Scientific Forecaster Discussion
fxus61 kbgm 192347
Area forecast discussion
National Weather Service Binghamton New York
747 PM EDT Tue Jun 19 2018
weak high pressure, will build across the region overnight, with
dry weather continuing. On Wednesday, a weak storm system and
frontal complex, will move across the mid Atlantic states, with
a few light showers affecting northeast Pennsylvania, and
possibly the southern tier of New York. On Thursday, high
pressure will build back in, providing another stretch of dry,
Near term /through Wednesday/...
2 PM update... strong dry advection this afternoon, via high
pressure building towards cny/nepa, has given US a sunny
pleasant afternoon, with much lower humidity.
This will lead into clear skies this evening. Later tonight, we
expect some mid and upper-level clouds to begin to advance into
the region, as increased west-SW flow aloft advects some moisture
into cny/nepa. The combined effects of ongoing low-level dry
advection into the early evening, plus increasing clouds late at
night, should preclude much if any valley fog development.
Lows by daybreak will range from the upper 40s-upper 50s.
Short term /Wednesday night through Thursday/...
215 PM update... Wednesday, a weak surface low is expected to
track eastward from the Ohio Valley across the mid-Atlantic
states, while at the same time, northern stream short-wave
energy in the upper levels drops from southern Ontario into the
northeastern states. The combined effects from these systems
could bring some light showers across the southern half of the
forecast area, with a good portion of cny expected to remain
At this point, we'll advertise scattered, mainly afternoon
showers across nepa, with just isolated showers possible across
ny's southern tier, and rain-free weather under partly sunny-
mostly cloudy skies over our northern zones (northern Finger
Lakes, Mohawk Valley, and southern Tug Hill zones). Afternoon
highs should range from near 70 over parts of nepa (under
thicker clouds and with possible showers), to the mid-upper 70s
from about the New York thruway corridor northward.
Wednesday night, as the aforementioned surface wave exits the
East Coast and the upper-level trough flattens out and heads off
to our northeast, showers will push out of the region during the
By Thursday, drier air should build back down across cny/nepa,
as eastern Canadian high pressure reasserts itself. As a result,
increasing sunshine is foreseen, with highs ranging in the 70s.
Long term /Thursday night through Tuesday/...
Thursday night through Sunday night:
High pressure over the region Thursday night will gradually
move east off the New England coastline as low pressure moves
northeast into the Ohio Valley. This low pressure will move into
the Great Lakes on Saturday and bring a warm front northward
through the region.
Moisture will increase with enough front along the front for
the development of some showers by Saturday morning. Operational
models and a majority of the ensembles are keying in on
Saturday featuring the highest coverage and chances for showers,
so we have increased pops to likely. On the flip side, we should
get into the warm sector by Sunday which looks to provide a
potential break with more in the way of scattered showers
ahead of a cold front which pushes through by Sunday night. Some
instability looks to be present for a few thunderstorms as well
both Saturday and Sunday afternoons.
In terms of temperatures, a gradual warming trend will be noted
the later half of this week. A favorable setup for radiational
cooling will lead to a chilly Friday morning with lows around
50. However, temperatures should rebound into the low 80's by
the afternoon hours given the modeled boundary layer
temperatures. While a warm front does come through Saturday,
showers will likely limit the temperature spread. Operational
models are likely to constrictive with the spread though and we
stayed close to the MOS guidance given the expected showery
nature of the precipitation and higher sun angle. Highs should
end up in the 70's after a warmer start near 60. Sunday will
feature similar temperatures.
Monday through tuesday:
Another area of high pressure will build into the region from
Canada. This should lead to sunny days with cool nights in the
40's and 50's with highs in the 70's. Current thinking is the
ensemble guidance may be a touch high with temperatures in this
period with a Canadian airmass moving in, so we went a couple
of degrees cooler.
Aviation /00z Wednesday through Sunday/...
730 PM update...
VFR/unrestricted conditions will continue throughout the valid
taf period which is 24 hours. Valley fog looks spotty at worst
as temperatures fall just to the dewpoint late tonight. Cooling
will be good with light and variable to calm winds tonight and
mainly clear skies.
At 15z, a 6k ft ceiling moves into the southern tier of New York and
avp. Some light showers with no restrictions move into avp
starting at 20z.
Wind Wednesday southwest at 5 kts or light and variable.
Wednesday night through Friday...generally VFR, though a small
chance for showers/brief restrictions is possible Wednesday
evening at kavp.
Saturday through Sunday...showers and restrictive conditions