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Area forecast discussion...updated 
National Weather Service Aberdeen South Dakota
1250 PM CDT sun Jul 5 2015

Update...
issued at 1242 PM CDT sun Jul 5 2015

Aviation discussion has been updated below for 18z tafs.

Update issued at 1049 am CDT sun Jul 5 2015

Lingering showers are quickly dissipating over Corson and Dewey
counties this morning. There is some residual stratus with these
storms but not enough to hamper daytime heating across the eastern
third of the County Warning Area. Dewpoints across the region are sitting in the
middle to upper 60s...and models still show ml cape values topping
out over 3000 j/kg this afternoon. As previously mentioned shear
is best behind the front...but ingredients still look to be
setting up as planned this afternoon. Hail and damaging winds are
still the main threats...but cannot rule out an isolated tornado.
Storm Prediction Center still has the region in an enhanced risk. Overall the timing
of the forecast looks fine...may have to make a few adjustments to
probability of precipitation early this afternoon...but no major changes to the going
forecast.

&&

Short term...(today through Tuesday afternoon)
issued at 421 am CDT sun Jul 5 2015

Convection continues to to advect east ahead of a weak shortwave
embedded in a tropical plume that has rounded the western Continental U.S.
Ridge...with an elevated mixed layer also developing across the County Warning Area.
700mb temperatures will continue to increase to between +10 to +15c
through the day. Elevated convection is depicted within a majority
of high res guidance moving out of Montana later this am as well.

But most of the focus is on this evening. Given 700mb temperatures
and forecasts being a little slower bringing the surface front through
the County Warning Area...reduced probability of precipitation for the today period. Best jet dynamics are
closer to the evening hours...with cams developing convection
between 00 and 06z. All cams generate convection ahead of the
shortwave trough...along and on the cool side of of the surface
front...where the cap is weaker. MLCAPE values could top 5000 j/kg
in this regime...though shear is also mainly limited to the cool
side of the front. This makes discerning the storm environment Muddy
at best. Cams assist in this though...depicting one or more
complexes developing and pushing across the County Warning Area...which makes since
given high LCLs and dcape values around 2000j/kg. Thus...will
maintain severe/heavy rain wording.

With northwest flow...NAM profiles are weakly unstable up to 700mb.
Thus...convective showers are possible Monday. High pressure
overhead for Tuesday will lead to dry conditions. Temperatures will
be cooler than normal Monday and Tuesday as well.

Long term...(tuesday evening through saturday)
issued at 421 am CDT sun Jul 5 2015

A shortwave will approach from the west/southwest on Wednesday
bringing chances for showers and thunderstorms. With a northern
plains low moving out of Montana on Thursday night/Friday the potential for
storms ahead of and with this system will continue as a decent
southerly moisture feed and weak low level jet set up. Shortwave activity and
an upper low will move over the region late Sat keeping probability of precipitation in the
forecast. Due to uncertainty of shortwave energy stuck with
superblend probability of precipitation.

Temperatures will feature an upward trend with highs in the 70s on
Wednesday climbing into the middle to upper 80s by Saturday.

&&

Aviation...(for the 18z tafs through 18z Monday afternoon)
issued at 1242 PM CDT sun Jul 5 2015

Showers and thunderstorms are expected this afternoon into the
early evening...possibly affecting the taf sites. Will include
thunderstorms in the vicinity mention at this time until timing and placement of storms
become more clear. MVFR ceilings/visibility may develop in or near
thunderstorms. A frontal boundary crossing the area today will
switch surface winds from a south/southwest direction to more of a
north/northeast direction.

&&

Abr watches/warnings/advisories...
South Dakota...none.
Minnesota...none.
&&

$$

Update...tmt/serr
short term...Connelly
long term...wise
aviation...tmt

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