Area Forecast Discussion
Issued by NWS Memphis, TN

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS64 KMEG 211730
AFDMEG

Area Forecast Discussion
National Weather Service Memphis TN
1230 PM CDT Sat Oct 21 2017

.UPDATE...

Updated for the 18z Aviation Discussion.

&&

.PREV DISCUSSION... /issued 913 AM CDT Sat Oct 21 2017/

UPDATE...
Updated for morning showers and cloud cover.

DISCUSSION...

Radar trends show WAA showers are slowly diminishing in coverage
since sunrise...however some real estate east of the Mississippi
River could see a couple of hundredths of an inch before noon.
Have expanded the slight chance for a shower accordingly and
increased cloud cover in the east where broken skies will
continue.

JAB

&&

PREV DISCUSSION... /issued 438 AM CDT Sat Oct 21 2017/

Another mild day for the Midsouth today, accompanied by increased
humidity and wind speeds, ahead of an approaching upper level
trof.

The upper trof will make only slow eastward progress today,
before additional energy arrives from the central Rockies tonight.
This additional energy will drop into the base of the trof and
become cut-off from the northern branch segment over the upper
Midwest Sunday afternoon. The newly-formed positively-tilted cut-
off low and associated elevated warm conveyor belt will make only
slow eastward progress on Sunday. Hourly rain rates shouldn`t be
particularly high, but the rainfall persistence could lead to some
storm total rainfall of 2 to 3.5 inches east of the MS River by
Monday afternoon.

The upper low should exit the region late Monday, replaced by a
deep longwave trof over the eastern half of the US through
midweek. As deep longwave trofs go, this one will not be very
persistent, lifting out to the Atlantic on Thursday and allowing
the upper pattern to quickly deamplify over the lower 48. Under
fast zonal flow, low level warm advection will result in
moderating mid/late week temps and dewpoints over the Midsouth.
The milder temps will be short-lived, as steep upper height falls
and associated surface cold frontal passage sweep through on Friday.
Numerous showers should accompany the front, along with a few
thunderstorms, mainly south of I-40.

PWB

&&

.AVIATION.../18z TAFs/

VFR conditions should continue through the remainder of this
afternoon and into late evening. Cigs and vsbys will gradually
lower to MVFR later tonight into Sunday morning from west to east.
Rainfall along with a few thunderstorms are also anticipated
during the last 6-8 hours of the forecast period.

Southerly winds will continue to increase early in the period and
remain elevated through the remainder of the forecast. Gusts are
anticipated later tonight into Sunday morning.

JLH

&&

.MEG WATCHES/WARNINGS/ADVISORIES...
AR...None.
MO...None.
MS...None.
TN...None.
&&

$$



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.