textproduct: Indianapolis

KEY MESSAGES

- Slightly elevated fire weather danger on Friday due to low relative humidity and dry ground conditions

- Widespread rain expected Saturday night late into Sunday from tropical moisture remnants.

DISCUSSION (This evening through Thursday)

Issued at 153 PM EDT Thu Oct 8 2026

Surface analysis this afternoon shows strong high pressure stretching from MN to IN, building SE. The upper flow was dominated by northwest flow aloft, stretching from the Pacific NW across the northern plains to the Ohio Valley. Water Vapor showed a stream of high moisture within this flow reaching Central Indiana. This was not producing any precip within the region. Diurnal heating, mixing and ongoing subsidence has led to dew points to fall into the 40s.

Tonight and Friday...

Pleasant weather is expected tonight as the surface high pressure passes across Central Indiana before reaching the middle Atlantic States on Friday. Forecast soundings tonight and Friday show a dry column with unreachable convective temperatures. Thus expect continued mostly clear skies. Some high passing CI will be possible at times. Due to the low dew points, expect lows in the upper 40s tonight.

Some warm air advection is noted on Friday as the surface high drifts east and southerly flow develops within the lower levels. This will lead to warmer highs in the lower 80s.

Saturday...

Some elements of the weather pattern will begin to change on Saturday. The NW flow aloft is expected to transition to ridging over the Mississippi and Ohio valleys. This will steer any upper level moisture north of Indiana. Overall a dry day is expected. However as the day progresses high clouds from hurricane remnants will begin to arrive across Indiana from the south. This result will be increasing cloudiness, especially notable in the afternoon and evening. Highs should once again reach the lower 80s with little overall change with the lower level airmass.

Forecast soundings on Saturday night begin to saturate toward 12Z Sunday as cyclonic flow left from the hurricane arrives within the Ohio Valley. Chances for showers late on Saturday night will need to be included as forcing from this system arrives. Lows will only reach the upper 50s on Saturday night due to the arrival of a warmer and more humid air mass.

Sunday...

Hurricane remnants will be passing across Indiana on Sunday. Best moisture and forcing looks to impact the southern and eastern halves of Indiana. This will lead to a rainy end to the weekend, especially during the morning and early afternoon as the forcing dynamics pass. Dry air and easterly progression of the system are suggested to arrive by late Sunday afternoon and into Sunday night. This should bring an end to any rainfall.

Monday...

Some upper ridging and surface high pressure will bring quiet and warm weather to the area on Monday. Highs will reach around 80 to the lower 80s.

Tuesday onward...

It appears there will be enough influence from an upper trough moving through southern Canada to push a cold front through the area on Tuesday. Moisture looks to be limited so will only have some low PoPs.

Uncertainty remains on the details, but an upper trough across the western USA will create a surface low well northwest of central Indiana mid-week next week. An associated warm front will move into the area and could bring some rain Wednesday and Thursday. With the uncertainty will keep PoPs low.

Highs on Tuesday will reach around 80 before falling back into the lower and middle 70s Wednesday on the cool side of the front. Middle to upper 70s look likely on Thursday.

AVIATION (18Z TAF Issuance)

Issued at 1248 PM EDT Thu Oct 8 2026

Impacts:

- VFR conditions this TAF Period

Discussion:

High pressure centered over the northern plains will be drifting across Central Indiana during this TAF period. This will lead to clear skies and light winds with unlimited CIGS. Forecast soundings continue to indicate a dry column.

Expect winds to subside diurnally this evening before picking up again on Friday as heating and mixing resumes.

IND WATCHES/WARNINGS/ADVISORIES

None.