Area Forecast Discussion
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FXUS61 KPBZ 262140 AAA
Area Forecast Discussion...UPDATED
National Weather Service Pittsburgh PA
540 PM EDT THU MAY 26 2016
Warm temperatures with shower and thunderstorm chances are
expected through the holiday weekend.
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
540pm update...showers had developed ahead of weak shortwave, but
are finding it hard to maintain structure as warm air aloft is
providing a cap. With sunset, expect any lingering activity to
dissipate. Another shortwave is expected to cross Ohio later this
evening and then Western Pennsylvania overnight. Latest models are
showing some scattered development with this energy, however 18z
models seem to be overdoing precipitation with this feature.
Looking closer at latest mesoanalysis from SPC, the most unstable
air remains well to our southwest where this afternoon`s MCS set
it course toward. Additionally, atmospheric trends are showing a
slow stabilization over the area, which will only be increased
with dusk. Have limited pop coverage overnight and kept them in
the slight chance range. Also adjusted cloud cover and modified
temperatures with the latest hires numbers.
.SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY/...
Minimal day-to-day change expected through the period as the
forecast area remains parked under a eastern CONUS ridge.
Temperatures will be 10 to 15 degrees above seasonal levels with
dewpoints in the low to mid 60s. Diurnal chances for
showers/storms can be expected each day with daytime heating but
there does not appear to be any significant features to focus
activity until late on Sunday.
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
The eastern CONUS ridge is progged by ensemble guidance to shift
east off the coast by early next week. Mainly diurnal shower and
thunderstorm chances are expected in the moist, unstable
atmosphere west of the ridge through much of the long term
period. Models differ on the handling of a low across the
Carolinas by mid week, and the northern extent of any associated
precip. Used adjusted Superblend guidance through the period to
account for the uncertainty and varying operation model solutions.
Temperatures are expected to remain above seasonal levels.
.AVIATION /22Z THURSDAY THROUGH TUESDAY/...
Prevailing VFR is anticipated through the period, expect where a
shower or thunderstorm passes over a taf location this afternoon
and again on friday. At this point, have only maintained vicinity
thunderstorms in KLBE, KFKL, and KDUJ where the latest hi res
model guidance suggests convection could develop this afternoon.
Convective complex currently approaching western Ohio is progged
to slide southward, weakening on it`s northern flank. However,
added vicinity shower to ZZV to cover anything that may develop
briefly ahead of this system.
Moistening low levels may support the development of some fog
toward sunrise tomorrow depending on wind speed. Both the LAMP and
the experimental HREF suggest ceiling restrictions may be
possible north of PIT, so IFR conditions were introduced in those
Otherwise, VFR will return Friday. While there still may be a
chance for a shower or thunderstorm tomorrow afternoon, the
building ridge leaves little confidence for a vcsh or vcts mention
at this time.
.OUTLOOK /FRIDAY THROUGH MONDAY/...
Restriction chances in afternoon/evening convection will continue
through the holiday weekend.