Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Binghamton New York
640 PM EST Wednesday Jan 28 2015
cold and quiet through tonight...with crisp Arctic air. A south
wind will temporarily bring milder temperatures Thursday.
However...a low pressure system will spread accumulating snow
across our region late Thursday into Friday. Temperatures will
plummet Friday...with gusty winds sending wind chills well below
zero by Friday night.
Near term /through Thursday/...
high pressure will crest over the area this evening. With winds
diminishing and clear skies this will allow a quick drop in
temperatures due to radiational cooling. Middle and high clouds will
begin to increase overnight west to east ahead of the next system
but as this will occur after 06z still expecting lows generally in
the low to middle single digits.
Clouds will thicken up through Thursday morning with light snow
developing west to east across the County Warning Area during the middle afternoon
through the early evening time frame. Worth noting, there will
initially be a lot of dry air in the lower levels so the onset has
been delayed slightly from previous forecast package. Increasing
southerly winds will allow temperatures Thursday to reach the upper 20s
to around 30.
Short term /Thursday night through Saturday/...
the bulk of the accumulating snow with this next system looks to
fall through the evening into the overnight Thursday night.
Overall, forecast models are in fairly good agreement with this
system so generally followed a model blend but put a little more
weight on the NAM due to its handling of terrain effects.
Temperatures will initially hold fairly steady Thursday night due
to the southerly flow associated with the low as it moves east
over Lake Ontario. However as the low passes off to the east in
the predawn hours of Friday this will drag an Arctic front through
the region. Also expect steadier stratiform precipitation ahead of the
low to move off to the east around this time. However as strong
500 mb shortwave digs south across the region during the day
Friday associated with strong northwest winds at the surface off Lake Ontario this
will set up for an interesting day with a good set up for multi-
band snow showers and some squalls to affect central New York. This will
be accompanied by northwest wind gusts of 25 to 35 miles per hour. Temperatures will be
falling through the day due to the cold air advection with morning
highs in the 20s but temperatures falling through the teens during the
afternoon. In terms of snowfall accumulations, total amounts from
the initial system late Thursday into Thursday night plus the snow
showers Friday generally look to be in the 1 to 3 inch range from
around Binghamton southward into NE PA with most areas to the
north seeing around 4 inches or so...the exception will be the
northern zones where upwards of 6 inches will be possible due in
part to heavier lake effect Friday.
Snow showers will wind down through Friday night however expecting
a very cold night accompanied by continuing brisk winds. This will
result in wind chills in the minus teens to around minus 20 for
Saturday will feature a mix of sun and clouds as a narrow surface
ridge moves in. However temperatures will be well below average with
highs ranging from the single digits over Oneida County to the low
to middle teens elsewhere. With brisk winds continuing this will
result in daytime wind chills remaining below 10 above through the
Long term /Saturday night through Wednesday/...
230 PM Wednesday update... overall...the same synoptic-scale pattern should remain
at play...with a western north amer ridge axis...a persistent eastern
Canadian vortex...and an attendant l/WV trough axis southward through
the eastern Continental U.S.. this should ensure a continuation of below climatology
temperatures for early Feb (highs no better than the low-middle 20s...with
overnight readings below zero on several occasions).
More uncertainty creeps in regarding the track/intensity of a
potential storm system from sun ngt-Mon. Although most guidance
from the 00z Wednesday cycle brought a well developed cyclone east-northeastward
from the Ohio/Tennessee valleys...with resultant accumulating snowfall in
cny/NE PA...the 12z Wednesday runs of the GFS/ec have trended much
weaker/more suppressed with this system. Given the strength of the
aforementioned vortex to our north...this scenario is not out of the
realm. At this early juncture...prefer not to make rash changes based
on a single model run. Thus...we'll just ease probability of precipitation back into the
chance category (40-50%)...which conveys the overall lack of
confidence...but also gives the opportunity to easily bring probability of precipitation
upward again at a later time...if future model runs latch back onto the
"snowier" scenario for our region.
Beyond this time frame (tue-wed)...it simply looks very cold (max
readings perhaps not getting out of the teens)...with only scattered flurries
or snow showers foreseen...within an overall dry air mass.
Aviation /00z Thursday through Monday/...
VFR conds will prevail through the period. Hipres slides east later tonight
and on Thursday allowing a clipper system to aproach the area. At this time it
looks as though the snow and lowered visibility and ceilings will arrive just
beyond this taf period. Light winds this evening will become southeast at around 10
kts or less Thursday as the wave aprchs.
Thursday night...IFR restrictions likely in snow.
Friday...occasional restrictions (mvfr/ifr) in snow showers.
Friday night...possible restrictions (mvfr/ifr) in snow showers...especially in
Sat...Sat night...and most of sun...VFR.
Sun night and Monday...possible restrictions (mvfr/ifr) in snow.