Area Forecast Discussion
Issued by NWS Burlington, VT-- Highlight Changed Discussion --
-- Discussion containing changed information from previous version are highlighted. --
FXUS61 KBTV 290239
Area Forecast Discussion
National Weather Service Burlington VT
1039 PM EDT Sun Aug 28 2016
-- Changed Discussion --A cold front will move through the north country overnight with
isolated showers and thunderstorms and will bring cooler and
drier air to the region on Monday. A ridge of high pressure will
build into the region Monday night and will remain through
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.NEAR TERM /UNTIL 6 PM MONDAY EVENING/...
-- Changed Discussion --As of 1038 PM EDT Sunday...Showers and thunderstorms have
diminished to just some isolated activity. Still carrying a 20-30%
PoPs as a cold move south from Canada overnight and early Monday
morning. Expecting low temperatures to be mainly in the 60s
Expecting skies to start out mostly cloudy Monday morning, and
then becoming partly sunny by Monday afternoon as drier air moves
into the region with northwest winds of 10 to 20 mph with some
higher gusts possible. Expecting highs mainly in the 70s on
Monday. There could be some sprinkles Monday morning, but feel
this is isolated, so have not included in the forecast at this
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.SHORT TERM /6 PM MONDAY EVENING THROUGH TUESDAY NIGHT/...
As of 335 PM EDT Sunday...Surface front will be along the New
England coast Monday evening at the start of the short term
period, with 500 mb shortwave trough exiting the coast. Surface
high pressure and shortwave 500 mb ridging over the forecast area
Monday night with dry air. Surface dewpoints fall into the 50s and
1000-500mb mean rh drops below 30 percent. With clear skies and
light winds, good radiational cooling scenario, and lows Monday
night in the mid/upper 40s in the Adirondacks and Northeast
Kingdom, and 50s elsewhere. Will put in some patchy valley fog for
the usual places Monday night as well for potential of radiational
Southerly flow returns quickly Tuesday when high pressure shifts
east of the area, and winds back in advance of next approaching
trough. Dry air also shifts east, and precipitable water increases
tuesday to around 1 1/4 inch, a little above normal. A weak
surface trough will move out ahead of an approaching 500 mb
shortwave trough and provide a focus for showers mainly in the
north Tuesday night. Temps Tuesday in the lower 80s except upper
70s in the Northeast Kingdom of VT and Adirondacks, supported by
850mb temps around 13c. Warmer temps Tuesday night than Monday
night with warmer southerly flow, cloud cover and higher dewpoints
all to limit radiational cooling.
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
As of 335 PM EDT Sunday...Wednesday is a transition day with
ridge over the western US and flat trough in the east. 500 mb low
moving through eastern Canada in northwest flow around the western
ridge. Surface trough pushes on through the area Wednesday and is
focus for afternoon convection, with upper trough lagging by 12
hours or so. Small amount of instability with capes near 500 j/kg.
At this point will continue with just showers and no mention of
thunder. Best chances for rain will be during the day Wednesday,
and lingering Wednesday night over higher terrain in areas favored
by upslope west to northwest low level flow.
Cold front arrives Wednesday night, and upper trough carves out
lower heights. Noticeably cooler and drier Thursday thru Saturday
with nil rain chances for the remainder of the forecast period.
850mb temps near 5-6C supporting max surface temps in the 60s to
around 70 depending on elevation. This will be a few degrees below
their climatological normals for this time of year.
Temperatures rebound late in the weekend with surface high
shifting east for warmer southerly flow on Sunday. Building ridge
in the east raises heights Saturday and Sunday, and 850 mb temps
back to 12-14C, with max surface temps those days in the low 80s.
Will see wide swings in temperatures the last half of the forecast
period with clear skies and warm sunny days, and also clear skies
and light winds at night conducive to good radiational cooling.
Initially lows will be in the 40s and 50s Wednesday night, with a
cooling trend for the remainder of the week. By Saturday morning
patchy frost is possible at Saranac Lake and across the deeper
valleys of the northeast kingdom. For Friday night/Saturday
morning lows will range from the low to mid 30s to upper
40s...except mid 50s near lake champlain. Average 1st frost at SLK
is Sept 7th...so pretty close to normal.
.AVIATION /03Z Monday THROUGH Friday/...
Through 00Z Tuesday...Composite radar loop showing shower and
thunderstorm activity slowly diminishing across the region as of
00Z Monday, due to the loss of daytime surface heating. Expecting
mainly VFR conditions through the period. There could be some
local areas of fog overnight, especially in areas that received
rainfall this afternoon and this evening. Any fog should burn off
by 12Z Monday. Expecting west-northwest surface wind gusts around
20 knots to develop by 14Z Monday and continue til 00Z Tuesday.
Outlook 00Z Tuesday through Friday...
00Z Tuesday through Thursday...mainly VFR through 18Z Wednesday,
as a ridge of high pressure builds into the region. Some areas of
MVFR in scattered rain showers 18Z Wednesday through 00Z Thursday,
as a cold front moves through the region.
Mainly VFR Thursday and Friday, as a ridge of high pressure builds
slowly southeast from Canada.