Area Forecast Discussion
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FXUS61 KPBZ 191803
Area Forecast Discussion
National Weather Service Pittsburgh PA
103 PM EST Sun Feb 19 2017
Dry and warm conditions will continue until a frontal system
crosses the region Tuesday night. Well above normal
temperatures are expected through the end of the work week.
.NEAR TERM /THROUGH TONIGHT/...
For the afternoon update stratus looks to hang on across I-70
corridor and south into the afternoon before dissipating.
Adjusted hourly temperatures down where stratus is more
entrenched but still think previous forecast max temperatures
will be reachable. Previous discussion follows.
Adjusted sky grids for stratus closer to satellite and surface
observations for the morning update. Still expect stratus mainly
across the south and ridges to mix out by afternoon with at
least partly sunny skies. Temperatures will remain well above
average with afternoon sunshine.
Clear skies and building high pressure will allow for chilly
temperatures overnight, but still above the seasonal norms.
.SHORT TERM /MONDAY THROUGH TUESDAY/...
Strong ridging builds in the wake of the departing low through
this period, with 500mb heights approaching 576dam by Tuesday
morning. With nearly clear skies and warm advection, expect the
continuation of very warm temperatures through Tuesday, before
a cold front approaches Tuesday afternoon/night.
With such a strong ridge in place over the east, have slowed the
onset of showers from previous forecast.
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
Long term continues to highlight an above-average temperature
trend, as has been suggested by long-range guidance. Despite
the passage of the front Tuesday night, mid-level ridging will
quickly build back over the eastern CONUS as the trough
amplifies over the southwestern US and then ejects into the
central Plains by the end of period.
Looks like a return to more normal temperatures by the weekend.
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
-- Changed Discussion --As of 18Z, MVFR stratus continues to impact KZZV and KMGW, but
stratus should sink south in the next two hours. After that, VFR
conditions will occur at all terminals. Model guidance hints
that there could be additional MVFR restrictions overnight, but
am not convinced that there will be enough low-level moisture.
For now, have generally stuck with a mention of scattered MVFR
clouds, although even if clouds remain scattered, winds may be
light enough to allow fog to develop. Have not put any
restrictions in the forecast yet. West winds around 10 kt this
afternoon will lighten and veer to the northwest overnight.
The next chance for widespread restrictions will be with a
Tuesday cold front.
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