Area Forecast Discussion
Issued by NWS -- Remove Highlighting --
-- Discussion containing changed information from previous version are highlighted. --
FXUS61 KPBZ 181742
Area Forecast Discussion
National Weather Service Pittsburgh PA
142 PM EDT Sat Mar 18 2017
Mixed precipitation is expected today and tonight as low
pressure crosses the region. Building high pressure should
return dry weather later Sunday.
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Fog has thinned at most locations save for near DUJ, where
improvement is expected shortly. Showery precipitation will
begin to blossom over the next few hours as the stacked low
enters the region. Much of it will begin as rain or at most a
rain/snow mix, with snow becoming a bit more prevalent with time
as cold advection increases. Snow accumulation should be nearly
nonexistent this afternoon given the warm boundary layer and
lack of strong low level lapse rates. Temperatures were modified
using near-term guidance, with minor changes overall.
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/...
The upper low is progged to slowly shift SE of the area by late
tonight as the surface low dissipates. Snow showers are expected
with cooling temperatures, and these are expected to gradually
taper off by late tonight. Around an inch of snow is expected,
with 1-2 inches toward the higher terrain of WV/MD/PA. An
upslope component is expected, though model sounding progs show
most of the moisture below the snow growth region which should
limit efficient snow accumulations. The ridges could also see a
period of freezing drizzle Sunday morning as moisture in the
snow growth region dries out, but low level moisture lingers.
Clouds should decrease late Sunday as high pressure builds in.
Clouds and precip chances should return Monday with the approach
and passage of a cold front, though with limited upper support
maintained mainly chance pops with it`s passage. Low precip
chances could continue S of PIT through Tuesday morning as a
surface wave moves along the front S of the area.
.LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/...
Dry and cooler than average weather is expected through midweek
as surface high pressure builds under a NE CONUS upper trough.
Precip chances and warmer temps should return Thursday night
and Friday as warm advection ensues ahead of an approaching
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
-- Changed Discussion --LIFR restrictions remain entrenched at DUJ at 17Z, while
conditions have risen to VFR at ZZV. Quite a spread in ceilings
should continue across all terminals this afternoon, with the
MVFR/IFR ceiling line creeping up to the vicinity of the
Pittsburgh metro area. Showers will move into the region this
afternoon from both the northwest and south, with precipitation
continuing to hang on across eastern terminals during the
evening hours. With little change in airmass, have dropped all
sites back to LIFR ceilings by around midnight. These low
ceilings should persist into Sunday morning, and with high
pressure moving into the area, the drier airmass should allow
improvements to IFR towards the end of the 18Z TAF period.
VFR conditions should return to all terminals at least briefly
on Sunday night before the potential of restrictions develops
once again late Sunday night. Another chance for widespread
precipitation will come Monday and Monday night.
-- End Changed Discussion --