Scientific Forecaster Discussion
fxus61 kbgm 211912
Area forecast discussion
National Weather Service Binghamton New York
312 PM EDT Sat Sep 21 2019
generally fair, quiet and warm weather will continue through the
weekend. High pressure remains in control through tonight with
just patchy valley fog into early Sunday morning. Watching a
weak front that could combine with increasing instability and
moisture to produce a few showers or a thunderstorm both Sunday
and Monday afternoon. Staying mostly cloudy and cooler Tuesday
with a few showers north. High pressure and pleasant
temperatures return by Wednesday.
Near term /through Sunday night/...
latest GOES-east WV loop shows a pocket of very dry air in the
mid levels moving into west-central New York at this time. Visible
imagery shows Crystal clear skies across all of central New York and
NE PA. A few pop up cumulus clouds have formed back across
northwest PA and the western southern tier of New York. Based on these
trends and the latest cams; believe the weather will remain dry
and mostly sunny through the evening hours. Temperatures have
reached the mid-70s to lower 80s as expected, with light and
For tonight, a surface ridge of high pressure slides south into
the mid-Atlantic states, but will still hold enough influence
over our area for dry weather. The pressure gradient does begin
to increase, especially just off to our north and west.
Therefore, think that winds will be light and variable in the
valleys (where they decouple) but should see a steady, light
southerly breeze develop along the ridges/hilltops tonight.
Think that there will still be areas of valley fog, as dew
points slowly rise overnight. Not as cool, with lows only
dipping into the 50s east of I-81 and around 60 west.
Some minor changes for sunday's forecast based on the latest
guidance. Trends are for a weak disturbance and uptick in
moisture to move through our area Sunday afternoon. After any
morning fog Burns (by 9am) expect partly sunny skies. Instability
and moisture increase through the day, so that there will be a
slight chance to low end chance for a few showers or an isolated
thunderstorm by afternoon. Models are showing anywhere from
500-1000 j/kg of MLCAPE by afternoon, sfc dew points surging up
into the mid-60s and pwats around 1.6". Deep layer shear is
forecast to be low across the twin tiers and NE PA...but could
reach 25-30kts up north...this could aid in convective
development. Temperatures will be unseasonably warm,
potentially only a few degrees below the record high for the
date. Current forecasts give highs in the low to mid-80s.
Sunday night: the weak disturbance that could spark off a few
showers or t'storms during the day moves east, and our area
looks to be in between systems for this period. The main front
slowly approaches late at night and could bring a stray shower
across our far western/northern counties. Otherwise, mild and
humid with increasing south-southwest winds 8-15 mph. Overnight
lows only dip into the mid to upper 60s for most.
Short term /Monday through Wednesday/...
3 PM update...
A few isolated showers will be possible into Monday morning
ahead of an approaching cold front, then showers and storms
become more likely into the late morning and afternoon with the
passing front. Strong deep layer unidirectional shear will be
present ahead of the front, with very little cape to work with
at all. Some thunder will not be ruled out, and gusty winds
could be present in any showers and storms, but no severe storms
would be expected. Precipitable waters remain at around 1-1.5" but with a
progressive frontal passage and dry antecedent conditions, there
will be little concern for heavy rain.
Showers continue Monday night into Tuesday as an upper level
low tracks across the New York and Ontario border, with meager shear
and instability throughout the day. Any rain chances wrap up
Tuesday evening as high pressure begins to build in.
Temperatures peak in the mid 70s to low 80s Monday afternoon,
then fall back into the 50s Monday night with some of the higher
elevations possibly dropping into the upper 40s. Tuesday will be
the coolest day of the extended period as temperatures peak
only in the 60s, and possibly near 70f in the river valleys.
Overnight lows generally in the 40s are expected as skies start
to clear out.
Long term /Wednesday through Saturday/...
3 PM update...
Still looking at mainly dry conditions for the rest of the
extended as high pressure will be in control for much of the
period. The exception will be Thursday, with a cold front
tracking through and bringing a brief shot at some showers
during the daytime.
Looking otherwise warmer. Highs will generally stay in the 70s,
with lows in the 50s Wednesday night through Friday night.
Aviation /19z Saturday through Thursday/...
high pressure with mostly clear skies and VFR conditions
expected tonight and Sunday morning. Only caveat will be another
round of valley fog, mainly between about 06z and 13z Sunday.
This will likely impact the kelm terminal, with IFR or LIFR
restrictions in fog expected once again. At this time
restrictions from fog are not expected at the other taf sites.
Confidence in fog formation and impacts is moderate to high at
Winds will remain light and variable through tonight. Trending
toward light south-southwest winds late tonight into Sunday
Sunday afternoon...VFR, except early perhaps an isolated rain
shower or thunderstorm.
Sunday night through Tuesday...mainly VFR, but some restrictions
possible in showers as front crosses, especially Monday
afternoon and evening.
Wednesday...VFR conditions likely with high pressure building
in. May see some patchy fog at kelm in the morning.
Thursday...another front could brings showers and brief
restrictions to the area.