Area Forecast Discussion
Issued by NWS
FXUS61 KPBZ 182211
Area Forecast Discussion
National Weather Service Pittsburgh PA
611 PM EDT Sat Mar 18 2017
Crossing low pressure will generate rain and snow showers
through Sunday morning. More showers can be expected with a
Monday cold front.
.NEAR TERM /THROUGH SUNDAY/...
No major changes were needed for the early eve update as cutoff
low pressure aloft is shunting a cold front across the Upper
Ohio Region. Expect numerous rain, and eventual snow showers to
continue through the eve hours with focus toward the ridges as
the night deepens. Snow accumulation is expected to be limited
to an inch or two for those areas given low inversion levels.
One possible concern is freezing drizzle, at least along the
ridges, as mid level ice crystals diminish with the encroaching
Residual snow shower activity should diminish through Sunday
morning and clouds diminish during the afternoon as high
pressure builds. No change was made to the sub-average
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
Dry weather continues Sunday night as the ridge crosses. The
next front will approach Monday and arrive during the afternoon
and evening hours. Kept PoPs in the high chance/low likely
range with only modest upper level shortwave support.
Precipitation will be almost all rain, save for a few possible
snow showers as precipitation wanes Monday night. Low PoPs were
maintained across the south on Tuesday as a weak wave causes the
front to briefly stall. Drier air and clearing will work in from
the north during the afternoon.
After a cold Sunday night, temperatures will return to more
seasonable levels through Tuesday.
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
Dry and cooler weather will continue through the midweek period
underneath high pressure, with temperature moderation Thursday
as flow begins to turn more southerly. Precipitation chances
return for Thursday night and Friday as warmer air and moisture
build ahead of the next trough. A frontal passage on Saturday
will bring more rain chances.
.AVIATION /22Z SATURDAY THROUGH THURSDAY/...
Upper low will continue to piviot east-southeastward with time this
evening, transitioning what precipitation that remains to snow in
cold advection/northwest flow. This should allow for deterioration
to IFR/LIFR cigs for most of the terminals overnight as already
indicated upstream and in sref probabilities. Some patchy drizzle is
possible but widespread confidence is too low for inclusion at this
time. Overall, think most notable restrictions will be in ceiling
and not visibility though some reduction is possible through Sunday
Gradual improvement is expected through Sunday as high pressure
Next chance for widespread restrictions will come with the
passage of a system Monday eve/night.