Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Pittsburgh PA
857 am EDT Wednesday Jun 3 2015
stalled upper level system will finally begin to drift eastward
today and head off the Carolina coast Friday morning. A weak cold
front will cross the area Friday night.
Near term /until 6 PM this evening/...
855 am...updated sky cover to current trends. Also raised
afternoon high temperature slightly in response to lamp numbers. Rest of
forecast looks good...still expect rain showers chances across the far
southern County Warning Area.
Clouds will be the forecast challenge today. Any showers that
develop...would be confined to the far southern tier of my area
as upper level support will be weak and mainly situated over
Temperatures will again be below normal.
Short term /6 PM this evening through Friday/...
closed upper low is still expected to cross the Tennessee Valley
and slowly trudge eastward...before weakening and crossing the
Carolina coast Friday morning.
Still expect most rain shower activity tonight to lie south and
east of pit...especially close to the ridges...as easterly flow
keeps most moisture locked up there. This is also the area that
will be more subject to midlevel ripples rotating around the upper
low. Did reduce probability of precipitation on Wednesday and continued to keep thunder
out of the forecast...as the transition to a more southerly flow
component looks delayed as compared to yesterday.
On Thursday and Friday...BUFKIT profiles show a more favorable
environment for diurnal convection areawide as return flow sets up
on back of departing surface high to our north. Given the lack of
a coherent trigger...will keep probability of precipitation in the scattered/chance
category west of the ridges. Weak upsloping will continue in the
higher elevations...with a damming look to the low level wind/temperature
Fewer clouds and the return of southerly flow will point to a
warming trend...with above normal temperatures expected by the end
of the week.
Long term /Friday night through Tuesday/...
model and ensemble guidance continue to favor the passage of a
cold front Friday night...which should finally bring a drier
period with ample sunshine behind it. However...the improved
conditions will likely be short-lived as the consensus favors
cyclonic flow re-establishing itself over the County Warning Area by early next
week...meaning a southerly drop of the jet axis and a better
chance the storm track would favor wet conditions again by early
Aviation /13z Wednesday through Sunday/...
mainly MVFR stratus ceilings are through middle morning for most
ports south of I 80 as an inverted surface trough sets up across
the region. Far northern ports should stay VFR with dry low level
air in place. The stratus should eventually mix out into a diurnal
cumulus layer by late morning/early afternoon with VFR ceilings
Outlook.../Thursday through Sunday/...
periodic restrictions are possible through Saturday under
persistent troughing with daily shower/storm chances.