Area Forecast Discussion
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FXUS61 KPBZ 220124
Area Forecast Discussion
National Weather Service Pittsburgh PA
924 PM EDT SAT MAY 21 2016
A wet weekend will give way to a drier beginning to the new week.
Warmer conditions will also follow for much of the upcoming week.
.NEAR TERM /THROUGH SUNDAY/...
-- Changed Discussion --Bulk of showers now north and east of pittsburgh as mid level
trough begins to close off over central pennsylvania. Adjusted
pops to account for this trend, although patchy light showers
will also remain across rest of region. Lowered min temps a
couple degrees mainly across the north based on current and
upstream readings. Previous discussion follows.
Upper trough only slowly shifting east this evening as another
shortwave dives down backside of trough early tonight across the
eastern lakes. Have slowed eastward progression of likely pops
this evening and maintained chance pops back into eastern ohio
until after midnight. No changes to temperatures as they look in
A secondary surge of mid-level cold air will move into the CWA
for Sunday. This will allow for more unstable lapse rates yet
again. Model soundings do indicate 500-900 J/kg of CAPE and given
that the majority of it is in the thermal charge separation layer,
a slight chance of thunderstorms was added to the forecast for
Sunday. However, Sunday certainly does not look like at all the
washout that Saturday has been. Sunday max temps not as cool as
saturday but still 5 to 10 degrees below seasonal averages.
-- End Changed Discussion --
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
Remaining diurnal rain showers over the east will taper off Sunday
night after the atmosphere becomes more stable. The slow moving
vertically-stacked low pressure system will linger along the Mid-
Atlantic through Monday. Meanwhile, a ridge will continue to build
west of the area and will try to suppress cloud and rain
production. Enough moisture and instability associated with the
low remains over our eastern 1/3 Monday afternoon for showers with
isolated thunder. This activity will once again diminish with the
Tuesday should remain dry as the low slowly meanders up the coast
and the ridge crawls in. Sunshine and increasing southwesterly
flow will lead to climbing temperatures through midweek.
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
Ridging building across the eastern United States will result in
southwesterly flow, tapping moisture from the Gulf of Mexico.
Compared to previous model runs, Wednesday appears to be mostly
dry, but otherwise there should be a fair chance for showers
through the rest of the week. Kept thunder mention during
afternoon/evening hours following a diurnal cycle. Temperatures
will be above normal through the period.
.AVIATION /01Z SUNDAY THROUGH THURSDAY/...
A deepening upper trough and low level moisture should keep
mainly MVFR and patchy IFR conditions across area ports overnight.
Mixing should gradually increase conditions to VFR for much of the
area by early Sunday afternoon, though areas closer to the upper
low toward east of PIT should remain mainly MVFR.
Shower coverage should continue to diminish tonight, before re-
developing on Sunday as the trough deepens into a cut off low
across PA. Enough instability could exist Sunday afternoon for a
few thunderstorms, but left mention out of TAFs at this time due
.OUTLOOK /SUNDAY NIGHT THROUGH THURSDAY/...
Restrictions are possible through Monday before the upper low