Area Forecast Discussion
Issued by NWS Memphis, TN
FXUS64 KMEG 230536
Area Forecast Discussion
National Weather Service Memphis TN
1136 PM CST Sun Jan 22 2017
Updated for the 06z Aviation Discussion.
.PREV DISCUSSION... /issued 801 PM CST Sun Jan 22 2017/
Updated for POP adjustment and to raise overnight lows.
Based of radar trends precipitation bands will mainly affect the
central and eastern Midsouth counties tonight as the upper low
continues to track across Alabama. So increased pops slightly
along the Mississippi River...and lowered them to the northwest of
Jonesboro and along the lower Tennessee River Valley. In addition
significant cloud cover is keeping temperatures warmer than
forecasted this evening...and this trend will continue till
morning so increase overnight lows a few degrees.
Wind advisory getting into full swing now over the northern Delta
counties...with the strongest gradient moving into the southwest
Delta counties by 04z.
.PREV DISCUSSION... /issued 320 PM CST Sun Jan 22 2017/
At 3PM, Temperatures across the Mid-South are in the mid to upper
50s with overcast skies and light rain. WSR-88D radar trends show
an expansive and nearly stationary area of light to moderate rain
over much of north Mississippi and Eastern Arkansas associated
with a surface boundary and upper level low. Latest water vapor
imagery shows an impressive 540mb upper level low centered over
the ArkLaMiss. To the east of this feature, a large scale severe
weather outbreak is occurring over the Southeast United States.
Within our regime, on the northern periphery of the low, mostly
stratiform rain and cloudy conditions are occurring over the Mid-
South. As the upper level low departs off to our southeast this
evening, a cold front will swing through. The pressure gradient is
expected to intensify with winds reaching advisory criteria
through early Monday morning. As a result, will continue the
advisory through early tomorrow morning.
Short term...tonight through Wednesday...
The greatest chance of rain over the next seven days will occur
tonight and into early Monday morning. Temperatures will drop
into the 40s overnight as drier air advects into the region. All
rain will be east of the area by 6 AM tomorrow morning. Surface
winds will remain moderate throughout the day tomorrow as the
gradient slowly relaxes.
Upper level shortwave ridging will keep conditions dry and
seasonal for Monday and Tuesday. Clouds will hang around for most
of the day on Monday, keeping temperatures in the low to mid 50s
areawide. Temperatures will rebound into the lower 60s on Tuesday
with the aid of returning sunshine.
By Tuesday night, upper level flow will shift southwesterly in
response to an upper level low ejecting from the Intermountain
West. As a result, lee side cyclogenesis is expected to occur. The
surface low will traverse from the Central Plains northeastward
towards the Great Lakes and drag a cold front through the Mid-
South on Wednesday. With limited moisture ahead of the front, a
low chance of rain is currently forecast. Most of the moisture
will likely arrive in the form of clouds during the day, with the
best chance of any rain occurring over portions of northeast
Mississippi. High temperatures will remain in the 50s.
Long term...Thursday through next weekend...
Slightly cooler and more seasonal conditions can be expected for
Thursday through Sunday as upper level flow becomes more zonal and
eventually northwest. Highs will generally be in the 40s with
lows in the lower 30s under mostly sunny skies. Long term model
guidance is consistent in keeping mostly benign and dry weather
through this weekend as moisture remains limited.
MVFR cigs will be common overnight at all TAF sites except KTUP
where IFR cigs will likely develop. There may be a period of VFR
conditions early in the forecast period...but expecting this to
fill back in over the next hour or so. There remains uncertainty
regarding overall cloud cover for the remainder of tonight. Winds
remain strong and gusty from the northwest.
MVFR cigs should persist through Monday at KMKL and KTUP but
should improve to VFR later in the afternoon at both KJBR and
KMEM. Strong and gusty northwest winds will gradually diminish
through the day.
Winds should become light and variable by Monday evening with VFR
cigs developing at all locations by mid evening. There may be some
vsby reductions in fog late in the forecast period in fog.
AR...Wind Advisory until 3 AM CST Monday for Clay-Craighead-
MO...Wind Advisory until 3 AM CST Monday for Dunklin-Pemiscot.
MS...Wind Advisory until 3 AM CST Monday for Coahoma-DeSoto-Marshall-
TN...Wind Advisory until 3 AM CST Monday for Crockett-Dyer-Fayette-