Area Forecast Discussion
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FXUS61 KPBZ 201332
Area Forecast Discussion
National Weather Service Pittsburgh PA
832 AM EST Mon Feb 20 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/...
Minor changes to sky cover in the near term, as dense fog
remained locked in across the southern tier of counties. Visible
loops just starting to show the beginnings of burnoff, and the
10 AM expiration time of the dense fog advisory still looks
good. With the slightly slower start to heating, high
temperatures have been reduced slightly across the south, but
values remain above most guidance.
.SHORT TERM /TUESDAY THROUGH WEDNESDAY/...
The latest model runs continue to slow the progression of a
weak front, as it attempts to break down the sharp ridge over
the eastern CONUS. With the slower progression, likely PoPs are
not introduced until later in the afternoon/evening, which
leaves more time for daytime heating in warm advection/mixing.
Thus, highs were bumped up a few degrees despite increasing cloud
cover. The slower passage of the front will leave the chance for
rain in the southern zones through Wednesday morning but this
boundary will do little to change the continued unseasonable
warmth as 850hpa temperatures approach +10C once again.
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
Broad upper ridging will continue to support fast moving waves
and warm temperatures through the end of the week, followed by
a brief return to seasonal values with the passage of a more
amplified shortwave and associated low pressure on Saturday.
Before this system approaches, a weak wave passing north over
the northern Great Lakes may bring a slight cool down and low
chance PoPs on Thursday, before a the warm front with the
intensifying low lifts back over the region.
Strong warm and moist advection in advance of this system will
support values nearly 30 degrees above normal on Friday,
hampered only by any shower activity that occurs. Sharp cold
front will pass Saturday morning, based on consensus of model
guidance. Expect a non-diurnal trend in temperatures through
Saturday, but high pressure building over the region will limit
snow shower activity. Likely PoPs and a chance of thunder were
maintained in the forecast with the Friday night/Saturday front
.AVIATION /14Z MONDAY THROUGH FRIDAY/...
VFR conditions for most airports PIT northward are expected
through the morning under building high pressure. Higher dew
points are in place S of I 70 where cloud cover prevented full
mixing during the day. These areas should see IFR/local LIFR fog
and possible stratus overnight through early Monday morning.
The fog should burn off as mixing begins, with VFR conditions
expected for all locations the rest of the day under the high.
Restrictions are likely with a Tuesday trough and a late Friday
OH...Dense Fog Advisory until 10 AM EST this morning for OHZ039-040-
PA...Dense Fog Advisory until 10 AM EST this morning for PAZ029-031.
WV...Dense Fog Advisory until 10 AM EST this morning for WVZ002>004.