Area Forecast Discussion
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FXUS61 KPBZ 281607
Area Forecast Discussion
National Weather Service Pittsburgh PA
1207 PM EDT Fri Apr 28 2017
Mild under high pressure this afternoon, with unsettled but
warm weather expected for the weekend.
.NEAR TERM /THROUGH SATURDAY/...
Low dew points with seasonably warm temperatures will continue
under high pressure through the afternoon.
Tonight a frontal boundary will return north as a warm front,
with showers and thunderstorms developing, especially later
tonight as a shortwave races east along the front. POPs look to
increase after midnight with best mid level support along the
boundary. Most models push the warm front north toward the New
York and Pennsylvania border where it stalls late day Saturday.
Have trended forecast in this direction, but confidence is not
exceptionally high. SPC has maintained a marginal risk of
severe, but with better dynamics well west of region through
Saturday, for now think severe threat not high enough to
Rising dew points will help keep temperatures mild tonight,
with warming behind the front Saturday.
.SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY NIGHT/...
Warm front should remain near the New York border through the
period as heights rise aloft. This looks to keep a cap on
thunderstorms through the period, with warm and more humid
conditions developing under the ridge aloft.
.LONG TERM /MONDAY THROUGH THURSDAY/...
Eastern ridge begins to break down on Monday, as deep upper
level system spins northward from the plains/Midwest on Sunday,
toward the Great Lakes by Monday night. The 500 low will
eventually move across Southern Canada Tuesday and Wednesday.
The surface reflection will move directly under the 500 low and
swing the occluded front through the Upper Ohio Valley late
Monday/Monday night. This will increase the risk for showers and
storms. A cooler and unsettled pattern will continue into late
week as a mean mid level trough remains across the ERN CONUS.
.AVIATION /16Z FRIDAY THROUGH TUESDAY/...
VFR conditions are expected for this afternoon under high
pressure, with high clouds and light winds becoming more
southerly with time.
Moisture increases after 00Z as a warm front lifts back north.
Clouds will lower with time, with MVFR ceilings showing up
northwest of PIT by sunrise. Showers and a few thunderstorms
are expected as well, with thunder chances too low to include
yet, but brief IFR visibilities are possible late tonight.
Occasional restrictions are possible this weekend along a
stalled frontal boundary. Better restriction chances arrive
with a strong cold front Sunday night into Monday.