Scientific Forecaster Discussion
fxus61 kbgm 271226
Area forecast discussion
National Weather Service Binghamton New York
826 am EDT Mon Mar 27 2017
an upper-level disturbance will bring showers this morning. An
approaching cold front will bring another round of showers on
Tuesday. An area of high pressure, over eastern Canada, will
build across the region Wednesday and Thursday, to bring drier
weather. Temperatures will become mild both today and Tuesday,
then turn a bit more seasonable Wednesday and Thursday.
Near term /until 6 PM this evening/...
820 am update... temperatures have continued to rise slowly
across the region...and especially in Sullivan County where the
Freezing Rain Advisory has been allowed to expire. The threat
for freezing rain has ended with most of the precipitation now
in the form of rain. The rest of the forecast looks on track at
4 am update... bands of showers will rotate through cny/nepa
this morning, tied to a well defined short-wave crossing the
region. Temperatures are still hovering near 32f at this time
over Sullivan County NY, with at least spotty freezing rain
likely occurring. All available near-term temperature guidance
indicates a slow rise over the next few hours across the
Catskills, so an expiration time of 8 am for the Freezing Rain
Advisory still seems reasonable.
Regional radar loops still indicate occasional bursts of
moderate to heavy rain with some of the showers, but multi-radar
multi-sensor data, as well as local rain gauge data, show hourly
rainfall rates of 0.1-0.2", at worst. We expect a general
0.25-0.5" of rain across the region this morning.
During the afternoon, sinking motion behind the short-wave will
provide generally rain-free conditions, with just a few spotty
showers possible. As most of the area emerges into the warm
sector this afternoon, temperatures will become quite mild, with
highs ranging from the mid 40s over some of our far eastern
zones, to the mid-upper 50s in most other portions of cny/nepa.
Short term /6 PM this evening through Wednesday/...
415 am update... most of tonight will remain rain-free, with
again some isolated-scattered showers possible, mainly in the
pre-dawn hours. Temperatures will stay mild, with readings
holding up in the 40s-lower 50s.
As the next short-wave comes in Tuesday, it will drive a surface
cold front into New York/PA by late afternoon/early evening. Showers
will become fairly widespread with these features, with a few
thunderstorms not out of the question, especially across nepa.
We're again looking at a 0.25-0.5" of rain on Tuesday for much
of the southern tier and nepa, with lesser amounts to the north.
Any isolated convection could bring localized higher amounts.
Highs Tuesday afternoon will range from the 50s-lower 60s area-
Tuesday night-Wednesday, drier air will build in behind the
aforementioned cold front, with a surface ridge also nosing
southward out of eastern Canada. Temperatures will return to
more seasonable levels on Wednesday, with highs ranging mostly
from the upper 30s-mid 40s.
Long term /Wednesday night through Sunday/...
400 am EDT update...
no significant changes were made to the previous forecast
discussion. Models are coming to better agreement on the next
storm system that will move into the region early Friday morning.
This system will bring a chance for rain showers through Sat
afternoon. The best chance for precip will continues to be
Friday afternoon and evening. For more information please read
the previous forecast discussion below.
Previous forecast discussion...
Wednesday to Thursday high pressure at the surface with a ridge
aloft. Temperatures close to normal with highs in the 40s and
lows in the 20s and 30s.
Friday will be watching a strong storm for rainfall amounts.
Slow moving storm will move northeast from the Central Plains
into the Great Lakes Friday. Friday night it moves over our
region and reforms on the coast Saturday. The heaviest rain will
be with and ahead of the low Friday afternoon and night. Cold
air should stay to the north keeping all of the precip rain even
with the upper level trough Saturday. Any snow left will be
melted with warm moist air ahead of this storm.
Sunday will be in transition as flow GOES zonal and another
short wave and weak front approaches late.
Aviation /12z Monday through Friday/...
a low pressure system will drift to the north this morning and
rain showers will continue to push east. Expect mostly MVFR
ceilings and embedded IFR visbys through the morning, except for
kbgm which is holding at IFR. Flight conditions are expected to
improve by mid morning at all taf sites as showers move east out
of the area. Winds will become light and variable through the
A strong low-lvl jet is present over the region this morning,
thus low level wind shear will be a threat for all taf sites through at least
Monday night through Tuesday...restrictions likely from waves
of rain as frontal boundary waffles over the area.
Thursday night/Friday...restrictions likely in showers.
245 PM EDT Sunday update...the rain on snow melt event is
underway, and will continue into the upcoming week as
temperatures in the 50s-60s become more widespread across the
region. This warmth will also be accompanied by an increase in
surface dewpoints into the 40s.
Future rainfall amounts are roughly the same in today's model
runs, with basin averaged quantitative precipitation forecast up to an inch through Wednesday
morning. This along with the runoff of most of the 1 to 3 inches
of liquid water content across the headwaters of the upper
Susquehanna, Delaware and the Oneida-Syracuse river basin will
lead to high flows, and probably minor flooding at several of
the forecast gauge points in the Susquehanna and upper Delaware
Mmefs ensemble spreads are even more aggressive than our latest
operational hydrologic model runs, and show a potential for a
quicker melt on Monday with sharp rises to flood stage at the
headwater points, followed by secondary crests on Tuesday. In
some cases, the mean crests are to the moderate flood stage.
The confidence of a near worst case scenario outcome is quite
low at this time, but it will be important to keep these caveats
in mind as this event unfolds, and be prepared to react to
locally heavier rainfall and/or a rapid melt down of the snow
With forecast crests still over 48 hours away, there is still
time for further assessment, and no watch will be issued at this