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FXUS61 KBGM 241901
AFDBGM

Area Forecast Discussion
National Weather Service Binghamton NY
301 PM EDT Sat Sep 24 2016

.SYNOPSIS...
Building Canadian high pressure will produce cool Fall-like
conditions through the weekend. Frost is possible early Sunday
morning and perhaps again for some spots Monday morning. After
slightly milder weather Monday, our next system will bring a round
of showers through the region late Monday into early Tuesday.

&&

.NEAR TERM /THROUGH SUNDAY/...
245 PM Update...

1028 MB high pressure over southern Ontario will control our
weather tonight, providing us with a real taste of fall. With 850
MB temps in the lower single digits, calm conditions, and a mostly
clear sky overnight, lows will feel quite chilly. We have
maintained the Frost Advisory areas east of I-81 where widespread
frost is likely with lows in the middle 30s. Elsewhere patchy
frost is possible in the deeper valleys of the central and western
Southern Tier, but expected to be more patchy due to the
likelihood of dense river valley fog. More urban areas such as
Syracuse and Scranton/Wilkes-Barre will likely hold in the 40s.

High pressure will slide overhead Sunday so after any early valley
fog, sunshine should be plentiful. With the 500 MB ridge axis to
our west through days end, a northwest flow will still keep us
quite cool with highs in the upper 50s to lower 60s. Not only will
it be a good 8 degrees below average highs for late September,
our recent warm September will make it feel even cooler.

&&

.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
Main concerns in the short term remain focused around the potential
for areas of frost Monday morning...the slightly warmer temperatures
Monday and the incoming cold front Monday night and Tuesday morning,
with showers and a few storms possible.

Sunday night will remain dry with high pressure at the surface
shifting slowly to the east and a high amplitude upper level ridge
over head. Should be another cool morning Monday under the ridge
with light/calm winds and potentially mostly clear skies. The fly in
the ointment may end up being a weak wave embedded in the ridge that
will move across the region and be potent enough to generate and
sustain an area of mid/high clouds. This would act to keep
temperatures a bit warmer through the morning hours. It appears the
coolest temperatures will end up being across the Catskills and
Poconos closer to the high. While areas to the west may miss out on
the favorable conditions for frost as high clouds move in ahead of
the next incoming cold front tracking through the Great Lakes.

So...will likely need another Frost Advisory for portions of the
forecast area Monday morning.

Most of the day Monday will be quiet with clouds increasing and
south winds strengthening ahead of the front. Will see the chance of
rain begin in the late afternoon across wrn NY...spreading through
the entire region as rain showers Monday night and Tue morning.
Rainfall amounts will generally be less than a half inch...with
most locations around a quarter of an inch.

Conditions dry out quickly behind the batch of rain late Tuesday as
the deep layer moisture really drops off and the much drier air
moves in.

&&

.LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/...
Conditions through the rest of the week will remain cool and
unsettled with a persistent northwesterly flow in place across much
of the region. A large area of low pressure aloft will be situated
near the Great Lakes and rotate slowly to the east through the week
ushering in a continuous supply of cool Canadian air. As this air
mass moves over the very warm waters of Lake Ontario...expect the
usual fall-type conditions with temperatures slightly below
average...plenty of clouds low chances of on and off rain showers.
Will likely not see much in way of daily temperature fluctuations
with the cloud cover keep temps cool during the day and relatively
warm at night. Highs will generally top out in the 60s...with
overnight lows in the upper 40s and 50s.

Will start to see an end to this pattern toward Friday as the upper
low moves to the east and high pressure begins to build in from the
west. Temperatures will inch upwards a few degrees going into the
weekend.

&&

.AVIATION /19Z SATURDAY THROUGH THURSDAY/...
VFR through the end of the TAF period all terminals except KELM.
AT KELM valley fog likely after 06Z with airport mins being
approached between 09Z and 12Z. While fog is likely with at least
IFR restrictions, a bit of uncertainty remains with just how low
we will go. With that in mind I kept our TEMPO group at KELM just
above airport mins but future updates may need to lower this. An
improvement to VFR expected after 13Z at KELM.

OUTLOOK...

Monday...VFR except possible early morning valley fog ELM which
could be IFR or worse.

Late Monday-Early Tuesday...A period of restrictions likely as a
frontal system moves through with showers.

Tuesday afternoon-Thur...Generally VFR but brief restrictions
possible in scattered showers.

&&

.BGM WATCHES/WARNINGS/ADVISORIES...
PA...None.
NY...Frost Advisory from 2 AM to 8 AM EDT Sunday for NYZ009-036-037-
     045-046-057-062.

&&

$$
SYNOPSIS...Heden
NEAR TERM...Heden
SHORT TERM...BJT
LONG TERM...BJT
AVIATION...Heden