Area Forecast Discussion
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FXUS61 KPBZ 220755
Area Forecast Discussion
National Weather Service Pittsburgh PA
355 AM EDT Sat Oct 22 2016
Cool and unsettled weather is expected through Saturday with a
crossing upper level disturbance. Dry weather should return
Sunday under high pressure.
.NEAR TERM /THROUGH TONIGHT/...
Rain associated with the deformation band from large deep low to
our east is quickly eroding. As this precipitation forcing winds
down, mesoscale effects come more into play. Moisture convergence
parallel with the long axis of Lake Huron is extending southward
over Lake Erie. This lake-to-lake fetch is funneling rain showers
into northern and eastern Ohio currently, but will gradually
shift to the east, as winds slowly back later this morning. After
a break in precipitation early this morning, chances will return
across the Pittsburgh metro and downwind into the Ridges through
at least midday.
Low-level temperatures continue to fall at this hour and this is
translating to the surface, bringing near-surface temperatures
into the upper 30s and low 40s. As temperatures continue to dip, it`s
reasonable to expect some snow showers in the high terrain of WV
and MD. Considering how warm we`ve been, any accumulation should
be minimal and on grassy surfaces.
An tightening pressure gradient and mixing in cold advection
should also result in gusty winds especially in the higher
terrain, where gusts around 40 mph are expected. At this time,
have not hoisted an advisory but have mentioned the wind gusts in
the HWO. Low temperatures should be near the seasonal averages.
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
Sunday will begin dry as high pressure tracks well to our south.
Deamplifying flow aloft and gusty southwest winds will allow
clouds to decrease and push afternoon temperatures back up to
Clouds will begin to increase again late in the day ahead of a
quick-moving surface low/midlevel shortwave dropping across the
Great Lakes. The best chance for showers late Sunday and Sunday
night will lie north of Pittsburgh where the best low-level
convergence will be seen, with some isolated activity possible
along the ridges. The low will drag a front across Sunday night,
which will bring temperatures back to below normal. Monday will
feature lingering clouds in northwest flow, most numerous across
the north, where a few isolated showers may continue. Skies should
begin to clear Monday night as surface high pressure and upper
.LONG TERM /TUESDAY THROUGH FRIDAY/...
Continued ridging aloft will maintain dry weather into Wednesday.A
digging trough will cross the Mississippi River and begin to
impact our region during the late week period, with our next
decent chance of rain. The models differ on the fate of this
trough at the end of next week, lending much uncertainty to
precipitation chances and amounts. Temperatures will be near or
just a bit below climatology through the period.
.AVIATION /08Z SATURDAY THROUGH WEDNESDAY/...
Generally seeing MVFR conditions this morning as low-level
moisture wraps around the parent low to our east. Expecting a
gradual improvement through the day, but downlake areas should
improve slower, due to the continual feed of low moisture into the
Expect VFR conditions to be realized first at ZZV and slowly
further south and east away from Lake Erie through Saturday.
Expect wind gusts of 25 to 30 kts as the mixing deepens via cold
advection at the top of the layer.
.OUTLOOK /SATURDAY NIGHT THROUGH WEDNESDAY/...
Periodic restrictions can be expected until high pressure
approaches the region in the wake of a late Sunday/early Monday
shortwave and associated weak front.