Area Forecast Discussion
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FXUS61 KPBZ 270500
Area Forecast Discussion
National Weather Service Pittsburgh PA
100 AM EDT Tue Sep 27 2016
High pressure will provide for dry conditions today. An upper low
will then return the chance for showers and seasonal temperatures
through the end of the week.
.NEAR TERM /THROUGH TODAY/...
Subsidence is beginning to take place as the boundary shifts off
to the east. With some mixing expected to continue, dewpoints
should continue to drop off, providing for dry and cloud free
conditions through the day today. However, some low level
moisture over the southeastern parts of our forecast area (south
of I-70 and east of I-79) may not mix out fast enough to preclude
some fog development early this morning.
With southwest flow continuing on the periphery of the broad cut-
off low over the northern Great lakes, and some slight warming,
temperatures should be very close to average today.
.SHORT TERM /TONIGHT THROUGH THURSDAY/...
Temperature advection will be quickly neutralized on Tuesday, with
warm advection resuming on the southeastern flank of Great Lakes
low pressure. As such, temperatures were forecast near the seasonal
The Great Lakes upper low is forecast to dig southward across the
Upper Ohio during the mid week period. As models are coming into
more consistent depictions, confidence in the forecast of
chance/scattered shower weather with sub-average temperature is
improving. Few changes were made to the prognosis for this period.
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
The aforementioned upper low is projected to fill/lift
northeastward by next weekend with zonal flow resuming over the
Upper Ohio Region. Predominately dry weather is thus forecast with
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
Any MVFR restrictions in stratus this evening should be short-
lived as a cold front completes its passage across most of the
region and brings in much drier air. Mid/high level clouds will
then continue for a few hours before skies clear. The one location
that is expected to have restrictions after midnight is MGW, where
the cold front may linger through the overnight hours. Although
stratus will lift, fog is expected to develop at MGW with
relatively light winds. By early afternoon on Tuesday, wind gusts
up to 20 kts are expected at all terminals, with clear skies
continuing through the day.
.OUTLOOK /TUESDAY NIGHT THROUGH SATURDAY/...
Upper-level low pressure will settle into the Great Lakes region
through the week. Flight restrictions will be increasingly likely