Marco, Indiana Weather Forecast Discussion

005
FXUS63 KIND 221856
AFDIND
Area Forecast Discussion
National Weather Service Indianapolis IN
256 PM EDT Mon Sep 22 2025
.KEY MESSAGES...
- Rain and thunderstorms come to an end this evening.
- Patchy fog overnight, locally dense.
- Milder with daily chances for showers and a few thunderstorms
  through much of the work week.
&&
.SHORT TERM (This evening through Tuesday)...
Issued at 255 PM EDT Mon Sep 22 2025
Steady rain continues across the eastern half of our CWA as of 2pm.
Rain will continue to push eastward, ending before sunset for the
majority of our area. A few showers may linger into the evening
especially across our southeast. Rainfall totals have been mostly in
the 0.25" to 0.50" range across the Indy metro, with amounts between
0.50" to 1.5" further south. A locally higher amount near 2.0" is
possible today as well. Ponding of water on roadways is possible in
heavier showers/storms. The Flash Flood threat is low today, due to
relatively fast storm motions and moderate only occasionally heavy
rainfall rates.
Not much of an air mass change is noted within guidance following
today`s system. With most of the area seeing a steady soaking rain,
a very moist boundary layer will be left in place overnight. Light
subsidence between today`s system and another over the central
Plains will allow for partial clearing. Light winds, clearing, and
high PBL moisture content will set the stage for fog formation
tonight. Fog may be locally dense, especially from Terre Haute to
Kokomo southward...which is where the bulk of today`s rain has been.
Again, fog depends on how much clearing occurs this evening / early
tonight. A short-fuse Dense Fog Advisory may be needed if clearing
is greater than anticipated.
On Tuesday, we`ll be between systems as mentioned above. The day may
end up mostly dry with broad subsidence in place. However, that is
not expected to last long as the upstream system over the Plains
approaches. Guidance shows large-scale ascent arriving as soon as
00z, increasing thereafter. Showers and thunderstorms are possible
Tuesday night onward, with varying coverage depending on which model
one looks at. We introduce chance PoPs towards the end of the short
term, increasing overnight.
As for temperatures, expect lows in the 60s tonight with lower
values found further north and in areas that see clearing. A larger
rebound is anticipated Tuesday due to less rain and increased
sunshine with highs climbing to near 80.
&&
.LONG TERM (Tuesday night through Monday)...
Issued at 255 PM EDT Mon Sep 22 2025
As we reach the middle of the week, there is a large consensus on a
quickly dropping mid to upper level trough becoming cut off from the
parent upper level flow. However, this consistency does not continue
to the surface with a wide range in possible outcomes with the track
of the associated surface low. Generally, this should lead to
overall cooler and wetter conditions for Wednesday and Thursday, but
total QPF varies greatly depending on where the low tracks. A track
across the Ohio Valley would likely lead to the precipitation axis
across Southern IN and Northern KY, whereas a track further south
could lead to more sporatic precipitation. In higher end scenarios,
2-3" of rain over southern portions of Indiana are possible.
Expected highs Wednesday and Thursday are in the low to mid 70s
depending on where greatest rain and cloud depths occur.
This weekend, weak upper-level ridging returns, sufficient enough to
remove chances for rain and push temperatures back above normal.
Friday will will be a transition day with departure of rain and
temperatures remaining near seasonal. However, this weekend forecast
highs are near 80 with dew points in the upper 50s.
&&
.AVIATION (18Z TAF Issuance)...
Issued at 146 PM EDT Mon Sep 22 2025
Impacts:
- MVFR/IFR conditions expected through tonight
- rain this afternoon, ending by the evening.
- Fog developing overnight, locally dense.
Discussion:
Rain and a few embedded thunderstorms continue for HUF, BMG, and
IND. Rain will end shortly at HUF but persist for a few more hours
at BMG and IND. A few scattered showers may linger into the evening
as well. IFR to MVFR conditions are likely during rain/storms.
As the rain clears this evening, lingering moisture may set the
stage for some overnight fog. Fog is possible at all terminals, and
depends on how much clearing we get overnight. Locally dense fog is
possible with visibility under 1/4 mile.
Fog diminishes during the morning hours Tuesday but a lingering MVFR
ceiling is possible into the afternoon hours. An eventual return to
VFR ceilings is expected during the afternoon.
Winds are out of the southeast currently between 5-8kt, and may go
light and variable overnight, before returning to a more southerly
direction tomorrow. Speeds expected to be under 10kt through the TAF
period.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SHORT TERM...Eckhoff
LONG TERM...Updike
AVIATION...Eckhoff

NWS IND Office Area Forecast Discussion