Area Forecast Discussion
Issued by NWS
FXUS61 KPBZ 231839
Area Forecast Discussion
National Weather Service Pittsburgh PA
239 PM EDT Sun Apr 23 2017
High pressure should maintain dry weather today. Low pressure
is expected to track along the East Coast, resulting in
periodic rain chances mainly east of I 79 for the start of the
new work week.
.NEAR TERM /THROUGH TONIGHT/...
Surface high pressure will hold dry conditions through today as
a cut-off low churns into the southeast U.S. High clouds will
begin to increase this afternoon, but a mix of sun and clouds
will be maintained through evening. Northward expansion of rain
will start to reach our southeastern zones near midnight. Beyond
that, given the continued southeastern drift of the parent low,
more favorable rain chances will be well confined. Increased
PoPs over the high elevations tonight, while continuing to keep
areas west of the Ridges dry.
High temperatures today will top out a few degrees above
normal. Lows tonight will be a bit trickier as clouds begin to
increase areawide, and easterly flow strengthens. This should
keep the mountains cool tonight, while downslope areas west of
the Ridges warm. These locations should stay near or a few
degrees above average.
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
The cut-off upper-level low will dig further into the
southeastern U.S. Monday. As this occurs, very little northwest
progression of rain chances will be achieved. Models hinting at
weak ascent streaming northward in the form of a deformation
band, but activity along this will largely be negated by the
presence of low-level dry air re-enforced by downsloping flow.
As a result, will keep a tight gradient of PoPs along the
Ridges, with only slight chance west.
The best chances of rain outside of the higher elevations should
come Tuesday as the low turns the corner and begins to fill over the
Mid-Atlantic. Strong easterly flow will continue to advect moisture
into the eastern facing upslopes, and some rain may be able to creep
east to west over the higher elevations. The weakening low will then
be pushed away by a building ridge through the upper Ohio Valley
late Tuesday, establishing areawide dry conditions by Wednesday
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
Ridging and rising heights in response to an approaching
Midwestern trough should result in dry and warm weather for mid
week. The flow is progged to amplify by late week as broad low
pressure develops over the western CONUS. One cold front will
stream through Thursday with showers and thunderstorms likely.
This system will then open the door to more disturbances keeping
the forecast wet through the weekend. Temperatures will be above
average through the extended.
.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
High pressure will maintain VFR and light northeast to east sfc
wind into Monday.
The next chance for general restrictions is expected with mid
week low pressure.