Severe Storm Outlook Narrative (AC)
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ACUS02 KWNS 221650
SPC AC 221649

Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1049 AM CST Sun Jan 22 2017

Valid 231200Z - 241200Z


A few thunderstorms are possible Monday across the Middle Atlantic,
while isolated storms may develop from California into the Four
Corners region.

A strong, amplified belt of westerlies, which has emerged from the
mid-latitude Pacific the past few days, appears likely to be largely
inland of Pacific coast by 12Z Monday.  On the leading edge of this
regime, a significant upper trough is forecast to continue pivoting,
in negatively tilted fashion, east of the mid/southern Atlantic
Seaboard, Monday through Monday night.  An embedded deep, occluded
lower/mid tropospheric cyclone is expected to shift from the lee of
the southern Appalachians through the waters off the Mid Atlantic
coast.  While the associated cold front likely will continue to
advance east of much of the south Atlantic coast, models suggest
that its southwestern flank will stall/weaken over the Gulf of
Mexico, before reforming northward across north central Gulf coastal
areas and the southern Plains by the end of the period.  This latter
development is forecast as surface cyclogenesis takes place to the
lee of the Colorado Rockies, in response to one in a series of short
wave perturbations within larger-scale upper troughing overspreading
much of the western into central United States.  However, a
substantive, deep return flow of moisture from the Gulf of Mexico
will be delayed in the wake of the preceding cold front.

A risk for isolated to widely scattered thunderstorm activity may
linger into Monday, mainly near/beneath the mid-level cold pool
across parts of the Mid Atlantic States.  Areas of scattered
thunderstorm activity also appear possible, mainly on the southern
periphery of the mid-level cold pool overspreading the western U.S.,
from portions of California into the southern Great Basin.  However,
at this time, instability seems unlikely to support an appreciable
risk for severe weather.

..Kerr.. 01/22/2017

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