flow may result in some mvfr cigs at SLK/EFK
and MPV thru the early evening hours, before improving
conditions to VFR is likely.
Wednesday: VFR. NO SIG WX.
Wednesday Night: Mainly VFR, with local MVFR possible. Chance
Thursday: Mainly MVFR, with local IFR possible. Definite SHRA.
Thursday Night: MVFR/IFR conditions possible. Chance SHRA.
Friday: Mainly VFR, with local MVFR possible. NO SIG WX.
Friday Night: Mainly VFR, with local MVFR possible. NO SIG WX.
Saturday: VFR. Likely SHRA, Chance SHSN.