National Weather Service National Headquarters

• Home
• Site Map
• News
• Organization
• Search for: NWS All NOAA 

000
FXUS61 KPBZ 300555
AFDPBZ

Area Forecast Discussion
National Weather Service Pittsburgh PA
155 AM EDT Tue May 30 2017

.SYNOPSIS...
An unsettled weather pattern will continue through the week
as a series of cold fronts affect the region.

&&

.NEAR TERM /THROUGH TODAY/...
Only minor changes to the overnight period. Update of PoPs in
line with latest radar trends and hires model guidance. Radar
trends, and satellite as well, indicate a stabilizing atmosphere
as convection over Ohio is rapidly weakening. As the activity
moves closer to PA, it is dissipating. Model trends are showing
any additional rain overnight would be confined to the northern
half of the area, ahead of a weakening shortwave trough.

An area of low-level convergence will develop just east of the
area during the morning hours. The next shortwave, rotating
around 500mb low over Southern Canada, will approach the area
early this afternoon. With the most of the moisture confined to
the east of the region, in the proximity of the low-level
convergence, expect more widespread activity to remain near the
ridges, eastward. Will include PoPs across the eastern half of
the area today, due to the rapid atmospheric destabilization in
an area of warm air advection and increase in surface
dewpoints. Any convection that does develop should be scattered,
due mostly to the aforementioned instability and daytime
heating. In the absence of showers/storms, expect a decrease of
cloud cover with a drier air-mass slowly overspreading the
region from the west.

&&

.SHORT TERM /TONIGHT THROUGH THURSDAY/...
Dry and mainly clear tonight.

Next shortwave trough will approach the area Wednesday morning,
once again bringing the risk for showers and storms. Cooler air
aloft, and some modest instability will require the mention of
storms. Shortwave trough will swing through Wednesday night and
there will be a period of cold air advection into Thursday. Flow
aloft will become more zonal on Thursday and broad surface high
will move across the region. This should keep Thursday dry with
plenty of sunshine and seasonal temperatures.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
The unsettled pattern will continue through the long term.
Latest medium range model guidance is showing a weak cold front
approaching the area on Friday, then stalling as the flow aloft
remains zonal. Additionally, elongated trough will dig into the
Upper Great Lakes this weekend as ridge builds into Southern
US. This will put the area in a squeeze play and keep that
frontal boundary over the region through the weekend. Still a
lot to be worked out on timing and final location of front. By
the end of the period, forecast is made with even less
confidence as Great Lakes trough may deepen and cutoff by early
Monday.

&&

.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
General VFR and dry conditions are expected through the TAF
period as any shower/storm development should be primarily east
of KLBE.


.Outlook...
Restrictions are possible Wed under the upper trough, and again
Fri with another front.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...None.
OH...None.
PA...None.
WV...None.

&&

$$