Area Forecast Discussion
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FXUS61 KPBZ 301224
Area Forecast Discussion
National Weather Service Pittsburgh PA
824 AM EDT Sun Apr 30 2017
Warm this afternoon with isolated showers possible along the
ridges and north of I-80. A cold front will bring widespread
precipitation on Monday.
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
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 levels. An isolated shower or thunderstorm
is possible in the ridges and far north with differential
.SHORT TERM /6 PM THIS EVENING 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 /13Z SUNDAY THROUGH THURSDAY/...
Except for fog at ZZV/HLG/MGW dissipating shortly after sunrise,
VFR cumulus are basically all that will be expected for most of
today with clearing skies overnight, other than the possibility
of some stratus reforming around KDUJ. Gusty southerly winds to
20 kt could potentially bring some crosswind issues at sites
this afternoon. A cold front on Monday will likely bring
restrictions in showers/thunderstorms to all terminals, but with
the 12Z TAF issuance, PIT was the only site included due to the
30 hour length.
Restrictions are possible again with Thursday low pressure.