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Area forecast discussion 
National Weather Service Albany New York
144 PM EDT Thursday Sep 29 2016

despite some clouds, mainly dry weather is expected through the
day today with seasonable temperatures. A slow moving low pressure
system near the Ohio Valley will gradually move towards New York
and New England for Friday into the weekend, allowing for an increased
threat for rain showers with cooler temperatures. The storm system
may linger into early next week with a continued chance for rain


Near term /until 6 PM this evening/...
overall forecast is in good shape. Clouds keep trying to spread
northward however northeast-east flow advecting drier air which
keeps eroding the clouds. Only some minor adjustments were made.

High pressure centered in Canada is winning the battle against
the moisture on the outer periphery of the upper low in the Ohio
Valley. The line between clearing and a sunny sky is in the
Schoharie valley through the eastern Catskills, Mid Hudson valley
and northwest CT. Based on trends in satellite imagery, this line will be
nearly stationary into early this afternoon, then may begin to
trend northward through the rest of the afternoon. A few fair
weather clouds should form throughout the day in the sunny areas.

Rain is west of our region and should mainly stay west of our
region through the daylight hours, then build north and east
through the night. So, have adjusted sky cover and rain chances
through the day and into this evening. Have raised temperatures a
couple of degrees for this afternoon in areas seeing the sun. The
previous afd has a few more details and is below...

Some subsidence from the nearby high pressure northeast of the
area and drier air moving in with the low-level northeast flow. As
a result, temps today look warmest across northern areas with
upper 60s to around 70 in those areas. Meanwhile, southern areas
look to stay the coolest thanks to the more clouds/possible
precip, with upper 50s to mid 60s further south and west.


Short term /6 PM this evening through Saturday night/...
there will be an increased threat for rain showers through the
short-term period, as the upper level low slowly starts to make
some eastern progress.

Most of tonight will continue to be dry, as the upper level low
continues to spin over the Ohio Valley. However, it should
continue to be fairly cloudy with lows in the 40s to low 50s.
Some far northern areas may drop into the upper 30s if a few
breaks in the cloud cover can occur.

Although the main upper level dynamics continues to be situated
well west of the area on Friday, the mid-level flow starts to
switch to the S-se, which should continue to advect more moisture
into the area off the western Atlantic. Some showers are possible
as early as Friday afternoon, mainly for far southern areas. Temps
on Friday will range from the upper 50s to upper 60s, with the
warmest temps across northern areas.

The best chance for showers looks to be Friday night into
Saturday/Sat night, as the upper level low starts to shift
towards the eastern Ohio Valley and weak impulses rotating around
it help promote the formation of showers. Precipitable water values look to rise
to around 1.50" for southern areas on Saturday, so there could be
some locally heavier burst of rain at times. The exact timing and
amounts of rainfall is tricky as this time due to uncertainty
regarding the track/timing of the upper level low, but best chance
for showers looks to be across southern areas. Min temps will
generally be in the mid 40s to mid 50s and highs will be in mid
50s to low 60s.


Long term /Sunday through Wednesday/...
the extended forecast begins unsettled with the pesky cutoff low
still impacting the forecast area into early next week.
However...high pressure will build in Tuesday into the mid-week with
fair and dry weather returning.

Sunday to Monday...good agreement with the medium range guidance
that the cutoff low lifts back north to northeast into the Great
Lakes region by the 2nd half of the weekend. An occluded front will
extend south to southeast of the sfc reflection of the cutoff over
portions of PA and New York. A short-wave rotating around the cutoff
will focus some scattered showers with a decent fetch of moisture.
Precipitable waters will be 1 to 2 Standard deviations above normal according to
the latest gefs. Pops were kept in the high chance category. Highs
on Sunday will be near early Oct normals with mid to upper 60s
across most of the fcst area with some upper 50s to lower 60s over
the higher terrain. Lows Sunday night will generally be in the
upper 40s to mid 50s. The upper low opens up and the cold pool
drifts over New York and New England. Diurnally-timed scattered showers
will be possible again. Temps will be similar to Sunday.

Monday night into Tuesday...the showers should diminish early in the
evening with the loss of the diurnal heating. The upper trough axis
finally moves downstream with some ridging building in from the
Great Lakes region...and the MS River Valley. A weak short-wave in
the north to northwest flow aloft may trigger isolated showers on
Tuesday, but it should be mainly dry with the ridge building in.
Lows Monday night will continue to be in the mid 40s to mid
50s...and highs will be similar to the previous days with mid to
upper 60s in the valley areas...and upper 50s to lower 60s over the

Tuesday night into Wednesday...fair and dry early autumn weather
continues with the sfc anticyclone building in over New York and New
England from southeast Quebec. Good radiational cooling conditions
will allow for lows in the 40s. Highs will continue to be near
normal for the first week of Oct.


Aviation /18z Thursday through Tuesday/...
high pressure controlling the weather with the upper low well to
the west in the Ohio Valley. The dominance of the high pressure has
resulted in just some scattered clouds well above 3000 feet and
in some areas skc, which will continue into this evening. Deeper
moisure is seen on satellite and radar drifting north and east out
of the mid Atlantic but the high pressure should hold rainand low
clouds off to our south until later tomorrow. Still, some high
clouds will thicken and gradually lower tonight through tomorrow
morning. By late morning or early afternoon, some shower activity
could just begin to affect the kpou, kalb and kpsf areas. Coverage
is in question but the best chances for steadier rain and some
potential MVFR conditions would be at kpou after 16z.

East to northeast winds around 10 kt with a few gusts near 20 kt
will diminish to just under 10 kt tonight and continue through
tomorrow morning.


Thursday through monday: moderate operational impact. Chance of
rain showers.


Fire weather...
plenty of clouds will be in place over the next few days as a slow
moving storm system impacts the region. Some showers will be
possible as well, mainly for tomorrow into the weekend. A wetting
rainfall will likely occur between Friday and Saturday across much
of the area.

Relative humidity values will only fall to 55 to 65 percent this afternoon. Relative humidity
values for Friday into the weekend will generally be above 60

East to northeast winds will be 10 to 15 mph today. Winds at
similar direction and speed are expected to continue tomorrow into
Saturday as well.


no flooding is expected over the next five days.

Dry weather has continued so far this month, but some needed
rainfall is finally in the forecast. A slow moving area of low
pressure will bring some rain showers to the region over the next
few days, with the bulk of the showers occurring between Friday
and Sunday. Amounts will vary from north to south and are still
rather uncertain due to the storm track, but total amounts look
to be at least a half inch. Southern parts of the region may see
over an inch of this much needed rainfall by early next week.
While it won't end the drought conditions in place, it will
certainly help.

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


Aly watches/warnings/advisories...
New York...none.


near term...iaa/frugis/NAS
short term...frugis
long term...wasula
fire weather...frugis

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