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Marine and Coastal Impacts from Imelda; Unsettled Weather in the West

Swells and high surf from both Imelda and Humberto are expected to bring dangerous marine conditions and rip currents to much of the East Coast over the next several days. A series of Pacific frontal systems will bring waves of showers and thunderstorms to portions of northern California and the Pacific Northwest through midweek. Read More >

 

Historic Flooding Across The Tennessee Valley

February 22-23, 2019

 

Radar loop of composite reflectivity 

from early morning through mid afternoon (click to enlarge)

 

A persistent wet pattern in early/mid February setup poor antecedent conditions later in the month.  

Subtropical ridging over the western Atlantic combined with troughing out west to set the

stage for epic flooding across the Tennessee Valley as moisture continued to stream into the

region.  Already wet ground wasn't able to absorb much (if any) additional rainfall, thus vast

amounts of runoff occurred.  This led to increasing River and Areal flooding conditions, which

culminated on Saturday February 23rd, 2019.  Daily rainfall records were shattered at McGhee

Tyson Airport.  Below are some interesting graphics.

 

Radar loop of one hour estimated rainfall

from early morning through mid afternoon (click to enlarge)

 

Observed and Estimated Rainfall Totals (30 Hour, 48 Hour, 72 Hour, 1 Week) (click to enlarge)

 

500 MB Heights (green contours), MSLP (dashed black contours),

and Surface front analysis, QPF (click to enlarge)

 

300 MB Winds (image and black contours) and

200MB - 400MB Upper Divergence (black shading) (click to enlarge)

 

Surface front analysis, Precipitable Water (image and black contours),

and Moisture Transport Vectors (click to enlarge)