213 
FXUS63 KIND 210801
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
301 AM EST Fri Nov 21 2025

.KEY MESSAGES...

- Dense fog through mid morning focused mainly across the northern 
  half of central Indiana

- Rain will expand across the area from the southwest today

- Additional rainfall early next week with much cooler weather 
  likely post-Thanksgiving

&&

.SHORT TERM (Today and Tonight)...
Issued at 300 AM EST Fri Nov 21 2025

Continued dreary conditions can be expected through the period as a 
persistent subsidence inversion aloft and warm air advection beneath 
it allows a low-level stratus deck to remain in place. Latest 
observations show ceilings and visibilities have improved gradually 
through the day as temperatures have slowly warmed. Unfortunately, 
this improvement will only be short-lived as ceilings and 
visibilities drop again overnight. 

Latest guidance has trended drier overnight especially across the 
northern half of the area. Forecast soundings show the subsidence 
inversion strengthening over the north slightly with winds becoming 
very light or even calm at times. This and very small dewpoint 
depressions will quickly promote fog development into the overnight, 
potentially dense. Patchy drizzle is also possible thanks to 
marginal forcing. Guidance shows subsidence slowly increasing aloft 
overnight across the south as well. However, greater PBL moisture 
and slightly stronger forcing supports better chances for drizzle 
and the development of light showers. The higher chances for light 
precipitation over southern counties leads to lower confidence in 
coverage or duration of fog overnight. 

Model guidance depicts the aforementioned subsidence inversion 
weakening with increasing isentropic ascent during the day Friday. 
This will lead to greater coverage of showers as the day goes on. 
Showers should help clear out fog through the morning. Cannot rule 
out fog lingering through midday across the north if showers move in 
later than expected. Blended guidance has been far too warm with the 
stratus deck overhead which has limited the diurnal temperature 
swing significantly. High temperatures today and tomorrow were 
trended lower than the NBM. Look for lows to generally range from 
the mid 40s to near 50F tonight while highs Friday mostly remain in 
the low 50s.

&&

.LONG TERM (Saturday through Thursday)...
Issued at 300 AM EST Fri Nov 21 2025

Seasonably mild and dry weather is expected over the weekend as the 
recent quasistationary front is finally moved out of the region by 
the system expected to bring rain to the area today.

The next rainmaker for the area is the closed low currently over the 
West Coast, which will gradually shift northeastward and may phase 
with a northern stream upper level disturbance as both promote lee 
cyclogenesis over the central Plains, with the resultant surface low 
moving quickly into the Great Lakes early to mid next week. This 
system will bring another round of rain to the area as late Monday, 
with the most significant rain chances Monday night into early 
Tuesday.

Depending upon the intensity of the upper low/trough, there will be 
some low potential for lingering rain as late as Tuesday night into 
Wednesday, but these chances are far more uncertain at this point.

What is more certain is that a fairly substantial cooldown is likely 
for Thanksgiving and beyond, though the exact magnitude of the 
colder conditions remains to be seen. At the moment, highs in the 
30s and lows in the 20s and perhaps upper teens appear likely.

&&

.AVIATION (06Z TAF Issuance)...
Issued at 1216 AM EST Fri Nov 21 2025

Impacts:

- Widespread IFR/LIFR conditions through tonight
- Rain overspreading the terminals predawn hours through the morning

Discussion: 

Very poor flying conditions will continue through the duration of 
the forecast period as moisture remain trapped in the near surface 
layer beneath an inversion. Ceilings hovering early this morning at 
or below 500ft and expect that to continue along with the expansion 
of dense fog at times through and beyond daybreak. Rain will expand 
into the region first reaching KHUF and KBMG in the predawn hours 
then the other terminals through the morning. 

Widespread rain is expected to last into tonight with the potential 
for the heaviest rainfall at KBMG. The onset of rain should flush 
out the dense fog and may help bump up ceilings slightly during the 
day...but IFR and lower conditions will persist. Near calm winds 
through daybreak will shift to E/NE at 5-7kts this afternoon.


&&

.IND WATCHES/WARNINGS/ADVISORIES...
Dense Fog Advisory until 10 AM EST this morning for INZ021-
028>031-035>049-054>057.

&&

$$

SHORT TERM...Ryan
LONG TERM...Nield
AVIATION...Ryan

731 
FXUS63 KIND 210801
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
301 AM EST Fri Nov 21 2025

.KEY MESSAGES...

- Dense fog through mid morning focused mainly across the northern 
  half of central Indiana

- Rain will expand across the area from the southwest today

- Additional rainfall early next week with much cooler weather 
  likely post-Thanksgiving

&&

.SHORT TERM (Today and Tonight)...
Issued at 301 AM EST Fri Nov 21 2025

Dense fog with visibilities of 1/4-1/2SM has become prevalent across 
the northern half of the forecast area early this morning as 
moisture remains trapped within the near surface layer under a 
shallow inversion. 07Z temperatures had moved little from readings 
on Thursday in the mid and upper 40s.

The fog and low ceilings will persist as the primary concern for the 
next several hours past daybreak but the approach of low pressure 
currently over the central Plains will spread rain across much of 
the area through tonight.

Have expanded the Dense Fog Advisory to cover the northern half of 
the forecast area through 15Z based on obs and webcams. With near 
calm surface winds and model soundings showing no weakening of the 
shallow inversion...there is nothing available to offer a mixing 
component to the near surface layer through daybreak and potentially 
for a good chunk of the morning. The arrival of the broad area of 
rain to our southwest currently across the Ozarks east into the 
lower Ohio Valley will eventually serve as a catalyst to dissipating 
the dense fog but that will take some time as gradually stronger 
isentropic lift expands into the region and slowly erodes the dry 
layer present in the 850-500mb layer. Rain will move into the lower 
Wabash Valley over the next few hours with a slow expansion to the 
northeast through the morning as that deeper isentropic lift sets 
up. Heaviest rainfall will align across southern portions of the 
forecast area immediately north of the warm front by this afternoon 
with lighter amounts north of Interstate 70.

Rainfall rates will drop back this evening as deeper moisture shifts 
east with a developing wave along the boundary that will become the 
primary surface low as it transitions into the mid Atlantic region 
by Saturday morning. Model soundings though maintain saturated 
conditions below 700mb which combined with the trailing upper level 
wave axis set to pass through prior to daybreak Saturday will 
support light showers lingering through much of tonight. Light rain 
will end prior to daybreak Saturday from northwest to southeast as 
drier air and broad subsidence advects into the region in wake of 
the upper wave. This will ultimately lead to clearing skies from the 
northwest beginning predawn through daybreak Saturday and the return 
of sunshine for much of the upcoming weekend. 

Temps...the model blend continues to be much too optimistic on 
warming for today which will be stunted substantially by the low 
clouds and rain. Nudged 3-4 degrees cooler for highs ranging form 
the upper 40s to mid 50s. The clearing towards daybreak Saturday 
will enable lows to drop into the mid and upper 30s over the 
northern half of the forecast area with 40s further south.

&&

.LONG TERM (Saturday through Thursday)...
Issued at 301 AM EST Fri Nov 21 2025

Seasonably mild and dry weather is expected over the weekend as the 
recent quasistationary front is finally moved out of the region by 
the system expected to bring rain to the area today.

The next rainmaker for the area is the closed low currently over the 
West Coast, which will gradually shift northeastward and may phase 
with a northern stream upper level disturbance as both promote lee 
cyclogenesis over the central Plains, with the resultant surface low 
moving quickly into the Great Lakes early to mid next week. This 
system will bring another round of rain to the area as late Monday, 
with the most significant rain chances Monday night into early 
Tuesday.

Depending upon the intensity of the upper low/trough, there will be 
some low potential for lingering rain as late as Tuesday night into 
Wednesday, but these chances are far more uncertain at this point.

What is more certain is that a fairly substantial cooldown is likely 
for Thanksgiving and beyond, though the exact magnitude of the 
colder conditions remains to be seen. At the moment, highs in the 
30s and lows in the 20s and perhaps upper teens appear likely.

&&

.AVIATION (06Z TAF Issuance)...
Issued at 1216 AM EST Fri Nov 21 2025

Impacts:

- Widespread IFR/LIFR conditions through tonight
- Rain overspreading the terminals predawn hours through the morning

Discussion: 

Very poor flying conditions will continue through the duration of 
the forecast period as moisture remain trapped in the near surface 
layer beneath an inversion. Ceilings hovering early this morning at 
or below 500ft and expect that to continue along with the expansion 
of dense fog at times through and beyond daybreak. Rain will expand 
into the region first reaching KHUF and KBMG in the predawn hours 
then the other terminals through the morning. 

Widespread rain is expected to last into tonight with the potential 
for the heaviest rainfall at KBMG. The onset of rain should flush 
out the dense fog and may help bump up ceilings slightly during the 
day...but IFR and lower conditions will persist. Near calm winds 
through daybreak will shift to E/NE at 5-7kts this afternoon.


&&

.IND WATCHES/WARNINGS/ADVISORIES...
Dense Fog Advisory until 10 AM EST this morning for INZ021-
028>031-035>049-054>057.

&&

$$

SHORT TERM...Ryan
LONG TERM...Nield
AVIATION...Ryan