Area Forecast Discussion
Issued by NWS Indianapolis, IN

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FXUS63 KIND 260736

Area Forecast Discussion
National Weather Service Indianapolis IN
336 AM EDT TUE JUL 26 2016

The SYNOPSIS...NEAR TERM and SHORT TERM Sections have been updated below.


Issued at 309 AM EDT Tue Jul 26 2016

Off and on storm chances will continue until mid way through the
weekend when upper ridging reestablishes over the area. Near
normal temperatures should be the rule through most of the period,
with Wednesday looking like the warmest day with highs in the
upper 80s to around 90.


.NEAR TERM /Today/...

Issued at 309 AM EDT Tue Jul 26 2016

Could see some patchy fog near daybreak with dew point
depressions of only a degree or two in several spots across the
forecast area, but that should burn off or mix out quickly after
sunrise. Hi res guidance shows a line of showers and thunderstorms
forming along a boundary currently stalled out across southern
central Indiana by if not before mid morning and hanging around
into the afternoon/evening hours before moving off to the
southeast. Think coverage could be somewhat overdone given several
runs have been showing more currently than what is seen on radar
over Illinois and moisture looks overdone. However enough
potential there to bring in high chance pops along the southern
border this afternoon and ramp up to it this morning. For
temperatures most solutions are in the mid 80s, and think this is
reasonable given the potential for cloud cover throughout much of
the day and some rain.


.SHORT TERM /Tonight through Monday/...

Issued at 309 AM EDT Tue Jul 26 2016

Tonight will see the boundary shift south and the storm chances
should go with it. Will leave a slight chance in the south as a
wave moves along the front. On Wednesday increased to a chance
along the far southern border as the front could start to move
back north. For Wednesday night through Thursday night, a
stronger upper wave should combine with the front to produce some
solid thunderstorm chances Wednesday night and with likely PoPs in
the south and southeast Thursday. Chances continue to Thursday
night and beyond.

For temperatures think mainly mid 80s are a good bet given the
potential for thunderstorms and cloud cover through most of the
period and cooler 850 mb temperatures. Possible exception to this
is on Wednesday when PoPs are confined to the southern counties
and thus could see upper 80s especially north where ample sunshine
is possible.

At this point looks like axis of heavy rainfall will set up south
of the area, but will need to monitor with upcoming forecasts
repeat development along the boundary if it becomes stationary
rather than meandering.


.LONG TERM /Friday through Monday/...

Issued at 237 AM EDT Tue Jul 26 2016

ECMWF suggests a low pressure system and cyclonic flow pushing
through the Great Lakes and Indiana on Friday and Saturday. Aloft
ECMWF suggests a weak...broad trough in place across the upper
midwest and great lakes. Superblend keeps chc pops in place as
these features passes...which seems reasonable.

As the low moves to the east coast on Sunday through Tuesday...High
pressure...ridging and subsidence is expected as depicted by the
ECMWF. Given this and the relatively cooler and drier air mass
that is expected across the area...have tried to add value to the
forecast by removing pops as suggested by superblend.


.AVIATION /Discussion for 260600Z TAF Issuance/...
Issued at 1230 AM EDT Tue Jul 26 2016

MVFR conditions possible at times through mid morning in fog
otherwise predominantly VFR expected.

Convoluted forecast as diffuse frontal boundary becoming quasi-
stationary over southern portions of central Indiana for much of the
period. With only weak high pressure located to the northwest...dry
air and deeper subsidence has been unable so far to make much of a
southward push into the region. Model soundings and RH progs showing
boundary layer moisture lingering and expanding over much of central
Indiana along and south of I-70 overnight...with the possibility of
stratocu to go along with patchy fog. With that being said...lower
level cloud coverage being overdone by most models currently. Only
terminal where there is reasonable confidence at minimal ceilings is
KLAF but even here there are likely to be visibility restrictions
during the predawn through daybreak period.

With the front stalling in south central Indiana...HRRR/WRF/NAM all
try to develop few showers into areas as far north as the I-70
corridor as early as the predawn hours and continuing into Tuesday
as weak disturbances ride the boundary. Mesoanalysis indicating
a zone of enhanced convergence over southern portions of central
Indiana in the vicinity of the front and expect any precip would
develop in this area if at all. KBMG would stand the greatest chance
to be impacted by rain showers but overall...have very low
confidence in any precip impacting the terminals at this point
through this evening. Expect additional cu development during the
day with the amount of low level moisture present. May see more
pronounced scattering of clouds this evening as boundary shifts
further south and drier air attempt to spread in from the north.


.IND Watches/Warnings/Advisories...


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