Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Pittsburgh PA
201 am EST Tuesday Jan 27 2015
light snow showers and flurries will remain today before high
pressure decreases clouds tonight.
Near term /through today/...
area of snow light snow in weakening deformation zone continues
across the ridges. Elsewhere only flurries and have cancelled
northern part of advisory. Still some lower visibility in snow in the
southern ridges and a fluffy inch or two still possible into the
late morning hours. Otherwise shortwave diving from the western
Great Lakes into the upper trough over the northeast U.S. Will
keep clouds and light snow showers across the region through the
day with temperatures only recovering into the 20s.
Short term /tonight through Thursday/...
frigid high pressure tonight into Wednesday with lows in the
single digits to near zero over northern counties. Readings were adjusted
for the latest deterministic trends and collaboration.
Fast moving low pressure is projected off the Great Lakes on Thursday.
Next fast moving shortwave looks to bring a mixed bag of precipitation
Long term /Thursday night through Monday/...
main concern for the early part of the long term will be the speed
in which the upper level trough/clipper crosses the region. The most
recent run of the GFS seems to be the fastest...so opted to stay
closer to a blend of the European model (ecmwf) and previous runs. This would keep
precipitation into the early part of Friday with northwest flow and snow showers
lingering into Friday afternoon. Beyond this time period the model
solutions diverge a bit more at the surface...making it hard to put
anything more than chance probability of precipitation in the forecast. Will maintain an
overall cooling trend in temperatures as a broad trough remains
overhead through Tuesday...which is close to wpc forecast values.
Aviation /07z Tuesday through Saturday/...
appears a general MVFR forecast is in order through the period.
Large stratocu deck will continue to rotate over the region on
back side of coastal low. Eastern ports could see a redevelopment of
snow showers later this morning and into the afternoon as
shortwave...swinging in from the west...will interact with
Outlook.../Tuesday through Friday/...
the next chance for widespread restrictions is expected on
Thursday and Friday with crossing low pressure.
Maryland...Winter Weather Advisory until 7 am EST this morning for mdz001.
PA...Winter Weather Advisory until 7 am EST this morning for paz074-
WV...Winter Weather Advisory until 7 am EST this morning for wvz023-