Area Forecast Discussion

KEY MESSAGES

- Rain and a few embedded thunderstorms tonight, with showers continuing on and off through the morning hours.

- Wind gusts between 20-30 mph possible at times.

- A return to more seasonable, cooler temperatures is expected late this week through early next week

DISCUSSION (Today through Tuesday)

Issued at 1241 AM EST Wed Nov 4 2026

A positively-tilted trough located over the Great Plains is slowly tilting more negatively this evening. At the surface, low pressure centered over Minnesota is lifting northward with a trailing cold front extending well southward through Iowa, Missouri, Arkansas, and through Texas. Surface low pressure is beginning to reform over eastern Kansas into southwest Iowa as the base of the trough gains negative tilt. This secondary low will then become the primary low overnight, lifting northward into Wisconsin.

Here in Indiana, the tightening pressure gradient from the low over Iowa will help drive a potent 40-50kt low-level jet northward tonight. Strong warm air advection is ongoing with temperatures near 70 as of 9pm. Surface winds have largely died down, compared to earlier, which is due to increasing boundary layer stability. ACARS soundings out of IND show a rather deep stable layer, roughly to 3km agl, which will inhibit downward momentum transfer for the time being. Soundings also show a rather dry column with substantial dryness in the mid and upper-levels. As such, buoyancy is almost non- existent in the current soundings.

Going forward, guidance is in good agreement showing greater moisture advection in a narrow band ahead of the approaching cold front. This will help improve the thermodynamic environment overnight from a convective standpoint. Nevertheless, poor lapse rates and a stable boundary layer will limit instability to under 500 J/Kg MUCAPE. Thunderstorms are still possible, however, due to limited CIN and sufficient large-scale forcing. Severe weather does not appear likely, again due to poor lapse rates and limited instability. Gusty winds are possible at least initially as rainfall encounters residual dry air.

Showers and embedded thunderstorms have entered our CWA form the southwest as of this writing (12am), progressing northeastward rapidly. High-resolution guidance shows a QLCS weakening it as it encounters the dry and stable pre-frontal environment. Gradually, as the column becomes saturated, heavier showers and embedded storms arrive later tonight and towards morning. Rainfall amounts between 0.25 and 0.75 inches will be most common, with locally heavier amounts possible further south and east.

Scattered showers may linger into the afternoon until the cold arrives around 18z. After that, westerly surface winds and mostly cloudy skies are anticipated. Highs today will likely occur before sunrise.

Thursday and Friday...

Thursday looks quiet ahead of an approaching upper trough and surface cold front. The trough and cold front will move through Thursday night into Friday. Moisture will be limited with the Gulf cut off. Will have some mainly slight chance PoPs on Friday, with the most coverage expected during the first half of the day.

Highs on Thursday will be in the lower to middle 60s, but Friday will see mainly upper 50s for highs as cooler air moves in behind the front.

Saturday onward...

Northwest flow will continue Saturday into early next week. An upper low moving through southeast Canada will bring another cold front on Sunday. Similar to Friday though, moisture will be very limited with the Gulf cut off again. Will go with a dry forecast through the entire period.

The cold front won't have much cold air behind it. Highs in the middle 50s on Saturday will gradually moderate to the lower and middle 60s by Tuesday. Lows will be near freezing for parts of the area Saturday and Sunday nights.

AVIATION (06Z TAF Issuance)

Issued at 1241 AM EST Wed Nov 4 2026

Impacts:

- LLWS from the south around 40kt through 08z.

- Surface wind gusts up to 25kt overnight

- Widespread showers expected late tonight into Wednesday morning

- MVFR ceilings developing after 06Z

Discussion:

Rain showers are beginning to enter central Indiana as of 06z along with lowering ceilings. MVFR conditions become likely within the first few hours of the TAF period. Rain may briefly reduce visibility at times through 12z. Rain showers persist on and off until a cold front arrives during the afternoon around 18z.

Additionally, a low-level jet around 40-50kt may lead to wind shear around 40kt early tonight. A LLWS group has been added to the TAFs to account for this. Surface winds have dropped to around 10kt out of the southeast. Wind speeds/gusts should pick up once rain showers arrive allowing for some of the low-level jet momentum to transfer downwards.

Surface winds to become west-southwesterly after the cold front passes through this afternoon. Gusts up to around 20kt remain possible behind the front with near-MVFR ceilings.

IND WATCHES / WARNINGS / ADVISORIES

None.