Mesoscale Discussion 0014
NWS Storm Prediction Center Norman OK
0320 AM CST Mon Jan 08 2018
Areas affected...Portions of northeastern Alabama...northwestern
Georgia...and eastern Tennessee
Valid 080920Z - 081415Z
SUMMARY...Generally light freezing rain, perhaps briefly mixed with
sleet, will develop east from Alabama into Tennessee and Georgia
this morning. Freezing rain rates of a few hundredths of an inch per
hour will be possible during the morning commute.
DISCUSSION...The regional WSR-88D mosaic depicts a rather expansive
area of precipitation across parts of the Southeast early this
morning, although reflectivity is inflated in spots due to bright
banding. Regardless, as mid-level warm advection and related
isentropic ascent spread east ahead of a trough nearing the lower
Mississippi Valley, precipitation will gradually spread across the
remainder of northeast Alabama and adjacent portions of Tennessee
and Georgia through sunrise.
Recent Huntsville, AL (KHTX) correlation coefficient data indicate
some descent of the melting layer near/along the leading edge of
this precipitation shield, which would suggest a brief/spotty
potential for ice pellets. This notion is also suggested by the
initially dry profile from the surface through approximately 700 mb
(as depicted by the observed 06Z FFC/Peachtree City, GA sounding).
However, continued warming/moistening atop a shallow sub-freezing
surface layer will likely support light freezing rain as the
dominant precipitation type this morning. In turn, rates up to a few
hundredths of an inch per hour will be possible through the morning
...Please see www.spc.noaa.gov for graphic product...
LAT...LON 35088438 33988446 33908451 33648486 33538512 33448556
33518597 33948616 34258628 34588642 35138643 35518627
35718610 35978585 36268549 36378515 36268478 36098459