Area forecast discussion
National Weather Service Binghamton New York
1155 am EDT Tuesday may 21 2013
Synopsis...
a warm and humid weather pattern has set up across the area and
will continue through Thursday, with high temperatures near to
just above 80 and lows mainly in the 60s. Scattered showers and
thunderstorms can be expected. A cold front will track across the
area Thursday night with showers and thunderstorms. Much cooler
weather will follow behind the front Friday and Saturday.
&&
Near term /until 6 PM this evening/...
1100 am update...area of scattered showers and thunderstorms that
tracked across northern County Warning Area at middle morning is now over eastern New
York. This activity developed in the vicinity of a warm front along
with a passing middle level short wave. Activity has now diminished
to a few isolated showers in the lake plain.
Temperatures late this morning are already in the middle 70s to lower 80s
with 100mb mixed layer convective available potential energy at 1000-2000 j/kg over the twin tiers.
Area will continue to destabilize through middle afternoon with
convective available potential energy approaching 2500-3000 j/kg, very unstable. Upstream
soundings show and elevated mixed layer which the model soundings
indicate may advect into central New York this afternoon. The instability
is in place over the region but we lack strong forcing mechanism
or enough deep layer shear to support widespread severe weather. A
weak warm front will remain over northern New York and possibly drop slightly
south this afternoon which could help initiate convection. Another
feature apparent on satellite is over eastern Ohio/western PA,
this boundary may also trigger activity this afternoon, some of
the mesoscale scale models indicating this scenario. Will continue
with increasing probability of precipitation this afternoon/evening into the high chance/low
likely along with the threat for isolated severe weather with
damaging winds and large hail.
620 am update...
quick update to add probability of precipitation in for thunder across far northern zones early
this morning. No other changes needed at this time.
320 am update...
warm front located across northern zones at this time. Weak WV is responsible for
sparking off convection, mainly north of the New York thruway however a
few pin-prick storms are developing further to the south.
Warm front will leaving County Warning Area in warm sector for a time this afternoon with dewpoints
climbing into the 60s and maximum temperatures in the 80s area-wide with valley
locales into the mid-80s. This will lead to instability increasing
through the day, though how much remains to be seen. 00z NAM indicates convective available potential energy
on the order of 2000-3000 j/kg while 00z GFS showing around 2000
j/kg. This will be plenty of instability to generate tstms, however
trigger will be lacking until closer to 00z when WV rounds the upper level
trough.
Latest models showing warm front sinking back through the area which would
likely provide a trigger for afternoon convection. In addition, ongoing
convection along with wind shift may lay out boundaries drg the day today.
Have kept chance probability of precipitation through a good portion of the day with scattered rain showers/thunderstorms and rain
expected and after 21z as WV gets closer, have increased probability of precipitation to likely
across northern zones.
Potential exists for a strong to an isolated severe storm this afternoon with
anything that is able to form. Expecting mostly pulse thunderstorms today with
meager wind fields.
&&
Short term /6 PM this evening through Thursday night/...
320 am update...
WV will ride up along the front tonight along with shortwave topping the
ridge. Have continued likely probability of precipitation across northern zones through 06z tonight with a
gradual decrease after this time. Convective available potential energy remain elevated leading to
thunder continuing.
Shower and thunderstorm chances will continue until frontal passage late Thursday night. Uptick
in activity drg the afternoon hours and have bumped probability of precipitation to likely during each
day. Potential continues to exist for strong to severe storms tomorrow and
Thursday.
Frontal passage occurs by midnight Thursday night. Likely probability of precipitation are expected just along
and ahead of the front then taper off to chance after 06z Friday.
&&
Long term /Friday night through Tuesday/...
at the start of the extended...deep upper-level troughing will be
working off the East Coast with strong high pressure building
southward across Great Lakes from central Canada. As this
occurs...strong blocking south of Greenland will result in only
a slow eastward migration of the exiting upper trough across New
England and the Canadian maritime provinces. This will ensure
arriving high pressure will dominate through the period with
little to no precipitation expected. With a dry airmass firmly in
place...expect a fairly wide diurnal range in temperatures with
overnight lows easily falling into the upper 30s and lower
40s and highs only reaching into the lower to middle 60s. From
this Vantage Point...it seems reasonable that conditions will
become favorable for frost formation through the weekend and
headlines will likely be needed at some point.
&&
Aviation /16z Tuesday through Saturday/...
12z update...
a lower confidence forecast during the taf period in regards to
exact timing and placement of thunderstorms...but outside of any
thunderstorms mainly VFR overall. Outside thunderstorms light and
variable wind becoming west-southwest at 5-10 knots...then back to
variable tonight. Weak wave will carry through the area this
afternoon...along lifting surface boundary...and heating of
unstable atmosphere sprouting some thunderstorms. Tempo groups
assigned to the best potential times for each taf site
accordingly /except kavp/. Additional storms will be possible with a
stronger wave this evening...as currently depicted via prob30
groups.
Outlook...
Thursday/Thursday night...MVFR possible in showers/thunderstorms.
Fri/Sat...VFR.
&&
Bgm watches/warnings/advisories...
PA...none.
New York...none.
&&
$$
Synopsis...pvn/rrm
near term...pvn/rrm
short term...pvn
long term...rrm
aviation...cmg
