textproduct: Indianapolis

KEY MESSAGES

- A very isolated shower or storm possible this afternoon.

- Cooler and less humid weather expected through Tuesday.

- The next best chance for rain will be Wednesday Night through Thursday.

DISCUSSION (This evening through Saturday)

Issued at 138 PM EDT Sat Aug 22 2026

Surface analysis early this afternoon shows broad low pressure in place over Ontario. A weak trough within this flow has pushed east of Indiana into Ohio, and westerly flow was in place. Some SCT-BKN CU had developed over Central Indiana and was quickly pushing east. Aloft, strong ridging was in place over the Rockies, resulting in lee side subsidence spilling across the northern plains and into the Ohio Valley on NW flow. Dew points across Central Indiana were mainly in the mid 60s and skies were clear over IL and IA, building toward Indiana.

Tonight and Sunday...

Upper ridging is expected to build east tonight and Sunday toward the upper midwest. This will keep NW flow in place across Indiana and allow subsidence to continue to build across our region. Strong surface high pressure will build across the Great Lakes and Ohio Valley. This will result in a mostly clear night and a mostly sunny Sunday. Highs will reach the upper 70s to around 80 on Sunday.

Monday...

Another pleasant late summer day will be in place on Monday, as ridging aloft continues to be in place over the upper midwest, allowing NW flow to continue to flow across Indiana with subsidence. Models suggest strong surface high pressure in place, stretching from Ontario to the deep south. Forecast soundings remain very dry during this period, thus another mostly sunny/partly cloudy day will be expected with highs in the lower 80s.

Tuesday through Saturday...

The upper pattern for much of the latter parts of the forecast will remain consistently from the NW. Stronger ridging aloft over the western CONUS looks to continue this ongoing NW flow across the upper midwest and into the Ohio Valley. An exception within this pattern will be on Thursday as an upper trough within the NW flows will push through the Great Lakes and Ohio Valley, providing some upper support. This feature will push a cold front across Central Indiana on Thursday, resulting in our best chances of the week for some light precipitation. Otherwise, surface high pressure due to the lee side subsidence aloft will continue to be dominate on Tuesday-Wednesday and again on Friday and Saturday. Expect temperatures to remain at or slightly below seasonal normals.

AVIATION (00Z TAF Issuance)

Issued at 738 PM EDT Sat Aug 22 2026

Impacts:

- VCSH possible through 01Z at KHUF - Low chance for brief fog at outlying terminals late tonight

Discussion:

Mainly VFR conditions to continue across central Indiana through Sunday evening as Canadian surface high pressure advances from the Dakotas to the Midwest. Cannot rule out a stray narrow downpour in the vicinity of KLAF or west of KHUF through 01Z this evening, but confidence only high enough to include at KHUF. Otherwise, sustained winds to fall below 7KT at outlying terminals by 01Z... with west-northwest flow becoming light, if not variable by 06Z.

Fog/BR is possible at the outlying sites late tonight under mostly clear skies and low dew point depressions amid cooler conditions. Mainly FEW/SCT decks expected Sunday amid light to moderate northwest breezes that will gust up to 13-17KT by late afternoon, especially at KLAF/KIND.

IND WATCHES/WARNINGS/ADVISORIES

None.