FXUS61 KBTV 031910
Area Forecast Discussion
National Weather Service Burlington VT
310 PM EDT Fri Jul 3 2020
Weak high pressure builds into our region tonight into Saturday,
which will provide the North Country with drier conditions, along
with slightly cooler temperatures. Patchy fog is likely again
tonight across the valleys of central and eastern Vermont tonight as
temperatures cool back into the upper 40s to lower 60s. Highs on
Saturday and Sunday will be in the upper 70s to mid 80s with a few
scattered showers possible on Sunday afternoon. Our latest forecast
suggest the heat and humidity return by the middle of next week,
with highs mid 80s to lower 90s and lows in the 60s to near 70.
.NEAR TERM /THROUGH SATURDAY NIGHT/...
As of 309 PM EDT Friday...Any lingering showers/storms acrs
central-southern VT will quickly dissipate by 00z with the loss
of sfc heating/instability. Weak 1013mb high pres builds into
our cwa overnight, which will provide us with clearing skies and
light winds. Thinking fog/br is likely in the deeper protected
valleys of central/eastern and southern VT, including the NEK
tonight btwn 04z-12z Sat. Lows range from the upper 40s SLK to
lower 60s urban areas in the CPV. Fog is less likely here in the
CPV with weak southerly flow developing around 04z.
On Saturday large area of subsidence/dry air aloft on water vapor
upstream over the northern Great Lakes into southern Canada will
advect into our cwa. This will result in mostly sunny skies with
temps warming into the upper 70s to mid 80s, supported by progged
925mb temps in the 20-22c range. Would not be a few urban spots in
the CPV approach 90f, given the llvl thermal progs. Next question is
the potential for shower/storm? Forcing is very weak and dry air
overhead, but an isolated shower or low top thunderstorm is
possible, especially southern/central Green Mtns in VT. Leftover bl
moisture will support sfc based cape values in the 500 to 700 j/kg
range, with weak convergence near the trrn providing some lift for a
couple of showers. Areal coverage will be minimal and very isolated.
For Saturday Night very quiet night anticipated with weak 1013mb
high pres overhead and dry air aloft. 925mb to 850mb flow is <10
knots, so with recent rainfall and potential for some areas to fall
below cross over values, expect fog in the deeper protected valleys
of central/eastern VT and parts of the dacks. Lows generally in the
upper 40s to lower 60s.
.SHORT TERM /SUNDAY THROUGH MONDAY/...
As of 309 PM EDT Friday...Mostly dry conditions likely for Sunday,
while an elongated upper vort max and attendant surface low
reinforces the marginally drier and cooler airmass overhead. A
few showers or storms will be possible during the afternoon.
High temperatures should reach the lower to mid 80s. Mid to high
level clouds remain overhead as an upper vort traverses the
area overnight, keeping lows in the upper 50s to lower 60s.
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
As of 309 PM EDT Friday...A prolonged period of muggy, hot weather
is in store for the North Country beginning mid-week next week.
Monday will be pick of the week, with mostly dry conditions and
sparse shower/thunderstorm activity during the afternoon. Highs
a couple degrees warmer than Sunday with mid 80s, locally into
the upper 80s. Then, an anomalous upper ridge will become
established over our region and a warmer air mass advects into
the region. What the previous heat wave lacked in higher
dewpoints, this upcoming heat wave will feature upper 60s to
lower 70s dewpoints. Thus, heat stress will be more likely.
While strong, this upper ridge does not appear so strong as to
cause significant capping overhead like the heat wave from a
couple years ago. Thus, afternoon showers and thunderstorms may
prevent us from achieving excessive warmth. Though if an
offshore low develops as the ECMWF/GDPS suggest, better moisture
will be tied to that feature, and we could be looking at drier
conditions for Friday. Have kept forecast highs in the lower 90s
following blended guidance as a result, but any drier day (like
next Friday) could make for the mid 90s. We will continue to
refine the forecast as more details become available.
.AVIATION /19Z FRIDAY THROUGH WEDNESDAY/...
Through 18Z Saturday...Cumulus clouds continue to develop acrs
central/southern VT mtns with a few light showers over eastern
sections. The best potential for a scattered shower/storm will
be at RUT/MPV btwn 18z-21z this aftn with brief mvfr cigs/vis
possible. Rest of our taf sites should remain VFR thru this
evening. Next question will be areal coverage of fog/br or low
stratus again tonight. Expect highest probability of ifr/vlifr
conditions in fog/br with vis blw 1sm will be MPV, followed by
RUT. Elsewhere, brief intervals of mvfr/ifr conditions possible
at SLK/MSS btwn 07-11z, but with southerly winds developing
around 04z at BTV, thinking VFR prevails. Any lingering ifr
should lift btwn 12-14z Sat, with vfr conditions expected at all
Independence Day: VFR. NO SIG WX.
Saturday Night: VFR. Patchy BR.
Sunday: VFR. Slight chance SHRA, Slight chance TSRA.
Sunday Night: VFR. Slight chance SHRA.
Monday: VFR. Slight chance SHRA.
Monday Night: VFR. NO SIG WX.
Tuesday: VFR. Slight chance SHRA.