010
FXUS63 KIND 201034
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
634 AM EDT Fri Mar 20 2026

.KEY MESSAGES...

- Above normal temperatures through the weekend, with near record
  highs on Sunday

- Showers and thunderstorms possible on Sunday, a few strong to
  severe storms cannot be ruled out.

- Mostly dry and warmer than average conditions expected next week.

&&

.SHORT TERM (Today and tonight)...
Issued at 104 AM EDT Fri Mar 20 2026

Anomalous ridging over the western US has edged eastward enough to
allow for a significant warm up yesterday compared to earlier in the
week. The ridge center is located over the Four Corners region, and
so Indiana will reside under broad northwesterly flow aloft.

A clipper system caught up in this flow should pass to our north
today. Warm air advection ahead of these systems is typically under
done by guidance. Assuming efficient boundary layer mixing,
temperatures in the upper 70s to near 80 are possible this
afternoon. However, increasing high-level cloud cover may inhibit
this to some extent. As such, we will nudge high temps towards the
upper end of the guidance envelope but keep temperatures lower than
what would occur under ideal settings.

A cold front behind the departing clipper drops southward Friday
night, with high pressure quickly building in. Temperatures drop
quickly into the 40s and perhaps upper 30s by Saturday morning. The
shot of cold air looks to be short-lived as the surface high quickly
slides eastward. Winds become southerly once again by Saturday
afternoon with clearing skies. Another day with temperatures
exceeding guidance appears likely. We will once again trend our
forecast towards the upper end of guidance with highs near 70 for
most.

&&

.LONG TERM (Saturday through Thursday)...
Issued at 104 AM EDT Fri Mar 20 2026

Anomalous ridging continues into the long range, though guidance
tends to flatten the ridge somewhat by Sunday. Yet another clipper
system dives southeastward within the northwesterly flow aloft. As
mentioned above with the first clipper, temperature advection tends
to be under done. That line of thinking continues here, and we will
nudge Sunday`s highs towards the higher end of guidance yet again.
Assuming today doesn`t hit 80 (which is possible), we have a fairly
good chance at seeing it on Sunday. For many, that would be the
first 80 degree day of the year.

One key difference between the two clippers is that there looks to
be greater moisture advection ahead of Sunday`s clipper.
Additionally, the second clipper`s attendant cold front appears
quite a bit stronger. Most guidance is now trending towards an area
of showers and thunderstorms developing along this front as it drops
southward Sunday afternoon. There is a chance that some of these
storms could be severe, since guidance is showing a fairly
impressive shear and instability overlap.

Steep lapse rates between 7 to 8 C/km result in CAPE between 1000-
2000 J/Kg. Of particular interest is how deep these CAPE profiles
are. Model soundings show equilibrium levels (EL) near 12km, which
is very high for March. Model hodographs are long and curved, which
supports supercell potential as shear vectors are not parallel to
the front. However, as mentioned above, the front is rather strong
and storms could grow upscale quickly.

Taking a look at the lower portion of the model soundings, there
appears to be an elevated mixed layer (EML) beginning around 850mb.
This could effectively cap the environment, especially further west
where the EML is more robust. The best chance of storms is closer to
the clipper itself, which will pass well to our northeast. Given the
cap in place and the best forcing displaced to our northeast...the
limiting factor on Sunday would be initiation potential. There is a
decent chance that the cap wins and storms fail to initiate. As
such, the threat is conditional. But should a storm develop, it
poses a threat for severe weather.

In terms of potential hazards, fast flow increasing with height all
the way to the EL supports efficient storm top ventilation combined
with steep lapse rates, this points towards large to very large hail
being a possibility should storms develop. With some low-level
curvature in the hodographs, tornado potential exists but may be
mitigated by deep PBL mixing and high LCLs, as well as the strength
of the front which could undercut storms. Severe wind gusts are
possible given steep lapse rates and dry air within the EML that
could promote cold down drafts.

NEXT WEEK

A continuation of the current weather pattern is favored for next
week. Ridging across the western US attempts to rebuild itself and
northwesterly flow aloft persists across the Midwest. As such, we
will see periods of warming followed by systems passing to our north
with a shot of cold air behind them. Overall, this pattern supports
warmer-than-average temperatures with relatively dry conditions.

&&

.AVIATION (12Z TAF Issuance)...
Issued at 633 AM EDT Fri Mar 20 2026

Impacts:

- SW to WSW winds increasing to 10-15KT by 16Z
- Winds veering through TAF period from SW to NE, with greatest
  change within 19Z-02Z today
- Winds gusting up to 21-24KT during 16Z-22Z

Discussion:

VFR to continue over central Indiana terminals through Friday night
under mainly SCT/BKN high cloud.  Next weather system crossing the
Great Lakes and New England during the TAF period...will promote
robust gusts and drag its cold front south through the region this
afternoon.

Increasing gradient ahead of this boundary will boost winds to 10-
15KT by 16Z today...with afternoon gusts up to 21-24KT.  Flow will
veer through the TAF period, most notably with the fropa from
westerly to northerly in about 3-4 hours within 19Z-02Z. Winds to
fall to around 5KT at most terminals by late this evening.

Low chances of MVFR visibility in fog towards 12Z Saturday at KIND
and KLAF, but confidence too low to include in TAFs.

&&

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

$$

SHORT TERM...Eckhoff
LONG TERM...Eckhoff
AVIATION...AGM