Quantitative Precipitation Forecast Discussion
NWS Weather Prediction Center College Park MD
300 PM EDT Sun Mar 11 2018


Prelim Day 1 QPF Discussion
Valid Mar 12/0000 UTC thru Mar 13/0000 UTC
Reference AWIPS Graphics under...Precip Accum - 24hr


Day 1...

...Lower Ohio Valley - Tennessee Valley - Southern-Central
Appalachians - Mid Atlantic - Southeast...

The well-defined shortwave over the mid MS Valley will pivot
across the TN Valley and eventually off the southeast coast.
Meanwhile, the northern stream wave -- dropping south of
Hudson/St. James Bay early this afternoon -- will drop across the
Great Lakes and Ohio Valley toward the end of the period (00Z
Tue). These features will become more in phase by Monday, and in
doing so, lend support to a southern "Miller-B" cyclone evolution
as the surface low across the TN Valley weakens with time upon
crossing the mountains and gives way to cyclogenesis off the mid
Atlantic coast. 

The latest WPC reflected noteworthy changes with the 12Z guidance
from the previous model cycle(s) -- particularly a boost in
amounts across central SC-NC where the model consensus depicts a
widening area of coupled southern stream/northern stream dynamical
forcing. At the same time, have curtailed amounts a little north
of the VA/NC border during day 1, in light of the upper shortwave
ridge/lower level anticyclonic flow lingering a while longer.

Hurley