Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Pittsburgh PA
858 PM EDT Monday Apr 27 2015
after showers diminish this evening...dry and warmer weather is
expected for Tuesday and Wednesday.
Near term /through Tuesday/...
shower activity now confined to a few straggling isolated showers
north and east of Pittsburgh as the axis of the upper trough swings
through. Showers that blossomed during the afternoon hours have
dwindled as the sun has set...and as heights build from the west.
Any remaining showers should cease to exist by midnight.
As the trough swings south tonight/early Tuesday...deeper moisture
currently generating light rain in upstate New York will also move
through. As mentioned above...heights have been building quickly
through the late evening as high pressure pushes in. Associated
subsidence will result in squashing the rain upon arrival...but
the clouds are expected to linger. Although temperatures will push
close to the freezing mark in some locations...the expected cloud
cover should keep large temperature drops at Bay.
Still think that clouds will linger into a good part of
Tuesday...rejuvenating into a cumulus field by surface heating. This
combined with light northerly winds will prevent any major
warmups. However...late April sun angle should still manage to
bring temperatures to within a few ticks of the 60 degree mark.
Short term /Tuesday night through Thursday/...
conditions should remain quiet Tuesday night and Wednesday before
the region falls under a Pincher attack. A cold front will approach
from the northwest...while a low is expected to move up the Atlantic
Seaboard Wednesday night through Friday. Computer models have been
all over the place with these systems over the last few days. As a
result...have made little change to this portion of the forecast.
However...it does appear that more moisture will be available with
the coastal front than with the front...so have gone with a gradient
from east to west across the forecast area for rain chances on
Long term /Thursday night through Monday/...
chance probability of precipitation diminishing west to east Thursday night as system
moves off the middle Atlantic coast. By Friday and through the
weekend...model discrepancies on handling upper level low over
East Coast make for a low confidence forecast...and continued to
follow newest wpc forecasts into Monday.
Aviation /01z Tuesday through Saturday/...
high MVFR/low VFR ceilings will persist through the night. Fkl/duj may
see lower MVFR ceilings and some fog late tonight in northwest flow.
Expecting scattered-broken cumulus development starting late morning
Tuesday...with VFR conditions maintained. Gusty winds will
diminish over the next couple of hours...but continue to blow at
5-10 knots through Tuesday. Cl
Outlook.../Tuesday through Saturday/...
the next chance for general restrictions is expected with
Thursday low pressure.