Area Forecast Discussion
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FXUS61 KPBZ 271245
Area Forecast Discussion
National Weather Service Pittsburgh PA
745 AM EST Mon Feb 27 2017
Rain chances return today with a crossing warm front. A series
of disturbances will keep periodic rain in the forecast through
mid week until the passage of a cold front returns wintry
weather for the last half of the week.
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Mid and high clouds have essentially overspread the entirety of
the CWA this morning. RUC/RAP/HRRR soundings indicate a fairly
dry layer generally below 5 kft still resides over the southern
flank of the area even as radar mosaics indicate precipitation
is starting to spread from south to north into the CWA. This dry
air will likely take a few hours to overcome, during which time
temperatures with warm advection should continue to rise above
freezing. Thus, most all areas will start off as and remain all
rain when precipitation spreads northeastward through the
afternoon as warm advection continues.
Under weak warm advection through the day, temperatures should
steadily increase, however owing to virtually no chance of
sunshine, highs will not really take off. That said, as 850 mb
temperatures rise to around 0C by the afternoon, temperatures
should rise into and through the 40s at most spots. Fries
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/...
Precip chances should end this evening as the shortwave exits
and the warm front lifts N of the area. The region is progged to
be in the warm sector in SW flow ahead of a trough advancing ewd
from the Western CONUS. Several shortwaves and increasing low
level jet support are progged to cross the area with periodic
showers expected Tuesday and Tuesday night. There is a chance of
thunderstorms Tuesday night with elevated instability and
The western trough is progged to approach the Great Lakes region
Wednesday as an associated surface low tracks from the Midwest
into Southern Ontario. Increasing speed and directional shear
is progged through the day as the low`s associated cold front
approaches. 500mb winds approaching 100kt on both NAM and GFS
model soundings is indicative of the strong jet progged over
the area. Severe thunderstorms are possible if enough
instability develops during the day. This will be monitored over
the next couple of days, but a mention will be included in the
hazardous weather outlook.
Broad upper troughing is expected over the area Wednesday night
and Thursday, along with eventual lake and terrain enhancement
in cold advection. This should keep snow showers chances in the
forecast. Temperatures are expected to be 20 to 25 degrees above
average Tue and Wed, returning to near or below seasonal levels
.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
Broad upper troughing is expected to continue through late
week, with a reinforcing crossing shortwave/surface low with
some snow Thursday night and Friday. General zonal flow is
progged by the weekend as the trough exits, with mainly dry
conditions and moderating temperatures.
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
VFR can be expected through daybreak although mid level
cloudiness is increasing as a shortwave trough approaches. That
disturbance is forecast to generate some light rain and snow at
ZZV and MGW this morning, with light showers lingering along a
northward-developing warm front through the day.
MVFR cloudiness under the crossing shortwave has been limited
to ports south of PIT given low level moisture expectations with
the better chance of precip, but have also introduced cloud-
restrictions for FKL and DUJ during the eve given front-
Restrictions are likely Tuesday as precip develops with another
shortwave in strengthening wsw flow. More restrictions and wind
problems can be expected with, and in the wake of a Wednesday