Storm risk Sunday before a sharp cooldown early next week | Mar. 21, 2026

TONIGHT

A very mild night is on tap for Indianapolis with mostly clear skies and a low around 60. South southwest wind stays going near 5 to 10 mph, so the air should not cool off much at all overnight. Impacts are minimal, with good travel conditions and no weather hazards beyond the unusual warmth for late March. 

TOMORROW

Sunday is the attention-grabber in this run. The day starts warm and mostly dry, then clouds increase with a chance of rain developing during mid to late afternoon before a chance of thunderstorms arrives toward evening. Highs reach the lower 80s, and south southwest wind increases to around 10 to 15 mph with gusts near 25 mph. The main impact is late-day storm potential after a very usable daytime stretch. A few strong to severe storms cannot be ruled out, so any evening plans need a weather check before heading out. 

TOMORROW NIGHT

 The front comes through Sunday night with a chance of thunderstorms early, then a chance of plain rain for a time before things taper off. Temperatures crash hard by daybreak, falling to the upper 30s, and the wind flips north around 10 to 15 mph with gusts to 25 mph. The biggest impacts are the evening thunder risk, wet roads, and then a much colder feel by Monday morning. This is the one period in the forecast with a meaningful hazard signal, even though coverage does not look widespread enough to make it an all-night washout. 

MONDAY

Monday feels like a full reset after the weekend warmth. Skies turn mostly sunny, but highs only recover into the low 50s with a north wind around 10 mph and occasional gusts near 20 mph. It looks dry and bright, yet noticeably cooler, so the impact is mostly on comfort rather than travel or safety. 

MONDAY NIGHT

Monday night turns quiet and chilly with partly cloudy skies and lows in the mid 30s. North wind eases to around 5 mph. No major hazards are expected, but it will feel much more like early spring again after the warm weekend. 

TUESDAY

Tuesday trends a bit milder with mostly sunny skies and highs near 60. South southeast wind stays light around 5 mph. This looks like a low-impact day with decent outdoor conditions and no significant weather concerns. 

TUESDAY NIGHT

Clouds increase Tuesday night, but it still looks dry with lows in the lower 40s. South southeast wind holds around 5 mph. Impacts remain minimal, with only a slightly cooler and cloudier feel overnight. 

WEDNESDAY

Wednesday stays mostly cloudy and seasonably mild with highs in the mid 60s. Southeast wind runs around 5 to 10 mph. It is another fairly quiet day, though the thicker cloud cover keeps it from feeling as bright as Tuesday. 

WEDNESDAY NIGHT

By Wednesday night, a small rain chance returns with a slight chance of showers and even a thunderstorm after 2 a.m. Lows hold in the lower 50s with a south wind around 5 mph. Impacts look limited for now, but it is the next window to watch for unsettled weather.

7 DAY FORECAST

The overall pattern features one more spring surge, then a quick correction, then a gradual warm back up. Tonight stays very mild, Sunday pushes into the lower 80s with the only notable storm chance of the period arriving late day into Sunday night, and Monday snaps back into the low 50s with a brisk north wind. From there the forecast turns quieter, with highs near 60 Tuesday and the mid 60s Wednesday before the next low-end rain chance sneaks in Wednesday night and likely grows a bit more by Thursday.