Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
400 AM EDT Sun May 20 2018
Valid 12Z Sun May 20 2018 - 12Z Tue May 22 2018
...Heavy rain possible over parts of Southern Florida...
...Heavy rain possible over parts of the Lower Rio Grande Valley...
A quasi-stationary front extending from the Northeast to the Ohio Valley
westward to the Middle Mississippi Valley then southwestward to the
Southern Plains will have the southwestern portion of the boundary
dissipate by Monday evening. The far eastern part of the front will
slowly sink southward to the Mid-Atlantic while a new western half of the
boundary develops from the Middle Mississippi Valley westward to the
Central High Plains by Monday evening into Tuesday. Rain and
thunderstorms developing along the eastern end of the boundary will move
off the Northeast and most of the Northern Mid-Atlantic Coast overnight
Sunday. Showers and thunderstorms will also develop along and near the
front from parts of the Ohio Valley westward to the Middle Mississippi
Valley and from the Middle Mississippi Valley southwestward to the
Southern Plains through Monday evening.
Meanwhile, upper-level energy over parts of Central Northern Florida into
the Southeast Coast will slowly drift northwestward into parts of the
Tennessee Valley by Monday evening. The system will produce showers and
thunderstorms from the Southern Mid-Atlantic Coast to Florida Peninsula
that will expand westward into the Southeast and the Tennessee Valley by
Sunday evening. The showers and thunderstorms will continue from the
Central Gulf Coast/Tennessee Valley eastward to the Southern Mid-Atlantic
Coast/Southeast through Monday evening.
Furthermore, a deepening upper-level trough over the West Coast will
deepen while an upper-level low develops over South-Central California by
early Monday morning then settles over parts of Southern California into
the Great Basin by Monday evening. The energy will aid in developing rain
and embedded thunderstorms over parts of the Pacific Northwest into parts
of the Great Basin on Sunday morning that will develop into an area of
showers and thunderstorms extending from parts of the interior Pacific
Northwest/Northern California into Northern/Central Rockies and Great
Basin that will have a diurnal component through Monday evening.
Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php