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000
FXUS61 KBTV 261430
AFDBTV

Area Forecast Discussion
National Weather Service Burlington VT
1030 AM EDT Wed Jul 26 2017

.SYNOPSIS...
High pressure will crest across the area today with sunny to
partly sunny skies through a good part of the day along with
seasonably mild temperatures. A weak cold front will approach
from the northwest tonight, passing through the area during
Thursday. Scattered to numerous showers along with a few
thunderstorms will be possible during this period. Behind the
front, fair and seasonably warm weather is expected by Friday
into the upcoming weekend.

&&

.NEAR TERM /THROUGH THURSDAY/...
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As of 1015 AM EDT Wednesday...Almost all fog has lifted across
the area, however still some fog holding on along the
Connecticut river valley around St. Johnsbury. This should lift
as we continue heating of the day. Light adjustments were made
to cloud cover across northern NY to show deck of stratus per
current satellite. Otherwise, high pressure centered near
Rutland will keep skies clear for most of day. Early morning
temps were updated as well with current obs to show temp trends
across the area. For this evening, HRRR/NAM solutions show
precip moving in slightly quicker than expected to St.
Lawrence valley so updated PoPs reflect this thinking, however
slot of dry air between 800-400mb may make it difficult for
precip to reach the ground.

Prior discussion...
Other than patchy morning dense fog, a great day remains in
store for the forecast area as expansive high pressure bridges
atop the northeast. Sunny to partly sunny skies are expected for
the majority of the day with light southerly winds, modest
humidity and temperatures in the 70s to around 80. An
approaching surface trough to our northwest across southern
Ontario will begin to push some mid level cloud cover into
northern counties by late afternoon or early evening but any
precipitation associated with this feature should hold off until
after sunset.

By tonight, the first wave of showers arrives from the west and
northwest over time as mid level heights fall and weak embedded
shortwave energy skirts through the mean flow aloft. Have maintained
solid chance to likely pops (40-60%) after midnight in most areas,
though rainfall should be on the lighter side and generally less
than a third of an inch. Did opt to include low probabilities for a
few storms across northern New York later tonight where evidence of
weak mid level instability is offered in various global and
mesoscale solutions. Nothing strong to severe though. Lows hold on
the mild side under light to modest southerly flow - mainly upper
50s to mid 60s.

By Thursday the primary surface trough swings through the area by
the afternoon hours as winds trend westerly over time. Good moisture
convergence in vicinity of the boundary warrants maintaining solid
chance pops for scattered showers and a few thunderstorms. Modest
instability combined with decent 0-6 km shear into the 30-35 kt
range will interact with a favorable afternoon timing to perhaps
allow for a few stronger to locally severe storms, mainly from the
Champlain Valley eastward where SREF/NAM calibrated severe progs are
highest. Confidence only modest at this point as clouds may limit
boundary layer destabilization processes. Per coordination with
GYX/ALY offices and current SPC Marginal Risk for our region will
introduce low probabilities for gusty winds and small hail into
the forecast in these areas accordingly, mainly in the noon to
6 pm time frame. Highs will be similar to today - mainly 70s to
perhaps a few spot readings near 80 though with dewpoints
climbing into the 60s humidity levels will be higher.
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&&

.SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY/...
As of 345 AM EDT Wednesday...Front moves away from the area
Thursday night and some showers will linger during the first
half of the night before ending, Friday will also be dry. Cold
air advection continues through the day, temps should top out
in the lower to mid 70s, about 5 degrees below our seasonal
normal of 81 for this day. During the day Friday an closed upper
level low will track from lower Michigan towards Western
Pennsylvania. At this time looks like showers associated with
this feature will remain well south of our area.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
As of 345 AM EDT Wednesday...Our region will have dry weather
extending from Friday through Monday. Surface and upper level
ridges maintain the drier air mass over the area. Aforementioned
upper level low will pass from Western Pennsylvania on Friday
night eastward and off the New England coast by Saturday night.
Precipitation should remain south of our forecast area. Surface
high begins to slide eastward on Monday and chance for showers
by afternoon and evening with a front approaching our area from
Canada. Right now it looks like front won`t actually cross our
area till later Tuesday afternoon towards the end of the
extended period.

&&

.AVIATION /14Z WEDNESDAY THROUGH SUNDAY/...
Through 12Z Thursday...MVFR/IFR/LIFR in mist and fog through
the 13-14Z time frame at KSLK and KMPV. Otherwise VFR through
the forecast period with SKC to SCT cigs in the 050-100 AGL
range through 00Z. Exception in the SLV and at KMSS terminal
where more prevalent OVC skies will prevail this morning,
generally from 040-060 AGL. Winds trending light southerly from
5 to 10 kts through the day. After 00Z skies trend OVC with
increasing chances for showers into the overnight hours with
approach of upper trough. An outside shot of a stray
thunderstorm at KMSS late in the forecast period. Conditions
generally remain VFR though brief reductions in visibility to
MVFR possible in steadier showers. Winds calm to light
southerly.

Outlook...

Thursday: VFR. Likely SHRA. Chance TSRA. A few stronger storms
possible with brief MVFR/IFR.
Thursday Night: VFR. Chance SHRA.
Friday: VFR. Slight Chance SHRA.
Friday Night through Sunday: VFR. NO SIG WX.

&&

.BTV WATCHES/WARNINGS/ADVISORIES...
VT...None.
NY...None.

&&

$$
SYNOPSIS...JMG
NEAR TERM...JMG/LaRocca
SHORT TERM...Neiles
LONG TERM...Neiles
AVIATION...JMG