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Area Forecast Discussion (AFD)

Issued by Nashville, TN (OHX)

                            
000
FXUS64 KOHX 191654
AFDOHX

Area Forecast Discussion
National Weather Service Nashville TN
1154 AM CDT Wed Jun 19 2019

.UPDATE...
FOR 18Z AVIATION DISCUSSION.

&&

.DISCUSSION...

Only a few minor changes to update the forecast with obs and tweak 
the pop through 12Z tomorrow. Overall, still expecting only a few 
scattered showers and thunderstorms through 18Z across the area. 
Appears to be a boundary setting up to the east of I-65 which has
allowed additional showers and thunderstorms to develop. Scattered showers
have developed along the Tennessee River, so will keep an eye on 
all of these through the afternoon. By 21Z we could begin to see 
the first line of severe thunderstorms moving into our 
northwestern counties. Timing does appear to be somewhat 
problematic with models having a difficult time handling the 
evolving system as a whole. CAMS are hinting at potentially two 
rounds of severe weather, with the first line moving through 
around 21Z and the second line moving in around 01Z. However, the
first line may remain sub-severe, so will need to monitor this
through the afternoon as it develops. The second system appears
that it could be more severe and is expected to progress farther 
southward than the first system. CAPE values should reach over 
2000 J/kg this afternoon, which we already had nearly 1300 J/kg 
from this morning's sounding. Bulk shear should near 35-40 kts 
this afternoon with sfc winds out of the south and southwesterly 
850mb winds. Given all of this, damaging winds does appear to be 
the main threat for tonight's severe weather system. As always, we
can't rule out an isolated hail or tornado event, but the 
environment supports a primarily wind dominated event. 

Besides these edits, the rest of the forecast and temps appear to be 
on track. 

&&

.AVIATION...
18Z TAF DISCUSSION.

Busy Wx pattern to continue...with several wave of showers and storms
expected. Scattered storms will affect much of the east early today,
with a band expected across the area 22z to 03z, then another
bigger round overnight. CIGs and VSBYs will be reduced greatly buy
convection...especially overnight as CIGs may stay MVFR outside
of heavy precip...which won't improve until late Thursday morning. 

&&

.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

DISCUSSION......MacDonald
AVIATION........07