Sunday, July 22, 2018, 2:54 AM EDT
Return to Local
Area Forecast Discussion
||Wed, Dec 31, 7:00pm EST
FXUS61 KPBZ 220459 AAC
Area Forecast Discussion...UPDATED
National Weather Service Pittsburgh PA
1259 AM EDT Sun Jul 22 2018
Periodic rain chance will continue through midweek with passage
of slow moving low pressure.
.NEAR TERM /THROUGH TODAY/...
The only real change to the overnight period was a reduction in
PoPs over a large portion of the area. The line of showers over
the far west should dissipate as shortwave energy shifts
southward and drier air aloft moves in. The far east will see
an expansion of showers as coastal low moves northwest, toward
SE PA, overnight.
Area will rest in between two surface lows today. The western
low will be associated with the persistent main upper low and
will rest over southern Ohio today. The eastern low will rush
northward this morning in the strong southerly flow aloft on the
eastern flank of the 500mb low. Showers this morning will be
mainly confined to the eastern edge of my forecast area and
will drift northward exiting by early afternoon. During the
afternoon hours, another area of showers will drift northward
from WV and spread across the southern half of my forecast area.
These showers will be associated with a moisture plume which
will drive northward on the eastern side of the weakening 500
low and its surface reflection. Rainfall this afternoon is
expected to be light, with the bulk of it occurring south of
.SHORT TERM /TONIGHT THROUGH TUESDAY/...
Unsettled conditions with periodic showers and a few
thunderstorms will continue through Tuesday as the
region will remain squeezed between the upper low/trough to the
west and a deepening ridge near the northeastern US coast.
Extensive cloud coverage will continue the trend of high
temperatures slightly below average and lows slightly above.
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
Minimal change made to the extended today with decent model
continuity with previous runs. Shower/storm chances will
continue daily as the upper low over Ohio continues south and
another upper low approaches southeastern Canada. The best
chance for areawide activity will be Tuesday night and Wednesday
with a surface cold front. Temperatures will be near seasonable
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
MVFR cigs are expected to develop overnight mainly from PIT N as
a wave of low pressure rotates around an upper low across the OH
Valley region. MVFR is also expected for OH ports with low level
moisture in place, with VFR S of PIT. A return to VFR is
expected from after sunrise through through early aftn.
Sct showers and isolated thunderstorms are also expected during
the aftn with the upper low in close proximity. Will not
mention thunder in the TAFs due to limited coverage N of PIT,
though will include PIT S where slightly better instability is
Periodic restriction potential continues through mid week with
the slow moving low and subsequent upper troughing.