171
FXUS63 KIND 041700
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
100 PM EDT Fri Jul 4 2025

.KEY MESSAGES...

- Hot today with highs into the lower 90s

- Heat indices mid 90s to near 100 degrees this weekend

- Scattered showers and thunderstorms return to the forecast
  Sunday, then daily storm chances persist into next week

&&

.FORECAST UPDATE...
Issued at 955 AM EDT Fri Jul 4 2025

Thunderstorms were across southern Wisconsin, northern Illinois, and
southern Lake Michigan this morning. Cirrus from these storms were
moving south across Indiana.

The thunderstorms should continue to develop mainly east more than
south, toward better instability. An upper ridge will also help keep
this convection out of central Indiana. Will continue with a dry
forecast.

Did increase cloud cover some today with the cirrus moving south
into the area. The thicker cirrus should remain across northern
portions of the area. Some cumulus will pop up again today, so
overall sky conditions will become partly cloudy.

Temperatures have risen nicely this morning, even with the cirrus.
For now have left high temperatures alone, but will have to monitor
the effect of the cirrus on temperatures to see if adjustments need
to be made later today.

&&

.SHORT TERM (Today and Tonight)...
Issued at 254 AM EDT Fri Jul 4 2025

Clear skies were across the forecast area early this morning with
high pressure in control. High clouds from a convective cluster over
the upper Midwest was expanding southeast quickly towards the lower
Great Lakes. 06Z temperatures ranged from the upper 60s to mid 70s.

Upper ridging over the central Plains will expand east into the Ohio
Valley today with high pressure at the surface remaining across the
region as well. This will keep convection well to the north of
central Indiana through tonight in closer proximity to a warm front
extending from the northern Plains southeast into lower Michigan. It
will be a hot Independence Day with a subtle uptick in humidity as
return southerly flow on the back side of the high will signal the
beginning of a return to more oppressive conditions for the weekend.

Much drier air resides over the region but the expanding cirrus from
the convective cluster over the upper Midwest may be able to work
into northern portions of the forecast area near or just after
daybreak before gradually diminishing through midday. Model
soundings are supportive of scattered diurnal cu development for
this afternoon but the presence of a mid level cap will mitigate any
isolated convection and keep dry weather for afternoon and evening
outdoor holiday activities.

Additional mid and high level cloud debris from renewed convection
over the Great Lakes late day into this evening may again drift into
the northern portions of the forecast area prior to diminishing.
Otherwise...skies will revert to mainly clear for the overnight.

Temps...even with the potential for some cirrus to slip into the
region from the north...do not see that being a deterrent from most
of the forecast area making it to 90 degrees this afternoon.
Dewpoints should reside in the low to mid 60s during peak heating...
making for heat indices reaching the mid 90s and generally providing
a typical mid summer day. Lows tonight will be a couple degrees
either side of 70.

&&

.LONG TERM (Saturday through Thursday)...
Issued at 254 AM EDT Fri Jul 4 2025

A classic summertime weather pattern continues through the weekend
for all of Central Indiana. While conditions are not expected to be
as oppressive as they were last week, both humidity and temperatures
will continue to rise over the next several days. The weather
pattern becomes active again Sunday through next week as daily storm
chances are back in the forecast.

Strong ridging across the Central and Northern Plains slides
eastward this weekend, resulting in a gradual warming and moistening
trend as the core of the heat and humidity push closer to the state.
Expect each day to be a few degrees warmer and more humid than the
previous day in this pattern with highs reaching the lower 90s for
the 4th of July and this weekend. Dew points may reach or exceed 70
degrees again, especially by Sunday, resulting in heat indices
approaching the 100 degree mark again during the afternoon hours.

Large-scale ridging begins to break down over the weekend with
guidance consistently to show a weak trough and cold front
approaching from the northwest on Sunday. Latest guidance has been
more consistent regarding the timing of the approaching front and
storms on Sunday, with the best threat for storms during the evening
and into the nighttime hours. Confidence is high that much of Sunday
will be hot and relatively dry, with the storm threat increasing
from northwest to southeast the during the evening. At the moment,
confidence is low on the severe threat with these storms as shear
looks too weak to support widespread organization. With such a
moist, unstable environment though, the possibility is there for any
storm to briefly pulse up to severe levels before collapsing. The
main threats will likely be brief periods of heavy rain, gusty
winds, and lightning. Best threat for storms looks for be for the
northern and western half of the state with convection significantly
diminishing during the overnight hours.

The pattern going into next week looks fairly typical for July with
highs in the 80s, humid conditions, and additional storm chances.
Keeping a chance of storms in for Monday as there is lower
confidence on the timing of the aforementioned frontal passage.
Tuesday could potentially be the driest day next week as longer
range guidance and ensembles indicate a more active pattern setting
up mid next week and beyond with more frequent precipitation
chances... yet still warm and humid.

&&

.AVIATION (18Z TAF Issuance)...
Issued at 100 PM EDT Fri Jul 4 2025

Impacts:

- Brief ground fog possible near sunrise

Discussion:

Scattered cumulus will dissipate early this evening then pop back up
Saturday. Cirrus from convection well to the north will pass through
from time to time.

Light winds overnight and low level moisture could lead to some
ground fog at all but KIND near sunrise Saturday, but odds are too
low to mention anything below VFR.

&&

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

$$

UPDATE...50
SHORT TERM...Ryan
LONG TERM...CM
AVIATION...50