Area Forecast Discussion
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FXUS61 KPBZ 281723
Area Forecast Discussion
National Weather Service Pittsburgh PA
123 PM EDT THU JUL 28 2016
A series of crossing disturbances will keep showers in the
forecast through the weekend with humid conditions.
.NEAR TERM /THROUGH TONIGHT/...
Shortwave producing showers and embedded thunderstorms moving
northeast across region with bulk of rain now moving into and
across the ridges. Second shortwave now moving into West Virginia
with models differing on how far north and west thunderstorms will
be able to fire this evening. Based on current placement of storms
on radar and lack of low level instability due to morning rains,
have adjusted highest POPs and QPF farther south and east. This
still puts southeast ridges and portion of northern West Virginia
in line for possible heavier rainfall in thunderstorms, but it
appears bulk of stronger re-development may be east of the ridges
late afternoon and evening. Will continue to monitor. Only a
slight chance for showers along and north of I-80, with remainder
of region seeing a slow decrease in showers through the night. No
real change in airmass with humid conditions keeping overnight
.SHORT TERM /FRIDAY THROUGH SATURDAY/...
Models continue to struggle with the placement and amount of
the heaviest rainfall tonight. Some of the ops models appear to
have convective feedback problems this evening and overnight as
the surface low moves to the east and the trailing upper level
trough swings through. It still looks that the best chance for
heavier rainfall will be confined to the locations near the Mason-
Dixon line this evening and possibly into early Friday morning.
Additionally, convection coverage and strength remains in question
due to all the cloud cover and rain prior to the passage of the
low and aforementioned trough.
The upper level system will exit the forecasting area Friday
morning, decreasing POPs northwest to southeast across the region.
Multiple shortwaves will cross the region Friday night and
Saturday, keeping in shower and thunderstorm chances through the
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
A series of shortwaves moving through the weak trough over the
eastern CONUS will support periodic rain chances and seasonal
temperatures into Monday. A weak bubble of surface high pressure
looks to bring warm temperatures with little chance for showers
Tuesday and Wednesday. A modified Superblend was used for much of
the extended period.
.AVIATION /17Z THURSDAY THROUGH MONDAY/...
A medium confidence forecast with cigs and vis timing generally
following consensus short range model.
Another slug of rain will move through during the afternoon hours
affecting all terminals save for FKL and DUJ where they will
reside far enough north and miss out on MVFR/IFR weather.
Prevailing showers were ended west /21z/ to e /03z/ before IFR
stratus and fog develops late evening. It is still a tough call
on how low vis and cigs drop overnight. For now rolled with IFR at
most airports save for DUJ. Lowest confidence of occurrence is at
FKL since they won`t receive measurable rainfall during the day
light hours. Morning fog and stratus will erode around 14z owing
to VFR weather. Any diurnal showers should pop up after 18z...so
the last six hours of the forecast was kept dry.
The only time window for thunder appears to be in the 21-01z
window as a short wave trough rides northeast along the Ohio
.OUTLOOK /THURSDAY NIGHT THROUGH MONDAY/...
Brief sub VFR restrictions are possible in showers and
thunderstorms through Monday, however given duration and coverage
nothing more than a CB or VCTS/ VCSH expected at this time.