891
FXUS63 KIND 251026
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
626 AM EDT Wed Jun 25 2025

.KEY MESSAGES...

- *HEAT ADVISORY* continues through late day Friday

- Heat indices up to 100-107 degrees and low temperatures near or
  above 75 degrees through Friday

- Scattered daily afternoon showers/t-storms, isolated strong to
  severe wind gusts are possible

&&

.SHORT TERM (Today and tonight)...
Issued at 252 AM EDT Wed Jun 25 2025

- HEAT ADVISORY REMAINS IN EFFECT THROUGH THE PERIOD

- Scattered diurnal showers and storms with the potential for
  isolated strong to severe wind gusts

Expect hot and muggy conditions again today with the overall weather
pattern remaining similar to yesterday. A heat advisory is in effect
through the period as heat indices are likely to peak around 100-
106F in most locations by this afternoon. Little to no relief from
humidity the past few nights will also exacerbate the heat threat so
make sure to take extra precautions if you are planning to spend
time outdoors. Drink plenty of water to stay hydrated, take frequent
breaks in AC or shaded areas, and limit time outside. Also check on
neighbors and relatives.

Scattered diurnal showers and storms will develop later today as
daytime heating over an anomalously moist PBL promotes strong
destabilization. Isolated strong to severe wind gusts are possible
as forecast soundings depict high DCAPE values supported by steep
low-level lapse rates and mid-level dry air. Weak deep-layer shear
should result in storms quickly collapsing. Any stronger
thunderstorms that begin to collapse will pose the greatest threat
for downbursts. Locally heavy rainfall and lightning are also
threats from storms today.

Latest CAMs suggest greater coverage of storms today compared to
yesterday. This is likely due to deeper moisture in place and the
upper ridge overhead gradually weakening. Convection should
diminish after sunset as the loss of daytime heating leads to the
PBL stabilizing. Expect highs to generally reach the low 90s
during the afternoon with lows in the 70s again tonight.

&&

.LONG TERM (Thursday through Tuesday)...
Issued at 252 AM EDT Wed Jun 25 2025

...Heat Advisory Continues through Friday...

Thursday and Friday -

More of the continued hot and humid weather appears to remain in
place across Central Indiana during this time. The strong area of
upper level high pressure in place over the southeastern states will
remain in place through Friday along with its associated area of
surface high pressure. This will result in continued hot and humid
southerly flow into Central Indiana, which will bring daily chances
for isolated, diurnal and unorganized afternoon and evening showers
and storms. The main jet flow will remain well north of Indiana,
helping to prevent the arrival of any organized forcing. Thus more
persistence type weather will be expected with highs in the low to
mid 90s and low to mid 100s for the heat index. Again, afternoon
shower and thunderstorm coverage will be small and low pops will be
used.

Saturday Through Monday -

The strong upper ridging looks to begin breaking down on Saturday,
leading to a more zonal flow across the Great Lakes. A pair of weak
short waves are then shown to push toward and across Indiana on
Saturday and again on Monday. Given little change to our hot and
humid air mass in place across Central Indiana, this organized
forcing allows for better confidence for more widespread afternoon
and evening showers and thunderstorms on each day. Also, additional
cloud cover and a lack of subsidence expected through the weekend
should result in slightly cooler temperatures, which at this time,
should allow us to forgo a continuation of the Heat Advisory, at
least for now. Will trend to high chance pops on both Saturday and
Monday afternoons.

Tuesday -

Models here have trended toward upper ridging in place over the high
plains and a trough over the Great Lakes, previously beginning the
day in Indiana. This will result in northwest flow in place aloft
and allow for cooler and less humid air to arrive. Furthermore a cold
front is suggested to be exiting Indiana in the morning, leading to
NW surface flow. For the moment, some pops will be needed in the
morning on Tuesday due to possible timing adjustments on the frontal
passage, but confidence is growing here for a return to near normal
high temperatures.

&&

.AVIATION (12Z TAF Issuance)...
Issued at 625 AM EDT Wed Jun 25 2025

Impacts:

- Scattered showers and storms after 19Z today

Discussion:

Expect predominately VFR conditions through the period. However,
scattered showers and storms are possible after 19Z. Brief MVFR or
worse visibilities will be the main impact along with potential TSRA
that could strike a TAF sites, however confidence for coverage and
precise timing remains low due to the diurnal nature of the
convection and weak overall flow.

Loss of heating this evening will lead to diminishing convection.
Look for winds to remain light and out of the S/SW during the
period. Storms this afternoon and evening could contain strong gusty
winds though.

&&

.IND WATCHES/WARNINGS/ADVISORIES...
Heat Advisory until 8 PM EDT Friday for INZ021-028>031-035>049-
051>057-060>065-067>072.

&&

$$

SHORT TERM...Melo
LONG TERM...Puma
AVIATION...Melo