004
FXUS63 KIND 221422
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
1022 AM EDT Fri May 22 2026

.KEY MESSAGES...

- Rain spreads north across much of central Indiana today with
  continued below normal temperatures

- Rain chances continue through the holiday weekend into next week,
  but temperatures will become above normal for much of the period.

&&

.FORECAST UPDATE...
Issued at 1020 AM EDT Fri May 22 2026

Forecast is on track for today. A mid level vort max will push to
the north throughout the day with widespread vertical lift through a
moist troposphere leading to numerous or greater shower coverage
this afternoon and evening over a majority of central Indiana. There
is a little bit of low level convergence ahead of the wave that
could lead to sporatic showers late this morning through the early
afternoon prior to the arrival of steady light rainfall.

Total rain amounts will vary across the region, but generally those
S/E of I-69 are expected to get 0.5-1.5" with lesser amounts to the
N/W. There is a potential scenario where FGEN banding on the NE side
of the low late this evening and tonight could lead to narrow bands
of 2.5-3.5 inches (total), but mid level dry air advection will be
working against this, leading to high uncertainty on this occurring.
If this does occur, localized flooding will be likely especially
along streams/waterways and low lying areas.

&&

.DISCUSSION (Today through Thursday)...
Issued at 250 AM EDT Fri May 22 2026

Today through Saturday...

The early morning hours will remain quiet. Later this morning,
forcing from an approaching upper trough will increase. Initially,
moisture will be limited in the lower levels thanks to easterly
winds. This may limit rain coverage for a while. However, by late
morning into early afternoon, the lower levels will become more
favorable for rain.

Forcing will continue to increase with the upper trough and an
approaching surface low, allowing rain to spread north this
afternoon. By the end of the today period, the northwest 3/4 of the
forecast area will have likely or higher category PoPs. The
northwest quarter will have less forcing and moisture, so will keep
PoPs in the chance category.

Rain will continue into the early overnight, especially east, as the
surface low moves through the area. Coverage will then diminish from
west to east tonight as the surface low continues to push east.

For Saturday, weak upper energy along with a lingering surface
trough will keep some lower PoPs around, mainly east. Highest PoPs
will generally be in the morning, with some decrease from west to
east during the day.

With the low level jet pointed to the east of the area, the heaviest
rain will fall east of central Indiana. However, portions of the
southeast may see around an inch of rain.

There will be some weak instability which could lead to a few non-
severe thunderstorms this afternoon into the early overnight.

Trimmed guidance`s high temperatures today given expected cloud
cover and rain, and nudged guidance temperatures down Saturday
afternoon with lingering cloud cover.

Sunday and Memorial Day...

A larger upper trough along with a surface front will move into the
area Sunday. This will bring a threat for showers and some
thunderstorms, mainly Sunday afternoon when instability is
maximized. There remains some uncertainty in the timing of the
forcing and coverage of rain, so confidence in likely PoPs Sunday
afternoon is medium at best.

With the front lingering not far south of the area and weak upper
energy moving through Sunday night into Memorial Day, will keep some
low PoPs around, especially south.

Temperatures during this period will depend on sky cover and rain
coverage, but highs around 80 look reasonable for now.

Tuesday onward...

Uncertainty in how the upper pattern will develop leads to lower
confidence in the forecast for this period, with generally a large
upper low across the western USA and an upper ridge southeast. Will
keep some PoPs around through the period, but again confidence in
any one day`s PoPs is low. Temperatures look to be above normal with
some influence from the ridging to the east expected.

&&

.AVIATION (12Z TAF Issuance)...
Issued at 551 AM EDT Fri May 22 2026

Impacts:

- Conditions deteriorate to IFR at most sites this afternoon
- Showers spread north this afternoon
- Wind gusts around 20kt at KLAF today

Discussion:

Moisture will continue to increase today, with gradually lowering
ceilings. As low pressure approaches from the south this afternoon,
showers will spread north across the sites. By 21Z, IFR ceilings and
showers will be common. KLAF will take longer to reach IFR and will
have the lowest chances for showers.

Isolated thunderstorms are possible this afternoon and evening, but
coverage will be too low to mention in the TAFs. Low ceilings will
persist into Saturday morning.


&&

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

$$

UPDATE...Updike
AVIATION...50
DISCUSSION...50