553
FXUS63 KIND 200112
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
912 PM EDT Sun Apr 19 2026

.KEY MESSAGES...

- A Freeze Warning is in effect tonight into early Monday for the
  northern half of central Indiana; A Frost Advisory is in effect
  tonight for the remainder of central Indiana.

- Warming trend beginning on Tuesday, with storm chances Tuesday
  night into Wednesday

&&

.FORECAST UPDATE...
Issued at 912 PM EDT Sun Apr 19 2026

Surface analysis this evening shows strong high pressure in place
over the upper midwest. This system was building southeast toward
Indiana. GOES19 shows a few lingering diurnal CU still waning across
Central Indiana, but the overall clearing trend was underway. Gusty
winds across the area had also subsided. Aloft, water vapor shows
the upper flow with ridging in place across the western CONUS and
lee side northwest flow across the upper midwest spilling into
Indiana...a classic high pressure subsidence pattern. Dew points
across Central Indiana were in the upper 20s to lower 30s.

No significant changes to the ongoing forecast. Models suggest the
surface high to build southeast toward Indiana overnight. This will
lead to clear skies and light winds. Given our current dew points,
our freeze warning and frost advisories look to be in good shape.

&&

.DISCUSSION (This evening through Sunday)...
Issued at 211 PM EDT Sun Apr 19 2026

Central Indiana has been under a pattern change the last 24
hours as a large low pressure system has pushed off to the northeast
allowing cool northwest flow to reach the Ohio Valley. That said,
low level winds have backed towards W/WSW throughout the day ahead
of a weak mid level short wave, embedded within the CAA. Confluence
along this wave will tap into the limited moisture to aid in cumulus
development throughout the afternoon. A modest low level jet and
deep mixing will create gusty winds this afternoon, peaking around
40 MPH.

While any rain should be sparse, steep lapse rates combined with the
forcing might just be enough to get a few isolated showers over NE
portions of central Indiana. The steep lapse rates will promote good
mixing, which will bring down some of the stronger winds aloft. This
will likely result in wind gusts peaking in the 30 to 40 mph range
this afternoon. The inverted V soundings indicate the potential for
higher gusts from any showers that do develop.

Reinforced CAA behind the wave along with broad AVA will aid in
pressure gains throughout the column. This will bring mostly clear
skies and keep temperatures below normal. All of central Indiana is
likely to be slightly cooler tonight, dropping temperatures into the
low to mid 30s over most of the area. Given this, a Freeze Warning
has been continued for the northern half of central Indiana, with a
a Frost Advisory for the rest of the area.

The rest of the forecast period will be focused on temperature
recovery as deep troughing over the Atlantic Coast helps induce
ridging upstream and strong WAA throughout the middle of the week. A
weak shortwave will pass through late Tuesday into Wednesday
providing chances for showers and storms, but otherwise most of the
forecast period prior to Friday night will remain dry. Temperatures
will begin cool on Monday but quickly increase within the
aforementioned WAA, reaching back above normal by Wednesday with
highs in the mid to upper 70s.

Late week, deep pressure depletion within a coupled upper level jet
will likely provide increases in rain chances late Friday through
the beginning of the weekend. Dynamics aloft should be stronger
within this system, leading to increases in potential hazards, but
there is still a lot of uncertainty regarding the systems evolution
and progression. As of the latest ensemble run, the best chances for
severe weather will likely remain west of central Indiana.

&&

.AVIATION (00Z TAF Issuance)...
Issued at 629 PM EDT Sun Apr 19 2026

Impacts:

- VFR conditions this TAF period.

Discussion:

Diurnal CU across the area will quickly dissipate this evening as
daytime heating is lost. This will result in mostly clear skies.
Winds across the area will also subside as mixing is lost and high
pressure over the upper midwest builds across Indiana.

High pressure will be moving across Indiana on Monday. This will
lead to mostly clear skies, light winds and continued VFR conditions.


&&

.IND WATCHES/WARNINGS/ADVISORIES...
Freeze Warning from 2 AM to 9 AM EDT Monday for INZ021-028>031-
035>049-054>057.

Frost Advisory from 2 AM to 9 AM EDT Monday for INZ051>053-
060>065-067>072.

&&

$$

UPDATE...Puma
AVIATION...Puma
DISCUSSION...Updike