Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Memphis Tennessee
350 PM CDT sun Mar 16 2014
Discussion...20z surface analysis this afternoon places a
surface low over north Central/Northeast Mississippi.
Precipitation thus far today has been located mainly along and
north of I-40 for much of the day. Temperatures as of 3 PM CDT
range from the middle to upper 30s near the Tennessee/Kentucky
border...40s along the I-40 corridor...and upper 50s to around 70
degrees across north Mississippi with the warmest readings
occurring along and southeast of Tupelo. Precipitation trends
into tonight along with windy conditions are the main challenges
in this afternoon/S forecast.
A surface low over north Central/Northeast Mississippi will
continue to move east into northern Alabama and Georgia tonight.
Latest regional metar observations/WSR-88D radar trends indicate
precipitation is mostly in the form of rain across the lower
Mississippi Valley this afternoon. Further west...the nearest
wintry precipitation in the form of snow is occurring across
portions of southwest Missouri and northwest Arkansas late this
afternoon in a deformation zone on the back side of the low.
This deformation zone will gradually shift east across the middle
south this evening with precipitation gradually anticipated to
become lighter as the night progresses. Based on the latest trends
feel models may be overdoing the amount of expected quantitative precipitation forecast on the
back side of this low and have trended amounts on the light side.
Short term model soundings indicate some of the precipitation may
begin to transition to a rain/sleet/snow mixture this evening
north of a line from Wynne to Huntingdon Tennessee. At this
time...think any light accumulations at best will be mainly on
grassy surfaces as soil temperatures across west Tennessee still
remain warm today. Thus...will hold off on a Winter Weather
Advisory for now. Evening shift will continue to monitor short
term trends and adjust forecast if necessary. Any lingering
precipitation is anticipated to come to an end towards Monday
In addition to the precipitation chances tonight...a tight pressure
gradient mainly located along and west of the Mississippi River
has produced Wind Advisory conditions...especially across
northeast Arkansas this afternoon. Metar observations have
indicated weakening winds late this afternoon further west across
Arkansas. As the evening progresses winds will gradually weaken
and the Wind Advisory may be able to be cancelled earlier than 1
Models indicate a ridge of high pressure will build in across the
middle south for Monday into Tuesday. Highs on Monday will struggle
to reach the 50s with a gradual moderation of temperatures into
the 60s by Tuesday. Long term GFS/European model (ecmwf) long term models continue
to struggle with the handling of a middle week cold front across the
lower Mississippi Valley. The GFS remains on the quicker side of
solutions and has less moisture than the European model (ecmwf) solution.
Consequently...have kept forecast trended towards a precipitation
free solution for the time being until models come into better
agreement. Long term models indicate another front will move
across the region Friday into Saturday bringing another chance of
precipitation and perhaps some overrunning precipitation towards
the end of the long term forecast.
A surface low will track near or just south of mem and near or just
north of tup this evening into the overnight hours. Winds will be
strong and gusty at all sites and shift swiftly from the northeast
as the low passes. Expect gusts as high as 35 kts this afternoon
gradually diminishing overnight. Scaled back precipitation to
mostly vcsh as opposed to rain on station. Ceilings will remain IFR to
MVFR through the period. Visible will be highly variable...as low as 1sm
in association with the heavier showers...but MVFR conds should
prevail. Only marginal improvement is expected before 18z tomorrow.
Preliminary point temps/pops...
mem 31 51 37 65 / 50 10 0 0
mkl 31 50 33 64 / 50 10 0 0
jbr 26 49 33 64 / 50 10 0 0
tup 36 52 35 66 / 40 20 0 0
Arkansas...Wind Advisory until 1 am CDT Monday for Clay-Craighead-
MO...Wind Advisory until 1 am CDT Monday for Dunklin-Pemiscot.
MS...Wind Advisory until 1 am CDT Monday for Coahoma-DeSoto-Tunica.
Tennessee...Wind Advisory until 1 am CDT Monday for Dyer-Lake-Lauderdale-