textproduct: Indianapolis

KEY MESSAGES

- Rain expected tonight through Tuesday night

- Turning colder beginning Wednesday into next weekend

- Watching Saturday into the following week for strong storm systems to bring rain, snow, and large temperature swings to Indiana

FORECAST UPDATE

Issued at 954 PM EST Mon Nov 24 2025

The forecast remains in good shape with only minor adjustments made to POPs. Latest KIND radar imagery depicts rain mainly confined to far NW portions of central Indiana at this time. This is where the strongest forcing from an approaching shortwave is overlapping with sufficient moisture. Expect rain coverage to continue increasing through the overnight as the shortwave moves in. Look for widespread precipitation by late tonight thanks to stronger mid-upper level forcing. Extensive cloud cover, rain, and southeasterly surface flow will help to limit diurnal cooling. Temperatures are only expected to cool a few degrees with lows ranging from the mid 40s to near 50F.

SHORT TERM (This evening through Tuesday)

Issued at 302 PM EST Mon Nov 24 2025

Mostly cloudy to cloudy conditions will persist through the remainder of the afternoon. Some weak lift may produce some sprinkles or light rain, mainly in the far southwest/west. Will keep some low PoPs there.

Tonight, an upper trough will approach the area from the west, and an area of surface low pressure will move into Illinois. A surface trough/warm front will move north into central Indiana. Upper and low level jets will also move into the area.

The low level jet will bring in additional moisture. The lift from the above features combined with the plentiful moisture will bring rain to central Indiana. Current timing of the most coverage of rain is overnight, when the low level jet kicks in. Will go high PoPs all areas. Instability remains south of the area, so will continue to not mention thunder.

Low temperatures will generally be in the 40s.

Stronger lift and deeper moisture will exit the area to the east during the morning as the upper trough and surface low exit to the east. Will have likely or higher PoPs early in the day over the eastern two-thirds of the area, with PoPs then diminishing from west to east during the morning.

Low level moisture will linger through Tuesday afternoon. There looks to be some weak lift in this layer, which should result in drizzle from time to time.

Warm advection should push temperatures into the middle 50s to near 60.

LONG TERM (Tuesday night through Monday)

Issued at 302 PM EST Mon Nov 24 2025

A significant pattern change is expected this week.

Synoptic analysis shows a progressive split flow pattern over the CONUS. Flow tends to diverge over the intermountain west before re- converging over the Midwest. A vort max within the southern jet axis is currently ejecting into the Plains, and will be the source for the rainfall expected tonight into tomorrow. This system is expected to strengthen substantially over the Great Lakes, driving a potent cold front southward on Wednesday. Deep troughing then takes hold over the eastern third of the CONUS which persists into the weekend.

Wednesday into Thursday

Of particular interest is Wednesday's cold front. This front will be the first stage of our pattern change, with scattered showers along the front itself and strong cold air advection and gusty winds behind it. Wednesday's highs likely peak before sunrise, falling continuously through the day. Combined with winds in the 20-30mph range, it will feel rather unpleasant. Additionally, some scattered flurries are possible Wednesday since cold air advection aloft will lead to some low-level instability.

Winds remain on the breezy side through Thanksgiving as a relatively tight MSLP gradient persists across the Midwest, though we can be thankful that it does not appear to be as windy as Wednesday. That may be of little consolation since highs may struggle to reach freezing. Wind chills into the 20s even during the afternoon appears likely.

Friday through Sunday

Troughing and cooler than average temperatures are expected to continue into the weekend. Simultaneously, a storm system is modeled to take shape out west as a shortwave trough comes ashore over the Pacific Northwest late Thursday. After that, the situation becomes tricky with guidance diverging considerably. A wide range of scenarios are possible, ranging from a warming trend with rain showers to continued cold with accumulating snowfall. The eventual outcome will be determined by how the western trough evolves.

The GFS, for instance, generally allows the trough to dig southward with slow progression eastward. This allows the system to lift northward later with broad warm flow ahead of it. This would bring about a warmer and rainier solution for much of Indiana, with perhaps some snow at onset or further north. On the contrary, the ECMWF/GEM take the shortwave and allow it to dive southeastward within the flow around the larger and retreating eastern trough. This would allow less in the way of warm air advection ahead of the system and thus lead to a snowier solution.

Taking a look at the various teleconnections we see a generally neutral trending negative PNA, with neutral AO/NAO. Negative PNA typically favors persistent western troughing / eastern ridging, which both the GEFS and EPS ensembles do show later in the forecast period. Unfortunately, this would mainly be after our potential storm system which occurs during the transition from troughing to ridging over the eastern US. Though that does point to a gradual warming trend after the weekend storm with a potentially active storm track remaining in place into December.

For now, both sets of guidance are in decent agreement showing an initial round of snow Friday night/early Saturday with the first push of warm air advection. Model uncertainty increases thereafter, though we'll maintain a slow transition to mainly rain until guidance comes into agreement on how strong and prolonged the warm air advection is. Stay tuned for updates.

AVIATION (06Z TAF Issuance)

Issued at 1239 AM EST Tue Nov 25 2025

Impacts:

- VFR deteriorating quickly in rain tonight to IFR/LIFR by 09Z

- LIFR/IFR continuing into Tuesday evening...as -SHRA taper to -DZ from west to east by midday

- Ceilings most likely improving to MVFR towards end of 24-hr TAF period

Discussion:

Upper short wave trough and weak surface low pressure crossing Midwest through Tuesday evening...will bring poor flying conditions from pre-dawn hours into at least early this evening. Low ceilings will lead IFR/LIFR conditions, with visibility likely falling to IFR at most TAF sites this morning. Rain will increase in coverage from southwest to northeast during overnight hours...then scatter out to -SHRA from west to east after 10Z...before tapering to -DZ around late morning to midday hours.

IFR to linger this afternoon, with low-MVFR not expected until at least late this evening. Additional showers are expected Tuesday evening as a cold front approaches the region. Southeast winds tonight will veer to south and then southwest on Tuesday.

IND WATCHES/WARNINGS/ADVISORIES

None.