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Area forecast discussion 
National Weather Service Memphis Tennessee
1148 PM CDT Tuesday Jun 30 2015

Update...

Updated for 06z aviation discussion...

&&

Previous discussion... /issued 831 PM CDT Tuesday Jun 30 2015/

Update...

Much quieter evening compared to Monday night. Only minor
adjustments needed to current forecast. Will trim back probability of precipitation a bit
given current trends. However...hrrr/18z nam12 suggest at least
isolated/widely scattered showers/storms may develop later
tonight...so will not remove completely.

Overall trend of increasing pop and quantitative precipitation forecast looks good for the remainder
of the week. We should see precipitation ramp up during the day
Wednesday...with late Wednesday through early Friday showing the
greatest potential for heavy precipitation. Later forecast updates will
provide more detail regarding timing...amounts...and location of
precipitation areas.

Gw

Previous discussion... /issued 336 PM CDT Tuesday Jun 30 2015/

Discussion...

Current 500 mb analysis places a deep trough over the eastern
Continental U.S....with a strong ridge centered over The Rockies. This
pattern has brought below normal temperatures to the
midsouth...and will continue to provide cooler than normal
temperatures and above normal precipitation amounts to the region
through the Holiday weekend.

Northwest flow aloft will allow several impulses to move over the
region through the weekend. The first of these will move through
the region Wednesday night and Thursday...leading to mesoscale convective system
development over southern Missouri. With guidance suggesting cape
values in excess of 2000 j/kg...a low level jet in place with
maximum winds over 40 kts...and 0-1 km shear values in excess of
20 kts...a forward propagating mesoscale convective system is likely to cross the region
early Thursday. Damaging winds and heavy rainfall will be the
primary threats...with precipitable water values in excess of 2.00 inches in
some locales. A Flash Flood Watch has been debated...however given
the disagreement on heaviest quantitative precipitation forecast placement between the
models...too much uncertainty exists for issuance at this time and
the risk will continue to be monitored for widespread flash
flooding. Localized flash flooding will be possible...especially
in those areas that have received heavy rainfall in events during
the past several days.

Wednesday night and Thursday will hold the best chance for any
strong to severe storms and/or heavy rainfall throughout the next
seven days. However daily chances for showers and
thunderstorms...some of which could be strong to severe...will
exist through the weekend. Latest weather prediction center quantitative precipitation forecast
for the next seven days has nearly 6 inches of precipitation for
locations in west Tennessee and east Arkansas. Models indicate a weakening of
the trough by late in the weekend as the ridge begins to build in...allowing
relief from rain and a gradual warming of temperatures to near
normal for early July.

Zdm

Aviation...

06z tafs

VFR conditions expected to continue through Wednesday morning with
gradually increasing clouds associated with convective complex
moving southeast from MO. Thunderstorms in the vicinity is expected at mkl and jbr after
12z Wednesday with periods of thunderstorms and rain during the morning. It will
take a little longer for thunderstorms in the vicinity to reach mem and tup but this is
expected after 17z on Wednesday. Periodic MVFR conditions are
possible with lowering ceilings associated with thunderstorm complex.
Thunderstorms in the vicinity has been added to all terminals through the remainder of the
taf period with significant uncertainty existing with regard to
timing and evolution of the complex on Wednesday.

Tvt

&&

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

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