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Area forecast discussion 
National Weather Service Binghamton New York
948 am EDT sun Jul 24 2016

Synopsis...
hot and dry conditions will continue today as high pressure
dominates the weather. A storm system will move across the region
Monday bringing showers and thunderstorms. High pressure will
build back over the region on Tuesday.

&&

Near term /through tonight/...
930 am update...

Temperatures rising steadily through the 70s on their way to the
upper 80s and lower 90s again. Upped hourly and Max temps. Some
high clouds but hindering heat little. Should be a few degrees
warming than yesterday for most of the County Warning Area. Surface high pressure
will keep it dry today. Will be watching convection over Michigan
as it drops southeast into PA this afternoon and evening.

600 am EDT update...
today will be hot and dry as high pressure at the surface and
ridging aloft builds into the region. Some cirrus is spreading into
the region along the outer edge of the ridge aloft, but for the most
part around sunrise the area will start with mostly sunny skies.

Around 18z the flow aloft will transition into SW resulting
strong warm air advection over the region. This warm air advection will result in cloud coverage
increase from SW to NE and by 00z most of the area will have
partly cloudy to mostly cloudy skies. The cloud coverage however
will not suppress the Summer heat across the region. Temps are
expected to range in the upper 80s to low 90s again today. Less
moisture will be present over the region today, thus heat index
values will be near the ambient value.

Tonight the forecast starts to become messy and complicated. A
vorticity maxima embedded within the SW flow aloft will move across
the region which may bring showers and thunderstorms to the region.
Showers are expected to move across western PA as early as 03z
tonight and impact nepa around 6z and may last through 12z. Due to
warm air advection, temps will remain pretty high with temps only falling into the
upper 60s to low 70s. Relative humidity values will be high as well making Monday a
warm and muggy start.

&&

Short term /Monday through Tuesday night/...
400 am EDT update...
Monday morning the weather starts to become more interesting. A
shortwave trough is expected to move across the Great Lakes region
and lift northward into Quebec. This system is expected to produce
showers and thunderstorms over the region through the day. A wave
ahead of the main trough will move across the New York/PA Monday
morning,then a cold front is expected to move across New York/PA mid to
late afternoon. The first wave is expected to produce scattered
showers and thunderstorms across the region and last most of the
morning.

Additional showers and thunderstorms are expected to develop again
in the afternoon. This is the time frame where it could get
interesting. Sfc temps are expected to rise quickly across the
region which should create an unstable environment during the
afternoon. The typical guidance shows the NAM has higher sb cape's
than the GFS, but for the most part we should see at least 1000 j/kg
across the region, 1000-850mb mu cape values are around 2000 j/kg mid
afternoon, and bulk shear will range from 30 to 40 knots. The
combination of the parameters stated above, along the a frontal
boundary, will create an environment conducive for showers and
thunderstorms to develop. Some of these showers may become strong or
become severe.

Confidence overall for severe is on the lower side. Am concerned
with the mid-lvl lapse rates, all year they have just not been steep
enough to support the storm to transition to strong to severe, temps
aloft have been very warm. The dynamic wave attendant to the frontal
boundary appears to be weaker than previous model runs, and the
greatest forcing will be north of the County Warning Area. Another concern is will
the region truly rebound enough after early morning showers to
allow a second round of activity. With that being said, will keep a
close eye on how the system evolves. Storm Prediction Center currently has US within a
marginal risk and wind is the main threat with expected storms.

Heat index values will be in the upper 90s Monday afternoon as
moisture increases across the area. A few locations may hit 100,
for an hour, but not long enough for an advisory. Caution should
still be taken to prevent heat related illness. High pressure
will build in behind this system and will result in Tuesday being
dry with seasonal temps.

&&

Long term /Wednesday through Saturday/...
high pressure will bring continuing seasonally warm temperatures
with mainly sunny skies and fairly comfortable humidity levels through
midweek. Forecast models begin to diverge as far as forecast
details for late in the week into next weekend however in the big
picture, upper level troughiness developing over eastern Canada
will support increasing chances for showers/storms over the area by
late week into next weekend. The end of the forecast period will
also tend toward slightly cooler daytime highs but warmer
overnight lows due to increasing clouds and low level dew points.

&&

Aviation /14z Sunday through Thursday/...
VFR conds will cont thru the pd. Northwest flow of warm air over the top
of the ridge remains. Tngt...shrt term models show a conv complex dvlpg
over the lwr lakes and diving sewrd into PA. This may bring some
late ngt tstms to avp...otrw it will be south of the otr taf
sites. Weak gradient will keep the winds lgt thru the pd.

Outlook...

Mon and Mon eve...showers and thunderstorms. Mostly VFR to MVFR.

Mon overnight to Thu...mainly VFR.

&&

Bgm watches/warnings/advisories...
PA...none.
New York...none.

&&

$$
Synopsis...kah/tac
near term...kah/tac
short term...kah
long term...pcf
aviation...dgm

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