Area Forecast Discussion
Issued by NWS Burlington, VT
FXUS61 KBTV 252314
Area Forecast Discussion
National Weather Service Burlington VT
714 PM EDT Thu Aug 25 2016
Deep moisture along with a weak wave of low pressure aloft will
produce variable clouds along with the chance of a passing shower,
mainly south tonight into Friday morning. Behind this system a
return to dry, late summer warmth is expected for Friday afternoon
into Saturday of the upcoming weekend. The next chance of showers
will occur by Sunday afternoon into Sunday night with another weak
front, followed by more warm and dry weather for early next week.
.NEAR TERM /THROUGH FRIDAY/...
As of 300 PM EDT Thursday...A rather uneventful, late summer
night is expected across the area as variable clouds associated
with a weak mid-level trough skirt across the area. Fairly deep
subtropical moisture (PWATS to 1.75 inches) will remain in place,
though without large-scale synoptic forcing or a front to produce
low level convergence the coverage of showers looks scant at best,
focused most across our southern zones overnight per latest model
output and WV trends. Accordingly I`ve lowered pops into the
slight to low chance range tonight with many areas remaining dry
or seeing only a light sprinkle here and there. That said it will
feel quite muggy as surface dewpoints will generally average in
the 65 to 72 range under light winds, which won`t provide ideal
sleeping conditions. Low temperatures similar to last night,
mainly mid 60s to lower 70s.
On Friday the weak mid-level trough will exit east with any morning
showers/sprinkles ending by noon under gradually clearing skies east
to west. Synoptic background flow remains southwesterly with neutral
height falls indicative of little airmass change. Averaged model 925
mb thermal progs from 18-21Z are in the 19-22C range supporting late
afternoon highs mainly from 80 to 86F with perhaps a few upper 80s
in the Champlain and Connecticut River Valleys. Despite the warmth
dewpoints will be gradually lowering in the upper 50s to lower 60s
by late afternoon so humidity levels will feel tolerable.
.SHORT TERM /FRIDAY NIGHT THROUGH SATURDAY NIGHT/...
As of 317 PM EDT Thursday...Fairly quiet as general ridging aloft and
at the surface will be in firm control. Zero/Zilch/Zippo PoPs the
entire period. Temperatures will continue to be above normal (both
day and night). Some differences for Saturday temperatures between
the GFS and NAM. NAM is a few degrees warmer because it is
slightly faster in moving the ridge to our east and allowing a
more west/southwest flow aloft to develop. Either way, the
differences are only a few degrees, so I split the difference.
Lots of upper 70s to lower 80s with some mid 80s in the southern
valleys. Hopefully everyone can take advantage of the weather and
.LONG TERM /SUNDAY THROUGH THURSDAY/...
As of 317 PM EDT Thursday...12z guidance suite is in fairly good agreement.
Really only 1 organized system for the period, and that will be
an upper trough that will slide across the region late
Sunday/early Monday. The flow pattern is progressive, so the
showers will pass across the region fairly quickly. Minimal
instability as well (especially since the timing looks to be
overnight), so only a low chance of any thunderstorm. Looking at
primarily rain showers.
Other than that, the region will be in a west/northwest flow around
a large ridge centered over the mid-west. With the trajectory of the
flow, temperatures will remain above normal (a solid 4-7F degrees).
Still some hints that a weak disturbance may zip down on that
northwest flow mid week and perhaps spark a shower or two. However,
12z GFS and ECMWF differ in timing and details, so have only token
(15-25%) chances of showers for mid-week. That means a much higher
chance of mostly sunny and dry conditions.
All-in-all, it`s fairly typical to have a stretch of this kind of
weather at this point late in the summer.
.AVIATION /23Z Thursday THROUGH Tuesday/...
Through 00Z Saturday...SCT/BKN VFR/MVFR cigs expected through 12Z
Friday, then trending VFR all terminals with clearing skies. Weak
mid-level energy will swing through the area into tonight but have
kept all TAF sites dry as probability for precip too low to
include. Increasing moisture in the low levels indicate fog
potential, however cloud cover overnight and surface wind
remaining around 5 kts should prevent fog formation. Followed
previous forecaster trend to MVFR KSLK/KMPV, otherwise VFR
overnight. Surface trough wind shift after 18z Friday with winds
becoming northwest all taf sites.
Outlook 00Z Saturday through Tuesday...
00Z Saturday through 00Z Monday...VFR/high pressure.
00Z Monday through 00Z Tuesday...VFR with scattered showers/MVFR
00Z Tuesday onward...VFR/high pressure.