Area Forecast Discussion
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FXUS61 KPBZ 242141
Area Forecast Discussion
National Weather Service Pittsburgh PA
541 PM EDT Wed Aug 24 2016
A couple of crossing disturbances will return rain chances to the
Upper Ohio Valley Region tonight and Thursday.
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
Ridging should move east of the area this evening as a shortwave
approaches from the Midwest. Increasing clouds and shower chances
are expected tonight with the approach and passage of the wave. A
few thunderstorms are also possible west of PIT this evening where
sufficient diurnally driven instability is progged before waning
later tonight. Lows are expected to be around 10 degrees above
.SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY/...
Expect a decrease in precip chance Thursday morning as the first
shortwave exits, though chances should increase again through the
day with the approach of a front. The northern zones are progged
to be in a favorable environment to experience more numerous
convection Thursday as the front sags southward. Fueled by day
time surface heating and increased flow aloft, some thunderstorms
may reach severe criteria, but overall coverage and intensity
should be marginal across the region as instability remains
limited by very warm mid level temperatures.
Precipitation chances are projected to wane on Friday as surface
high pressure builds in the wake of a weak front. Given the
strength of the upper ridge, southward frontal penetration is
questionable, but will generally persist with a dry forecast through
Saturday as per the latest deterministic trends as flow becomes
zonal. Warm weather will continue as zonal flow across the northern
ridge periphery shunts warm air across the region.
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
Flow is expected to back to a southwesterly direction as an upper
high enhances and shifts towards the Mid-Atlantic. As a result of
the strengthening ridge, anonymously high surface temperatures
and upper heights are predicted by ensemble models and have led
to higher confidence in raising forecast temps early in the
period. Overall, hot and humid conditions can be expected in the
beginning of the long term until the passage of a shortwave on
Monday provides some relief from the heat. POPs were maintained in
association of the aforementioned shortwave as per the latest
.AVIATION /22Z WEDNESDAY THROUGH MONDAY/...
Few Cirrus across the region this evening, otherwise expect mid
clouds to increase later tonight as a shortwave approaches. Showers
will encroach from the west overnight, but coverage may be limited
due to lack of low level instability. Only mentions of VCSH
overnight, with a better chance of restrictions Thursday as main
.OUTLOOK /THURSDAY THROUGH MONDAY/...
Periodic restriction chances should persist through Friday with
the approach and passage of a cold front.