Scientific Forecaster Discussion
fxus61 kpbz 200536
Area forecast discussion
National Weather Service Pittsburgh PA
136 am EDT Thu Jun 20 2019
showers and thunderstorms...some with heavy rain...will continue
through Thursday until the passage of a cold front. Dry and more
comfortable conditions are expected Friday and into the weekend.
Near term /until 6 am this morning/...
flash flooding and flooding remain a concern through the period
given the saturated soils, an ideal setup for training storms, and
efficient rainfall production associated observed high pwats and
deeper warm cloud depths. Main changes to the overnight period
included an update to pops and quantitative precipitation forecast based on current radar trends. The
rest of the forecast remains on track.
Short term /6 am this morning through Saturday/...
showers and thunderstorms and a continued flash flood threat will
persist Thursday until a cold frontal passage Thursday night. There
is a slightly higher risk of severe weather based of latest guidance,
however, marginal instability will be the limiting factor similar to
Long term /Saturday night through Wednesday/...
cooler and finally drier weather is expected Friday following the
cold frontal passage. A ridge will build eastward across the Great
Lakes region through the weekend, though guidance continues to
suggest some convection for parts of the area on Saturday and Sunday.
Rain will return areawide on Monday as the ridge shifts east and yet
another series of disturbances impact the region.
Temperatures will increase to near average under the ridge this
weekend, with slightly above average temperatures to start the work
Aviation /06z Thursday through Monday/...
a medium confidence forecast at least through the morning hours then
it rises to high the balance of the forecast.
Scattered showers should stay VFR until the column saturates as we
move into the early morning hours when IFR and low end MVFR clouds
will develop /as the case as 24 hours ago/. Highest confidence in
IFR cigs reside at fkl and hlg, elsewhere tried to tempo MVFR/IFR
during the 9-13z window. Lowest confidence of IFR cigs resides at
Cigs will lift to a broken cu field by mid morning then stay there
for the balance of the day. There should be a lull in the
precipitation from dawn through early afternoon. As a cold front
moves through showers and thunderstorms will develop after 16z from
west to east. Best shot of an Airport seeing IFR weather in vis
restrictions arrives between 20-24z. In wake of the front west-
northwest wind should keep cigs and vis MVFR save for fkl and duj. A
heavier shower Post frontal could drop an Airport to IFR briefly,
but that temporal resolution can be hashed out in upcoming forecasts.
Wind will be light through the morning hours then between 5-10kts
from 220-240 this afternoon. Direction veers to the northwest
/290-320/ after 2z as the front moves through. Gusts should stay
below 20 kts until tonight. Sustain speeds will stay below the 12 kt
no widespread IFR weather is forecast until Sunday when a upper level
Coshocton will teeter just above flood stage through the weekend
given all of the rain locally and upstream in the Muskingum basin. In
addition, this will cause high flows on the Tuscarawas river at
Newcomerstown and New Philadelphia through at least Saturday. As of
now, both points are forecast to stay below flood stage. Lastly, with
all the rain over the past week, this has created high flows at a
few points along the Allegheny river (rimer, Mosgrove, and
freeport). At this time, action stage is as high as they will go.
Maryland...Flash Flood Watch through this evening for mdz001.
Ohio...Flash Flood Watch through this evening for ohz039>041-048>050-
PA...Flash Flood Watch through this evening for paz013>016-020>023-029-
WV...Flash Flood Watch through this evening for wvz001>004-012-021-