489
FXUS63 KIND 101803
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
203 PM EDT Mon Aug 10 2026

.KEY MESSAGES...

- Hot and humid through at least mid week, with daily chances for
  showers and storms...especially through Friday morning

- Multiple rounds of severe storms will be possible from early
  today through at least Wed night...w/damaging winds, heavy
  rainfall/flash flooding the primary threats

&&

.DISCUSSION (This evening through Monday)...
Issued at 201 PM EDT Mon Aug 10 2026

Surface analysis early this afternoon shows southwest flow in place
across Indiana. This was due to a weak trough of low pressure
stretched from northern Michigan to IA and NRN KS and strong high
pressure in place across the southeastern states. GOES19 shows
scattered clouds were still found across central Indiana with more
abundant cloud cover over MO and IL where light showers were
present. Dew points were quite high, in the lower 70s. Aloft, water
vapor shows mainly a NW flow in place. streaming from MT and WY,
across the upper midwest, before slipping slightly south to the
southern Great Lakes and northeastern states. A weak disturbance was
found over IA, helping to trigger those light showers to the SE.

Tonight...Uncertainty remains high for shower and storm chances.
Forecast soundings show deep CAPE available this evening but a CAP
appears to remain in place within the lower levels, limiting deep
convection. Provided the CAP holds, dry weather will be expected
through much of the evening across and into the overnight. Some of
the forcing to the west within the NW flow aloft should propagate
across northern Indiana overnight. This will be our best triggering
feature tonight. Thus will try and limit pops to the northern and
northeast parts of the forecast area where those dynamics are more
likely to pass. Caveat and low confidence remains for isolated
showers or storms late this afternoon and into the evening. The warm
and humid air mass in place will result in lows in the upper 60s and
lower 70s.

Tuesday and Tuesday Night...

Models agree with more forcing aloft within the NW flow aloft
passing across Central Indiana during the afternoon and evening
hours. This forcing along with the very warm and moist airmass in
place will be favorable for additional shower and storm development
on Tuesday afternoon. Forecast soundings show deep CAPE across the
area with values over 3300 J/KG. Also PWATS will be over 2 inches.
HRRR suggests an area of thunderstorms over Central Indiana during
peak heating hours on Tuesday afternoon and into the evening. These
storms will have the potential to be severe with strong updrafts
capable of producing damaging straight line winds and heavy rainfall
resulting in flooding. Confidence on precise timing and locations
remain low. This will use high pops over a larger window late
tomorrow and tomorrow evening. Again, westerly flow and a warm and
humid air in place will allow for high temperatures in the upper 80s
to around 90.

Wednesday and Wednesday Night...

The similar NW flow aloft will remain in place across Central
Indiana and the upper midwest on Wednesday and Wednesday Night.
Again, models suggest yet another wave to pass across Indiana within
this flow. Some ridging pushing easting should allow the flow to
become a bit more NW, which would allow for storm development and
propagation to be more impactful across all of our forecast area
rather than just the north. Forecast soundings on Wednesday again
suggest deep CAPE aloft, over 3500 J/KG, but a cap in place once
again through the middle of the afternoon. This should allow us to
include dry weather through the first parts of the day, followed
higher pops in the mid afternoon into the evening. Again, highs
will reach the mid to upper 80s. Once again, heavy rains will be
possible, but high uncertainty remains.

Thursday and Friday...

The upper pattern during this time is suggested to continue as NW
flow aloft, but evolve to ridging building across the central
Plains. Embedded waves within the flow are suggested to pass on
Thursday Night, with weak ridging building across IL and the western
Great Lakes. Within the lower levels a weak, warm frontal boundary
looks to be lingering across Central Indiana before sagging
southward to on Friday. This with a warm, humid and unstable air
mass in place will be sufficient to include pops, particularly on
Thursday as the best wave and lower level trough will be in place at
that time.  Again highs in the mid and upper 80s will be in place on
Thursday, with slightly cooler values on Friday as winds take a more
northeasterly component as the front sags southward.

Saturday through Monday...

Aloft, strong high pressure is suggested to set up over the lower
Mississippi valley, with a ring of fire possible set-up impacting
northern and Central Indiana. Several embedded short waves are
suggested to push across Central Indiana through this time amid the
west to northwest flow. Forecast soundings suggest a conditional
situation, with plenty of CAPE available each day yet still a CAP
suggested each day also. Thus overall, confidence remains low for
showers and storms, but enough ingredients remain present to
necessitate  at least some mention of pops. Above normal
temperatures are expected to continue this weekend.

&&

.AVIATION (18Z TAF Issuance)...
Issued at 1250 PM EDT Mon Aug 10 2026

Impacts:

- Convection possible around and after 00z this evening, best
  chances from LAF to IND northward.

- South-southwest winds gusting to near 20KT this afternoon.

Discussion:

Mainly VFR conditions this TAF period. High uncertainty regarding
precipitation chances due to warm and humid air in place with ACARS
soundings showing minor capping in place near 875mb. As peak heating
is reached this afternoon, Isolated convection cannot be ruled out
through the later afternoon and evening, although any coverage
should be quite limited.

Better forcing may arrive overnight, mainly impacting LAF and IND as
best dynamics should be found across northern Indiana. HRRR suggests
best chances for development will remain north of of TAF site and be
limited to the overnight hours. Thus have included a VCSH mention for
the evening and overnight hours just due the very low confidence for
possible storm development.


&&

.IND WATCHES/WARNINGS/ADVISORIES...
Heat Advisory until 8 PM EDT this evening for INZ051>053-060>062-
067>070.

&&

$$

AVIATION...Puma
DISCUSSION...Puma