FXUS61 KBTV 171812
Area Forecast Discussion
National Weather Service Burlington VT
212 PM EDT Tue Jul 17 2018
A cold front moving across the North Country this afternoon
will produce scattered showers and thunderstorms. Some storms
will contain localized gusty winds, heavy down pours, and
frequent lightning. Much cooler and drier air arrives tonight on
northwest winds and building high pressure. This trend of
cooler temperatures and lower humidity values will persist for
midweek, before some warmer temperatures arrive by late this
.NEAR TERM /THROUGH WEDNESDAY NIGHT/...
As of 211 PM EDT Tuesday...Cold front now moving into the
Champlain Valley with scattered showers and a few thunderstorms
developing will move south and east this afternoon exiting the
area this evening. Best instability is just ahead of the front
in the Champlain Valley with MLCAPE 800-1500 J/kg and actually
lesser values in southeast Vermont from earlier rainfall. So
best chance for gusty winds and brief heavy rains possible
through about 00z.
Subsidence and drying behind the front in the dry slot seen on
WV with clearing skies and Td dropping into the 50s on westerly
Tonight, moderate low level cold advection develops on
northwest winds of 5 to 10 knots as mid/upper level trof swings
by. The forecast challenge will be if any fog/br can develop,
especially with recent rainfall. Continued with previous
thinking that the combination of gradient winds/mixing and some
clouds overnight will limit widespread fog development. Temps
will range from the upper 40s to lower 60s overnight.
Mid/upper level trof axis will be over head tomorrow with 850
temps cooling to 8-10C along with building high pressure.
Expect cooler temps with some fair wx cumulus clouds to develop,
especially over the higher terrain during peak heating. Temps
mainly in the 70s with northwest winds perhaps gusting to 15 to
20 mph and much lower humidity as dew points drop into the 40s.
Tomorrow night high pressure moves in with mainly clear skies
and cool temps with low temps in the 40s except lower 50s near
Lake Champlain and upper 30s at KSLK. Not sure we`ll reach
crossover temps so much widespread valley fog is questionable at
.SHORT TERM /THURSDAY/...
As of 338 AM EDT Tuesday...Fair weather continues
through the middle of the week as high pressure slowly crests over
the North Country. Expecting mostly clear skies and light winds
Wednesday night, and this combined with any lingering low-level
moisture from Tuesday`s rains may allow for patchy fog to develop
late Wednesday night into early Thursday, mainly in sheltered river
valleys. Lows will be in the lower to mid 50s in the larger valleys,
while the mountain areas will drop down into the 40s, with a few
upper 30s possible in the Adirondacks. Thursday will see lots of
sunshine once any fog burns off with highs in the mid 70s to lower
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
As of 338 AM EDT Tuesday...High pressure will continue to
dominate the region through Saturday, keeping the weather dry
into the weekend. Temperatures will remain warmer than normal
with highs in the mid to upper 80s and lows in the mid 50s to
mid 60s. The next chance of rain begins to threaten on Sunday as
an upper low pinwheels across the Great Lakes. This will place
New England under deep south flow, which will usher moisture
back into the region. This low will meander over the Great
Lakes/Ohio River Valley as it gradually becomes an open wave
through early next week, keeping the threat of showers and
thunderstorms around into Tuesday. Temperatures will remain near
or slightly above normal for late July.
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
Through 12Z Wednesday...Cold front pushing through KBTV over the
next hour or two with scattered showers and isolated thunder
with locally heavy rain and gusty winds. Local IFR Vis/MVFR
cigs with the front, otherwise mainly VFR. South winds are
shifting to the west then northwest behind the front through the
afternoon becoming more north to northwest overnight into
tomorrow with winds around 10 kts perhaps a few gusts of 15 to
20 during midday Wednesday. Thinking mainly dry air advection
on 10 to 20 knot winds around 500 feet agl will limit areal
coverage of fog/br overnight. Maybe a 1 to 2 hour window near
sunrise at slk of some ifr conditions on Weds morning. Could
also be some morning stratus at SLK but not confident enough to
include otherwise there may be some SCT050 cumulus forming over
the higher terrain but airmass is quite dry so not expecting
Wednesday Night: VFR. Patchy BR.
Thursday: VFR. NO SIG WX.
Thursday Night: VFR. NO SIG WX.
Friday: VFR. NO SIG WX.
Friday Night: VFR. NO SIG WX.
Saturday: VFR. NO SIG WX.
Saturday Night: VFR. Slight chance SHRA.
Sunday: VFR. Chance SHRA.