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Area forecast discussion 
National Weather Service Indianapolis in
435 am EDT Sat Aug 2 2014

the aviation section has been updated below.


issued at 332 am EDT Sat Aug 2 2014

Scattered thunderstorms will be possible again today as an upper
level wave tracks east. Weak high pressure will build into central
Indiana tonight...with dry weather expected through Monday.
Unsettled weather will then return with daily chances for
thunderstorms through the remainder of the week as a frontal
boundary settles across the region.


Near term /today/...
issued at 332 am EDT Sat Aug 2 2014

Upper wave centered over the region early this morning producing
clouds and isolated convection. With storm motions again at 5kts or
less...cells are very slow movers. Temperatures at 07z were in the 60s
across central Indiana.

Yet another day with the potential for scattered convection as the
upper wave moves slowly across the area. Only difference today from
Friday will be the location of greatest convective concentration.
Expect this to focus more over the eastern forecast area as the wave
treks into Ohio by this afternoon. Will carry highest probability of precipitation at 40-50
over these areas...gradually tapering further to the west. Despite
lower threats over western forecast area...again storms are possible
anywhere today in the warm moist airmass.

Locally heavy soakers will be the primary threat from convection
with slow storm motions. Thermodynamic profiles not quite as
favorable as they were Friday...but still indicate potential for
gusty winds and hail from stronger storms within the weakly sheared
environment present. Convective coverage should gradually diminish
towards early evening as the wave shifts further east into Ohio.

Temperatures...MOS guidance again appears to be overdoing available warmth
today considering the above thoughts and virtually identical thermal
profiles to Friday. Undercutting MOS by a couple degrees for


Short term /tonight through Monday night/...
issued at 332 am EDT Sat Aug 2 2014

Forecast challenges focus on temperatures as high pressure brings mainly
dry weather through the period.

The arrival of weak surface high pressure and subtle ridging aloft
late tonight and Sunday will expand into the Ohio Valley behind the
departing wave. Model soundings showing the development of a middle
level cap and subsidence aloft...setting the stage for a pleasant
Sunday across central Indiana. Convective temperatures around 80 will
support afternoon cumulus development. The surface high remains across
the region Monday as the upper trough attempts to reestablish with a
wave aloft rotating into the Great Lakes.

Cap is weaker on Monday but still present...and should keep
convection from developing over the forecast area in the absence of
more substantial forcing aloft. Yet another wave aloft will approach
from the northwest late Monday night and may spread isolated
convection into the northern Wabash valley prior to daybreak
Tuesday. With little instability however...plan on maintaining a dry
forecast at this time.

Temperatures...generally went at or just below mavmos guidance for highs
Sunday and Monday. Low level thermals will warm and with more
sunshine both days...should see temperatures rise a few degrees over highs
Friday and today. Expect a broad spectrum in lows between the cities
and rural areas with mainly clear skies and light winds. Cooler
mavmos captured this well and was preferred for lows throughout the


Long term /Tuesday through Friday/...
issued at 332 am EDT Sat Aug 2 2014

An upper trough over the eastern third of the U.S. Will allow
several upper waves to move through central Indiana keeping low
chances for thunderstorms in the forecast through the long term.
There is little to key in on for timing with little in the way of
surface forcing and high model variability regarding timing of
individual waves. Thus only made minor quality control adjustments
to low to middle chance probability of precipitation from initialization through the period.
Temperatures look very similar throughout with near normal highs in
the low to middle 80s and lows in the 60s to around 70.


Aviation /discussion for the 020600z tafs/...
issued at 1251 am EDT Sat Aug 2 2014

A few showers and storms across central Indiana but none of them
over a taf site. Still little way to discern if one will pop over a
taf site and with their avoidance thus far at kind changed to a
tempo group for MVFR fog with vcsh prevailing. Went more optimistic
this go round with showers avoiding the sites but still included
generally IFR /MVFR for kind/ tempo group in case a shower does pop
up. Will leave thunder out. Previous discussion follows...

Otherwise...fog is beginning to form earlier than expected despite
the cloud cover. Areas of IFR visibility restrictions look more
likely will add them to the forecast roughly
020700z-021300z. Ceilings generally above 050 expected through about
middle morning Saturday before scattering out as the wave departs.
Scattered diurnal clouds based around 030 expected to develop around
midday Saturday.

No wind issues expected through 021800z.


Ind watches/warnings/advisories...none.



near term...Ryan
short term...Ryan
long term....cp

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