textproduct: Indianapolis

KEY MESSAGES

- Below normal temps to continue through the weekend with frost possible again tonight

- Milder but still largely below normal for the upcoming week, with multiple chances for rain; heavy rain possible at times

FORECAST UPDATE

Issued at 934 PM EDT Sat May 2 2026

No major changes needed to the forecast with conditions generally evolving as expected. The main focus continues to be on the expected frost tonight with models generally remaining in line with earlier runs. A couple runs such as the WRF-ARW are running a few degrees cooler with the potential for frost to the west of the current Advisory area, but this model often overdoes radiational cooling. With the winds becoming more southwesterly during the overnight, modest moisture advection and at least some cirrus moving in from the northwest should keep frost mostly limited to the current area covered by headlines.

DISCUSSION (This evening through Saturday)

Issued at 312 PM EDT Sat May 2 2026

A relatively chilly start to the forecast period with NW flow aloft. Tonight will again see lows in the 30s and with mostly clear skies and light winds, there is another chance for frost over most of central Indiana.

The start of the new week will see multiple chances for rain as some waves move through and then a cold front Tuesday. Outside of the rain, wind gusts of 25 to 30 mph are expected to mix down, mainly during the afternoon hours. Late Monday into the overnight hours, thunderstorms ahead of the front are possible with a marginal risk of severe weather as cool temperatures aloft could help increase lapse rates and instability. Hail and gusty winds will be the main threat. Best chances for rain come as the front itself gets closer and approaches from the NW, so Monday night throughout the day Tuesday. Rain could continue to linger into Wednesday. Around half an inch, possibly up to an inch in some spots, is expected with this system.

Along and behind the front will again see below normal temperatures for mid to late week. Lows for Wednesday and Thursday nights are forecast to be in the low 40s but the potential to dip into the 30s can't yet be ruled out.

An upper wave late week will again lead to slight precipitation chances but confidence is low at this point.

AVIATION (00Z TAF Issuance)

Issued at 652 PM EDT Sat May 2 2026

Impacts:

- Wind shift from the northwest to southwest towards 02Z - Southwesterly gusts of 25kts tomorrow afternoon

Discussion:

Diurnally driven cu will gradually continue to dissipate over the next couple of hours leaving only a few passing cirrus clouds. Winds will shift from the northwest to southwest towards 02Z but will remain light through 16Z when gusts up to 25 kts returns. Clouds will also gradually begin to increase through the daytime hours tomorrow with a low-end threat for a few showers at LAF and IND towards 20Z.

IND WATCHES/WARNINGS/ADVISORIES

Frost Advisory from 1 AM to 9 AM EDT Sunday for INZ030-031- 037>042-046>049-054>057-062>065-070>072.