Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Memphis Tennessee
1139 PM CST Friday Dec 6 2013
Previous discussion... /issued 908 PM CST Friday Dec 6 2013/
Discussion...02z surface analysis places a slow moving Arctic
cold front from the Carolinas back through southern Mississippi
and Alabama. Meanwhile...a 1043 mb ridge of Arctic high pressure
was centered over South Dakota and Nebraska this evening. Knqa/kgwx
WSR-88D radar trends indicate precipitation has ended across the
middle south. Klzk WSR-88D radar trends show a few returns near
Batesville Mississippi but not likely that anything is reaching
Latest 00z upper air sounding from klzk indicates a building
subsidence inversion with moisture limited from the surface to 760
mb. Thus...not favorable for ice nuclei activation associated with
deeper moisture. A few flurries are possible but overall
coverage/confidence remains too low to justify mention in the forecast.
Will make adjustments to the remainder of tonight/S forecast to
remove precipitation chances...adjust sky cover to include partial
clearing across portions of the middle south...especially across
east/northeast Arkansas...the Missouri bootheel and portions of
far northwest Tennessee. The current Wind Chill Advisory area
looks good at this time but will continue to monitor
temperature/wind trends over the next few hours if a possible
expansion is necessary.
Updated forecast grids will be available shortly.
Previous discussion... /issued 543 PM CST Friday Dec 6 2013/
Winter storm continues to affect the midsouth at this time...
Precipitation continues to stream northeastward over the midsouth.
Temperatures range from the middle 20s across northeast Arkansas to the
upper 30s across northeast Mississippi. Snow is occurring north of a
Jonesboro to Paris Tennessee line. From Memphis to
Jackson...freezing rain is occurring with occasional sleet mixing in
at times. Between these two corridors...there may be some pockets of
just sleet occurring. The freezing line has pushed southward to a
line roughly located Clarksdale to near Corinth.
Models continue to indicate much of the precipitation will pull out
of here around 6 PM for most of the County Warning Area. Some lingering rain or
freezing rain may occur across northeast Mississippi depending on
what the temperatures are. There could also be some patchy freezing
drizzle occurring for a couple of hours this evening. Will let
evening shift decide if an advisory is warranted after the winter
storm warnings end. Strong northerly winds will continue to usher in
colder air this evening into the overnight hours. Lows will range
from around 10 degrees across Randolph County Arkansas to near 32
degrees in Monroe County Mississippi. The combination of the cold
temperatures and strong winds will produce wind chill values below
zero across northeast Arkansas and the Missouri bootheel late
tonight into Saturday morning. Will issue a Wind Chill Advisory.
Saturday will be chilly. High clouds will stream over the area.
Right now will continue with partly sunny conditions but would not
be surprised if the cirrus is thick enough to make it mostly cloudy.
In addition...additional clouds ahead of the next system will begin
to spread into north Mississippi...east central Arkansas...and
southwest Tennessee during the afternoon hours. Thus cloud cover and
strong northerly winds will keep highs from around 20 degrees in
northeast Arkansas to the upper 30s across northeast Mississippi.
Another surface low will develop along the Gulf Coast Saturday night
through Monday as a shortwave swings across the area. This will put
the midsouth in an overrunning pattern again. With cold air in
place...freezing rain and sleet will occur over areas along and west
of the Mississippi River while eastern areas will see freezing rain
change to rain or just rain occur as some warmer air filters into
the area. Best chances for precipitation will occur over northeast
Mississippi where just rain is expected. In locations that receive
freezing rain or sleet...amounts could range from around a tenth of
an inch up to a quarter of an inch.
Another low will develop by Monday night and again bring
precipitation back northward into mainly just northeast Mississippi.
Colder air will have filtered into the area by this time thus
precipitation may fall more as sleet/snow but only minor
accumulations are expected at this time.
Thereafter...below normal temperatures will continue over much of
the week as cold Arctic high pressure settles over the region.
The high begins to shift east Thursday into Thursday night.
Temperatures will begin to return to normal. Although another
shortwave will bring precipitation into the area on Friday. However
this time it will just be rain.
06z taf cycle
Rapidly changing conditions can be expected at all sites over the
next 24 hours as one storm system moves out of the area and the
next one quickly approaches. Most sites...tup possibly being the
exception will see brief clearing tonight or tomorrow before high
clouds overspread the area...eventually lowering again tomorrow
afternoon. Showers will likely approach mem...jbr and mkl before
06z...and most likely be a prevailing element at tup by 03z. Will
go with vcsh at the 3 northern sites before 06z. Winds will
remain northeast 10-15 kts at all sites.
Preliminary point temps/pops...
mem 19 29 27 34 / 20 10 80 80
mkl 18 29 27 35 / 30 10 80 80
jbr 12 21 19 29 / 10 10 60 50
tup 26 36 34 42 / 40 20 80 90
Arkansas...Wind Chill Advisory until noon CST Saturday for Clay-Craighead-
MO...Wind Chill Advisory until noon CST Saturday for Dunklin-Pemiscot.