Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Binghamton New York
659 PM EDT Monday Aug 3 2015
scattered showers and thunderstorms this evening over parts of the
region, will diminish overnight. Hit and miss showers and storms
are anticipated again Tuesday afternoon, as an upper-level
disturbance tracks over the area. Mainly dry weather is expected
Wednesday, with weak high pressure in control.
Near term /until 6 am Tuesday morning/...
330 PM update... two short lines of convection will impact
portions of the forecast area late this afternoon into the early
evening. One will be over northeast PA and the western Catskills,
along and just ahead of a weak low-level trough/outflow boundary.
The second will impact the northern Finger Lakes, western Mohawk
Valley, and southern Tug Hill regions, ahead of the main surface
cold front. Despite the presence of the above mentioned
convergence boundaries, some upper-level jet dynamics, and decent
deep-layered shear (effective shear values of 25-40 kt),
thunderstorms are expected to remain hit and miss in nature, and
largely non-severe. This is due mainly to only marginal buoyancy
(ml convective available potential energy of 500-1000 j/kg) and weak middle-layer lapse rates (as
indicated by recent amdar soundings and Storm Prediction Center meso-analysis).
Elsewhere, showers/thunderstorms will be few and far between, as
drier more stable air has taken up residency, especially across
the twin tiers.
Showers/isolated storms may linger for a while later this evening
in our far southeastern zones (catskills and the Pocono plateau),
with activity finally departing after about 1-3 am.
Even though the ground will be wet in spots due to shower
activity, a well mixed environment in the boundary layer should
preclude much in the way of fog development overnight.
Short term /6 am Tuesday morning through Thursday/...
scattered convection should bubble up again Tuesday afternoon
(mostly over central ny), coincident with maximum heating, as
additional short-wave energy rotates around a closed upper low
over eastern Canada. Any activity that forms should diminish
quickly Tuesday evening, with mainly dry weather during the night.
Wednesday-Wednesday night look rain-free, with weak surface
ridging overhead, and negative vorticity advection/sinking motion
On Thursday, although some model differences remain, a broad
consensus would keep most of the shower activity, tied to the
next storm system/upper-level trough (approaching from the Ohio
valley), from our northeast PA counties southward, with central
New York staying mainly dry. More clouds/possible precipitation on
Thursday should keep high temperatures a bit lower (mostly in the
Long term /Thursday night through Monday/...
generally followed HPC guidance this period. The long term begins
with a weak trough extending from eastern Canada down through the
lower Ohio Valley. As a series of diffuse waves rotate through the
flow, a more defined cyclone is prognosticated to form over the lower
midatlantic region and track toward the Atlantic coast. While the
main low is too far south initially to affect US, the trough will
keep at least a slight chance for showers in the forecast through
much of the period. A cool high building down from Canada will
keep temperatures in the middle 70s on Saturday.
Aviation /00z Tuesday through Saturday/...
mainly VFR conditions are expected for this forecast period.
Isolated shower activity will dissipate over the next few hours,
and then winds will become light overnight.
A scattered to broken High Deck should preclude fog formation
Tuesday after...brief restrictions possible from scattered shra-tsra.