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Area forecast discussion 
National Weather Service Albany New York
321 PM EDT Sat Jul 4 2015

Synopsis...
low pressure tracking to the south of the region will exit the
area this afternoon and early evening...bringing an ND to the rain
and showers. Improving conditions are expected tonight... with dry
and warmer weather to return for Sunday and Monday as high
pressure builds across the region.

&&

Near term /through tonight/...
as of 145 PM EDT...steadiest rainfall now south and east of
Albany. Back edge of the precipitation GOES from eastern Ulster County...to
western Albany County and then to central Saratoga and Washington
counties. Expect this back edge to steadily move eastward during
the rest of the afternoon...bringing an end to steady rainfall in
all areas by 4 or 5 PM. However...the trailing upper level trough
may still produce some showers in all parts of the forecast area.
Have forecast likely to catgorical probability of precipitation over the southeast to
lower to slight chance or low chance by later in the day. Over the
northwest...slight to chance are forecast for the afternoon.

Highs today will be in the middle 60s to lower 70s.

&&

Short term /Sunday through Monday/...
for the remainder of the Holiday weekend and into Monday...high
pressure will be building both at the surface and aloft through
the short term period per the NCEP model suite and ensemble
consensus. This will result in dry and increasingly warmer
temperatures /and humidity/ as h850 temperatures moderate into the middle
teens. This points toward high temperatures climbing well into the
70s and lower 80s on Sunday and well into the 80s /sub 90f/ on
Monday under a good deal of early July sunshine. Overnight lows
Sunday night into Monday morning will average mainly into the
55-60f general range.

&&

Long term /Monday night through Friday/...
some uncertainty remains regarding the exact timing of a frontal
passage during the middle of the upcoming week. The 00z GFS is a
little faster than the 00z European model (ecmwf)/ggem regarding the speed of a cold
front approaching the area. Because of this...the GFS suggest
showers/thunderstorms develop both on Tuesday along a pre-frontal
trough and again on Wednesday ahead/along the actual
boundary...while the ggem/European model (ecmwf) are mainly dry for Tuesday with
showers and thunderstorms for Wednesday. For now...will go with low
chance probability of precipitation for Tuesday into Tuesday night...and high chance probability of precipitation for
Wednesday. Temperatures look fairly warm in the middle 80s for both Tuesday/Wednesday
ahead of the boundary...with muggy lows in the middle to upper 60s for
valley areas for both Monday and Tuesday nights.

The frontal boundary may winding up stalling just south/east of the
region for Thursday into Friday...so will keep slight to low chance
probability of precipitation in the forecast for Thursday/Friday. If the front is more
progressive...it could wind up just dry everywhere...as high
pressure attempts to build into the area from the Great Lakes. Temperatures
will be a little cooler and less humid behind the front...with highs
in the low 80s for thurs/Fri...and overnight lows in the upper 50s
to low 60s.

Another shortwave could approach the region for some point next
weekend with another chance of showers/thunderstorms. Temperatures look to
be near normal levels.

&&

Aviation /18z Saturday through Thursday/...
as of 1745z...the shield of rain was beginning to move away from
the taf sites. However...residual low level will likely allow MVFR
ceilings/drizzle and fog(perhaps even brief IFR periods) to persist a
little while longer at all the taf sites.

We are seeing clearing well to the west of the taf sites. This
clearing will likely reach the tafs before end of the day.

The clearing at night...along with little or no wind and residual
wet ground...should yield to some fog overnight. One mitigating
factor fog formation will be the passage of a weak cold front
still slated to work across the region sometime this
evening through midnight...perhaps stirring the wind up a little.

For now...went IFR mist/ceilings at kpsf and kgfl from 08z-12z...and
only MVFR mist at kalb/kpou. We will monitor conditions through
the afternoon and evening hours.

After we loose the fog Sunday (after 12z)...it looks like a much
better day for flying as we return to full VFR conditions...with
few-scattered cumulus developing with light to northwest wind around 5kts.
Visibility will be unrestricted.

Outlook...

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

&&

Fire weather...
increasing wet weather probabilities through this morning into the
early-middle afternoon hours will keep relative humidity values rather elevated to
between 55-75 percent. Moist low levels and some patchy fog
tonight will keep relative humidity values at or above 90 percent. Then generally
dry weather will return for Sunday and Monday as high pressure
once again builds across the region.

&&

Hydrology...
increasing probabilities of a period with wet conditions this
morning into the early-middle afternoon hours with forecast quantitative precipitation forecast/S
ranging from one-tenth to one-third of an inch across the
region...isolated higher amounts are possible where convection
develops /mainly into the Adirondacks/. These rainfall amounts
will have little if any effect on flows on area streams and
rivers.

Dry conditions are expected for Sunday and Monday.

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...gjm/bgm
near term...hwjiv/gjm/bgm
short term...bgm
long term...frugis
aviation...hwjiv
fire weather...bgm
hydrology...bgm

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