River Flood Warning 7, NWS Pittsburgh, PA

Area Forecast Discussion
National Weather Service Pittsburgh PA
930 PM EST Thu Feb 7 2019

.SYNOPSIS...
A crossing cold front will end the rain over the region early
on Friday. A brief period of cool and dry weather will follow
until active weather returns Sunday into next week.

&&

.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
No further changes were needed for the eve update as rain
continues in advance of a cold front, with associated low
pressure digging over the Great Lakes.

Previous...
A late aftn update was issued to adjust wind gusts and precip.
probs. based on the latest radar, obs., and consensus short
model input.

Flood watch remains in effect, but fast movement of the system
and supporting elements should limit that threat and keep any
issues from being too widespread.

&&

.SHORT TERM /6 AM FRIDAY MORNING THROUGH SATURDAY NIGHT/...
A rapid end to the precipitation shield is expected Friday
morning with the passage of the sfc cold front. Most of the
precipitation will be out of the area before its cold enough to
change to snow, but areas north of I-80 and along the eastern
ridge line could see this change over. Little to no
accumulation is expected.

Along and behind the front will be a significant increase in sfc
winds out of the WNW that will gradually taper off through Friday
afternoon. The increased mixing during this period will allow
for gusts up to 35kts, but should remain below advisory level
as the mixing won't reach the strongest winds located at the
800mb level.

The rest of Friday into Saturday will be characterized by dry
weather, decreasing cloud cover, and below normal temperatures.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
A series of disturbances will cross the region beginning Sunday
and into the next work week. Due to residual cold temperatures,
the first will primarily bring snow to the region, though the
lack of deep moisture should keep accumulations light. The
ensuing disturbances will come with warmer temperatures and thus
more rainfall.

&&

.AVIATION /03Z FRIDAY THROUGH TUESDAY/...
While visibilities were expected to drop with both the warm
front and cold front passages, there was only a brief drop in
visibilities with heavier showers along the warm front, and
upstream obs show no reductions in visibility with the cold
front. So all TAFs were amended to remove visibility
restrictions, as well as raise ceilings in between the fronts as
nearly all sites are also reporting VFR ceilings.

A fine line on the Wilmington Ohio radar indicates the location
of the cold front, and coincident with the frontal passage are
winds gusting to 35-40 kt and ceilings dropping back to 1-2kft.
Have also amended all TAFs with updated timing of when the cold
front should move through and bring restrictions. Rain should
continue briefly with the frontal passage itself, then quickly
come to an end.

Maintained LLWS through the evening hours at all TAF sites with
a strong low- level jet ahead of the cold front.

MVFR ceilings will linger, with improvement back to VFR
possible by midday Friday.

.Outlook...
A disturbance moving off the Great Lakes is forecast to bring
the next general-restriction chance late Sunday.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...None.
OH...Flood Watch until 7 AM EST Friday for OHZ039>041-048>050-
     057>059-068-069.
PA...Flood Watch until 7 AM EST Friday for PAZ007>009-013>016-
     020>023-029-031-073.
WV...Flood Watch until 7 AM EST Friday for WVZ001>004-012-021-509.

&&