412
FXUS63 KIND 212143
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
543 PM EDT Thu May 21 2026

.KEY MESSAGES...

- River and stream flooding continues across southern portions of
  Central Indiana.

- Cooler today with a brief break from rain chances, before
  showers and storms return to the forecast Friday into the
  holiday weekend, along with a return to warmer temperatures.

&&

.DISCUSSION (This evening through Thursday)...
Issued at 303 PM EDT Thu May 21 2026

Current surface analysis depicts surface high pressure centered
across the northern Great Lakes stretching down into parts of the
Ohio Valley while a subtle wave moves across Ohio. Mostly cloudy
skies have lingered primarily near the I-70 corridor and south due
to weaker subsidence being further away from the surface high. Some
breaks in the clouds are occurring though thanks to daytime heating
despite the weaker subsidence. Look for quiet weather conditions to
continue through tonight under the influence of surface high pressure
to the north.

A more active pattern develops Friday through the weekend with
multiple disturbances moving across the region. Model guidance
depicts a mid-level shortwave and associated surface low lifting a
warm front northward on Friday leading to increasing rain chances.
Residual subsidence induced dry air will limit rain chances to
mainly south-central IN Friday morning. Moisture surging northward
should then allow for precipitation to overspread the northern half
of central IN during the afternoon hours. Far northwestern counties
may struggle to see more than a few hundredths of QPF due to the dry
air. Weak instability may promote isolated embedded thunderstorms.

Sufficient moisture combined with forcing from the departing first
impulse and another disturbance moving in Saturday will keep
precipitation chances elevated. The highest precipitation chances on
Saturday are focused across the eastern half of the CWA where the
strongest forcing is expected. Instability appears to be weak again
on Saturday, but isolated thunderstorms are possible.

Look for subtle ridging to build in late Saturday into Saturday
night providing quiet weather before yet another shortwave moves in
on Sunday. Sunday morning should start off mostly quiet as ridging
shifts eastward. A shortwave and associated weak surface low will
then move in Sunday afternoon supporting increasing precipitation
chances. Model disagreement regarding the evolution of this
relatively weak system leads to lower confidence in convective
coverage during the afternoon hours. However, most guidance depicts
modest forcing and moisture advection promoting scattered convection
as the PBL heats up ahead of a weak frontal boundary.

An unsettled pattern is likely to continue through next week with
daily chances for showers and storms. Long range guidance depicts
multiple impulses aloft traversing the region while gulf moisture
continues to gradually advect northward. Look for temperatures to
moderate Friday through the weekend. Highs are expected to reach the
low 80s by Sunday with highs in the 80s for much of next week.

&&

.AVIATION (00Z TAF Issuance)...
Issued at 542 PM EDT Thu May 21 2026

Impacts:

- Mainly Low VFR Cigs overnight.

- MVFR ceilings likely developing Friday with showers aft 18-19Z.

Discussion:

GOES19 shows stratocu over IL, Western IN and southern Indiana.
Easterly surface flow in place was trying to decay these clouds.
However as cooling continues this evening, a warm front will begin
to approach Central Indiana from the south. Forecast soundings and
time heights keep mainly low VFR or MVFR cigs across the area
overnight as this occurs.

Low pressure and an approaching cold front will push across Central
Indiana on Friday. This will bring MVFR CIGS and rain showers to
most of the TAF sites. HRRR remains on board with this, showing a
shield of rain arriving on Friday afternoon before exiting late
Friday evening.

&&

.IND WATCHES/WARNINGS/ADVISORIES...
None.
&&

$$

AVIATION...Puma
DISCUSSION...Melo