Area forecast discussion
National Weather Service Binghamton New York
200 PM EDT Thursday may 23 2013
Synopsis...
a cold front will approach the region by this evening...then
slowly cross the area late tonight or early Friday. Showers and
thunderstorms will likely precede and accompany the front through
this evening...with showers then continuing behind the front later
tonight and Friday...along with much cooler temperatures.
&&
Near term /until 6 PM this evening/...
1010 am update...
forecast in fairly good shape this morning...only minor changes needed
at the present time. Regional radars showing an area of light
showers working northeast through the bgm forecast area on the heels of
a weak shortwave trough now lifting north through central New York with
latest water vapor imagery showing a notable dry slot now entering
western New York. So far current activity has displayed no convective
trends and as a result...have backed off thunder mention until
early afternoon.
Main concern going into the afternoon remains possible severe weather
development as long advertised cold front approaches from the
northwest. That said...forecast models continue to indicate only
weakly unstable conditions by this afternoon/evening which may be
a result of current cloud cover aloft. That said...the potential
does exist for model underestimation of this afternoon/S
instability as periodic breaks are expected to move into the
region later today. That said...RUC and local WRF BUFKIT and AWIPS
plan view forecasts show nearly 800 j/kg of MLCAPE by this afternoon
which may not be too far off if some clearing does move into the
area. The other thing that today/S setup has going for it is
decent dynamics aloft as upper divergence will be increasing
through the day as a jetstreak strengthens over the region in
confluent flow aloft. Considering 0-6km bulk shear vectors are
oriented nearly parallel to the arriving cold front...main
development will likely be linear in fashion with strong winds
likely being the biggest threats. Obviously a lot to monitor and
updates will be made as needed. Current thinking is today/S
activity will hold off until middle to late afternoon at the
earliest. Remainder of near term forecast looks to be in good shape
with middle to upper 70s expected for daytime highs.
545 am update... a band of -shra/isolated thunderstorms and rain continues to March across
the County Warning Area at this time...likely associated with an upper-level wave. We expect showers
to impact much of the region through 14-15z...followed by a lull in
precipitation for most of this afternoon.
Although a fair amount of cloud debris should be resident today over
the northestern states...ahead of the surface cold front...a few breaks of sun are
not out of the question during the early and middle-afternoon hours. This will
likely provide enough heating/destabilization to fuel another round
of rain showers/thunderstorms and rain late in the day...and especially this evening...as the front
itself apprchs. The latest rap/WRF/GFS consensus suggests the
potential for 500-1000 j/kg of cape this afternoon...along with improving
deep-layered shear...and some height falls aloft. Thus...organized
linear features seem plausible...with damaging winds the primary
threat.
&&
Short term /6 PM this evening through Sunday/...
555 am update... our model suite continues to trend slower/less
progressive...with the amplified upper-level trough to impact the region
through at least the first half of the Holiday weekend.
Post-frontal showers have been well advertised in our forecast for
Friday...along with much cooler temperatures...and nothing has changed in this
regard. In fact...readings Friday likely will hold about steady in the
Lower-Middle 50s...and may even edge downward a bit as the day GOES on.
We've nudged probability of precipitation upward a bit for Friday ngt/Sat...mainly in our eastern
zones...to account for the likelihood of a slower departure of
moisture/forced lift...as it now appears that a closer upper-level
system will linger along the coast at least into Sat.
Although drying/clearing skies now looks slower to occur...we
still anticipate that some clearing will make it into our western zones
by Sat/Sat evening. Thus...present indications are are that the best shot for
frost/freeze conds will be in the western half of the forecast area Sat night/early
sun am.
&&
Long term /Sunday night through Wednesday/...
Upper low slowly lifts nwrd out of new eng while a northerly flow of cold
air continues over the forecast area. Strong sun angle helps top modify
the air mass but it will still be cooler than normal for the
remainder of the Holiday weekend. Next chance of rain arrives late
Tuesday into Wednesday as the hi retreates and warm fnt over the Midwest
pushes NE. Much warmer air returns for Wednesday and with the fnt still
over northern New York and western new eng...possiblity of some trws through the end of
the period.
Model guidance in line with HPC guidance which was followed for this forecast.
&&
Aviation /18z Thursday through Tuesday/...
Upper low and surface cold fnt continues to push slowly east today. Scattered
conv is possible ahead of the fnt through the afternoon period flwd by narrow line
around the time of frontal passage. Gnrl VFR conds will prevail outside
of any trws...with MVFR ceilings and visibilities likely during the storms.
Bhd the fnt...very strong cold air advection will result in lowered ceilings and visibilities
in numerous showers. Expect little imprvmt until late in the period when some
mixing will help raise ceilings and visibility before the end of the period. SW
winds will be common ahead of the fnt...with a few gusts especially in vicinity of
trws. Bhd the cold fnt northwesterly winds expeceted.
Outlook...
Sat...possible lingering restrictions in lower cigs/-shra.
Sun - Tuesday...VFR.
&&
Bgm watches/warnings/advisories...
PA...none.
New York...none.
&&
$$
Synopsis...mlj
near term...cmg/mlj
short term...mlj
long term...dgm
aviation...dgm
