textproduct: Indianapolis

KEY MESSAGES

- Dry and comfortable through Wednesday

- Rain and storm chances return Wednesday night through the weekend

- Hot and humid conditions increasingly likely by early next week

DISCUSSION (This evening through Tuesday)

Issued at 257 PM EDT Tue Jun 23 2026

This afternoon through Wednesday...

Quiet weather conditions are expected as surface high pressure continues to shift east across the region. Latest satellite imagery depicts some diurnal cu has developed over portions of central IN due to convective temperatures being reached. Temperatures have already warmed into the lower 70s thanks to plentiful sunshine and a drier airmass in place. Look for temperatures to continue gradually climbing over the next few hours with highs ranging from the mid 70s to low 80s.

Light northerly surface may be limiting overall heating slightly. The drier airmass across the region and mostly limited cloud cover should continue promoting large diurnal temperatures swings. Expect lows well into the 50s as winds become very light overnight before then warming into the upper 70s to low 80s on Wednesday.

Wednesday night through Saturday night...

A low amplitude wave and associated weak surface low will move through the region Wednesday evening into the overnight hours. Modest moisture advection combined with sufficient forcing supports the potential for some convection. However, uncertainty remains on convective coverage as the antecedent dry airmass may be difficult to overcome. Recent CAM runs are catching on to this scenario showing less convective coverage. Severe weather or flooding from heavy rainfall appears unlikely given relatively weak flow aloft and lack of deeper moisture return.

Model guidance suggest the diffuse front associated with the aforementioned low pressure system stalls over central Indiana by Thursday. This will likely keep an active pattern in place through the end of the week with multiple waves tracking across the boundary. Widespread precipitation is expected late Thursday night into Friday. The greatest rain chances are focused across the southern half of the forecast area where the strongest forcing and deeper moisture overlap.

Deeper moisture lifting north along with the potential for repeated rounds of storms supports an elevated flooding threat, primarily late Thursday into Friday morning. Modest enhancement of mid-upper level flow on top of a modest-moderately unstable environment may promote a marginal severe threat, but widespread severe weather appears unlikely.

Saturday onward...

Rain chances remain in the forecast through Sunday as disturbances continue to track across the meandering frontal boundary. Long range guidance then depicts an amplifying upper level ridge shifting eastward into eastern portions of the CONUS. The ridge axis should be centered over the region late Sunday into Monday and remain persistent through at least the middle of next week before possibly retrograding. This will likely promote hot and humid conditions Sunday through much of the following week.

Some uncertainty remains on exactly how hot temperatures will get given high dewpoints in the 70s, but highs approaching the low 90s appear increasingly likely by early next week. These temperatures combined with dewpoints in the 70s could lead to potentially dangerous heat indices approaching Advisory criteria.

AVIATION (18Z TAF Issuance)

Issued at 128 PM EDT Tue Jun 23 2026

Impacts:

- None

Discussion:

VFR conditions are expected through the period. Northerly winds to around 10kts later today will diminish to 5kts or less tonight. Patchy fog is possible towards daybreak Wednesday in spots, but confidence is too low to mention in the forecast at this time.

IND WATCHES/WARNINGS/ADVISORIES

None.