Area Forecast Discussion
Issued by NWS -- Remove Highlighting --
-- Discussion containing changed information from previous version are highlighted. --
FXUS61 KPBZ 240535
Area Forecast Discussion
National Weather Service Pittsburgh PA
135 AM EDT Mon Apr 24 2017
High pressure should maintain dry weather tonight north of I
68. Low pressure tracking along the East Coast should result in
periodic rain chances east of I 79 for the start of the new
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
Surface ridging should maintain dry weather overnight north of I
68. A deepening low is progged to track toward the SE CONUS late
tonight, with an inverted surface trough extending to WV/MD.
Increasing moisture and ascent on the nrn periphery of the low
should return rain chances to areas S of I 68 overnight. Lows
should be near or a few degrees above the seasonal average.
.SHORT TERM /6 AM THIS MORNING 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 /06Z MONDAY THROUGH FRIDAY/...
-- Changed Discussion --Mostly VFR conditions are forecast over the next 24 hours. High
pressure will be moving off to the east, with upper level low
pressure over the Deep South. East flow in a developing inverted
trough will increase moisture along the ridges and areas mainly
south of I-68 today. Most rain chances will remain east of a
LBE-MGW line through tonight, although MVFR ceilings may affect
MGW by late afternoon/early evening. Other terminals will see
increasingly lower VFR ceilings. East winds will pick up to 10
to 20 knots by afternoon.
The next chance for general restrictions is expected with mid
week low pressure.
-- End Changed Discussion --