Scientific Forecaster Discussion
Area forecast discussion...updated
National Weather Service Pittsburgh PA
934 PM EDT Monday Jul 27 2015
warm and humid weather will continue across the region until a
cold front passes on Wednesday night.
Near term /until 6 am Tuesday morning/...
930pm update...another quiet and warm night. Activity over the far
southern ridges has almost dissipated and cloud cover continues to
dwindle. Have updated temperatures with latest guidance.
Benign weather will continue today and overnight across the vast
majority of the forecast area with the only chance of an isolated
thunderstorm or two mainly limited to the higher terrain of
Tucker and Garrett counties where the combination a weak boundary
orographic lift may provide enough lift through early evening.
With weak surface winds...minimal change to dewpoints currently
in the low to middle 60's across the region...and clear skies overnight
allowing for maximum radiational cooling...patchy fog is expected to
develop overnight as temperatures fall.
Short term /6 am Tuesday morning through Thursday/...
ridging will build over the region through Wednesday...and with
height and temperature anomalies around 1-2 Standard deviations
above normal...forecast maximum temperatures are anticipated to be
around 5 to 10 degrees above normal across the region. This
combined with projected dewpoints will result in apparent
temperatures reaching the middle 90s Tuesday and Wednesday. A
cold front will then cross the region Wednesday evening through
Thursday morning...bringing a chance of showers and storms along
with with a little relief in apparent temperatures behind the
Long term /Thursday night through Monday/...
surface ridging is prognosticated to build in under a weak...broad
eastern Continental U.S. Upper trough. This should keep mainly dry and
seasonally warm weather through much of the period. The trough is
prognosticated to deepen early next week returning rain chances to the
region. Followed close to ensemble based wpc gridded
guidance...smoothing out some operational model differences over
Aviation /02z Tuesday through Saturday/...
VFR conditions are
anticipated at all of the taf sites through this evening. While
some scattered showers and thunderstorms may be possible south of
the PA/WV border...did not feel confident enough in the coverage
or northern extent to add prevailing shra/tsra.
Some MVFR/IFR fog is possible once again overnight...especially
toward the stationary boundary where better low level moisture
will be present. Lamp guidance backed off of IFR for all ports so
MVFR was made the prevailing visibility restriction from pit
VFR conditions should return Tuesday.
Outlook...Tuesday through Saturday...
restrictions are possible with a late Wednesday/early Thursday