Area Forecast Discussion
Issued by NWS
FXUS61 KPBZ 291738
Area Forecast Discussion
National Weather Service Pittsburgh PA
138 PM EDT Wed Mar 29 2017
High pressure will ensure dry weather this afternoon before
another low pressure system brings rain to the region late
Thursday through Friday.
.NEAR TERM /THROUGH TONIGHT/...
With noon update, minimal changes were made to cloud cover and
hourly temperature grids as clearing occurs from north to
south. High pressure ridge building overhead will maintain dry
conditions this afternoon and tonight. Temperatures should warm
close to, if not slightly above seasonal averages.
Clear skies tonight, albeit not perfect for radiational cooling
with some surface wind, should allow for us to cool off early.
However, strengthening warm advection aloft should become a
limiting factor as we go toward Thursday morning. Thus, a non-
diurnal trend is forecast with lows close to seasonal averages.
.SHORT TERM /THURSDAY THROUGH SATURDAY/...
High pressure should keep the region dry through Thursday
morning, with guidance trending even a bit slower with the
arrival of precipitation. Still, will increase PoPs to likely by
Thursday night as deep, moist, southerly flow in advance of the
occluding low supports these values. Broad low pressure will
slowly slide eastward through Friday, maintaining rain chances
through much of the day. The weakening upper low will shift east
by Saturday morning, but lingering low level moisture may keep
widely scattered showers possible through the first part of the
day before building subsidence brings an end to precipitation.
Temperatures will continue to run slightly above seasonal
averages through the period, including on Friday, despite rain
with strong warm advection expected.
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
Very little change in the pattern is expected as model guidance
continues to show a series of low pressure systems ejecting out
of the southwestern CONUS and lifting toward the Ohio/Tennessee
valleys. This will maintain at least chance PoPs through midweek
outside of dry conditions expected Sunday. With some uncertainty
in low track and speed, a blend of guidance was used.
Temperatures will generally stay close to averages for early April.
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
VFR under clear skies will last through late this evening. High
clouds will begin to stream in from the west and southwest
overnight. Increasing low-level moisture will then begin to pool
west of the Ridges tonight, ahead of a warm front. This could
lead to some spotty MVFR around daybreak for ZZV or even
BVI/HLG, but confidence in this is low to medium. Otherwise, a
descent to low VFR is expected through the duration of the TAF
period, with rain chances increasing Thursday afternoon/evening.
Light and variable winds will gradually shift easterly by
Thursday, but generally remain less than 10kts.
Restrictions are likely again from late Thursday through
Saturday as another broad low affects the Upper Ohio Valley.