Area Forecast Discussion
Issued by NWS Burlington, VT-- Highlight Changed Discussion --
-- Discussion containing changed information from previous version are highlighted. --
FXUS61 KBTV 260539
Area Forecast Discussion
National Weather Service Burlington VT
139 AM EDT Fri Aug 26 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 /UNTIL 7 PM THIS EVENING/...
As of 1259 AM EDT Friday...Based on satellite imagery have
tweaked the sky grids to better reflect current situation of
generally clear skies in Vermont and more noticeable cloud cover
in New York. This sharper gradient of clouds should lead to more
fog development over Vermont given clear skies...light winds...and
high dew points indicating plenty of low level moisture. Going
forecast of just a chance of showers during the early morning
hours looks good as weak shortwave moves across the region...but
it appears more active convection will remain well south of the
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 /7 PM THIS EVENING 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 /06Z Friday THROUGH Tuesday/...
-- Changed Discussion --Through 06Z Saturday...Look for VFR/MVFR conditions through about
15z this morning as plenty of low level moisture exists ahead of
an approaching cold front. This low level moisture will help to
create areas of fog to help reduce visibilities. In addition...
scattered showers ahead of the cold front will be moving across
the area which will also contribute to the MVFR conditions. The
front exits the area to the east around 15z and winds go from
south-southwest to west-northwest at speeds generally around 10
knots. Its at this point that drier air moves in and VFR
conditions quickly develop over the entire area for the remainder
of the period.
Outlook 06Z Saturday through Tuesday...
06Z Saturday through 00Z Monday...VFR/high pressure.
00Z Monday through 00Z Tuesday...VFR with scattered showers/MVFR
00Z Tuesday onward...VFR/high pressure.
-- End Changed Discussion --