Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Binghamton New York
734 PM EDT Friday Jul 3 2015
a low pressure system will move south of the area on Saturday and
bring a chance of showers for the Holiday. High pressure building
in behind the low should clear on the precipitation in time for
most fireworks shows Saturday night. Sunday looks fair under high
Near term /through Saturday/...
models continue to struggle with what is a rather weak system moving from
the Ohio Valley to the Delaware-Maryland-Virginia. Overnight runs pushed the precipitation nwrd and
increased the intensity...while the 12z models have generally
backed off...xcpt the GFS which may be suffering some conv
feedback gnerating heavier precipitation ahead of a WV streaking newrd.
Also...timing has slowed and now it looks like the first chance
for any light precipitation will be after midnight in the extreme south ad west.
For this grid update have lowered probability of precipitation to chance all areas...keeping
high chance to the south nearer the upper support. Have included
isolated trws over The Finger lakes in line with the NAM that shows a
bit more instability over western New York moving ewrd into the area in the
afternoon before weakening.
Temperatures remain below normal Sat afternoon with the clouds and scattered showers.
Short term /Saturday night through Monday night/...
models have not been running very consistent run to run the last
24-36 hours...this afternoon they have jumped back to a drier
forecast for Saturday night. Confidence is marginal at best with
the 12z runs now all showing the precipitation chances dwindle from early
afternoon through the rest of the evening...meaning much better
fireworks viewing is likely for the evening of the fourth. Trough
pushes east of the region Saturday night with shortwave ridging
moving into the northeastern Continental U.S. Sunday. Sunday and Monday
should be dry with the ridging in control...temperatures will rebound
above normal pushing into the lower to middle 80s for highs.
Long term /Tuesday through Friday/...
model uncertainty exists at a fairly high level through the long
term with models trending much drier late in the period. Model not
holding consistent timing for front passing through Tuesday and
Wednesday...all producing lower than average forecast confidence
for the period. GFS pushes the front through Tuesday night with
the Euro holding it until Wednesday morning or early afternoon. Have
kept probability of precipitation through this timeframe...but Tuesday during the day may
be mostly dry...with best chances Tuesday night through Wednesday afternoon.
Slightly more zonal flow behind the front. The latest models show
dry days for Thursday and Friday...have trended the forecast drier
for the Wednesday night through Friday period...if the trend
continues tonight the forecast will likely go all dry if the run
to run consistency is there for the 00z run tonight. Slightly
above seasonal temperatures likely through the period...upper 70s and
lower 80s for most.
Aviation /00z Saturday through Wednesday/...
the area will remain VFR throughout most of the evening starting to
deteriorate into mfvr ceilings as a trough current over PA moves into
the region overnight and into the morning. Kavp will see mfvr ceilings
first as it passes through 05-09z followed by kbgm at 07z then
kelm at 12z with visible staying VFR with light rainshowers. Ceilings and
visible will remain VFR for kith/ksyr/krme as the feature pushes
through 08-13z with light rainshowers...the added low level
moisture will help develop some afternoon showers throughout the
region with occasional MVFR ceilings as they move over the terminals
after 16z. The showers will die off for most locations with
ksyr/kith/kelm/kbgm having the greatest chance of continued
showers after sunset.
Weak surface pressure will keep winds relatively low...less than
10kts...shifting from a S-southeast to west-SW direction in the afternoon
to evening timeframe.
Sat night into Sun morning...showers will tapper off leaving
mostly clear skies allowing potential patchy River Valley fog with areas
of IFR visibilities possible Sunday Morning.
Sun through early Tuesday...mainly VFR.
Tuesday late into Wednesday...MVFR and isolated IFR restrictions possible in