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Area forecast discussion 
National Weather Service Albany New York
1017 PM EDT sun Jul 13 2014

Synopsis...
with warm humid air in place across the areas...a series of frontal
systems will move across the area through Tuesday with bouts of
showers and scattered thunderstorms...some of which may be strong
and produce heavy rainfall. Our weather will improve midweek as it
turns cooler and less humid.

&&

Near term /through tonight/...
as of 1000 PM EDT...severe thunderstorms threat across the southeast part of
the forecast has ended and Severe Thunderstorm Watch 415 has been
cancelled. Will keep likely probability of precipitation for a couple of hours longer over
eastern and southern areas until showers/thunderstorms clear out by shortly
after midnight. Otherwise probability of precipitation are forecast to decrease to slight
chance or dry levels for most of the region...and chance probability of precipitation south.

Previous discussion...
later tonight...the weak cold front will push into the fca from the
northwest...then drift slowly south overnight...stalling east-southeast-west-southwest from S new
eng into PA as it becomes parallel to the 500 hpa flow. Its impacts
will be largely a wind shift and a slight dcr in dew point. Overnight a
bubble surface high forms over New York state. -Shra activity will end from northwest to southeast
overnight..with model suite suggesting some drying. However most of this
is aloft...low level moisture will remain in light surface flow...with dew point in
middle to upper 60s...and areas of low clouds and fog will form
overnight.

&&

Short term /Monday through Wednesday/...
there will be a continued threat for showers and thunderstorms
through at least Tuesday evening.

As the deep cutoff upper level low slowly spins across the Midwest
and Great Lakes region...a surface cold front will slowly approach our
area from the west. With a continued moist southerly flow ahead of
this system...there will be showers and thunderstorms affecting our
region for the next 60 hours until the cold front can cross through
our area. It is still unclear exactly when this cold frontal passage
will occur...as the models are still not in total agreement...but it
looks to be sometime between late Tuesday and early Wednesday
morning.

Before then...repeated rounds of showers and thunderstorms can be
expected. With precipitable waters remaining high...there will be a continued
threat for heavy rainfall with any thunderstorm...and potentially
flash flooding. With expected cloud cover...instability will be
limited...so the severe potential is not very high. The best chance
for organized areas of heavy rain with thunderstorms will be Tuesday
and early Tuesday night...which is still too far out to consider any
flood watches.

Some showers may linger into Wednesday morning over the eastern
zones...otherwise Wednesday will see decreasing clouds and less
humid and cooler air moving in.

Highs Monday will be in the middle 70s to middle 80s. Lows Monday night in
the upper 50s and 60s. Highs Tuesday in the middle 70s to middle 80s once
again. Lows Tuesday night in the 50s north and west...upper 50s and
60s south and east. Highs Wednesday generally in the upper 60s and
70s.

&&

Long term /Wednesday night through Sunday/...
this will be a mainly dry stretch of weather...with sprawling high
pressure in place...and low pressure no closer than Cape Hatteras at
any time during the period. High temperatures will climb each
day...starting out with highs on Thursday from the upper 60s to
around 80 degrees...and finishing with highs on Sunday from the middle
70s to middle 80s. Lows Wednesday and Thursday nights will range from
the middle 40s to upper 50s...then Friday night will begin a milder
trend...with lows Saturday night from mainly the middle 50s to lower
60s.

&&

Aviation /18z Sunday through Friday/...
possible severe thunderstorms have weakened or exited the kpou
area...but the threat of thunderstorms with gusty winds and MVFR/IFR
conditions will remain there through around 03z since another line
of thunderstorms was moving across Delaware and Sullivan counties.

At kalb/kgfl/kpsf expect some rain showers to continue through
around 03z with occasional MVFR conditions.

After 03z expect just isolated to scattered showers at the taf sites...but
MVFR/IFR will slowly begin to develop. Due to cloud cover that will
linger through most of the night...dense fog development may not be
able to occur...so have generally forecast the fog in the MVFR
range.

After 12z on Monday...expect mainly VFR conditions at all the taf
sites...but thunderstorms will develop again during the afternoon...
especially at kpou/kpsf where prob30 groups have benn added between
18z Monday and 00z Tuesday. At kalb/kgfl have only added vcsh during
that time period.

Surface winds will generally become light south tonight at 5 kts or
less...but expect wind gusts of 15 to 20 kts at kalb/kpsf until
02z/03z before the wind diminishes. On Monday winds will be
southerly at 5 to 10 kts.

Outlook...

Monday night: moderate operational impact. Chance of rain showers...tsra.
Tuesday: moderate operational impact. Chance of rain showers...tsra.
Tuesday night: moderate operational impact. Chance of rain showers...tsra.
Wednesday: low operational impact. Slight chance of rain showers.
Wednesday night: no operational impact. No sig weather.
Thursday: low operational impact. No sig weather.
Thursday night: no operational impact. No sig weather.
Friday: no operational impact. No sig weather.

&&

Fire weather...
fire weather concerns will be limited over the next few days. A
slow moving frontal system will bring several opportunities for
showers and locally heavy thunderstorms between today and Tuesday.
Relative humidity values will generally remain above 60 percent through Monday
night.

&&

Hydrology...
a slow moving frontal system will bring repeated rounds of showers
and thunderstorms to the region through Tuesday night.

With precipitable water values near two inches...there will be a risk for locally
heavy rainfall within any thunderstorm. At the very least...rainfall
rates will be high enough to cause flooding of small streams...poor
drainage...low lying and urban areas. If repeated thunderstorms
track over the same location within a short period of time...flash
flooding will be possible...especially within any urban locations.

Once the cold front passes through the area sometime late Tuesday
night into Wednesday morning...the threat for heavy rain will end
and cooler and less humid air will work into our region for the
remainder of the week. This will allow for any high water to
recede.

For details on specific area rivers and lakes...including observed
and forecast river stages and lake elevations...please visit the
advanced hydrologic prediction service /ahps/ graphs on our
website.

&&

Aly watches/warnings/advisories...
CT...none.
New York...none.
Massachusetts...none.
Vermont...none.

&&

$$
Synopsis...Snyder
near term...gjm/Snyder
short term...gjm
long term...elh
aviation...gjm
fire weather...frugis
hydrology...frugis/Snyder

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