textproduct: Indianapolis

KEY MESSAGES

- Breezy today with wind gusts of 30 to 40 mph this afternoon

- A Freeze Warning is in effect tonight into early Monday for the northern half of central Indiana

- A Frost Advisory continues early this morning for all of the area, with another Frost Advisory tonight for much of the southern half of central Indiana.

- Warming trend beginning on Tuesday

DISCUSSION (Today through Saturday)

Issued at 250 AM EDT Sun Apr 19 2026

Today and This Evening...

Clouds from the previous system have just about exited the forecast area to the east. Mostly clear skies will continue through the morning hours. Readings in the 30s with light winds will lead to frost, so continued the Frost Advisory as is.

This afternoon, an upper wave will move through the upper trough and bring a cold front into central Indiana. The system will not have much moisture to work with. However, very steep lapse rates combined with the forcing might just be enough to get a few isolated showers. Best of the limited moisture will be north, so will have some slight chance PoPs across the north half or so this afternoon.

The steep lapse rates will promote good mixing, which will bring down some of the stronger winds aloft. This will likely result in wind gusts peaking in the 30 to 40 mph range this afternoon. The inverted V soundings indicate the potential for higher gusts from any showers that do develop.

Wind gusts will end by early evening as mixing ends, and the shower threat will end then too as the front exits.

Overnight tonight through Monday night...

High pressure will build in overnight and Monday. This will bring mostly clear skies and keep temperatures below normal.

Cold advection will bring low temperatures in the lower to middle 30s across the area tonight. Diminishing winds with the high will also allow for frost formation. Given this, have upgraded the Freeze Watch to a Freeze Warning as well as issued a Frost Advisory for much of the remainder of the area.

Uncertainty is higher whether temperatures get to 32 in the southernmost counties of the Freeze Warning, but would rather err on the side of caution.

As the high slides east Monday night, increasing southerly winds will keep most areas in the upper 30s to middle 40s for lows.

Tuesday onward...

A cold front may bring a few showers or thunderstorms Tuesday night. Otherwise, better chances for rain will wait until around Friday when a larger upper trough and a cold front influence the area.

Above normal temperatures will rule Tuesday through Friday, then closer to normal readings return for next weekend behind the cold front.

AVIATION (06Z TAF Issuance)

Issued at 1258 AM EDT Sun Apr 19 2026

Impacts:

- Wind gusts near 30kt Sunday afternoon with potentially higher gusts

Discussion:

The large area of mid and high clouds will exit to the east of the sites by valid time, leaving mostly clear skies.

A cold front will move into the area this afternoon. Winds will become southwest by 12Z, then veer to west and northwest through the period as the front moves through. Stronger winds aloft will mix down, with gusts around 30kt expected this afternoon. If mixing gets higher than expected, higher gusts may occur.

Isolated showers will be with the front, but coverage will be too low to mention. VFR ceilings will develop with the front.

IND WATCHES/WARNINGS/ADVISORIES

Frost Advisory until 9 AM EDT this morning for INZ021-028>031- 035>049-051>057-060>065-067>072.

Freeze Warning from 2 AM to 9 AM EDT Monday for INZ021-028>031- 035>049-054>057.

Frost Advisory from 2 AM to 9 AM EDT Monday for INZ051>053- 060>065-070>072.