Scientific Forecaster Discussion
fxus61 kpbz 192239
Area forecast discussion
National Weather Service Pittsburgh PA
639 PM EDT Sat Oct 19 2019
the remnant of Nestor will dig across the Carolinas tonight with
light rain limited to areas southeast of Pittsburgh. Dry and warmer
weather will start the new week.
Near term /through Sunday/...
high clouds will continue to spread over the upr Ohio tonight, and will
lower over areas southeast of Pittsburgh as shortwave ridge gives way
to the remnant of tropical storm Nestor, which will dig rapidly
across the Carolinas toward the coast. Any associated rain will
remain light and will only affect areas along and east of a Latrobe-
Warm advection and the increase in clouds with the advance of that
system will hold temperature about 5 degrees above the average.
Short term /Sunday night through Monday/...
a building shortwave ridge in the wake of that system will support
dry weather for Sunday with temperatures remaining approximately 5
degrees above the calculated-normals.
On Monday, a deepening upper low is projected to dig toward the upr
MS valley with strong southerly flow developing over the upr Ohio. The
resulting warm advection will drive temperature above the 70 f mark
for the majority of the cwa, despite an increase in clouds. The first
showers ahead of the approaching front may arrive in our southeast
Ohio counties prior to sunset.
Long term /Monday night through Saturday/...
the front will sweep across the region later Monday night and
Tuesday morning. A robust rain band should accompany the front, with
lift supported by the approaching shortwave trough as well as
layered frontogenesis. Around a half inch of rain still appears
likely for the area. Rain should come to a relatively quick end
behind the front, as west-southwest flow is pictured behind the boundary, as
opposed to the period of northwest flow behind the system earlier this
week. Temperatures will drop back towards climatology for Tuesday
night and Wednesday. Dry weather will then persist through Thursday,
with a warming trend thanks to return flow from departing high
The models still diverge on the pattern thereafter. The European model (ecmwf) is
more progressive in pushing the next shortwave into the region by
Friday night, while the GFS keeps the trough over the Mississippi
Valley through then, pushing it east on Saturday. Will rely on model-
blended pops for now, keeping values in the 30-40 range.
Aviation /22z Saturday through Thursday/...
high pressure will maintain VFR through Sunday.
restrictions are likely Monday night into Tuesday with a frontal
approach, subsequent passage, and coincident rain.