textproduct: Indianapolis

KEY MESSAGES

- Increasing clouds tonight and not as cold. Warmer on Tuesday and Wednesday.

- Rain chances are expected Tuesday night through Wednesday, transitioning to snow showers at times Wednesday evening through Friday

- Arctic outbreak expected this weekend with low temperatures in the single digits and potentially dangerous sub-zero wind chills

SHORT TERM (This evening through Tuesday)

Issued at 328 PM EST Mon Dec 8 2025

Surface analysis early this afternoon shows a broad area of high pressure stretching from the Great Lakes across IL to OK and TX. GOES16 shows some stratus still lingering over southern Indiana and the Ohio River, while the Central and northern parts of Indiana were under mainly clear skies. A few cirrus were found there due to the quick flow aloft. Aloft, quick northwest flow was in place aloft and a weak shortwave over EKY and OH was exiting quickly. Temperatures have risen to the upper 20s.

Tonight...

Models suggest the large surface high pressure system to the west will push across and east of Indiana tonight. This will allow the mostly clear skies as seen across Indiana as well as upstream to reside across the state through much of the evening. Overnight, warm air advection is expected to begin and models suggest a mid level cloud deck passing through the night. Forecast soundings show lower levels remaining very dry and overall forcing is limited, thus precipitation is not a concern. Thus mostly clear this evening with increasing clouds overnight. Given the expected cloud cover and warm air advection, lows should be slightly warmer, reaching mainly the lower and middle 20s.

Tuesday...

Models on Tuesday continue to suggest a quick northwest flow in place aloft, streaming from western Canada across the northern plains and into Indiana and the Ohio Valley. Little in the way of forcing dynamics appears present, so just some mid and high clouds passing within the quick flow aloft are expected. Within the lower levels, low pressure moving through the western Great lakes is expected to provide SSW surface flow to Indiana and continued warm air advection. Forecast soundings show dry air within the lower levels along with saturation aloft. This will lead to just partly to mostly cloudy skies. Given our southwest flow highs should reach into the lower 40s.

LONG TERM (Tuesday night through Monday)

Issued at 328 PM EST Mon Dec 8 2025

The long term period will start off near normal, and feel warmer than we have been experiencing, then quickly turn cold again with the potential for highs in the teens this weekend. There will also be a few chances for precipitation through the long term as a few upper waves pass by.

Central Indiana will be on the warm side of a weak system exiting the Great Lakes Wednesday, allowing highs in the 40s. Light precipitation is expected with this system mainly across the NE half of the forecast area; should fall mainly as rain, but some snow mixing in will be possible. Winds will also likely be a factor due to tight gradients around the surface low. At this time, sustained winds around 20 mph and gusts in excess of 30 mph are likely, which should start during the early morning hours Wednesday and last through the afternoon.

Behind the initial system, temperatures will again turn colder with the return of generally NW flow. Models show additional passing waves for the end of the week into the weekend that each have the potential for light snow as it doesn't take much energy to produce snow at colder temps. By Saturday and Sunday, highs in the teens and lows in the single digits will be possible for parts of the forecast area. Confidence is high in the well below normal temperatures but just how cold it will be this weekend is still unknown as models keep going back and forth on the spatial extent of the surge of arctic air this weekend. It does appear that somewhere nearby will likely be the furthest reach of the highs being in the teens. In our favor, the snow pack will likely melt away midweek with the warmer temperatures, so that could make it harder for the extreme cold to be realized. Either way, apparent temperatures this weekend will range from around -10 to near 0 so bundle up if you must spend time outside.

AVIATION (18Z TAF Issuance)

Issued at 1206 PM EST Mon Dec 8 2025

Impacts:

- Mainly VFR Conditions this TAF period.

- Brief MVFR Cigs possible at BMG through 20Z. Discussion:

GOES19 shows lingering stratus across southern Indiana impacting BMG. Elsewhere skies were mostly clear with only a few passing CI present.

Strong surface high pressure will drift across the TAF sites this afternoon and evening, leading to continued VFR conditions amid subsidence.

Overnight, the high will drift east of Indiana and warm air advection will begin. This will allow for the advancement of some mid level clouds across the TAF sites as surface winds become southerly.

On Tuesday, mid level clouds will still linger along with VFR conditions, however a tightening surface gradient across the area will allow for some wind gusts near 20 knts after daybreak on Tuesday.

IND WATCHES/WARNINGS/ADVISORIES

None.