497
FXUS63 KIND 050641
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
241 AM EDT Fri Jul 5 2024

.KEY MESSAGES...

- Chances for morning showers and isolated thunderstorms.
- Becoming partly cloudy this afternoon and mostly clear tonight.
- Rain chances return late Monday into Tuesday.

&&

.SHORT TERM (Today and tonight)...
Issued at 240 AM EDT Fri Jul 5 2024

Surface analysis early this morning shows low pressure in place over
the upper Mississippi River Valley with a cold front extending south
across eastern IA, western IL to SE MO. A convective complex was
found over SE MO, ahead of the front and was showing signs of
warming tops.  Flow across Central Indiana was weak and
disorganized. Dew point depressions across the area were less than
2F and some areas of fog were developing.

Today...

Upper pattern today shows a broad upper trough in place across the
northern CONUS with a trough axis over western MN and western IA.
This trough axis is expected to push east to the Great Lakes and
toward Central Indiana today. The accompanying surface low will also
reach Michigan and drag a cool front across Central Indiana by late
afternoon. HRRR suggests best forcing will be the result of the
decaying convective complex over MO as is reaches Central Indiana
this morning and passes by this afternoon. This system will be
passing across Indiana during the diurnal minimum, thus
showers/storms will look to be more scattered in nature. Hence only
chance pops will be used.

By this afternoon the lower level flow becomes more westerly in the
wake of the front as forecast soundings start a trend of drying out.
Thus will try and contain pops to hours before 18Z.  Highs in the
lower and middle 80s are expected.

Tonight...

Broad troughing aloft looks to remain in place over the CONUS
tonight. However little to no forcing appears to push across Central
Indiana. Meanwhile within the lower levels high pressure over the
plains is expected to build eastward into the Ohio Valley. This
should lead to mostly clear skies and light winds overnight.
Forecast soundings support this with a dry column through the night.
Lows overnight in the lower to middle 60s will be expected.

&&

.LONG TERM (Saturday through Thursday)...
Issued at 240 AM EDT Fri Jul 5 2024

Saturday Through Tuesday.

A quiet and cool start  to the weekend is expected with zonal flow
aloft and light westerly winds expected for Saturday. Slightly drier
air will move into central Indiana after the rain comes to an end on
Friday with afternoon dewpoints around 60 with highs near 80. Dry
and quiet conditions will continue into Sunday with a gradually
warming trend going into early next week as the surface flow becomes
more southerly. Skies will remain mostly clear through Sunday night
before the pattern shifts going into Monday.

A broad trough will slowly exit the Central Plains late Monday into
Monday night with a broad area of light precipitation expected to
push into Indiana during the daytime hours on Tuesday. Models are
suggesting a localized area of convergence where higher
precipitation amounts are likely, but there remains quite a bit of
model spread as to where exactly that settles.  There is some model
clustering across the upper Wabash Valley for this axis, but it may
be as far north as the Chicago area or as far south as south central
Indiana. Instability will be the limiting factor keeping the severe
potential to near zero.

Wednesday and Thursday.

Forecast confidence then falls off Wednesday into Thursday in the
aftermath of the rain on Tuesday.  There is some signs that there
could be some residual precipitation along the stalled frontal
boundary but where that stalls remains very uncertain.  Weak
northwesterly flow aloft will help to keep temperatures mild,
especially if cloud cover sticks around longer than models currently
suggest.

&&

.AVIATION (06Z TAF Issuance)...
Issued at 127 AM EDT Fri Jul 5 2024

Impacts:

- Mainly VFR conditions this TAF period.

- Brief MVFR possible 11Z-16Z with possible showers and very
isolated storms.

Discussion:

Mostly clear skies, light winds and dew point depressions less than
2F have lead to MVFR to IFR fog development. This will persist
through the early morning hours. A thunderstorm complex over SE MO
is expected to push northeast into the Ohio Valley. It is expected
to diminish somewhat upon approach, however the HRRR does continue
to suggest this decaying system to pass across southern parts of
central Indiana, possibly impacting the TAF sites. However,
confidence remains too low at this time for a specific prevailing
mention. Have used VCSH for the moment.

After this morning round of possible showers passes, forecast
soundings show a dry column with afternoon CU development as
convective temperatures are reached. A mid level inversion will
prevent deep convective growth. This should mainly be VFR CIGS.

High pressure over the plains states will build across Indiana
tonight and VFR conditions will continue under mostly clear skies
and light winds.


&&

.IND WATCHES/WARNINGS/ADVISORIES...
None.
&&

$$

SHORT TERM...Puma
LONG TERM...White
AVIATION...Puma