Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
333 AM EST Thu Dec 18 2014
Valid 12Z Thu Dec 18 2014 - 12Z Sat Dec 20 2014
...Chance for flash flooding and severe storms from the Western Gulf coast
to the Lower Mississippi Valley...
...Heavy rain and higher elevation snows expected in the Northwest...
...Rain and snow will clear out over northern New England...
The wintry mix of precipitation across the Central Plains and Middle
Mississippi Valley will begin to diminish while moving northeastward into
the Ohio and Tennessee Valleys on Thursday; However...energy swinging out
of northern Mexico will help ignite a new area of precipitation to the
north of a frontal boundary stretched over the Western Gulf Coast late
Thursday. Abundant moisture from the Gulf will fuel heavy rains with
embedded thunderstorms across South Texas early Friday...which should lift
into the Lower Mississippi Valley by Friday afternoon. Areas of flash
flooding and severe weather will both be a possibility within developing
After a day of widely scattered shower activity...a strong Pacific system
approaching the coast will bring more significant precipitation into the
western U.S.. Heavy rains and higher elevation snows will begin impacting
the Pacific Northwest by late Thursday...and precipitation will spread
southeastward over Northern California...Intermountain West...and Northern
Rockies as the system moves inland over the Western U.S. on Friday.
Rain and snow wrapping inland over northern New England should come to an
end on Thursday as a deep surface cyclone lifts out towards the Canadian
Maritimes. Light snow showers downwind of the Lower Great Lakes could
linger into Friday...but an expansive surface high sliding eastward from
the Upper Midwest will keep locations from the Northern Plains to the
Northeast dry and quiet heading into the weekend.
Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php