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Area forecast discussion 
National Weather Service Memphis Tennessee
637 am CDT Friday Aug 29 2014

Discussion...

Updated for the 12z aviation discussion

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Previous discussion... /issued 407 am CDT Friday Aug 29 2014/

Discussion...
the radar across the midsouth is quiet at 3 am. Temperatures are
in the low to middle 70s with the exception of the Memphis metropolitan
area where temperatures remain in the upper 70s. We will likely
see two to three more degrees of cooling before sunrise resulting
in morning lows ranging from the upper 60s to middle 70.

It looks like we are transitioning into a much wetter patter for
the last couple of days of August into early September. The ridge
and surface high pressure that has kept US hot and dry for the
past couple of weeks will shift along the East Coast and a highly
amplified longwave trough will shift across the Mississippi River
valley...though it will Delaware-amplify significantly as it does so.

This afternoon...southerly flow will strengthen ushering in deep
moisture across the midsouth. Precipitable water values will
increase from less than 1.5 inches today to in excess of 2.25
inches by tomorrow afternoon. Showers and thunderstorms will be
scattered late this afternoon...most numerous in east
Arkansas...becoming widespread across all of the midsouth by
middle morning Saturday. The heaviest rain is expected Saturday
afternoon...lasting into Sunday. There is not expected to be much
in the way of dynamic support for severe thunderstorms...but
lightning will likely be abundant and rainfall will be heavy at
times. Did not add any mention of heavy rainfall to the severe weather potential statement...but
if precipitable waters get as high as the NAM indicates...near 2.5 inches...we
may begin to see some localized flooding issues by Sunday morning.
Temperatures over the weekend will be much cooler...several degrees
below normal...with highs in the middle 80s.

Monday into the middle of next week...a broad trough will
transition into zonal flow from the plains across the southeastern
US. Temperatures will trend warmer. Guidance brings highs back
into the middle 90s by Tuesday. That seems a bit warm given the
overall pattern. Scattered showers/thunderstorms should also help
to keep temperatures down a bit so will undercut guidance highs by
2-4 degrees for most of next week. Do not see any overly organized
weather systems in the making through the end of the week...expect
gradually warmer temperatures...near to slightly above normal
after midweek with at least a slight chance of thunderstorms each
period...most likely during the afternoons.

30

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Aviation...
12z taf cycle

VFR conditions should persist for most of the forecast period.
Some fog has formed in the kmkl area producing MVFR visibilities
which should end shortly after sunrise. Some scattered showers are
possible overnight. Winds will be mainly from the south at 5 to 10
knots today then diminish tonight.

Ars

&&

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

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