Area Forecast Discussion
Issued by NWS Binghamton, NY
FXUS61 KBGM 240734
Area Forecast Discussion
National Weather Service Binghamton NY
334 AM EDT Mon Apr 24 2017
High pressure is moving off the New England coast, yet it will
still manage to keep dry and mild conditions going today with
highs in the 60s to near 70. Late tonight through Tuesday,
light rain will move into the region, as a weak storm center
tracks up the eastern seaboard. A few showers may linger into
Wednesday morning east of Interstate 81.
.NEAR TERM /THROUGH TUESDAY/...
315 AM Update...
Departing high pressure will still have enough influence for
one more dry day, before showers move in tonight into Tuesday
courtesy of an extension of a low pressure system centered over
A few high thin clouds currently reside over the Twin Tiers to
Catskills, but overall the sky is mostly clear. It is not quite
a chilly as last night yet radiational cooling is still
occurring for the usual spots. There is a valley-to-ridge
spread in temperatures, with the surface inversion being quite
shallow. At 3 AM, Upper 30s can be found in Cortland, Norwich,
Sidney, Elmira and Rome. However, it is still upper 40s in Avoca
PA and for the hilltop of Binghamton airport.
Surface high pressure is exiting off the New England coast, yet
will still have enough of an influence along with the resident
dry air mass to keep our weather dry today. Variable wind will
become light east-southeast, but not enough to bring in much of
a marine influence and thus most of the region will still get a
good deal of sunshine allowing temperatures to once again reach
60s-lower 70s. High clouds will start thickening, however, for
Wyoming Valley to Poconos of PA early-to-mid afternoon, and
into the Catskills by late afternoon. This is a hint of a
distant yet approaching system.
A compact upper low is currently dropping into the Southeast,
which is initiating a weak cyclogenesis around coastal Georgia.
That low will vertically stack, making its progress slow as it
moves up the Carolinas today through tonight, reaching the Outer
Banks by Tuesday. Despite being centered so far away, aloft a
vorticity lobe will extend from it up through our region along
with increasing moisture through the mid-to-upper levels
especially late tonight through Tuesday. It may also be preceded
by one or more embedded shortwaves. Initially, resulting rain
will struggle to reach the ground due to dry low level air and
surface ridging, but enough top-down moistening will eventually
occur allowing showers to break out. Everyone will end up
getting some rain out of this, especially during the day
Tuesday, but amounts will be higher generally southeast of a
Sayre PA to Binghamton-Oneonta NY line. A few tenths of an inch
or so will be possible in Northeast PA to Catskills NY through
Monday now looks rain-free, as the models have slowed the
arrival of the next system from previous runs. Clouds should
thicken up during the afternoon, though, especially across NEPA
and the Catskills. Afternoon highs will range in the 60s, with
some of our Lake Ontario plain and central southern tier zones
perhaps reaching 70, as sunshine prevails longer in these areas.
Given the clouds and precipitation, Tuesday will be cooler, with
highs in the 50s-near 60.
.SHORT TERM /TUESDAY NIGHT THROUGH WEDNESDAY NIGHT/...
The area will continue to be affected by a coastal low Tuesday night
into Wednesday. In fact, forecast models continue to trend a
lower slower with the departure of this system and its
associated rain and showers over the region.
To begin the period Tuesday evening, the low will be near the
North Carolina / Virginia coast with a deep layer SE flow of
moisture continuing to bring periods of rain and showers into
the area...heaviest and steadiest east of I-81. This will
continue to be the trend through most of the night as the back
edge of the precip look to only move east slowly.
Heading into Wednesday, there still could be some lingering rain and
showers in the morning...especially from around I-81 east as
the area will be situated in the deformation zone along the
northern and western periphery of the vertically stacked low
which will be situated near the Delmarva. Expect any lingering
rain/showers in the morning to taper off in the afternoon but
with mostly cloudy skies continuing through most of the day.
Additional rain amounts from Tuesday evening until the rain ends
Wednesday should not be too heavy...possibly a quarter to half
inch in spots over the Poconos and Catskills with less farther
north and west. Highs Wednesday will range from the 60s east to
around 70 across the Lake Plain.
Wednesday night, coastal low continues to move away off to the
east with a southerly flow of warm advection already setting up
ahead of the next system approaching from the west. This will
result in mild overnight lows mostly in the low to mid 50s.
.LONG TERM /THURSDAY THROUGH SUNDAY/...
330 am Update...No major changes were made to the long range
forecast with this update...just some tweaks. The period is
still progged to feature above average temperatures with most
days seeing the chances for showers or storms...though forecast
details remain uncertain. For further information, see previous
Previous Discussion...A narrow ridge of high pressure will
allow strong large scale subsidence to dominate the region most
of Thursday. The ridge will usher in a much warmer air mass with
temperatures climbing into the mid to upper 70s, close to 80
Thur afternoon. Boundary layer moisture will also increase, with
sfc dwpts into the upper 50s and lower 60s, which will allow
the instability to rise ahead of an incoming front. This next
front will slide in from the west later in the day Thursday and
Thur night, and interact with the unstable air mass to produce
showers and thunderstorms. This cold front will not have a whole
lot of punch with it as the parent low pressure will remain
well to the north and move quickly into Quebec. The front will
wash out later in the day Friday, but still be capable of
tapping into lingering instability to trigger a few showers and
storms. Another push of warm/moist air will be felt into the
weekend as the broad upper ridge over the sern US expands and
lifts to the north. The lingering boundary will lift slightly to
the north and remain capable of tapping into the unstable
air...with continuing chances of showers and storms.
.AVIATION /07Z MONDAY THROUGH FRIDAY/...
VFR/unrestricted conditions can generally be expected 06Z Mon
through 06Z Tue. The only possible exception is that a brief
window of valley fog could occur at KELM around 10Z-12Z this
morning, though due to the dryness of the air mass it is not
considered likely and thus not included the TAF. Under high
pressure, surface winds will be light and variable, eventually
becoming east or southeast around 4-8 knots late afternoon
Tuesday through Tuesday night...Restrictions possible, as
showers move across portions of the region.
Wednesday through Wednesday night...VFR, other than a brief
restriction/shower still possible early morning for KBGM-KAVP.
Thursday through Friday...Restrictions possible, with at least
scattered showers anticipated along with a chance of thunder.