Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Binghamton New York
800 PM EST Thursday Dec 25 2014
high pressure building over the southeastern states will bring dry
mild weather to the area through Saturday. Temperatures will be
well above normal for late December with highs in the 40s and
lower 50s and lows in the upper 20s to middle 30s. A cold front will
bring a chance for a few showers Saturday night into Sunday.
Colder weather will follow behind the front.
Near term /through Friday/...
800 PM EST update...
sadly a stratus deck is still dominating the region resulting in
overcast skies... but it is keeping temperatures across the region from
plummeting... so tonight it is a plus. Ceilings are around 4kft tonight...
but with the inversion expected to drop over night expect ceilings to
fall to around 2-3 kft by tomorrow morning. Expect mostly
cloudy/overcast skies to start off the morning due to a thin
sliver of moisture. Ceilings are still expected to slowly break apart
tomorrow afternoon as winds aloft become southerly. The southerly
winds will create some downsloping and since we will have much
less moisture over the region than previous days... clouds should
break up around the afternoon. For more information please read
previous discussion below.
main forecast challenge for tonight will be whether any clearing
can occur in mild westerly flow regime. Satellite imagery over and
upstream of the area would seem to suggest little clearing with
thick cloud cover extending back across Michigan. There is some
disagreement among the models about the degree of low-level drying
and possible clearing that will occur later tonight... but given
current conditions and cloud cover climatology for this time of
year will lean toward the cloudier forecast. The clouds will help
to keep temperatures well above normal with overnight lows
generally in the upper 20s to middle 30s.
Short term /Friday night through Sunday/...
dry mild weather will prevail Friday through Saturday with high
pressure anchored over the southeast U.S.. expect some clearing to
finally develop during the day on Friday with partly to mostly
clear skies expected Friday night into Saturday before clouds
increase once again ahead of the next weather system by Saturday
afternoon. Temperatures will be well above normal through the
period. Have gone with a met/mav blend yielding highs well into
the 40s on Friday and approaching 50 in many places on Saturday.
The next cold front will move across the area early Sunday.
Chances for rain showers will increase from northwest to southeast
on Saturday night. A few rain or snow showers could linger Sunday
morning near or just behind the front. 850 mb temperatures fall to
around -8 Sunday morning over Lake Ontario which could be enough
for a weak lake response and a few light flurries or snow showers
southeast of the lake Sunday morning in Oneida / Madison or
Onondaga counties. Overall temperatures will be cooler Sunday but
still several degrees above normal with highs mostly in the 30s to
Long term /Sunday night through Thursday/...
cold Canadian high pressure will dominate the long range with a cooling
trend setting up for Sunday night through Tuesday as the colder
air filters in. This will result in temperatures falling to near to a bit
below average. Conditions generally look to be quiet however there
will be the potential for some lake effect from time to time,
especially heading into Tuesday and Wednesday as 850 mb temperatures
over Lake Ontario fall as low as -16 c. However since the low
level flow will be mostly anticyclonic, implying lots of dry air
and low inversion heights, this will limit the potential for a
significant lake effect event. Meanwhile storms coming up from the
south will most likely remain south of the region through the long
Aviation /01z Friday through Tuesday/...
moisture trapped under a lowering inversion...will cause
persistence of MVFR ceilings where they are already occurring...and
lowering into MVFR where ceilings are currently low end VFR.
However...that saturated layer also gets thinner overnight...with
some uncertainty as to whether /and when/ scattering out occurs.
Occurrence of MVFR ceiling should be least at kavp where moisture will
be most limited...otherwise expecting remainder of terminals to
develop and/or hang on to MVFR ceiling into the morning hours.
Straight model guidance has typically been much too optimistic
lately in regards to stratocumulus trapped under inversion...and
thus am preferring to use model soundings for anticipation of
continued ceilings /NAM model in particular/. West-northwest winds roughly 8-12
kts and diminishing tonight...then backing to west-southwest in the morning
which will serve to scatter out the MVFR deck with time due to
what is for most terminals...a downsloping flow. Expecting
areawide VFR by 18z. The MVFR ceilings tonight should be higher end.
While lower end MVFR...fuel alt request level...is not considered
likely...it is not out the question at kbgm later tonight.
Sat ngt-sun...restrictions possible with chance of rain-snow
Sun ngt-Mon...mainly VFR.
Tuesday...mainly VFR...except restrictions possible for ksyr and krme due to lake
effect snow showers.