Scientific Forecaster Discussion
fxus64 kmeg 181126 aaa
Area forecast discussion...updated
National Weather Service Memphis Tennessee
626 am CDT Wed Sep 18 2019
updated for 12z aviation forecast discussion below.
Previous discussion... /issued 459 am CDT Wed Sep 18 2019/
Discussion...GOES-16 satellite trends place Hurricane Humberto
near Bermuda, tropical depression Imelda near Houston, an upper
level trough along the West Coast of the United States, and a
upper level ridge axis entrenched across portions of the
central/Southern Plains and the middle/lower Mississippi valleys.
As of 4 am CDT, mainly clear skies are prevailing across the mid-
south with temperatures predominantly in the upper 60s to lower
70s across most locations.
Mainly rain free conditions are expected across the mid-south
today as an upper level ridge will remain in place across the
region. Short term convective allowing model (cam) solutions hint
at perhaps a isolated shower and/or thunderstorms perhaps south
of I-40 in east Arkansas and northwest Mississippi west of I-55
coincident with peak afternoon heating by late this afternoon.
However, confidence remains too low to justify mentionable rain
chances at this time. Another day of hot record breaking heat is
expected across the forecast area with temperatures once again
reaching the middle/upper 90s to approaching 100 degrees along and
west of the Mississippi River including northeast Mississippi.
Short term model trends indicate the remnants of tropical
depression Imelda should drift into northwest Louisiana/southwest
Arkansas Thursday into Friday. This will bring a potential of
isolated to perhaps scattered showers and thunderstorms mainly
west of the Mississippi on Friday. Otherwise, mainly rain free and
dry conditions are expected to persist across most of the mid-
south into Saturday with slightly cooler temperatures due to an
increase in cloud cover.
Long term models continue to struggle with the upper level ridge
breaking down over the lower Mississippi Valley late this upcoming
weekend into next week. The operational GFS continues to remain
the aggressive outlier compared to the preferred Canadian and
European model (ecmwf) solutions. Thus, i've kept the forecast slightly warmer and
drier with rain chances mostly in the isolated range for now until
models come into better agreement with overall pattern.
Nonetheless, a look at the upper level pattern towards the middle
to latter half of next week would suggest a transition to
northwest flow aloft and perhaps a better potential for showers
and thunderstorms and slightly cooler but above normal
Climate records for 9/18/19:
mem 97 2010
mkl 98 1953
jbr 99 1931
tup 97 1953/1936/1933
VFR and light northeast winds will prevail today under persistent