Area Forecast Discussion
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FXUS61 KPBZ 300534
Area Forecast Discussion
National Weather Service Pittsburgh PA
134 AM EDT Sun Apr 30 2017
Warm weather will continue through the day with the chance for
a shower or storm. A cold front will bring widespread
precipitation on Monday.
.NEAR TERM /THROUGH TODAY/...
Only minor adjustments to the overnight period. Hires model data
is still showing the possibility of a few showers developing
overnight with the crossing of a weak shortwave.
After the passage of the morning shortwave, 500mb ridge will be
well entrenched across the area and warm air will stream rapidly
northward. Would expect sunshine to make a return this afternoon
and temperatures to really jump in the broad warm sector. Models
still holding on to some cloud cover across the far north and
east, as the flow at the surface in these locales never loses
its easterly component until late in the day. With the rise in
temperatures, would also expect to see a bump in humidity
.SHORT TERM /TONIGHT THROUGH TUESDAY/...
Conditions will remain warm and dry overnight and clouds will
begin to fill back in toward Monday morning as atmospheric
moisture increases ahead of the next front. Still seeing some
timing difference in model solutions with the onset of showers
on Monday. Will lean more toward a slower solution since the
path of the upper level low is more toward the north on Monday
and the trough axis will really not show much of an easterly
swing until Monday afternoon. This will likely slow down the
eastward progression of the surface front. However, once the
large upper level system, which by Monday afternoon will be over
the Western Great Lakes, becomes negatively tilted, the surface
front will pick up forward speed and rush through Monday
afternoon. Showers and storms will develop along the front as it
moves eastward, with some enhancement in the strength of the
precipitation late day Monday, as an area of strong low-level
moisture convergence develops. This would likely be at a time
when the front has reached the eastern half of the area.
Front will clear the area Monday evening, with boundary
associated showers/storms ending as well. Strong cold air
advection will dive in behind the exiting system, bringing more
clouds and the risk for additional showers.
The cold air won`t be around for long on Tuesday, as winds swing
around to the southwest during the morning and warm air
advection will begin in ernest. The push of warmer air will also
disperse the cloud cover, allowing for plenty of sunshine by the
afternoon. Temperatures Tuesday will be near or slightly below
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
A southern stream trough will begin to spread moistures north
toward the region by later Wednesday, with shower chances into
the weekend as a mean mid level trough remains across the ERN
CONUS. Temperatures will trend 5 to 10 degrees below the
seasonal average through late week.
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
-- Changed Discussion --Stratus seems to have halted its southward spread as of 05z
early this morning with some holes noted in it along and north
of I-80. This stratus will likely start to erode from S-N as
boundary layer flow slowly edges to southerly by morning. After
that, VFR cumulus are basically all that will be expected for
most of Sunday with clearing skies going into Sunday night,
other than the possibility of some stratus reforming around
Restrictions in showers/tstms are expected with a Monday cold
front. Restrictions are possible again with Thursday low
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