U.S. Severe Weather Forecast (Convective Outlook)

Day Three

acus01 kwns 280059 
Storm Prediction Center ac 280058 

Day 1 convective outlook 
National Weather Service Storm Prediction Center Norman OK 
0758 PM CDT Mon Mar 27 2017 

Valid 280100z - 281200z 

..there is a slight risk of severe thunderstorms across portions of 
southern Tennessee and into adjacent northeast Mississippi and 
northern Alabama... 

..there is a marginal risk of severe thunderstorms from the 
middle-Ohio Valley southwest across the Tennessee Valley to the 
Mississippi Delta Region... 

Scattered severe thunderstorms will continue for the next few hours 
(i.E. A good portion of the evening) -- centered over the Tennessee 
Valley area. Hail and damaging winds will be the primary severe 

..mid-Ohio Valley south-southwest to the Mississippi Delta area... 
Numerous showers and thunderstorms continue across the region -- 
though a gradual decrease in intensity continues early this evening 
as a combination of diurnal effects and widespread convective 
overturning is resulting in a generally stabilizing environment 
across much of the area. 

Greatest severe risk appears likely to linger over parts of southern 
middle Tennessee and into northeast Mississippi and northern 
Alabama, in conjunction with a fairly well-organized band of storms 
currently crossing middle Tennessee (just southeast of the upper low 
which is now centered in the vicinity of western kentucky). With 
500 to 1000 j/kg mixed-layer cape ahead of this convective band in 
conjunction with enhanced westerly flow aloft on the south side of 
the upper system, stronger cells will likely maintain potential to 
produce hail in excess of severe levels and locally damaging winds 
-- possibly into the late evening hours before diminishing. 

.Goss.. 03/28/2017 


Mesoscale Discussion

acus11 kwns 272300 
sels mesoscale discussion 
Storm Prediction Center mesoscale discussion 272259 

Mesoscale discussion 0349 
National Weather Service Storm Prediction Center Norman OK 
0559 PM CDT Mon Mar 27 2017 

Areas affected...parts of western/middle Tennessee and adjacent 

Concerning...Severe Thunderstorm Watch 89...91... 

Valid 272259z - 280030z 

The severe weather threat for Severe Thunderstorm Watch 89, 91 

Summary...the risk mainly for severe hail and strong surface gusts 
is expected to continue with storms overspreading middle Tennessee 
into/through the 7-10 PM CDT time frame. 

Discussion...in the wake of generally weakening, loosely organized 
convective development now spreading toward the central/southern 
Appalachians, an area of enhanced low-level warm advection is 
maintaining vigorous thunderstorm activity near/east of the 
Interstate 40 corridor of western into middle Tennessee. Forcing 
associated with the remnants of a compact mid-level closed low 
likely is augmenting ascent and associated convection, which is 
expected to continue to spread eastward across middle Tennessee 
into/through the 00-03z time frame. 

Inflow of relatively moist low-level air into the vicinity of this 
activity, beneath a lingering area of steep mid-level lapse rates is 
probably contributing to moderately large cape. This may be mostly 
based above a relatively stable surface-based air mass, but, in the 
presence of strong vertical shear, supercells will remain possible, 
with upscale growth into a small organizing convective system 
possible through mid/late evening. While an additional isolated 
tornado may not be out of the question, the risk for severe hail and 
strong surface gusts seems more prominent. 

.Kerr.. 03/27/2017 

..please see www.Spc.NOAA.Gov for graphic product... 


Latitude...Lon 36648735 36848646 36658534 35898499 34978634 34768747 
34928859 35138904 35948841 36648735