Area Forecast Discussion
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FXUS61 KPBZ 180534

Area Forecast Discussion
National Weather Service Pittsburgh PA
1234 AM EST Mon Dec 18 2017

Warmer, but damp weather can be expected through Tuesday.


The late eve update featured further adjustments to POPs as the
rain area has diminished with ewd progress of the supporting
shortwave. The chance for measurable precip will continue to
diminish and temperature is expected to remain above freezing
for all areas. Given expected temperature/dewpoint spreads,
have delayed, and restricted the drizzle mention to areas in
vicinity of the stalled frontal boundary, i.e. areas north of

An early eve update was issued to adjust hourly trends of
temperature and precipitation based on the radar, obs, and
consensus short guidance.

Light rain associated with a weakening upper level shortwave
will spread across the region through this evening. For the most
part, temperatures remain above freezing, with marginal
readings along the I 80 corridor where minimal precip is
anticipated. No headline is thus anticipated.

Cloud cover and light precip chances will support very little
diurnal temperature change for tonight and Monday.


Zonal flow is maintained, though weak ripples in the upper level
pattern may be enough to generate additional light precip. Have
cut back PoPs significantly since forcing remains weak and much
of the moisture remains under about 2kft.

Strengthening warm advection Tuesday ahead of a slightly more
amplified wave will support above average temperature with
values closer to normal in cold advection/northwest flow.
Building surface ridge should lend to little more than cloud
cover wednesday.


Zonal flow returns Thursday with some amplification in the upper
level pattern as wave ejects into the Plains. This will be the
next notable system progged to approach late in the period, with
some differences between the guidance in timing. Stayed close
to the Superblend for the end of the week with some moderation
in warm advection to above average temperature by the end of the


Restrictions are anticipated into Monday as light rain and
drizzle will prevail under an inversion trapped over the
region. Expect IFR with low stratus by Monday morning in
vicinity of the frontal boundary draped near the I 80 corridor.
Little to no improvement is expected through Tuesday morning as
the moist airmass stagnates.

South-southwesterly winds will remain at 10kts or less through
the forecast period.

Restrictions are likely through Tuesday, as abundant low-level
moisture remains trapped under the inversion.




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