textproduct: Indianapolis

KEY MESSAGES

- Snow showers ending this morning.

- Wind chills near zero this morning.

- Light snow likely late tonight into early Wednesday with up to an inch possible.

- Above normal temperatures return late week with highs in the 70s possible Friday and Saturday.

FORECAST UPDATE

Issued at 920 AM EDT Tue Mar 17 2026

Pesky light snow showers and flurries continue this morning but the end is in sight with the back edge of the flurries now progressing through the northwest half of the forecast area. It has been a bitterly cold start to this St. Patrick's Day with teens and wind chills in the single digits currently across central Indiana at 13Z.

A final upper level wave was moving across the area this morning with snow showers and flurries ending once it passes over the next few hours. Snow will decrease visibilities in spots but overall impacts will be minimal at best with no additional accumulation anticipated. A surface ridge will build in briefly for this afternoon with the potential for some sunshine before mid and high level clouds quickly expand back across the region this evening in advance of a fast moving clipper. W/NW winds remain sustained at 10- 15mph this morning but gusts have largely fallen back as the surface pressure gradient has weakened.

Temperatures will be nearly 25 degrees below normal today. The forecast high of 28 for Indianapolis would place this as a top 10 coldest St. Patrick's Day and the coldest March 17 in 85 years. Zone and grid updates out.

SHORT TERM (Today and tonight)

Issued at 244 AM EDT Tue Mar 17 2026

Scattered snow showers continue across central Indiana early this morning, with cyclonic flow persisting. Some upper energy is moving through the upper trough that is over the area, which is aiding forcing. Will keep isolated to scattered snow showers around through the pre-12Z time frame.

After 12Z, a weak surface trough will impact mainly eastern portions of the area before it exits mid-morning. Will have some low PoPs to account for any snow showers generated by this. No accumulation is expected.

Some of the lower clouds will break up by afternoon, but high and mid clouds will quickly increase later this afternoon ahead of the next system. Will keep skies partly to mostly cloudy this afternoon. Temperatures will only peak in the upper 20s to around 30 degrees. If the high at Indy remains under 30 degrees, it will be the coldest St Patrick's Day high temperature since 1941.

The evening will be quiet with thickening clouds, but snow chances will move in overnight with a clipper system. The surface reflection will be weak, but aloft some decent isentropic lift will move through.

Snow that develops from the lift will initially fight dry lower levels, but feel that there is enough forcing and moisture to overcome it by later in the night. Will raise guidance PoPs and go high end chance to low end likely categories for PoPs most areas overnight.

Thanks in part to the dry air, snowfall amounts should remain around an inch or less. Clouds and southerly winds will keep temperatures in the lower 20s for lows.

LONG TERM (Wednesday through Monday)

Issued at 244 AM EDT Tue Mar 17 2026

Wednesday...

Light snow from the clipper system may linger in the morning, so will keep some low PoPs going then. Otherwise, warm advection will bring temperatures in the 40s to lower 50s, melting any snow from earlier in the day.

Thursday through Saturday...

A large upper ridge will build over the western CONUS, with central Indiana remaining near the eastern edge. An upper wave will ride the edge of the ridge and bring some rain chances to the area on Thursday.

The ridge increase its influence some Friday and Saturday, which will allow warmer temperatures to return to the area. Some uncertainty remains in how warm it will get, with the ECMWF showing highs well into the 70s by Saturday, with others keeping readings around 70.

Sunday and beyond...

The upper ridge will get flattened some for early next week, which will allow colder air to return by Monday and Tuesday. Questions remain on just how cool it will get, but for now will keep readings a little below normal. Low chances for rain may return around Tuesday.

AVIATION (12Z TAF Issuance)

Issued at 721 AM EDT Tue Mar 17 2026

Impacts:

- Possible MVFR through 13Z-14Z in lingering -SHSN at KIND/KLAF... with high-MVFR likely continuing through 16Z at KLAF - West-northwest winds gusting to 17-20KT, diminishing this morning - Period of -SN late tonight with MVFR/low-VFR after 06Z-09Z

Discussion:

VFR conditions to prevail through most of the TAF period, following brief/isolated MVFR this morning in any lingering -SHSN through 14Z and/or at KLAF. West-northwest winds gusting to 17-20KT through 14Z- 16Z...with flow finally diminishing later this afternoon while backing to southwest by 00Z amid building surface ridging.

Winds to increase again later tonight as smaller disturbance approaches from Illinois...with CIGs falling to low-VFR/high-MVFR amid period of -SN that should bring MVFR/possibly brief IFR VIS at KIND/KLAF after 06Z.

IND WATCHES/WARNINGS/ADVISORIES

None.