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FXUS64 KMEG 221138

Area Forecast Discussion
National Weather Service Memphis TN
538 AM CST Fri Nov 22 2019

Updated to include 12Z Aviation Discussion.

.PREV DISCUSSION... /issued 422 AM CST Fri Nov 22 2019/ 


The latest surface analysis places a cold front from Cleveland, OH
back through Dyersburg, TN and back through Little Rock, AR. A 
surface low was analyzed along the front near the ArkLaTex at this
hour. Temperatures north of the front are in the lower 50s with 
low to mid 60s south of the front. The latest KNQA radar scan 
shows moderate showers along and north of the front, with an area 
of thunderstorms moving along I-40 in eastern Arkansas.

Widespread showers and thunderstorms are expected through late
morning across much of the Mid-South as the cold front slowly sags
southward. The front is expected to stall over north Mississippi
by this afternoon, with a lull in shower activity expected across
much of the area. The aforementioned surface low, currently over 
ArkLaTex, will lift through the area this afternoon and into this
evening. This will bring another round of showers and 
thunderstorms to the area through the overnight hours.

The main upper level low over the Four Corners is expected to 
eject quickly across the Lower Mississippi Valley overnight and 
help push the front south of the Mid-South by early Saturday 
morning. A few post-frontal showers will be possible through late
Saturday morning, mainly along the Tennessee River. Behind this 
system, the westerlies will remain progressive. 

Surface high pressure will build in briefly for Sunday and Monday,
before a quick moving system arrives Tuesday night. Temperatures
will moderate some during this period, with upper 50s to lower 
60s expected on Monday and Tuesday. 

A stout shortwave will cross the Rockies early Tuesday and eject 
across the Central Plains during the morning hours. At the 
surface, a maturing low pressure system is expected to form near 
Oklahoma and lift northeast towards Saint Louis during the 
afternoon hours. This will allow a modified warm sector to move 
into north Mississippi, and maybe as far north as west Tennessee, 
Tuesday night. A quick-moving cold front is then expected to swing
through Tuesday night and into early Wednesday morning. Luckily, the
best dynamics will actually reside to our north, negating the 
potential for any severe weather. About half an inch is expected
with the quick-moving system.  

Behind the front, dry conditions will briefly return as the 
subtropical ridge builds in on Wednesday. Thanksgiving is still a
bit of a toss-up at the moment, as models are struggling with
resolving shortwaves rotating around the ridge. Either way, the
pattern looks to remain wet and unsettled in the extended period.  



12Z TAFs

Lower ceilings due to low stratus will remain a challenge in this
TAF set as the atmosphere will remain saturated along a
weakening and nearly stationary boundary across the Lower
Mississippi Valley. This is expected to result in mainly IFR
conditions today and potentially deteriorating to LIFR conditions
by tonight. The first round of rain with perhaps an embedded 
elevated thunderstorm will depart this morning. There may be a 
break in activity later this morning into early afternoon before a
second round of rain with perhaps an elevated thunderstorm moves 
through the region later this afternoon into tonight. The best 
potential for VCTS will be at TUP and confidence is too low to 
include in other TAF sites at this time. NNE winds between 6-11 
kts anticipated at sites except at TUP where S winds are expected 
to become ESE winds between 5-7 kts this afternoon.



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