Scientific Forecaster Discussion
fxus61 kbgm 241140
Area forecast discussion
National Weather Service Binghamton New York
640 am EST Fri Feb 24 2017
a warm southwest flow will keep temperatures above normal today
and Saturday. A warm front lifting through the area this
morning will bring showers and a chance for an isolated
thunderstorm followed by partly sunny and mild conditions during
the afternoon. A stronger system with widespread rain...gusty
winds and a chance of thunder is expected Saturday.
Temperatures will be cooler Sunday and Monday with scattered
Near term /until 6 PM this evening/...
main forecast concerns in the near term continue to be focused
around the incoming round of showers and isolated thunderstorms this
morning...the continued warm temperatures...and relatively
quiet conditions later today and tonight.
Fairly active weather pattern for the next 48 hours...which is
associated with a strong low pressure system currently over the
mid Mississippi Valley. A warm front extending to the east
across the srn Great Lakes will lift nwd this morning and
continue to be the focus for showers and thunderstorms. Current
regional radar shows an area of weak convection over wrn New York with
a branch extending to the east into the central srn tier of New York.
The most favorable bl/elevated instability is expected to
remain along and west of The Finger lakes...which is where most
of the convection will develop and track through the morning
hours as the warm front lifts north. Increasing deep layer
moisture along and south of the front will allow a few of the
convective cells to drop a quick quarter of an inch in a short
period of time.
The main story today will actually be the temperatures. As the
warm front lifts to the north...much of central New York and NE PA
will be situated within the warm sector. Strong warm air advection in the mid
levels will contribute to a deepening of the boundary layer
through the afternoon. As this occurs cloud cover should begin
to become more scattered and allow for supplemental solar
heating. Temperatures are still forecast to top out some 30
degrees above average for late February. Record highs will
likely be tied or broken today. Check out the list of records in
the climate section below.
Short term /6 PM this evening through Saturday night/...
short term concerns remain focused around the next batch of
showers and storms Saturday with the potential for strong winds
and locally heavy rain...and the change over to snow Saturday
evening with lake effect snow showers into Saturday night.
The southerly flow ahead of the deepening low in the Great Lakes
will continue to pump an unseasonably warm and moist air mass
into the region. The influx of deep moisture...pwats around 1
inch...along with strong layer lifting and strong boundary layer
winds will allow for the development of scattered-isolated
showers later this evening and into early Saturday morning.
These showers will likely not amount to much...and will likely
be focused in higher terrain areas due to an enhancement from
The surface low will lift newd from the central Great Lakes into
Quebec Saturday morning/early afternoon. As this happens the
parent upper trough will become negatively tilted and begin to
really dig into the northeast. Strong cold air advection on the back side of
this system will make a push to the east early Saturday
afternoon and act to tighten the thermal gradient between the
very warm/moist air to the east and the Arctic air blasting in
from the west. This strong baroclinic zone will be the focus for
showers and storms Saturday afternoon. Steep lapse rates and
sufficient instability...ml cape values around 500 j/kg and a
robust amount of deep layer moisture...pwats still around 1
inch...will all contribute to convective development. The two
main concerns with this line of convection remain the potential
for strong wind gusts and heavy rain. Instability will be
limited...but with heavy downpours the ability to Transfer
momentum to the surface will be enhanced. Winds aloft around
40-50 mph may be brought to the surface within the convection.
Model soundings continue to indicate a completely saturated
profile with a period of skinny cape available Saturday
afternoon along and ahead of the cold front...which would be
conducive for heavy rain...even if only for a brief period of
Model guidance continues to be in relatively good agreement in
the timing and placement of the heaviest rainfall...between
18-00z...with amounts around 0.5 to 1 inch through central New York
and ern PA. The threat for flooding appears to still be of
concern...although the ability for much of the snow pack to
lose moisture through the last couple of days may inhibit the
Cold air will barrel in from the west behind the front late
Saturday afternoon and evening with temperatures dropping
quickly from the 50s and 60s...into the 30s. As the cold air
advects in, the precip will begin a transition to a rain/snow
mix...and eventually to all snow by later in the evening. Winds
will still remain gusty Saturday night with sustained west winds
around 15 to 20 mph and gusts to 30 mph. The colder air moving
in will be cold enough to generate lake effect snow downwind of
lakes Ontario and Erie. 850mb temps around -13 deg c. Bl wind
trajectories are expected to be approximately 270 to 280...which
would place the Lake Ontario band north of the thruway. There
is also the potential for a Lake Erie band to make its way into
central New York...producing around an inch of snow through Sunday
We will be back to reality Saturday night with temperatures back
into the 20s and 30s...with gusty winds making it feel even
Long term /Sunday through Thursday/...
the long term period begins with a strong cold front off the
eastern Seaboard and much cooler temperatures poised over our
forecast area. The cool changeover will be short lived as
ridging will build out of the Ohio Valley into New York by early
Monday, pushing temperatures back up into the 40s.
The warming trend will continue Tuesday and Wednesday. Another
vigorous cyclone spinning out of the Midwest will pull warm and
increasingly humid air back into NY/PA. The result will be a
showery pattern with mild temperatures. Forecast highs for
Wednesday are well into the 50s.
A stronger polar blast will hit the region behind the cold front
early Thursday, and this cold regime appears as though it will
have staying power. The ul pattern over the Continental U.S. Will shift to
a mean trough over the east, with a steady flow of polar air
tracking down from north-central Canada toward the Great Lakes.
Aviation /12z Friday through Tuesday/...
ceilings have not dropped as expected...with all taf sites
sitting at VFR currently. There is patchy IFR/MVFR fog around,
but currently only impacting kbgm...and a cluster of showers and
storms over The Finger lakes...which will impact ksyr and krme
between 12-14z. May see a period of IFR vsbys with this
The warm front will continue to lift north after 15z, with
improving conditions south to north through the late morning.
This afternoon expect VFR/unrestricted conditions with gusty
south winds 10-12 kt, and gusts around 20 kt. Winds will remain
around 10 kt into this evening with a period of low level wind shear after 00z.
VFR conditions will transition to MVFR after 03z at kbgm, krme
and kith...while ksyr, kelm and kavp remain VFR tonight.
Saturday...restrictions likely, associated with a rainy frontal
Sunday...possible restrictions from lake effect snow showers at ksyr-
krme, with mainly VFR elsewhere.
Monday/Tuesday...possible restrictions in light rain or snow.
400 PM Thursday update...
Significant warm up with abundant snow melt will continue into
Saturday morning. Wind and above normal dewpoints will contribute to
significant snow loss tomorrow and Saturday. The best swe is
confined to higher elevations of Oneida County, the upper
Susquehanna and Delaware basins. Up to 1.5 inches may still be
released within the Susquehanna and Delaware, with 2 to 4 inches
coming out of the S. Tug Hill plateau into Oneida County.
Average swe throughout the basins are highly variable due to
variation of snow cover from nearly nothing along the river
channels to deep snow in the Mountain Woods. The other factor to
consider is rainfall associated with a strong cold front on
Saturday afternoon. European model (ecmwf)/GFS and NAM continue a slightly
downward trend of quantitative precipitation forecast through Saturday afternoon and progressive
nature of cold front suggests this is the way to go when
forecasting the quantitative precipitation forecast of this event. In our opinion, most areas
should see an inch or less basin average rain. Either way, quantitative precipitation forecast
and swe parameters are low confidence variables right now, but
they drive the river forecast center forecasts.
Oneida creek is the only river currently forecast to flood, but
several Susquehanna basin points are forecast to crest near flood
stage Saturday night and Sunday. Suspect an oversimulation of the
hydrographs right now as flooding projected by ensemble guidance is
outside the median confidence intervals, or in other words
approaching "worst case scenario". Have plenty of time to refine
these forecasts tomorrow and early Saturday. We did issue a Flood
Watch for Oneida County to assist the buf and aly offices
hydrologic services, as well as to support our own flash flood
service. This zone seems to be the most at risk of widespread
flooding due to the projected runoff conditions. If rainfall
increases further south, there is some chance we could expand
the Flood Watch into the upper Susquehanna by later tomorrow.
the next few days will feature near-record warmth. Here are the
daily records to keep an eye on for our official climate sites.
daily record highs 65/1906 24th, 66/1957 25th.
Record high minimums 44/1985 24th, 43/1957 25th.
daily record highs 63/1984 24th, 58/1956 25th.
Record high minimums 51/1985 24th, 43/1961 25th.
daily record highs 71/1985 24th, 67/1930 25th.
Record high minimums 50/1985 24th, 46/1930 25th.
New York...Flood Watch from Saturday morning through Sunday evening for