Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Memphis Tennessee
904 PM CST Sat Nov 22 2014
Skies are partly to mostly cloudy over much of the forecast area
this evening with temperatures ranging from around 50 degrees to
the lower 60s. There were a few showers over portions of northeast
Arkansas this afternoon but this activity moved out of the
forecast area by sunset. A large area of showers and isolated
thunderstorms is moving out of northeast Texas and into southwest
Arkansas and northwest Louisiana. This activity will reach the
forecast area sometime after midnight. Will update forecast to
remove evening wording with few changes needed.
Previous discussion... /issued 520 PM CST Sat Nov 22 2014/
showers continue to lift off to the north. By 5 PM...showers
should be out of the County Warning Area and the County Warning Area should remain dry through at
least midnight. After midnight...a potent upper trough will begin
lifting out of Texas. Low clouds will quickly spread into midsouth
after midnight. A few showers may push into portions of northwest
Mississippi near Clarksdale and east central Arkansas near
Helena-West Helena shortly before sunrise. The bulk of the shower
activity will spread into the midsouth after sunrise on Sunday.
Expect Sunday to be cloudy and rainy much of the day. As a
result...models continue to back off on instability ahead of the
negatively tilted trough. Can/T rule out scattered embedded
thunderstorms developing within the showers but chances of any
strong to severe storms are looking less likely now than a couple
of days ago.
The upper trough will lift northeastward by 00z (6 pm) Sunday
evening cutting off chances for showers and thunderstorms.
However...the cold front will begin to push into the midsouth
during the evening which may produce a few additional showers
along or ahead of the front. Front should exit the midsouth by
Monday morning. High pressure will build into the area behind the
front. Temperatures will return to the upper 40s to upper 50s for
Models seem to be backing off on the cold air for Thanksgiving.
Now both the 12z GFS and 12z European model (ecmwf) show a cold front moving into
the midsouth during the afternoon hours on Thanksgiving and
stalling the front over north Mississippi for the Holiday weekend.
This would keep the Arctic air to the north but could bring rain
chances into the area Friday night into Saturday. For now have
left the forecast as is to make sure models continue with this
trend. Have bumped highs up slightly for Wednesday and
00z taf cycle
VFR conds expected for much of the night in advance of an
approaching system. Winds east to southeast 5-10kt. Ceilings will
lower early tomorrow to MVFR and eventually IFR at all terminals
as low pressure tracks toward the region and a front approaches
from the southwest. May be some elevated thunderstorms as well so
added a mention of thunderstorms in the vicinity after 23/12z or so. Rain looks likely at
all sites for much of the day tomorrow.