Area Forecast Discussion
Issued by NWS Burlington, VT-- Highlight Changed Discussion --
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FXUS61 KBTV 261845
Area Forecast Discussion
National Weather Service Burlington VT
245 PM EDT Fri Aug 26 2016
-- Changed Discussion --Fair and seasonably warm weather will prevail across the region into
Sunday as high pressure dominates the sensible weather pattern. The
next chance for scattered showers will occur by later Sunday into
Sunday evening as a weak front crosses the area. Behind this system
a return to fair and dry weather is expected for early next week.
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.NEAR TERM /THROUGH SATURDAY/...
-- Changed Discussion --As of 245 PM EDT Friday...A quiet 24-hour stretch of weather is
expected across the area as surface high pressure across southern
Canada combines with deep subtropical upper ridging over the
southeastern states to provide broad-scale subsidence and mainly
clear skies. Other than some patchy mist/fog across favored
locales later tonight skies should be mainly clear through the
period with no rain expected. Temperatures generally a blend of
bias-corrected model output offering overnight lows in the 50s to
near 60 and highs on Saturday from 78 to 85 or so under moderate
humidity levels. Winds light.
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.SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY/...
As of 307 AM EDT Friday...Latest trends show system for Sunday
arriving several hours earlier associated with fast westerly flow
aloft. Otherwise...Saturday expect mostly sunny skies with comfortable
temperatures and humidity values. I anticipate scattered fair weather
cumulus clouds to develop over the terrain as temperatures climb
into the mid 70s to lower 80s depending upon elevation. Light
north/northwest winds will shift to the south/southwest by
Saturday Night. On Sunday...first ribbon of enhanced 700 to 500mb
moisture associated with weak mid level warm air advection will
shift from southwest to northeast across our region. Expect maybe
a few sprinkles...as moisture will have tough time reaching the
ground...given dry profiles. Deeper moisture and better dynamics
arrive after 18z...along with weak surface boundary in the flow
aloft. This energy/moisture will produce additional scattered
showers on Sunday afternoon/evening with maybe a few rumbles of
thunder. Overall...instability is limited with CAPE values <500
J/kg and forcing is weak with energy getting sheared out in the
fast westerly flow aloft. I will continue to mention chance pops
with main focus over the mountains and after 18z Sunday. Progged
850mb temps warm to 16c ahead of boundary...but clouds may keep
values in the upper 70s to mid 80s...very similar to yesterday
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
As of 307 AM EDT Friday...Overall models are in good agreement
with large scale pattern across our region for next week. This
features a developing trof across the western and eastern conus
with high amplified ridge in the middle. Temperatures will be
above normal to start...but trend below normal by late next
week...with even the 0C 850mb isotherm progged to make an
appearance off both the latest 00z ECMWF/GFS. Some people are
excited about the arrival of cooler weather and are looking
forward to the upcoming winter months already.
For Sunday Night into Monday will continue to mention chance pops
with narrow ribbon of enhanced moisture and short wave energy
diving across our region with surface boundary. A rumble or two of
thunder is possible...especially northern NY around 00z.
Otherwise...qpf will once again be light and generally <0.25 with
this system. Surface high pres and weak cold air advection
develops for Monday into Tuesday with general dry conditions and
slightly above normal temps. The lack of a deep trof and limited
cold air advection behind boundary...supports only minor changes
in our thermal profiles for early next week.
Toward the end of next week a series of short waves and associated
cold front will help to carve out a deeper mid/upper level trof
across the ne conus. This support a gradually cooling trend in the
temps...with chances for scattered showers. The developing
northwest upslope flow supports the highest pops over the
mountains...especially Thursday into Friday. Progged temps start
near 15c for Tuesday...but cool to 10c by Thursday and single
digits by 12z Friday with brisk northwest winds. I will mention
temps in the 80s Tuesday...70s by Thursday...and 60s by next
Friday...with lows gradually cooling into the upper 30s to lower
50s depending upon elevation and vicinity to the warmer lake
.AVIATION /19Z Friday THROUGH Wednesday/...
Through 18Z Saturday...VFR through the period with mainly scattered
cumulus bases in the 035-045 AGL range through 00Z, then SKC.
Patchy IFR/LIFR br/fg possible at KMPV/KRUT/KSLK in the 06-12Z
time frame tonight. Mixed signals on potential br/fg occurrence
given dry advection regime with MOS-based guidance most bullish.
Confidence moderate on occurrence but given morning rainfall, at
least some added low level moisture input will be present
overnight with light winds aloft. Winds generally light west to
northwesterly 5-10 kts through 00Z, then light and variable
Outlook 18Z Saturday through Wednesday...
18Z Saturday through Wednesday...mainly VFR through the period
with high pressure. Two main threat periods for scattered showers
and brief MVFR conditions - Sunday afternoon/evening, then again
Tuesday afternoon/evening with weak trough passages.