119
FXUS63 KIND 191433
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
1033 AM EDT Mon Oct 19 2026

.KEY MESSAGES...

- FROST ADVISORY in effect until 900 AM for patchy to widespread
  frost across central Indiana

- Dry and quiet weather persists this week...subtle moderation
  amid overall slightly above normal temperatures

&&

.FORECAST UPDATE...
Issued at 1032 AM EDT Mon Oct 19 2026

Temperatures are steadily warming under clear skies and calm winds
with the influence of high pressure. Updated the temperatures to
better match the warming trend this morning but still expecting
highs in the upper 60s to low 70s.

While winds will be light, surface flow is generally out of the
south which will help promote slight warming and lows tonight are
expected to be warmer than last night with lows down to near 40.

&&

.DISCUSSION (Today through Sunday)...
Issued at 228 AM EDT Mon Oct 19 2026

Today and Tonight...

On the heels of the first freeze of the season for approximately
half of central Indiana`s zones Sunday morning...patchy to
possibly widespread frost will be the rule early today...while no
areas drop below 33 degrees. Therefore maintaining Frost Advisory
for the entire CWA through 900 AM EDT, although latest trends
suggest slightly less organized frost with dwpts so far hanging up
in upper 30s to near 40F in several, mainly western/southern
counties.

Broad and tranquil surface high pressure will facilitate placid
autumnal conditions for the start of the workweek.  Shift of ridge
axis out of Indiana to the east will promote modest moderation of
H850 temperatures that will equate to a 3-5 degree increase in
temperatures compared to Sunday.  Mainly clear skies into most of
the afternoon will yield to some cirrus crossing from west to east,
especially north of I-70, due to a couple very weak mid-level waves
that will have no chance of getting any precipitation through the
very dry column.  Recent trend in diminishing winds will continue
with light flow the rule for at least the next 24 hours...with
overall variable headings possibly focusing out of the SSE later
today.

Following locally marginal fire weather conditions Sunday...slight
rebound of dewpoints/higher minimum RH values and light winds today
will prevent fire conditions.  High temperatures this afternoon will
range from mainly upper 60s to around 70F along the Wabash Valley
and southwest of Monroe County.

Tuesday through Thursday...

Zonal ridge across the eastern two-thirds of the CONUS on Tuesday
will build northward over the Plains through the mid-week.
Meanwhile broad and amplified surface high pressure aligned along
the eastern half of the continent will gradually shift its center
from southwestern Quebec back into the Great Lakes by Thursday. This
will translate to an unseasonably weak surface gradient over central
Indiana under occasional cirrus.  Wider diurnal temperature ranges
will be generally 25-30 degrees...with any overall trend in readings
modest and most likely moderating as the building upper ridge to the
west allows T850 values to reach 10 degrees Celsius by Thursday.

Surface ridge axis aligned southwestward into East Texas will block
any organized return of Gulf moisture.  Column moisture will be
limited to precipitable water values of 0.90 inches or less,
maintaining generally mostly clear skies and surface dewpoints in
the 40s to around 50F.

Friday through Sunday...

Dry and placid Mediterranean-like conditions to continue under
stacked high pressure late this week as amplified upper ridge glides
slowly from the eastern Plains to the Ohio Valley.

Early winter storm tracking near Hudson Bay later in the weekend
should drag the tail of its cold/stationary front across the Midwest
by Sunday.  However, low confidence in return of any noteworthy
moisture ahead of this boundary with stubborn and huge southeastern
ridge blocking/displacing any Gulf moisture well W/NW of Indiana...
with only scattered mid/high clouds expected.  Perhaps more notable
will be return of light breezes that will veer from easterly Friday
to southwest by the end of the weekend.  Surprising quiescence in
further temperature trends as potent mid-level vort supporting the
Canadian system likely suppresses central US ridge somewhat...with
readings most likely maintaining range from 40s to 70-75F.

The normal max/min through the forecast period at Indianapolis is
63/43. Temperatures across central Indiana will range from
seasonably cool early mornings to slightly above to above normal
afternoons.

&&

.AVIATION (12Z TAF Issuance)...
Issued at 702 AM EDT Mon Oct 19 2026

Impacts: None expected

Discussion:

VFR conditions are expected to continue near central Indiana
terminals into Tuesday morning.  Stagnant elongated surface high
pressure axis draped across Indiana will maintain mostly clear
skies...except when very weak upper-level forcing spilling over
modest H500 ridge, brings only FEW/SCT cirrus late today and
tonight.

Light and often variable winds will prevail through the TAF period,
with perhaps a few hours of southeasterly flow under 7KT this
afternoon.


&&

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

$$

UPDATE...KF
AVIATION...AGM
DISCUSSION...AGM