Scientific Forecaster Discussion
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Area forecast discussion
National Weather Service Binghamton New York
926 PM EST Wed Nov 20 2019
a light northwest flow of air will keep clouds, and perhaps a
few sprinkles or flurries in the area overnight. High pressure
will build in briefly on Thursday bringing breaks in the clouds
and dry weather. A cold front will rush through on Thursday
night and Friday bringing showers, followed by a return to colder
Near term /through Thursday/...
with this latest update, the spatial extent of sprinkles/light
rain showers has been pulled back, with light precipitation
mainly downwind of The Finger lakes at this time. Temperatures
have been able to stay a couple degrees warmer than expected, so
limiting the potential for any freezing drizzle overnight to
mainly the higher elevations of central New York.
Previous discussion continues below.
Hi-res models continue to struggle to capture the sprinkles/light
rain showers across our area tonight. Sprinkles and rain
showers continue overnight mainly downwind of Ontario and The
Finger lakes with northwest flow, and across the higher elevations of
central New York. Soundings are still staying very dry through the
snow growth region overnight, so any precipitation will likely
stay as mainly a drizzle with some flurries possibly mixing in.
However, as temperatures drop back into the low/mid 30s and even
upper 20s across the higher elevations, some very light
freezing drizzle will be possible. Little to no ice
accumulations are expected, so we will hold off still on any
Short term /Thursday night through Saturday/...
weak warm front waves at the area late Thursday but the upper
support for precip is well back to the west. There is the off
chance of some light rain late in the day over the extreme
northern and western zones.
Thursday night the cold front crashes through the area late
bringing showers, mainly in the colder air behind the front.
Cold air is seasonable, with the 850 mb temps bottoming out
around -9c midday Friday. This should result in some continued
light lake effect showers, mixing with snow over the higher
elevations, especially later in the day. Surface temps above
freezing, but slowly dropping during the day will keep any snow
Surface pressure builds in Friday night and Saturday as warm
advection begins aloft. This will allow for a dry and warmer day
Saturday with a light west flow. Increasing high clouds are
likely late in the day from a low approaching from the south.
Long term /Saturday night through Wednesday/...
Model trends remain largely unchanged with regard to the two
systems for the long term - the first on Sunday and the other
heading into the midweek period. Therefore, no changes have been
made to the long term period.
Previous discussion continues below...
Medium range models continue to diverge in handling a high amplitude
trof, and associated low pressure development, moving into the
eastern third of the nation Saturday night and Sunday. Ensemble
spaghetti plots show a great deal of variance, but tonight's 00z
operational European model (ecmwf) and GFS models were agreeing on a more northerly
development of an East Coast low and a big jump in precipitation
chances for our area. Canadian nhemi model is still a miss as is the
mean of the gefs surface pressure and moisture fields. Confidence
remains low, but it's hard to ignore the latest model trends. My
experience tells ME to lean with westward/northward trending and
also tells ME to not jump into the deep end just yet. Nbm blended
guidance still appears to dry in this situation, so have nudged up
pops across the region on Saturday night and Sunday.
Beyond these early periods...quasi-zonal flow brings weak
disturbances and glancing effects of lake effect snow/rain showers
across our northern zones through Tuesday and generally fair
elsewhere. Next...ensemble clusters, including the operational
ec/GFS and Canadian models, point US toward Wednesday and
Thanksgiving day for our next potentially strong system to deal
with. Timing, strength and position of this system is all over the
place with a general tendency for a track again through the western
Great Lakes. That would suggest temperatures leaning on the warmer
side, or at worst marginal, for rain or snow showers depending on
time of day and change of airmass. To sum it all up...rather
unsettled for most days next week, but not unusually cold.
Aviation /03z Thursday through Monday/...
most of our terminals remain under MVFR to IFR ceilings tonight
with a broken cloud deck at around 1200 to 2500 ft. The
exceptions will be ith and bgm, where ceilings are coming in at
around 700 to 800ft tonight, dropping to alternate mins at times
with flurries and drizzle. Slight reductions in visibility are
also expected where this light precipitation can occur. Ceilings
across all terminals are expected to slowly improve after
sunrise, with mainly VFR by the afternoon as flow shifts to the
Winds mainly from the northwest at around 3 to 5 kts overnight
will turn light and variable after sunrise Thursday, then shift
to the south/southwest at around 3 to 5 kts Thursday afternoon.
Thursday night through Friday...restrictions likely in lower
clouds and rain showers as low pressure system passes.
Friday night...snow showers/flurries could bring restrictions,
mainly the New York terminals. Kavp perhaps an MVFR ceiling.
Saturday night through Sunday...system with snow-rain mix may
pass through the region with associated restrictions.