Area Forecast Discussion
Issued by NWS Burlington, VT
FXUS61 KBTV 271514
Area Forecast Discussion
National Weather Service Burlington VT
1014 AM EST Mon Feb 27 2017
Local water levels continue to recede as cooler temperatures
prevail and runoff decreases. Starting the work week expect
quiet and mild conditions. Periods of rain with well above
normal temps return Tuesday into Wednesday which could produce
more hydro impacts given our above normal stream flows. Much
cooler air arrives by the end of the week...along with chances
for mainly mountain snow showers.
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
As of 1010 AM EST Monday...Current forecast on track and little
change made. 12z ALY/BUF soundings shows airmass well mixed to
above 850 mb with 850 temps -4 to -5 deg C supporting MaxT of
mid to upper 40s possible in the valleys and lower 40s mtns
under mainly partly cloudy skies. Still expecting a breezy to
windy day with gusts around 30 kts.
Previous discussion...Current forecast in good shape with temps
continuing to hold steady or slightly rise as day break occurs.
Gusty winds are setting in across the forecast area as the
steep lapse rates are mixing well and mean boundary layer flow
based on KCXX VAD wind profiles shows around 30 kts in the
lowest 2000 ft of the atmosphere.
As opposed to the active start to the weekend, the start of the
work week will be quiet and mild. High pressure departs to our
east as mid level clouds continue to build into the North
Country. An upper level disturbance will track to our north
which could bring enough moisture to see some mountain snow
showers late in the day. Otherwise we will be looking at partly
cloudy skies with warm air advection continuing. 925mb temps
warm to -1C to +2C supporting max temps in the mid to upper 40s
today. Overnight the warm advection continues and as the winds
turn calm expect a very shallow inversion to develop as
radiational cooling will drop our overnight lows to the upper
20s to low 30s.
A moderate low level 850mb jet will push across the North
Country this afternoon and with steep low level lapse rates we
should see a well mixed pbl. Bufkit soundings from our 2km and
4km wrf show the mean boundary layer flow in the in 20-30kt
ranges. Using that as a proxy for our gusts today we should see
fairly gusty winds across the North Country this afternoon.
Lapse rates weaken by early evening and thus the winds will as
well. Overnight the boundary layer decouples and we should see
fairly calm winds.
.SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY/...
As of 338 AM EST Monday...West to southwest flow aloft aloft
will develop over the area through the entire period. This will
lead to temperature and moisture advection and we will once
again see above normal temperatures through the period. Highs on
Tuesday will be in the mid 40s to lower 50s and in the mid 50s
to lower 60s on Wednesday. With the temperatures on Wednesday...
there will likely be some more record highs set. Of note will
be the lows Tuesday night...which will be above freezing. So we
will once again have an extended period of conditions favorable
for more ice breakup in rivers plus new snowmelt. Showers will
be off an on during the period...especially Tuesday night into
Wednesday. Standardized anomalies for precipitable water will be
three times higher than normal...so will need to keep an eye on
potential precipitation amounts. At this time we could be
looking at a half inch to three quarters of an inch in the
Tuesday through Wednesday night time period.
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
As of 338 AM EST Monday...Upper trough will be moving across
the area Wednesday night into Thursday and will be bringing an
end to the precipitation from west to east. Temperatures will
also be falling and we will be trending toward below normal
temperatures as we head to the weekend with northwest flow aloft
becoming established over the region. Drier air will also be
moving in and precipitation chances will be pretty small as a
result with temperatures cold enough for precipitation to be in
the form of snow showers.
.AVIATION /15Z Monday THROUGH Friday/...
Through 12Z Tuesday...A weak ridge of high pressure will pull
east of the region during the morning hours today. Expect VFR
conditions to prevail through TAF period. Only aviation concern
will be the gusty pressure gradient winds across the region
today. With steep lapse rates and decent mixing expect gusts of
20-30kts at most TAF sites through the afternoon. The low level
jet at 850mb will likely cause some issues with wind shear and
low level turbulence especially over northern New York, but
with the gusts mentioned in the TAF`s I opted to not include any
mention of LLWS in the TAFs.
Outlook 12Z Tuesday through Friday...
12Z Tuesday - 18Z Tuesday...VFR conditions.
18Z Tuesday - 06Z Thursday...Scattered/numerous rain showers
with variable cigs from VFR to IFR depending on time period as
low pressure crosses the region.
06Z Thursday onward...Scattered snow showers/flurries and
occasional MVFR/IFR conditions early trend mainly VFR after 18Z
As of 320 PM EST Sunday...Most rivers have crested with latest
hydro graphs showing water levels receding...therefore the
flood watch has been cancelled. See local flood statements for
latest crest information on our web page.
We continue to watch Tuesday afternoon through Weds time period
closely for the potential for additional river rises associated
with several rounds of showers and embedded downpours. This
expected rainfall along with much above normal temperatures will
result in additional snow melt and the potential for sharp river
rises...especially given the already high levels. The good news
is that most river ice is gone and our areal coverage of deep
snow pack is much less than previous event...resulting in less
runoff potential. We will continue to monitor for potential
We could see some records broken on Wednesday based on our
forecast high temperatures. Current records for March 1st are
Burlington - 59 set in 1954
Montpelier - 53 set in 1991
St. Johnsbury - 58 set in 1954
Massena - 49 set in 1954