Scientific Forecaster Discussion
fxus61 kbgm 162328
Area forecast discussion
National Weather Service Binghamton New York
728 PM EDT Mon Sep 16 2019
exiting cold front to the south and drier air moving in from the
north will allow cloud cover and lingering rain showers to come
to an end. High pressure will build into the region for the
remainder of the week with warming temperatures and quiet
Near term /through Tuesday night/...
630 PM update...
little change with this update apart from ingesting latest
observations and guidance. Skies are clearing across NE PA and
the southern tier a little more quickly than expected, while
additional mid-level scattered to broken clouds are moving in
across The Finger lakes and Mohawk Valley areas. Sky grids have
been adjusted accordingly. Increasingly clearer skies are
expected into the night, with patchy fog possibly starting to
develop a couple hours earlier than previously expected given
latest sky trends.
Previous discussion continues below.
3 PM update... main concerns in the near term are
focused on the extent of the cloud cover this evening and
tonight...along with the cool overnight temperatures and
potential for valley fog tonight and again Tuesday night.
A very dry period will set up across New York and PA tonight through
Tuesday night with a well amplified ridge of high pressure aloft
building into the Great Lakes, and an associated surface high
filling into the ern Great Lakes and northeast.
Cloud cover and a few lingering light rain showers associated
with a weak sfc cold front will be found across the central srn
tier of New York and most of NE PA into the early evening hours
today. The front will continue to sag to the south as the drier
air moves in from the north. This pattern will allow for
generally clear skies tonight and when combined with light or
calm winds, will lead to potentially significant radiational
cooling. Temperatures are expected to drop into the 40s across
much of the region...with lower 40s into the higher terrain of
the Catskills and Tug Hill, and mid to upper 40s all other
locations. This set up will also lead to another night of
fog...mainly in the valley locations.
Tomorrow will be quiet with mostly sunny skies after the fog
lifts and mixes out. Highs in the afternoon will top out a few
degrees warmer than today...into the upper 60s and lower 70s.
Tuesday night will see enough clearing for lows in the 40s again
and patchy valley fog as well.
Short term /Wednesday through Thursday/...
3 PM update...
no major changes made to the short term with very quiet weather
conditions expected under a building area of high pressure.
3 am update...
very quiet conditions are anticipated in the short term period.
Highs will edge up slightly as ridging aloft takes over, from
upper 60s-lower 70s Wednesday to mostly 70s Thursday except
highest elevations still in 60s. Strong radiational cooling of
dry air each night will yield lows of primarily 40s. A few our
typically coldest spots Tuesday night could even slip into
upper 30s, such as pockets of Delaware and northern Oneida
counties. This will also be ideal for typical late season valley
fog development each night-early morning.
Long term /Thursday night through Monday/...
3 am update...
there is high confidence for remarkably dry and quiet
conditions to persist, and temperatures will trend warmer.
High pressure at the surface, with amplified warm ridging
aloft, will remain in place right into the weekend. Main trend
of note, is for temperatures to get warmer each day. Highs of
mainly mid to upper 70s Friday, will reach upper 70s-lower 80s
for Saturday-Sunday. Dewpoints are anticipated to still be
comfortably low - mainly 50s - late this week. However, high
pressure will start to shift east Sunday which by then may allow
dewpoints to creep up into the 60s via southwest return flow.
Ridging aloft will also start to skew eastward, exposing US more
to southwest flow and increasing sky cover Sunday. Our next
actual rain chances still appear to wait until just after the
weekend in the latest operational models.
Aviation /00z Tuesday through Saturday/...
high pressure is building into the region with mostly VFR
conditions through the period everywhere except kelm. With the
clear skies and light winds overnight, dense valley fog will
likely form and with vlifr restrictions expected at kelm. Still
low confidence for kavp whether or not the fog will deep enough
to cause any restrictions, so have left it out of the forecast
for now and will reassess with the 06z forecast. After the fog
dissipates tomorrow morning, it will be mostly clear skies at
all sites and VFR conditions with light winds.
Tuesday through Saturday...VFR except late night/early morning
valley fog probable for at least kelm; possibly others.