textproduct: Indianapolis

KEY MESSAGES

- Generally dry Tuesday and Wednesday, better chances for showers and storms late Thursday into the weekend

FORECAST UPDATE

Issued at 919 PM EDT Mon Jul 6 2026

Surface high pressure and associated subsidence over the upper midwest is expected to sag southward across Indiana overnight and into Tuesday. Radar this evening shows diurnal showers have continued to dissipate as evening cooling has been ongoing. Water Vapor imagery still shows a warm and humid air mass in place across Indiana and points to the southwest amid a large and wide plume of gulf moisture.

Overnight, little available forcing will be present to drive any precip, as high pressure builds from the north. HRRR suggests the arrival of some cloud cover overnight. Given the very moist column across the area and the dew points remaining in the upper 60s to around 70, dew point depressions will be small overnight. Thus clouds and fog development will be expected late overnight as RH's approach saturation. Overall, ongoing forecast remains in good shape.

DISCUSSION (This Evening through Monday)

Issued at 233 PM EDT Mon Jul 6 2026

A humid airmass remains over the Ohio Valley with continued risks for isolated to scattered convection through this evening as an upper wave slowly drifts through. Upper level ridging will briefly reestablish as the wave aloft and deeper moisture shift south Tuesday and Wednesday. A cold front will move into the region and become nearly stationary by late Thursday...bringing another period of unsettled weather into the weekend.

This Afternoon through Wednesday Night

Stratus has fully mixed out into a cu field this afternoon with isolated showers drifting south to the north and west of the Indy metro. 18Z temperatures ranged from the upper 70s to the mid 80s.

The back side of the upper wave that has been parked over the region will drift south through the rest of the day and interact with a weakly unstable airmass present. Convection has been shallow in nature but additional heating over the next few hours should lead to a subtle uptick in coverage through late day focused especially over the eastern half of the forecast area. Any stronger cell will carry a threat for locally gusty winds as cores collapse...but the slow storm motion supports torrential rainfall as the primary threat from convection through the evening.

Any lingering showers or storms will diminish near sunset with quiet yet muggy conditions overnight. There remains potential for stratus to advect back into the region from the northeast in the predawn hours Tuesday...but the expansion of drier air from the north should keep stratus from becoming as widespread as it has the last two mornings. Weak ridging at the surface and aloft will expand across central Indiana Tuesday...forcing the convective threat closer to the Ohio River during the afternoon. With no appreciable forcing aloft and a largely dry column...have removed any mention of precip on Tuesday. There will be diurnal cu developing for the afternoon but that should even shift south late day as weak subsidence advects in from the Great Lakes.

The high will shift east and wash out on Wednesday but subtle surface ridging lingers which should keep most of the forecast area dry. The only exception will be over southern portions of the forecast areas as the axis of deeper moisture near the Ohio River lifts back north and interacts with a weakness in the mid level flow. Scattered convection will be possible largely south of a Sullivan-Bloomington-Columbus line mid to late afternoon.

With increasing sunshine for Tuesday and Wednesday...expect temperatures will recover back into the mid 80s for most of central Indiana.

Thursday Through Monday

The primary feature for the extended will be a cold front drifting south into the Ohio Valley on Thursday and becoming quasi-stationary as it bumps into the flat upper level ridge to the south. With the upper level flow transitioning to northwest as the core of the heat ridge retrogrades into the Intermountain West...there is increasing potential for convective clusters to track across parts of the region Thursday night into Saturday as individual perturbations aloft interact with the quasi-staionary frontal boundary.

Detail on placement of the boundary and primary timing of convective impacts remains inconclusive at this early stage. No strong signals are present for organized severe weather at this time but convection will likely carry a risk for damaging winds/microbursts with any stronger cells. Heavy rainfall and flooding will again be primary concerns with a deeply saturated airmass highlighted by PWATS approaching 2 inches.

Temperatures will largely hover near normal for much of the extended with highs in the 80s. Mid to upper 80s on Thursday will cool through the weekend. It now appears that a cooler drier airmass may remain bottled up to the north late weekend into early next week as the broad upper level ridge will shift back east towards the Mississippi Valley. This would support temperatures returning to near to above normal levels.

AVIATION (06Z TAF Issuance)

Issued at 1202 AM EDT Tue Jul 7 2026

Impacts:

- VFR early overnight.

- MVFR possible early morning...in patchy fog and low ceilings.

- VFR after daytime heating resumes.

Discussion:

Only a few sct high clouds were found on GOES19 across central Indiana late this evening, resulting in VFR conditions.

Lower stratus and fog may is expected to arrive overnight again. High dew points and low dew point depressions along light winds will be favorable for MVFR fog development near diurnal minimums. Any Stratus/Fog will mix out Tuesday morning as drier air advances into the region from the north, leading to a return to VFR.

BKN VFR cigs due to diurnal CU is expected on Tuesday afternoon, with clearing once again during the evening as daytime heating is lost.

IND WATCHES/WARNINGS/ADVISORIES

None.