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Area forecast discussion 
National Weather Service Memphis Tennessee
1135 PM CST Tuesday Mar 3 2015


Updated aviation discussion for 06z tafs below...


Previous discussion... /issued 959 PM CST Tuesday Mar 3 2015/

locally dense fog over north MS and east Arkansas had expanded east of
the MS river at midevening. Dense fog advisory has been expanded
into west Tennessee where visibilities will likely fall to near advisory
levels through late evening.

Quick look at the newly arrived 00z GFS showed little change from
the 18z run. The midsouth is still on track for a significant
winter storm on Wednesday. Have tweaked the grids slightly to
include/extend freezing rain and ice accumulation over north MS
Wednesday evening and early morning Thursday...based on 18z GFS
soundings and in line with neighboring forecast offices.


Previous discussion... /issued 343 PM CST Tuesday Mar 3 2015/

fairly significant timing changes this afternoon with respect to
the upcoming winter storm. In a nutshell things look to have
slowed down a bit meaning rain will last longer...before the
cangeover to freezing rain...sleet and snow. Additionally sleet
and snow accumulations have increased...especially in the
Missouri bootheel and northern portions of western Tennessee.

As the result of fog early in the day and extensive cloud
cover...high temperatures did not quite make their mark today.
Middle afternoon temperatures range from the middle 40s in
northeast Arkansas to the low 60s in eastern portions of north
Mississippi. Southerly winds have been slower than expected to
respond to a a developing low in the plains...but we are finally
beginning to see speeds in the 10kt range. Deep moisture from
southern Mississippi has moved into much of the midsouth...south
of Interstate 40 with dew points in the middle to upper 50s across
much of north Mississippi. Upper level dynamic support will
approach the region overnight enhancing lift. As a result
precipitation should increase in both coverage and intensity. A
few thunderstorms are possible...but do not look as likely as they
did 24 hours or so ago.

Temperatures this afternoon will be the warmest we see for quite
sometime...possibly for a week or longer. Temperatures will
likely remain fairly steady for much of the night...maybe cooling
a bit toward morning...but the real cooldown will take place
tomorrow. Freezing temperatures should arrive in northeast
Arkansas middle morning...northern portions of west Tennessee around
noon...and across the remainder of the midsouth except eastern
portions of north Mississippi. Far eastern portions of north
Mississippi may not reach freezing until just before midnight.
However...keep in mind that sleet and snow can fall with
temperatures well above warm as 37 degrees in some don't rely on the freezing line to determine when
show/sleet may begin. Freezing rain still looks to be a lesser
threat...maybe as high as one quarter of an inch in east central
Arkansas into southwest Tennessee...but the more significant
threat will come from accumulating sleet. Sleet can accumulate at
temperatures well above freezing...even warmer than snow. Up to 6
inches of sleet may accumulate in northern portions of west
Tennessee and the Missouri bootheel. With much of west Tennessee
and east Arkansas seeing 2-4 inches of accumulation. Temperatures
will continue to cool overnight with morning lows ranging from the
middle teens to middle 20s. Latest guidance keeps wintry
precipitation around well into the day Thursday...especially in
north Mississippi. Watches/warnings may need to be extended even
further in time. Temperatures Thursday are not expected to climb
above freezing...and if significant sleet/snow in on the ground as
expected...making it into the upper 20s might be optimistic. Any
snow/sleet accumulation will linger.

Frigid conditions will continue Friday and Saturday. Highs Friday
may climb above freezing...but once again...if significant
sleet/snow accumulations linger climbing out of the middle 30s might
be a struggle. Morning lows Friday will range from the low single
digits to middle teens. Hopefully we will all see above freezing
temperatures Saturday...but morning lows will be in the teens
across most of the area.

Sunday into Monday temperatures will trend warmer...but remain
below normal. Near normal temperatures may return by
significant precipitation is expected Saturday through midweek.



06z taf set

Thinking has not changed much from 00z concerning Wednesday.
However...mem has scattered out significantly recently but do not
trust this trend to last. Expect ceilings to fill back in and stay
IFR/LIFR after 08z through the taf valid period. Fog has also
developed area-wide and has been dense at times. 1/4sm is not out
of the question intermittently overnight.

Timing and precipitation type is the main challenge tomorrow. The front
will sag south through the middle-south during the day with freezing
rain...sleet...and snow all possible. The changeover will occur
earliest at northern terminals and latest at tup. Winds will also
become very gusty between 00 and 06z Thursday.



Meg watches/warnings/advisories...
Arkansas...dense fog advisory until 6 am CST Wednesday for Clay-Craighead-
Crittenden-cross-Greene-Lawrence-Lee Arkansas-Mississippi-
Phillips-Poinsett-Randolph-St. Francis.

Winter Storm Warning from 6 am Wednesday to noon CST Thursday
for Clay-Craighead-cross-Greene-Lawrence-Mississippi-

Winter Storm Warning from noon Wednesday to noon CST Thursday
for Crittenden-Lee AR-Phillips-St. Francis.

MO...dense fog advisory until 6 am CST Wednesday for Dunklin-Pemiscot.

Winter Storm Warning from 6 am Wednesday to noon CST Thursday
for Dunklin-Pemiscot.

Flash Flood Watch through Wednesday morning for Dunklin-Pemiscot.

MS...dense fog advisory until 6 am CST Wednesday for Benton MS-

Winter Storm Warning from noon Wednesday to noon CST Thursday
for Alcorn-Benton MS-Coahoma-DeSoto-Marshall-Panola-Quitman-

Winter Storm Watch from Wednesday evening through Thursday
morning for Calhoun-Chickasaw-Itawamba-Lafayette-Lee MS-

Tennessee...dense fog advisory until 6 am CST Wednesday for Crockett-Dyer-

Winter Storm Warning from 6 am Wednesday to noon CST Thursday
for Crockett-Dyer-Gibson-Henry-Lake-Lauderdale-Obion-

Winter Storm Warning from noon Wednesday to noon CST Thursday
for Benton Tennessee-Carroll-Chester-Decatur-Fayette-Hardeman-

Flash Flood Watch through Wednesday morning for Benton Tennessee-



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