textproduct: Indianapolis

KEY MESSAGES

- Drier and cooler weather through Tuesday

- Freeze Warning in effect for northern half of central Indiana late tonight into Tuesday morning, frost development possible further south though confidence is limited

- Warming trend begins Wednesday and continues through next weekend

- Isolated to scattered rain chances return Thursday onward, which may bring receding rivers back into flood in some areas

SHORT TERM (This evening through Thursday)

Issued at 252 PM EDT Mon Apr 6 2026

Mostly quiet weather conditions are expected through the middle of this week under the influence of a Canadian surface high. Winds are currently gusting between 20-30 mph due to deep mixing and sunny skies ahead of the building surface high. Look for these gusts to diminish towards or shortly after sunset once mixing is cutoff. Cooler conditions will continue through Tuesday thanks to cold air advection before the high pressure then shifts eastward allowing temperatures to quickly warm up. Highs in the mid 40s to low 50s Tuesday should warm well into the 60s by Wednesday and possibly near 70F for far SW counties.

A Freeze Warning is in effect late tonight into Tuesday for the northeast half of central IN, from 2 to 10AM Tuesday. as temperatures at or below freezing are likely. The Freeze Warning does include the Indianapolis metro, but nearby surrounding areas could remain above freezing due to urban heat island effects. Frost development is possible further south, but there are a few limiting factors. Winds remaining slightly elevated, increasing clouds late overnight, and relatively marginal temperatures leads to lower confidence on frost potential. Some patchy frost still appears possible and more widespread frost formation cannot be ruled out if radiational cooling conditions become more favorable.

Make sure to cover any sensitive outdoor plants, even those not included in the Freeze warning due to some potential for frost. There is additional frost/freeze potential Tuesday night as lows will be in the low-mid 30s. The freeze potential is mainly confined to far eastern counties where temperatures could fall to 29-32 degrees. Winds remaining slightly elevated and additional clouds moving in overnight limits confidence for the frost/freeze potential once again.

An approaching system Thursday will promote breezy conditions. Dry weather should persist due to lingering subsidence induced dry air across the area. Rain chances return later in the week with more details regarding this in the long term discussion.

LONG TERM (Thursday night through Monday)

Issued at 252 PM EDT Mon Apr 6 2026

Expectation for late this week into the weekend remains a return to above normal temperatures and a potential return to active weather.

The strong Canadian high will be off the east coast by 00Z Friday, with a northern stream low near James Bay and moving rapidly eastward. An elongated cold front stretching from this low back to the central high Plains will stall somewhere near the region late week and may produce multiple opportunities for convection, though model disagreement precludes more than chance PoPs. Potential will exist for multiple rounds of precipitation, which could prolong or exacerbate ongoing flooding on main stem rivers given antecedent conditions as a result of the wet weather in recent weeks. Hydrologic ensembles do show renewed river rises next weekend in response to this potential rainfall, though a mostly dry week will help to hopefully blunt these impacts a bit.

There is little to indicate significant severe threats during the latter portion of the forecast, and this is backed up by experimental machine learning guidance. That said, week two outlooks continue to indicate enhanced likelihood of warmer than normal and above normal precipitation conditions, thus we may well be back in an active pattern for mid to late April.

AVIATION (18Z TAF Issuance)

Issued at 142 PM EDT Mon Apr 6 2026

Impacts:

- Wind gusts 20-27KT from 300-310 degrees through 00Z this evening

Discussion:

Deep PBL mixing and a passing front earlier in the day will continue promoting strong winds with sustained winds peaking at 15-19KT and gusts as high as 20-27KT through the afternoon. Winds and gusts will subside after sunset, but remain slightly elevated across northern portions of the area.

A few fair weather cu and thin high clouds will be possible at the sites today, though skies should remain mostly clear. A slow increase in clouds can be expected by late tonight.

IND WATCHES/WARNINGS/ADVISORIES

Freeze Warning from 2 AM to 10 AM EDT Tuesday for INZ021-028>031- 035>049-054>057-065.