Area Forecast Discussion
Issued by NWS
FXUS61 KPBZ 250042
Area Forecast Discussion
National Weather Service Pittsburgh PA
842 PM EDT Fri Mar 24 2017
Temperatures are expected to be above normal through the seven
day forecast. Rain is expected Sunday into Sunday night, and
again Monday night into Tuesday.
.NEAR TERM /THROUGH SATURDAY/...
HRRR/RAP have backed off the generation of light precipitation
in the I-80 corridor later tonight. Given the lack of upstream
activity and position of boundary well to the north, tend to
think that a dry forecast through 12Z is the way to go. While
some weak isentropic lift overnight will help to generate
lowering and thickening clouds with time, do not see sufficient
forcing to get much in the way of precipitation going. This will
wait until later on Saturday, when a shortwave passing across
southern Ontario and Quebec pushes the frontal zone southward
toward our northern counties. Thus, changes in the near term
were limited to mainly sky and temperature tweaks. Continued
mixing through the night will not allow low temperatures below
the lower and mid 50s, which happen to be the climatologic max
temperatures for this time of year.
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/...
In collaboration with surrounding offices, low temperatures were
reduced a couple of degrees mainly in our eastern counties for
Sunday. The advancing northern boundary may back-door into our
CWA, and with southeast flow setting up from high pressure to
our northeast, a CAD-like pattern suggests that cooler
temperatures may occur along the eastern slopes. Rest of the
forecast for this period unchanged.
While low pressure over the Plains drifts northeastward through
the period, a front will rotate through the region Sunday into
Sunday night. Have continued the categorical pops in the
forecast, along with a chance of thunder Sunday afternoon and
evening. Showers may linger into Monday, primarily across
eastern counties. The frontal passage will do little to change
temperatures, with values remaining well above normal.
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
Weak low pressure will race across the area Monday night into
Tuesday, bringing another round of showers to the area. High
pressure behind the low will yield northerly winds, ushering
in some cooler air. Even so, temperatures should not drop below
seasonal norms. Dry weather is expected Wednesday and Thursday,
with another round of showers forecast for Friday.
.AVIATION /01Z SATURDAY THROUGH WEDNESDAY/...
VFR conditions are expected tonight under shortwave ridging.
Moisture pooling along a slow SWD moving cold front should
result in MVFR ceilings over NW PA by Saturday morning,
continuing through the day. Ceilings should lower elsewhere as
the front moves further south, though VFR levels should be
A low level jet across nrn OH/nw PA should result in a LLWS
potential overnight until the jet diminishes Sat morning.
Restrictions are possible N of PIT Sat night with a warm front.
Widespread restrictions are likely Sunday/Sunday night with
crossing low pressure, and again with a Monday night/Tuesday