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fxus63 kind 250340 

Area forecast discussion
National Weather Service Indianapolis in
1140 PM EDT Sat Aug 24 2019

the aviation section has been updated below.


issued at 313 PM EDT Sat Aug 24 2019

An upper level system combined with a surface cold front will bring
rain chances to central Indiana Sunday afternoon through Tuesday
evening. Dry weather should then return for the remainder of the
week. Temperatures will be below normal for much of the period.


Near term /tonight/...
issued at 907 PM EDT Sat Aug 24 2019

Forecast in good shape. No updates planned at this time. Previous
discussion follows.

Quiet weather will continue through tonight across the area with
high pressure in control.

The cumulus clouds across the area this afternoon will dissipate,
but a gradual increase in high clouds can be expected tonight with
warm advection beginning aloft. Will have skies become partly cloudy
most areas during the night.

With the increase in clouds, the blend's lows in the mid to upper
50s look reasonable.


Short term...(sunday through tuesday)
issued at 313 PM EDT Sat Aug 24 2019

Models are close enough that the National blend of models
initialization was accepted for most items.

Warm advection will continue on Sunday as an upper trough approaches
the area. At the surface though, there will remain an easterly
component to the wind, which will help keep dry air in the lower
levels. Thus will keep the forecast dry for the entire area through
18z, then allow low pops to develop in the southern quarter or so of
the forecast area as some better moisture finally arrives.

Isentropic lift will increase during the night Sunday night and into
Monday as an upper trough moves in. A decent flow from the Gulf of
Mexico will bring in good moisture, with precipitable water values
around 2 inches arriving by Monday. Will have likely pops in the
south by overnight Sunday with likely pops all areas on Monday.

Instability is weak through Sunday evening, so will have just
showers most areas. Enough instability moves in after that to have a
thunder mention, but don't see high enough instability for a severe

With the high precipitable water values Monday, wouldn't rule out
some locally heavy rain, mainly in any thunderstorms that can

There should be a lull Monday night with the area between systems,
but then a cold front and another upper system moves in on Tuesday.
These will bring enough forcing for likely pops most areas then.

The intialization's temperatures were reasonable for the most part.


Long term /Tuesday night through Saturday/...
issued at 218 PM EDT Sat Aug 24 2019

Models show a fairly dry and mild period through the long term.
Will have one period at the very start with pops as a frontal
system exits the area, otherwise will go with a dry forecast as
surface high pressure controls the area.

Temperatures will generally be in the upper 70s to low 80s with
lows in the mid 50s to low 60s.


Aviation /discussion for the 250600z tafs/...
issued at 1140 PM EDT Sat Aug 24 2019

Some diurnal cloud based around 035-040 expected to develop
towards the midday hours of Sunday, along with no restrictions to

Surface winds 070-090 degrees at 5-8 kts overnight will veer
slightly to 090-110 degrees at 9-12 kts by midday Sunday.


Ind watches/warnings/advisories...


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