textproduct: Indianapolis

KEY MESSAGES

- Numerous showers and isolated thunderstorms this afternoon into tonight.

- Additional chances for precipitation late Saturday night into Sunday and again towards mid week

- Milder temperatures Saturday with highs in the 70s before slight cooldown late weekend into next week

DISCUSSION (This evening through Friday)

Issued at 215 PM EDT Fri May 8 2026

This afternoon through Saturday...

Mostly quiet weather conditions are ongoing across much of central Indiana as weak surface ridging remains in place. Current radar/satellite imagery does show an extensive area of clouds to the west with precipitation now moving into northwestern counties. This is associated with an approaching shortwave which will support numerous showers and possibly isolated thunderstorms later today into tonight. Severe weather is not expected due to weak instability, but a strong sub-severe storm cannot be completely ruled out if sufficient destabilization occurs given strong flow aloft.

Localized flooding appears to be a slightly greater threat into the overnight hours. While the environment does not support efficient rainfall rates, there is some concern for training due to the weak boundary slowly progressing southward. Latest CAMs suggest the potential for a corridor of 0.5 to 1.5 inches of rain near or south of I-70. These rainfall amounts on top off recent rainfall earlier in the week could lead to minor localized flooding.

Precipitation is expected to gradually clear out from NW to SE during the overnight as the aforementioned system and weak boundary move out. Increasing heights aloft along with weak surface ridging building in on Saturday will allow for quiet weather conditions. That said, a stray shower cannot be ruled out across northeastern counties. Breezy conditions are expected into the afternoon hours due to diurnal mixing into a modest LLJ. Warm air advection will allow temperatures to warm into Saturday with highs in the 70s.

Saturday night through Sunday...

Rain chances return to the forecast late Saturday night into Sunday following another subtle wave moving in. The subtle wave and an associated cold front should promote isolated to scattered showers. Diverging model solutions limits forecast confidence, but the greatest precipitation chances are late Saturday night when the cold front moves through. Cold air advection behind the departing system will then advect cooler-drier air across central Indiana. Isolated light showers may linger into Sunday, mainly across south-central IN. Expect cooler temperatures into the 60s again on Sunday.

Sunday night onward...

Quiet weather conditions are likely Sunday night through Monday with most guidance depicting strong high pressure building in. Rain chances return once again on Tuesday ahead of another low pressure system. Coverage of precipitation and overall QPF amounts remain uncertain this far out. One of the main caveats is moisture return appears subtle ahead of the approaching system. An amplified shortwave should promote surface cyclogenesis north of the area so light precipitation does appear likely for at least parts of central Indiana. This system is expected to depart on Wednesday supporting drier conditions. Look for temperatures to gradually moderate towards the middle of next week.

AVIATION (00Z TAF Issuance)

Issued at 801 PM EDT Fri May 8 2026

Impacts:

- Rain throughout the evening, to around 07z - MVFR or worse CIG after 04Z, through 12Z - Fog possible after rain ends, especially HUF and LAF - Wind gusts to 20kt Saturday afternoon

Discussion:

Rain has moved into central Indiana with MVFR visibilities at times. The primary axis of rainfall will be from HUF, IND, and BMG continuing through about 06z, with only scattered showers possible at LAF. A rumble or two of thunder is possible, with the best chance at BMG.

After the rain ends, light winds along with clearing skies could lead to patchy fog formation. This depends on where the heaviest rainfall occurs, however, and how fast skies clear after it ends. For now, tempo groups have been included at HUF and LAF for reduced visibility.

MVFR/IFR ceilings likely develop over night along with potential fog. These conditions could persist into the morning hours on Saturday. Clearing is expected with a return to VFR by 16z.

IND WATCHES/WARNINGS/ADVISORIES

None.