FXUS61 KBTV 202326
Area Forecast Discussion
National Weather Service Burlington VT
726 PM EDT Sat Oct 20 2018
Below normal temperatures are expected overnight tonight into Sunday
as Canadian high pressure builds into the region. Scattered high
terrain snow showers are possible Sunday morning with dry conditions
elsewhere. Breezy northwest winds will allow for wind chills on
Sunday to drop into the low 20s to near 30. The early part of next
week will see another system move across our area and bring with it
below normal temperatures through Thursday. In addition the threat
for precipitation will increase...especially Tuesday into Wednesday.
Conditions trend drier and warmer toward next weekend.
.NEAR TERM /THROUGH SUNDAY NIGHT/...
As of 726 PM EDT Saturday...Going forecast is in excellent
shape with only a few tweaks to sky cover needed through the
overnight hours. Otherwise, remainder of the forecast is
unchanged at this time.
Previous Discussion...The well advertised series of cold fronts
continues to look on track for tonight and Sunday. Looking at
current satellite imagery, a strong shortwave associated with a
broad upper level trough located over northeastern Ontario will
pass well to the south of our forecast area, and along with it
the best moisture and dynamics. The overall broad upper level
circulation will continue to pivot weaker pieces of energy
across our forecast area, and with them several boundaries which
will provide the focus for colder temperatures and slight
chances for mountain snow showers overnight tonight into Sunday
Current surface observations indicate that the first of two cold
fronts has crossed our area with many locations reporting westerly
winds between 10-15 mph. These winds will shift to the northwest
between 00-06z as our next upstream boundary moves across the area.
This surface front will allow temperatures to drop into the low to
mid 30s for valley locations and into the mid to upper 20s across
the Adirondacks and eastern VT Saturday night. 925 mb
temperatures associated with this air mass are between -3 and -4
degrees C and will keep daytime temperatures on Sunday in the
low 30s to near 40 for much of the area. Expect the broad river
valleys to warm into the mid to 40s, however brisk north-
northwest winds will allow for wind chills in the low 20s to mid
With 10-15 mph northwest winds, a few mountain snow showers may be
possible early morning Sunday, however with limited low level
moisture only expecting a light dusting on the highest peaks. The
remainder of the day Sunday looks dry heading into the overnight
period. Sunday night will be the coldest night of the weekend with
temperatures generally in the mid 20s to near freezing in the
Champlain valley. Clouds and gradient winds will be around overnight
Sunday into Monday so despite cold temperatures, not expecting
things to completely bottom out as some model guidance suggests. At
this time have included the possibility for some patchy frost
between 06-11z Monday, but we will continue to monitor these trends
over the next 24 hours as the growing season has not ended yet for
the Champlain valley.
.SHORT TERM /MONDAY THROUGH MONDAY NIGHT/...
As of 403 PM EDT Saturday...High pressure exists over the area
Monday morning and then shifts east during the period. Low level
southwest flow will develop and should set up some lake effect
showers off of Lake Ontario Monday afternoon into night.
Northern New York and the northern half of Vermont will have the
best chance to experience these showers. Temperatures will be
warm enough in the low levels during the day on Monday for the
precipitation to be in the form of rain...but mountain location
Monday night will have the chance to see some snow showers.
Highs on Monday will generally be in the 40s with lows Monday
night in the 30s to around 40.
.LONG TERM /TUESDAY THROUGH SATURDAY/...
As of 403 PM EDT Saturday...Upper trough becomes established
over the Northeast Tuesday into Wednesday with sufficient
synoptic scale forcing for more widespread precipitation across
northern New York and Vermont. Temperatures will be warm enough
on Tuesday for rain showers but we will start to trend toward
rain showers and mountain snow showers on Wednesday. Northwest
flow aloft becomes established Wednesday night and Thursday and
this will bring colder and drier air into the region. Below
normal temperatures will be the rule for the rest of the week
with a slow warming trend heading into the weekend.
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
Through 00Z Monday...VFR conditions are generally expected
through the next 24 hours with the exception being a brief
period of MVFR ceiling at KSLK from 08-14Z. Mid/high clouds
currently streaming into the region from the southwest will
gradually shift southeast overnight with upstream SCT/BKN slowly
entering the region Sunday, but remaining VFR. Winds WSW
5-10kts tonight shift to the NW Sunday at 5-15kts with some
gusts up towards 20kts.
Sunday Night: VFR. NO SIG WX.
Monday: VFR. Slight chance SHRA.
Monday Night: Mainly VFR, with local MVFR possible. Chance SHRA,
Tuesday: Mainly VFR, with areas MVFR possible. Likely SHRA.
Tuesday Night: Mainly MVFR, with local IFR possible. Chance SHRA,
Wednesday: Mainly MVFR, with local IFR possible. Chance SHRA,
Wednesday Night: Mainly VFR, with areas MVFR possible. Slight
Thursday: Mainly VFR, with areas MVFR possible. NO SIG WX.
A Lake Wind Advisory continues through this evening with west
winds at 15 to 25 knots. Eventually they will turn northwest and
decrease to 10 to 20 knots. Waves will continue in the 2 to 4
foot range before decreasing to 1 to 3 feet later tonight.
Choppy conditions will continue through this evening,
especially on the east side of the lake.