Area Forecast Discussion
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FXUS61 KBTV 282028
Area Forecast Discussion
National Weather Service Burlington VT
428 PM EDT SAT MAY 28 2016
The Memorial Day weekend will continue to see well above normal
temperatures with daytime max temps between 10 to 20 degrees
above normal. Increasing low level moisture will allow for higher
relative humidities and an increasing chance for widespread
showers with scattered thunderstorms possible on Sunday and
.NEAR TERM /THROUGH SUNDAY/...
As of 344 PM EDT Saturday...
With the 2pm observation in Burlington we reached 90 degrees for
the second day in a row putting us two thirds of a way to a local
heat wave. Expect warm and muggy (relative to normal for the North
Country) conditions through the rest of the afternoon and early
evening. The scattered cumulus field has continued to develop
across both northern New York and Vermont, however the lack of
any significant forcing has prevented any showers from developing
as of this discussion. The lake breeze on the western edge of Lake
Champlain may end up being the trigger for some late afternoon
early evening convection depending on how inland it moves.
Additionally, the western edge of the Champlain Valley has been
considerable cooler with light to moderate onshore flow from the
much colder lake water temps. With the area somewhat unstable
150-200 J/kg of MUCAPE any showers that do develop will have the
potential to cause an isolated lightning strike or two.
As the upper level ridge continues to build this evening expect
another evening with some potential for patchy fog development. The
best chance will be over northern New York where we are still
drying out from the light rain that fell overnight Thursday.
Across Vermont where we`ve gone with consecutive drys days we may
not have enough boundary layer moisture to see widespread fog.
Tomorrow, as mentioned by the midnight crew, becomes quite the
active period. The upper level ridge overnight gives way to an
advancing upper level trough. There will be a large influx of
precipitable water with values rising to 1.6-1.8 by location.
925mb temps are elevated again Sunday and the 21-23C 925mb temps
will support max temps tomorrow once again in the upper 80s to low
90s. Currently the forecast for Burlington reaches heat wave
criteria with a max temps of 90 expected. Unlike today however
there will be a few piece of shortwave energy the ride along the
longwave trough providing the necessary trigger for convection to
occur. So I`ve continue to offer high chance to likely pops for
most of the forecast area. MUCAPE values are expected to exceed
500-1000 J/kg and K-index values also are indicated of
thunderstorm development. With the chance for thunderstorm
development, slow storm motions, and abnormally high pwat, I
continued to mention the chance for heavy rain in any
thunderstorms that develop. We should be safe with regards to
flash flooding due to how dry we`ve been in May but caution should
be taken with any shower producing heavy rainfall.
.SHORT TERM /SUNDAY NIGHT THROUGH MONDAY NIGHT/...
As of 427 PM EDT Saturday...precipitable water values early
Sunday night will be 1.5 to 2 inches. Will mention showers and
thunderstorms for Sunday night, and will include some heavy
rainfall possible with any thunderstorms. Conditions quite dry
across the region in May, so do not expect any flash flood issues
at this time. ECMWF and GFS models now showing frontal system will
move through the region earlier in the day on Monday with showers
mainly Monday morning, as both models showing a mid level dry slot
will move into the region by 18z Monday. Thus, have decreased pops
for Monday afternoon, and will go with a dry forecast for Monday
.LONG TERM /TUESDAY THROUGH SATURDAY/...
As of 427 PM EDT Saturday...Fair and dry weather will be over the
north country from Tuesday through Thursday night, as a ridge of
high pressure at the surface and aloft builds east from the Great
Lakes. ECMWF and GFS models in fairly good agreement with bring a
cold front from the Great Lakes into the region with showers
expected Friday and Friday night. ECMWF and GFS models differ on
forecast for Saturday, with the ECMWF model more progressive than
the GFS and has a mainly dry forecast for Saturday, while the GFS
model has the front stalled across the region on Saturday as it
will be parallel to the upper flow. Thus, forecaster confidence
for the Saturday forecast is low at this time. Have stuck with
super-blend pops for Saturday and will have a chance of showers in
the forecast for Saturday.
.AVIATION /20Z Saturday THROUGH Thursday/...
Through 12z Sunday...Generally VFR conditions through the TAF
period...with SCT mid-upper level clouds. Light fair weather
cumulus has begun to pop up over the adirondacks with an isolated
showers or thunderstorm possible. Areal coverage is minimal so
I`ve only included vcsh for PBG which has the best chance to see a
shower in the vicinity this afternoon. Generally calm to light
and variable winds will continue this afternoon before going calm
overnight and then southerly tomorrow morning.
Outlook 12z Sunday through Wednesday... Mainly VFR with a daily
chances for showers and thunderstorms each afternoon and evening.
Greatest coverage/threat appears to occur in the Sunday and Monday
time frame. Best chance for a dry day will be Wednesday.
Record maximum temperatures for Saturday 5/28 and Sunday 5/29 are as
BTV - Burlington 92 in 1978 89 in 1978
MPV - Montpelier 88 in 1978 87 in 1978
MSS - Massena 89 in 1978 90 in 1978
St Johnsbury 93 in 1978 92 in 1978
Mt Mansfield 77 in 1978 77 in 1978