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fxus61 kaly 222011 
afdaly

Area forecast discussion
National Weather Service Albany New York
411 PM EDT Fri Sep 22 2017

Synopsis...
high pressure at the surface and aloft will remain parked over
the region through the next several days, providing dry
conditions and continued above normal temperatures. Tropical
Storm Jose will remain nearly stationary south of Cape Cod, and
will gradually weaken over the next few days with no impacts for
eastern New York and western New England. Temperatures could
reach record high levels Sunday into Monday, as the ridge
strengthens overhead.

&&

Near term /until 6 am Saturday morning/...
high pressure just north and west of our region with the
tropical system offshore. North to northeast low level flow
should slowly ease through the night as drier low level air
advects from north to south.

Light winds and a clear sky will help temperatures to fall and
fog should form along rivers, lakes and swamps but not spread
much beyond that. Areas of western New England may see more
intervals of high clouds on the northern periphery of the
tropical system along with intervals of light north to northeast
winds.

Lows tonight in the 50s, but 40s northern areas and maybe upper
50s to near 60 Mid Hudson valley, northwest CT and southern Berkshires,
where again, there could be some intervals of high clouds and
some light persistent north to northeast low level flow.

&&

Short term /6 am Saturday morning through Monday/...
upper ridging builds into the region through Monday with the low
level thermal ridge building south into our region from the
north and northwest. Low level ridging is expected to build
overhead from the west and north as well, causing low level
flow to weaken to light and variable, limiting mixing potential.

Boundary layer temperatures warm to levels that would result in
surface temperatures solidly in the 90s if it were the middle of
Summer but the rapidly decreasing sun angle and the lack of wind
to help with mixing could limit the warming potential. Low level
moisture should increase but with low level flow so weak,
surface dew points may not get as high as guidance suggests.
Temperatures at night may be able to fall to the lower end of
guidance Saturday night and Sunday night as the lack of rain
recently has contributed to relatively dry ground and nights are
getting longer now that we are into autumn.

So, it is tough to say how much mixing we will get as
temperatures upstream in the Midwest are getting into the 90s
but in recent days, we just have not been mixing as well as we
have in the Summer even with full sun and at least some wind
during the day.

Still forecasting solid 80s Saturday with some 70s higher
terrain. Even if we do not reach full mixing potential Sunday
and Monday, we should see record high temperatures. The question
is whether we hit 90 in some areas either day or both days.
Full mixing potential if we were in the middle of Summer would
suggest possible highs in the mid 90s but again it is autumn,
with light winds and a much lower sun angle. It may hit 90 but
it will feel quite warm whether we are in the upper 80s or
around 90, with dewpoints at least around 60 if not lower 60s.

&&

Long term /Monday night through Friday/...
warm and dry conditions initially will transition to more seasonable
temperatures by late next week, with a possibility of some showers
during the transition.

Guidance is in agreement that the strong mid/upper tropospheric
ridging over the region will gradually weaken as a trough approaches
from the Great Lakes region by mid to late week. Hurricane Maria is
expected to remain off the East Coast, gradually moving
north/northeast. Please refer to the National Hurricane Center for
official forecasts on Maria.

Tuesday is expected to remain quite warm and humid, with high
temperatures potentially 20 or more degrees above normal in some
areas. Expect highs in valley areas well into the 80s, and could
approach 90, especially across portions of the upper Hudson River
valley and Mohawk Valley, which may remain slightly farther removed
from any possible marine-modified influence. Isolated showers could
develop across portions of the Mid Hudson valley and western New
England, perhaps due to some enhanced low level convergence from the
extreme outer edge of Maria's circulation. Tuesday night should be
warm and humid with lows mainly in the 60s.

A cold front should move across the region sometime between
Wednesday and Thursday. Forcing looks fairly weak, with the main
upper level trough lagging quite far to the west. Will include
chance pops at this time. Highs Wednesday may still reach the lower
80s in valleys, with mainly 70s across higher terrain. Wed nt/Thu am
lows should fall into the mid 50s to lower 60s.

In the wake of the front, progressively cooler air should move into
the region for later Thursday into Friday, with temperatures
gradually falling back to more seasonable levels. With the main
upper level trough remaining west of the region, some showers may
also persist, especially across northern mountain areas where a
combination of orographic and lake enhanced effects may occur.
Thursday highs should be in the 70s in valleys, and 60s across
higher terrain, with overnight lows Thu nt/Fri am falling into the
mid 40s to lower 50s. Highs Friday only in the 60s for valleys, and
50s across most higher elevations.

&&

Aviation /20z Friday through Wednesday/...
high level cirrus clouds rotating around the extreme northwest
periphery of Post-tropical storm Joe moving across the area,
with some stratocu with 3-4 kft based occasionally drifting
across kpsf. Dry air mass in place will lead to mainly VFR
conditions through the 24 hour taf period ending 18z Saturday.
Some light fog may develop at kgfl with possible MVFR vsby, but
dry air in low levels should preclude any thicker/persistent
fog.

Winds through early evening will be northerly around 7-12 kt
with gusts near 20 kt especially at kpou. Winds will become
variable at 5 kt or less later this evening through the rest of
tonight.

Outlook...

Saturday night through Tuesday night: no operational impact. No
sig weather.
Wednesday: moderate operational impact. Scattered rain showers.

&&

Fire weather...
high pressure at the surface and aloft will remain parked over
the region through the next several days, providing dry
conditions and continued above normal temperatures. Tropical
Storm Jose will remain nearly stationary south of Cape Cod, and
will gradually weaken over the next few days with no impacts for
eastern New York and western New England. Temperatures could
reach record high levels Sunday into Monday, as the ridge
strengthens overhead.

Relative humidity values will be in the 75 to 100 percent range tonight and
Saturday night. Relative humidity values will drop to 45 to 60 percent Saturday
afternoon and Sunday afternoon.

North to northeast winds at 15 mph or less will become light
and variable Saturday through Sunday.

&&

Hydrology...
no widespread hydrologic issues are expected through the next
week. An extended stretch of fair and warm weather is forecast
well into next week as high pressure dominates.

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.

&&

Climate...
record high temperatures will be possible Sunday and Monday.

Here is a list of the current record highs for September 24/25:

Albany ny:
September 24th/sunday: 87 degrees 1961
September 25th/monday: 89 degrees 1970
daily records date back to 1874

Glens Falls ny:
September 24th/sunday: 86 degrees 1961
September 25th/monday: 84 degrees 2007
records date back to 1949

Poughkeepsie ny:
September 24th/sunday: 91 degrees 1959
September 25th/monday: 89 degrees 1970
records date back to 1949, however data is missing
from January 1993 through July 2000.

&&

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

&&

$$
Synopsis...NAS
near term...NAS
short term...NAS

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