Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
400 AM EDT Mon May 21 2018

Valid 12Z Mon May 21 2018 - 12Z Wed May 23 2018

...there is a slight risk of severe thunderstorms over parts of the Ohio
Valley...

...Heavy rain possible over parts of the Southwest/Eastern Gulf Coast...

A front extending from the Mid-Atlantic westward to low pressure over the
Ohio Valley/Middle Mississippi Valley then southward across parts of the
Lower Mississippi Valley into the Southern Plains will have the southern
half of the boundary dissipate by Monday evening.  Overnight Monday, a new
boundary develops over parts of the Central Plains into the Ohio
Valley/Middle Mississippi Valley.  The surface low will slowly move
northeastward to the Northern Appalachians by Tuesday evening pulling the
associated front to portions of the Mid-Atlantic across the Southern Ohio
Valley.  Showers and thunderstorms will develop along and near the
boundary from parts of the Mid-Atlantic to the Middle Mississippi Valley
and southward across parts of the Lower Mississippi Valley into the
Southern Plains will slowly lift northeastward to the Northeast on Tuesday
into Tuesday evening while showers and thunderstorms continue over parts
of the Ohio Valley into the Lower Mississippi Valley.  In addition,
upper-level energy over the Southeast will become quasi-stationary over
parts of the Eastern Gulf Coast through Tuesday evening as additional
upper-level energy moves northward along the Southeast Coast.  The energy
will aid in producing showers and thunderstorms over parts of Florida into
parts of the Eastern Gulf Coast that will expand westward into the
Tennessee Valley and northward into the Southern Mid-Atlantic through
Tuesday evening into Wednesday. 

Meanwhile, a deep upper-level trough over the West Coast will slowly move
into parts of the Great Basin while weakening by Tuesday evening. 
Upper-level dynamics and moisture moving northwestward out of the Western
Gulf of Mexico will aid in developing showers and thunderstorms over parts
of the Southern High Plains into the Southern Rockies through Tuesday
evening.  


Ziegenfelder


Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php