Area Forecast Discussion
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FXUS61 KPBZ 291146
Area Forecast Discussion
National Weather Service Pittsburgh PA
746 AM EDT Sat Apr 29 2017
Unsettled but warm weather is expected through the weekend.
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Two shortwaves will cross the area today, one this morning and
then a second this afternoon. This will keep in the threat for
showers and storms through much of the day and will also help to
drive the surface warm front to the north, thus destabilizing
the atmosphere as the day progresses. The afternoon shortwave
will ride right along the northward moving boundary and may
provide a real shot at seeing stronger storms during the
With the warm front drifting northward today, there will be a
wide range of temperatures from north to south. The north will
remain in the cooler and less humid air, while the south,
generally south of PIT, will see warm temperatures and rising
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
Warm front will remain near the New York border through Sunday
night as heights rise aloft. This looks to keep a cap on
widespread activity Sunday. With a mid level ridge on Sunday
much warmer and more humid conditions will develop. Ridge begins
to break down Monday as an occluded storm system in the western
Great Lakes pushes a cold front across the region, with showers
and thunderstorms with FROPA.
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
A closed low will eventually move across Southern Canada
Tuesday and Wednesday. The surface reflection will move directly
under the 500 low, keeping the chance for showers in the
forecast. A cooler and unsettled pattern will continue into
late week as a mean mid level trough remains across the ERN
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
-- Changed Discussion --Immediate concern at the beginning of the 12Z TAF period is low
level wind shear, with relatively light surface winds around a
warm front and strong westerly winds aloft. Latest computer
models suggest LLWS should have already come to an end, although
observations including VAD wind profile and upper air balloon
show these winds are still present. With models not much help in
this case, have included LLWS in TAFs other than FKL/DUJ through
15Z, and will reevaluate situation with later observations.
Showers and thunderstorms will continue to move eastward along a
slowly northward moving warm front today. This will mean they
will start the day mainly from KPIT southward, then gradually
transition northward toward KFKL/KDUJ after a gap through much
of the morning. A fairly potent wave should transition down the
front early in the afternoon, which will likely allow for the
best chance of thunderstorms as it passes most sites during this
interlude. As the warm front lifts north of the area Saturday
evening, most sites will scatter out, however some stratus may
linger around KFKL/KDUJ.
Restrictions are possible through Sun in vicinity of a surface
front. Restriction are likely with a strong cold front Sunday
night and Monday.
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