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Area forecast discussion 
National Weather Service Memphis Tennessee
326 PM CDT Sat Jul 12 2014

Discussion...

Tonight into Tuesday...

Very isolated showers and thunderstorms developing across the
forecast area...95 percent of the forecast will see nothing from
these...but as they are developing on radar have added pre-first
period isolated storms to the grids. Hrrr 3km model showed these
starting to develop around 20z...and they did...maybe I should
"listen" to these new hi-res models after all...thought the
dry air aloft with the ridging and the capping seen on the
forecast soundings above 700mb would keep storms from
occurring...but not today as I guess it was overcome with the convective available potential energy
pushing 3.5 to 4.5k j/kg. Precipitation ends shortly after sunset with the
loss of heating and clouds will mostly dissipate with clear to
mostly clear skies.

Models still showing the warmer temperatures for tomorrow with dewpoints
around the lower 70s...pushing apparent temperatures into the 100-104
range...or just below the heat advisory criteria...hottest day of
the year possibly and should be dry. Things begin to change as we
move into Monday...early during the day the deep trough will start
to push south digging into the middle MS valley...pre frontal
trough precipitation possible on Monday...some chances for strong to
severe storms Monday afternoon and evening...all depending on
cloud cover and if atmosphere gets worked over some or not able to
fully destabilize to create very strong storms...something to
watch. Convective available potential energy exceed 2 to 3k j/kg and modest shear...nothing overly
exciting...but possible strong to severe. Deep trough axis pushes
through overnight Monday and drives the cold front into northern
MS by middle afternoon Tuesday...best chances for precipitation exists Monday
night through midday Tuesday for much...if not all of the area.
Decreasing through the afternoon and evening from north to south
and the boundary sags. Not thinking much chance for severe storms
on Tuesday...but some models do show decent cape still in
place...but upper level support is almost none with upper level low
in Quebec.

Wednesday into next weekend...

Models show drying on Wednesday with decent northerly flow pushing
much cooler air into the region...highs near 80 to the lower
80s...nearly 10-15 degrees below normal. Northerly flow continues
into Thursday with cooler than normal and likely dry conditions.
Models diverge some as we approach the weekend...some starting to
show an upper level feature move across the region Friday into
Saturday and creating showers and thunderstorms. Have low probability of precipitation in
as little consistency seen the last two days with how this will
play out with the amplified pattern over the Continental U.S. Breaking
down. GFS ensemble mean shows the region wet Friday and
Saturday and the Euro also this afternoon...and that maybe the likely
trend towards a wet forecast for those days. -Abs

&&

Aviation...

18z taf cycle (12/18z-13/18z)

VFR conditions will occur through the period with the exception
being the possibility of MVFR visibilities in fog at ktup and kmkl
13/08z-13/12z. Winds this afternoon SW 4-7 kts except variable 4 kts at
ktup. Winds tonight S-SW 4 kts or less. Winds Sunday morning SW
4-10 kts.

Jcl

&&

Meg watches/warnings/advisories...
Arkansas...none.
MO...none.
MS...none.
Tennessee...none.
&&

$$

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