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Area forecast discussion 
National Weather Service Memphis Tennessee
1002 am CDT Thursday may 28 2015

Update...

No changes made to the forecast this morning. Some questions exist
with regard to high temperatures today as cloud cover is
prevalent...but still feel highs will be reached with some breaks
in cloud cover noted on visible satellite imagery. Secondary
concern is ongoing mesoscale convective system across Oklahoma which some hi-res guidance
show moving into western portions of the County Warning Area prior to 00z. As of
now...believe these solutions to be too aggressive so will defer
to the afternoon forecast package and take a longer look.

Tvt

&&

Previous discussion... /issued 404 am CDT Thursday may 28 2015/

Discussion...surface analysis this morning places a quasi-
stationary boundary southern Illinois and southern Missouri.
Infrared satellite trends show partly to mostly cloudy skies along
the Tennessee River and portions of east/northeast Arkansas...and
mainly clear skies along the Mississippi River. As of 3 am
CDT...temperatures across the middle South Range from the lower 60s
along the Tennessee River...and predominantly middle to upper 60s
across the remainder of the middle south.

A potential for patchy fog will persist across the middle south
through sunrise as temperatures are approaching surface dewpoints
with nearly light to calm winds. A weak shortwave ridge will be
in place across the lower Mississippi Valley today with overall
shear expected to remain very weak. /0-6 km bulk shear values
around 10 kts/ at this time...think overall coverage will be
somewhat less than yesterday as the main triggering mechanism for
any shower/thunderstorm activity will be convective temperatures
being reached this afternoon as temperatures rise into the lower
to middle 80s. Weak overall shear combined with surface based
instability increasing to at or above 2000 j/kg and precipitable
water values between 1.7 to 2 inches suggest main convective Mode
will be pulse type thunderstorms with strong to damaging wind
gusts from wet microbursts along with localized heavy rainfall
being the potential severe weather threats. Any convective
activity should decrease in coverage with the loss of daytime
heating tonight.

Not much change is expected in the overall synoptic pattern for
Friday across the middle south with perhaps some slight weakening in
middle level heights. As a result...would anticipate similar
conditions to today but a bit more coverage in showers and
thunderstorms.

Long term models still indicate a cutoff upper level low
developing across the lower Mississippi Valley late this weekend
into next week. This will result in shower and thunderstorm
chances each day with the best coverage most likely occurring
during the afternoon and evening hours each day. A few strong to
perhaps isolated severe thunderstorms may be possible during the
afternoon and evening hours each day with damaging winds and
localized heavy rainfall as the severe weather threats.
Temperatures will be slightly cooler due to the convective chances
and the cutoff upper level low in place across the region.

Cjc

Aviation...

12z tafs

IFR/MVFR will gradually improve to VFR through 18z...with
deepening mixed layer from daytime heating. Isolated thunderstorms and rain will be
possible this afternoon...mainly near left over convective
boundaries near the Tennessee River valley. Coverage near tup likely
sufficiently limited to warrant only a thunderstorms in the vicinity.

Pwb

&&

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

$$

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