FXUS61 KBTV 190519
Area Forecast Discussion
National Weather Service Burlington VT
119 AM EDT Tue Jun 19 2018
Showers...some with heavy downpours... will end from north to
south shortly after midnight tonight. Much cooler and drier air
will follow the frontal passage, leading to a pleasant sunny
day on Tuesday as high pressure builds into the area. Another
weak front will push through Wednesday night followed by
slightly cooler and drier air from Canada for the Thursday with
seasonably warm temperatures into the weekend along with a
chance of a shower or thunderstorm.
.NEAR TERM /THROUGH TONIGHT/...
As of 1031 PM EDT Monday...Cold front continues to push
southeast across our area...basically just north of a Saranac
Lake-Burlington-Saint Johnsbury line. Showers were fairly
widespread ahead of the front across northern New York and
northern Vermont and there is still a potential for heavy
rainfall with this activity through about midnight before front
pushes far enough south to end the bulk of the precipitation.
Have kept the mention of heavy rainfall through midnight. Rest
of forecast remains in good shape and no other changes needed at
Rounds of showers and thunderstorms, a few severe with gusts to
60 mph, a few with very heavy rain will continue into the
evening and slowly sag southward ending overnight. Canceled the
heat advisory in the north due to rain cooled air.
Morning soundings at WMW and BUF show fairly decent low to mid
level lapse rates about 6.5 C/km with CAPES forecast in the
1000-2000 J/kg range. 0-6km shear values also 30-40 knots so
some organized severe thunderstorms are possible. Observed
precipitable water values ranged from 1.60 at BUF to 1.80" at
WMW so locally heavy rains a good bet. Flash flood guidance
ranges from 2.1 to 2.5" in and hour and 2.5 to 3.2" in 3 hrs, so
with rather fast moving storms it will likely take some
training of two or three storms to reach those numbers but we`ll
be keeping a close eye on that.
For tonight through Tuesday night...the front moves through the
area by midnight, ushering in cooler and drier air.
Showers/thunderstorms will come to an end and skies will
gradually clear by mid-morning Tuesday. Lots of sunshine
expected by the afternoon, along with a bit of a northwest
breeze. Tuesday`s highs will be in the lower to mid 70s, after
lows tonight in the mid 50s to around 60.
.SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/...
As of 454 PM EDT Monday...Generally quiet weather is expected
during this period with mean surface high pressure in control of
regional weather conditions. After a mainly clear night and
seasonable temperatures overnight Tuesday (45 to 55 F) skies
trend partly cloudy over time by Wednesday afternoon as a weak
surface trough approaches from the north. This feature will
approach the intl. border/nrn tier of counties later in the day
with perhaps a stray sprinkle or shower as advertised in some of
this morning`s output. Dry lower levels and only a narrow mid-
level moisture axis along the wind shift should keep coverage
rather minimal and as such have only carried lower end pops
generally below 30 percent in these areas accordingly. Highs to
rebound quite nicely, topping out in the upper 70s to lower 80s
in most spots.
Any lingering spotty sprinkles/light showers across the
northern counties will end Wednesday evening as the surface
trough clears southward and skies trend mainly clear. Lows again
near seasonable norms in the mid 40s to mid 50s.
.LONG TERM /THURSDAY THROUGH MONDAY/...
As of 454 PM EDT Monday...Fair and seasonably mild to warm
weather is expected to round out the work week as surface high
pressure bridges atop the region. Thursday will be the cooler of
the two days as highs top out in the upper 60s to mid 70s under
light northerly winds. Then a nice rebound by Friday as the
high slides east, southerly return flow commences and air of
midwestern origin advects into our area - mid 70s to lower 80s.
The next chance of appreciable precipitation arrives by later
Saturday into Sunday of next weekend as a dampening upper
shortwave lifts northeast from the Great Lakes and Ohio Valley
states. This feature looks to have decent moisture and with
lower- end boundary layer instability showers along with a few
thunderstorms will be introduced into the forecast. Temperatures
on both weekend days to run on the warm side but not
excessively so - mainly upper 70s to lower 80s for highs and
corresponding lows in the 50s to lower 60s.
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
Through 06Z Wednesday...Frontal zone clears south and away from
all terminals in the 06-12Z time frame as scattered lingering
showers end and any brief MVFR/IFR cigs trend VFR. Winds
generally light northwesterly from 5 to 10 kts. After 12Z VFR
continues as skies trend mainly SKC after 18Z. Winds continue
north/northwesterly from 6-12 kts and occasionally gusty into
the 15-20 kt range by afternoon before abating to light and
variable after 00Z.
Wednesday: VFR. Slight chance SHRA.
Wednesday Night: VFR. Slight chance SHRA.
Thursday: VFR. NO SIG WX.
Thursday Night: VFR. NO SIG WX.
Friday: VFR. NO SIG WX.
Friday Night: VFR. Slight chance SHRA.
Saturday: VFR. Chance SHRA.