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Area forecast discussion 
National Weather Service Memphis Tennessee
625 am CDT Sat may 23 2015

updated to add 12z aviation discussion.


Previous discussion... /issued 314 am CDT Sat may 23 2015/


The upper ridge of high pressure over the southern U.S. And middle
south will hold on for one more day and keep mainly dry conditions
in place. Temperatures will be on the rise as well with highs
reaching into the upper 70s north to middle 80s south. Dry
conditions should continue tonight with mild overnight lows mainly
in the 60s.

The upper ridge will break down on Sunday as an upper level low
pressure system over the southwest U.S. Begins to lift towards the
northeast. Southwesterly flow aloft along with low level southerly
flow will advect abundant deep tropical moisture northward into
the area from the eastern tropical Pacific and western Gulf of
Mexico. A series of upper level shortwaves will traverse the
region in the flow aloft resulting in numerous to widespread
showers and thunderstorms by early next week.

Chances for showers and thunderstorms will increase beginning
Sunday afternoon and evening as the first in a series of
shortwaves lifts northeast from the arklatex into the middle
Mississippi Valley. The atmosphere in advance of this shortwave
should become moderately unstable with cape values ranging from
1000-1500 j/kg. In addition...deep layer shear on the order of 35
to 40 kts should overspread the western half of the region. This
may support a few strong storms with gusty winds Sunday afternoon
and evening...mainly along and west of the Mississippi River. In precipitable water values approach 2 inches and
dewpoints rise to near 70 degrees...the threat for heavy rainfall
with any storms will increase. Temperatures will remain warm on
Sunday with most locations reaching into the lower and middle 80s.

Wet weather will continue the first half of next week as a series
of shortwaves move through the region and interact with the
tropical airmass that will be in place. Numerous to widespread
showers and thunderstorms can be expected for Monday through
Tuesday night. Heavy rainfall will be possible and may lead to an
enhanced threat for flash flooding across the region. A flash
flood/Flood Watch may become necessary for the first part of next
week. This threat will continue to be monitored through the
weekend. Temperatures should be held down by the enhanced storm
coverage and cloud cover...although humidity levels will remain

The upper trough will finally begin to shift northeast with
showers and thunderstorms still likely Wednesday over the eastern
half of the area...with more scattered coverage further west. The
upper level pattern will become less amplified by the end of next
week. The tropical airmass will remain in place and combined with
daytime heating will lead to a more typical diurnal convective
pattern with greatest storm coverage during the afternoon and
evening hours...diminishing overnight. Temperatures should warm a
few degrees over early week readings with a return to normal late
may conditions.

Another upper level low pressure system and associated upper
troughing will approach the middle south late next week into next
weekend. This will again increase storm chances during this time
period along with continued seasonably warm and humid conditions.



12z taf cycle

VFR conditions expected to continue through the period. Vcsh
possible at mem/jbr after 24/09z. NE/east winds will veer southeast today
and increase to between 7-11 kts.



Meg watches/warnings/advisories...


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