textproduct: Indianapolis

KEY MESSAGES

- Active pattern this week with near daily chances for showers and storms

- Severe weather is a possibility later today and Tuesday focused mainly across the northwest half of central Indiana. Additional threats for strong to severe storms Wednesday and Saturday

- Warm temperatures expected through Saturday with multiple days in the lower to mid 80s. Record temperatures are possible

FORECAST UPDATE

Issued at 948 AM EDT Mon Apr 13 2026

Isolated light showers continue across the far southern forecast area this morning. Skies were partly to mostly cloudy, and temperatures were around 70 at most locations.

Some weak forcing may continue across the southern quarter to third of the forecast area into early afternoon, so kept some slight chance PoPs there. Otherwise, chances for rain look very low until mid afternoon to early evening.

An upper wave currently generating some convection across Missouri/far western Illinois will move northeast and may generate more convection as instability increases this afternoon. The bulk of the convection would remain north of central Indiana, but some may get into the northern portion of the area. There will be enough instability and shear for isolated severe storms with damaging winds and large hail across the far northern portions of the area.

Partly to mostly cloudy skies look to continue today, but there will be enough sun to bring temperatures to around 80. Made no significant changes to forecast highs, but will continue to monitor clouds and adjust temperatures if needed.

DISCUSSION (Today through Sunday)

Issued at 300 AM EDT Mon Apr 13 2026

Scattered showers have been extremely efficient early this morning in pulling strong wind gusts briefly to the surface. Multiple observations of 40 to 50 mph winds have been seen across the northern half of the forecast area since late last evening with even a higher gust to 65mph at KIND around 0530Z. Temperatures remained warm with 06Z readings generally in the upper 60s to mid 70s.

Today through Tuesday

The ongoing showers are associated with a potent upper level wave traversing the region this morning. The ACARS sounding at KIND continues to show an excellent setup for pulling the 50kt winds at 3kft agl to the surface with any showers as the presence of dry air within the boundary layer and a dry adiabatic flow up to about 700mb has produced an inverted V sounding. Over the most recent ACARS soundings the top level of the dry layer has been slowly falling and as of 06Z resided at around 800mb. Showers will impact the area for a couple more hours with ideal conditions for stronger gusts potentially in excess of 50mph at times. Freshened the SPS to highlight more recent observations and trends with the focus for strongest gusts shifting to the Indy metro and points northeast through about 08-0830Z.

The departure of the core of the low level jet to the east and a gradual top down moistening of the boundary layer will end the threat for the strongest gusts within the next couple hours but general wind gusts up to 25 to 30 mph will persist through much of the day. Moisture advection will arrive quickly on the heels of the departing showers and with it will come increasing instability which may be enough to generate additional isolated to scattered convection through daybreak prior to the back edge of the forcing aloft associated with the upper wave shifts away to the east. Much of the rest of the day through mid afternoon will be quiet with a blanket of stratus settling over much of the forecast area as a shallow moisture layer becomes trapped beneath an inversion. The arrival of subtle surface ridging later this afternoon will enable the deck to lift and mix out somewhat. Highs will again be near 80.

Scattered convection may redevelop by late day but should be largely focused north of the forecast area in closer proximity to the warm front across the lower Great Lakes. Any convection that does fire into the evening over northern Indiana will carry a severe risk as a narrow band of moderate instability aligns with a rapid increase in shear and SRH within the 0-3km layer. Some of this convection may slip into far northern portions of the forecast area during the evening but the presence of a cap around 750mb should be sufficient to limit most convective development this far south. Much of the rest of the night will be quiet under a muggy airmass with continued breezy southwest winds. Lows will only fall into the mid and upper 60s.

Most of Tuesday will be warm and humid with temperatures likely to threaten record highs in the afternoon as readings warm into the lower and mid 80s. A surface wave tracking along the frontal boundary into the upper Midwest will serve as a trigger for robust convective development in the afternoon that will likely migrate E/SE Tuesday evening and night into a modestly unstable airmass with steep mid level lapse rates across the region. Severe weather is a threat focused mainly across the northwest half of the forecast area during the evening as the frontal boundary drifts into northern Indiana and a nocturnal low level jet becomes established. Damaging winds will be the primary threat but all hazards are in play. Locally heavy rainfall will be possible as well although the recent stretch of drier conditions over the last 7 to 10 days will limit any flooding concerns. Showers and storms will continue through the night and likely be ongoing at daybreak Wednesday across far northern portions of the forecast area.

Wednesday through Sunday

Active weather will continue into the weekend as the aforementioned frontal boundary remains north of the region through late week. A stronger surface low will track into the upper Midwest Saturday and pull the boundary through the area as a cold front. Cooler and drier weather will follow for the second half of the weekend.

The front will nudge itself closer to the forecast area Wednesday as low pressure occludes over the upper Mississippi Valley with a more widespread convective threat for the entire area that will persist into Thursday. A few storms may be severe yet again with modest instability across the Ohio Valley especially Wednesday afternoon and evening. The boundary should retreat back north Thursday night into Friday with chances for rain and storms lowering. Signs are pointing towards another risk for severe weather Saturday as a cold front sweeps across the Ohio Valley. Temperatures from the upper 70s to mid 80s will be common this week with Friday likely to be the warmest day.

Cooler and drier conditions are expected for Sunday and Monday as high pressure builds in behind the front. The cooldown appears brief as upper level ridging should return to the Ohio Valley by next Tuesday and Wednesday.

AVIATION (12Z TAF Issuance)

Issued at 540 AM EDT Mon Apr 13 2026

Impacts:

- MVFR ceilings expected later this morning through mid afternoon - Wind gusts up to 20 to 25kts likely through this evening - Scattered convection may impact KLAF this evening

Discussion:

An upper level wave is moving off to the east early this morning but enough forcing aloft lingers as instability and low level moisture increases that scattered convection may redevelop mainly near and south of I-70 over the next few hours. By mid morning moisture will become trapped beneath an inversion leading to an expansion of MVFR stratus into the area for a few hours into the mid afternoon before the deck mixes out and lifts.

Southwest winds will remain breezy throughout the day with gusts peaking at near 25kts at times through tonight. There is potential for convection to develop over north central Indiana this evening in closer proximity to a warm front over the lower Great Lakes. Have inserted a VCSH mention for a few hours during the evening at KLAF but confidence remains low on potential impacts.

CLIMATE

Issued at 300 AM EDT Mon Apr 13 2026

Within the setup described in the discussion above, near record temperatures are possible at times this week, mainly Tuesday, and Friday. Whether readings get close depends on sky cover and any rain staying away, which keeps confidence lower at this time.

Current deterministic model runs are cooler than the records, but the potential exists to get within a few degrees if everything lines up. On Tuesday April 14, Indy's record high is 85, set in 1883. On Friday April 17, Indy's record high is 87, set in 1896.

Record high minimum temperatures are also in play at times given the warm and relatively humid airmass. The first opportunity for this comes Monday, when the record high minimum at Indy is 63, set in 2014 and tied in 2018. At the moment, the forecast is for tying that number.

IND WATCHES/WARNINGS/ADVISORIES

None.