Scientific Forecaster Discussion
fxus61 kbtv 222026
Area forecast discussion
National Weather Service Burlington Vermont
326 PM EST Fri Nov 22 2019
gusty winds and showers will gradually come to an end
tonight as high pressure builds into the region. With high pressure
remaining over the area on Saturday dry weather will continue...but
high temperatures will be a few degrees below normal. A low pressure
system passing to our south late Saturday night into Sunday will
spread some light rain and light snow into the area. Any snow
accumulations will be light and mainly confined to southern and
Near term /through Saturday night/...
as of 326 PM EST Friday...band of showers will continue to move
across the northern half of Vermont and Essex County New York
this afternoon...but exit the area shortly after sunset. Showers
are mainly in the form of rain...but some spots cold enough for
snow and snow squall parameter doing a good job showing
favorable conditions for these showers. Again...mostly rain
showers and not having the same impact as if they were snow
showers. Gusty west to northwest winds continue to develop this
afternoon and will continue through the evening hours. Still
feel gusts will mainly be in the 25 to 35 mph range with a few
gusts to 40 mph...but depth of dry adiabatic lapse rates not
steep enough to tap into stronger flow aloft. Eventually the
lapse rates stabilize later tonight and flow aloft becomes
weaker for winds to taper off later tonight. More noticeable
clearing takes place after midnight tonight with lows generally
in the mid teens to mid 20s.
High pressure will be over the area on Saturday and dry weather is
expected. Should see a bit more sunshine as well with highs in the
30s to around 40. Saturday night begins dry and then clouds will be
on the increase along with the chance for some light snow during the
early morning hours on Sunday. Southern and eastern areas of Vermont
seem to be the area mostly likely to see the light snow as main
system producing the precipitation remains well to the south and is
rather progressive. Somewhat better chance to see light snow across
parts of the area on Sunday.
Short term /Sunday through Sunday night/...
as of 326 PM EST Friday...the main feature to watch during the
short term portion of the forecast is an intensifying coastal
low pressure system tracking northeastward off the New England
coast. Models are beginning to converge on a near-benchmark (40n
70w) track of the system after much wider track uncertainty
yesterday. However, still some question as to how far north and
west wrap-around precipitation reaches...making for some
continued uncertainty in our precip forecast for Sunday. Have
kept most of northern New York and and northern Vermont mainly dry
during the day Sunday, but continued with the 40 to 60 percent
pops in southern and eastern Vermont given the closer proximity
to the system. Sunday's temperatures will be relatively warm,
rising into the mid to upper 30s to even low 40s. Could see some
lowering temperatures as wet-bulbing occurs at precip onset,
but overall will still be warm enough to support at least a
rain/snow mix by Sunday afternoon. Thus, overall snow
accumulations in areas that do receive precipitation will be
very limited...under an inch in all but the highest elevations.
Overall a fairly progressive system, and by Sunday night chances
for precip quickly lower. Could see some light snow showers in
higher terrain Sunday night as a weak shortwave moves through,
but accumulations will again be minimal.
Long term /Monday through Friday/...
as of 326 PM EST Friday...ridging builds in to start the work
week Monday and Tuesday, which will allow for a period of
tranquil weather. Temperatures will return to near normal (low
to mid 40s by tuesday), which will be a welcome relief from the
cold that has characterized this past month.
Attention then turns to the next low pressure system set to impact
the area midweek. A low pressure system will lift out of the
Southern Plains and track northeastward somewhere in the vicinity of
the Saint Lawrence valley. This system will bring some
precipitation (at this point looking like mainly rain and snow)
Wednesday through Thursday. In addition, northerly/northwesterly
winds will become quite gusty behind the system as a strong pressure
gradient develops. Cold air advection will also be strong behind
the system, leading to a quick return to below normal temperatures
for the end of the week.
Aviation /21z Friday through Wednesday/...
through 18z Saturday...widespread MVFR ceilings will exist
through at least 00z before areal coverage of clouds begins to
diminish and ceilings eventually become VFR after 06z and remain
there through the end of the period. Visibilities will generally
be VFR...but could see some periods of MVFR through 00z due to
showers. Gusty west to southwest winds will exist through 06z
with gusts as high as 30 knots before tapering off through the
remainder of the period.
Saturday night: VFR. Slight chance snow.
Sunday: VFR. Chance ra, chance snow.
Sunday night: mainly MVFR, with local IFR possible. Slight chance
Monday: mainly MVFR, with areas VFR possible. No sig weather.
Monday night: VFR. Slight chance shsn.
Tuesday: mainly VFR, with areas MVFR possible. Slight chance
Tuesday night: VFR. Chance shra, chance shsn.
Wednesday: MVFR/IFR conditions possible. Likely rain showers.
west to northwest winds at 20 to 30 knots will continue for a
better part of the night. Thus a lake Wind Advisory remains in
effect. Waves of 3 to 5 feet will yield rather choppy
conditions...especially over the eastern portion of the Broad
Lake due to the westerly direction. Wind should slowly taper off
after midnight tonight...but remain in the 15 to 25 knot range.