Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Memphis Tennessee
1126 PM CST Wednesday Dec 24 2014
updated to add 06z aviation discussion.
Previous discussion... /issued 928 PM CST Wednesday Dec 24 2014/
midlevel clouds had begun to break up since earlier this
evening... while the backedge of the clouds was approaching
central Arkansas from the west. Temperatures in the clearing over eastern OK
had cooled to around 10 degrees colder than over central Arkansas.
With dewpoints in the middle and upper 30s over the midsouth...temperatures
should to near currently forecast values in the lower and middle
30s...with patchy fog and frost possible where skies clear during
the predawn hours.
Previous discussion... /issued 537 PM CST Wednesday Dec 24 2014/
updated to add 00z aviation discussion.
Previous discussion... /issued 333 PM CST Wednesday Dec 24 2014/
Final vorticity lobe associated with exiting system is moving across
the midsouth this afternoon. Some very light returns showing up on
radar in eastern Arkansas...it is doubtful that these will produce
more than isolated sprinkles as they come across. Cloud cover
should gradually decrease from west to east overnight tonight.
Christmas day and night will see flat ridging over the area with
warmer temperatures and much less cloud cover than the past
several days. Surface ridging will move off to the east resulting
in winds coming around to southerly. Upper ridging should hold
through much of Friday before heights start to fall ahead of next
Expect moisture to increase ahead of approaching system Friday...
with probability of precipitation increasing from west to east Friday night. Saturday and
Saturday night should see the most widespread rain...with precipitation
slowly diminishing Sunday night/Monday.
Next week...a system will affect the midsouth in the
Tuesday/Wednesday time frame. This system will tap into some
Arctic air and drop temperatures considerably by midweek. Given
the uncertainty regarding specifics of this system at this long
range...chose to go with conservative probability of precipitation at this time.
However...forecast temperatures suggest some winter precipitation
will be possible. We will continue to monitor trends in the
06z taf cycle
Clearing skies are expected tonight at all sites over the next 2-4
hours. Sufficient low level moisture may result in the
development of patchy fog and subsequent MVFR/IFR visibilities at
mkl/tup between 25/09-12z. Otherwise...VFR conditions expected to
prevail through much of the period. West/northwest winds will
become light overnight...increase to southwest winds between 7-11
kts at mem/mkl/tup and between 12-14kts with gusts to 22kts at
jbr...then back south and decrease to 4-7 kts after 26/00z.