361
FXUS63 KIND 071042
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
542 AM EST Sat Mar 7 2026

.KEY MESSAGES...

- Widespread minor/moderate flooding south of I-70

- A line of storms producing strong wind gusts will move across
  central Indiana this morning followed by showers into the afternoon

- Additional rainfall amounts will remain under an inch but may
  exacerbate or prolong ongoing flooding

- Well above normal temperatures into next week

- Additional rain likely next week, primarily Tuesday into
  Wednesday, which may prolong the flooding situation

&&

.MESOSCALE UPDATE...
Issued at 514 AM EST Sat Mar 7 2026

Broken convective line moving through eastern Illinois will arrive
in the western forecast area around 1030Z and link up with storms
across the lower Wabash Valley that will gradually become absorbed
with the line. The line appears to have gotten slightly better
organized since 09Z as it has taken on a more north-south
orientation. Recent wind gusts from obs across east central
Illinois associated with the line have largely been peaking at 35
to 40 mph over the last hour.

Limited instability present but presence of the low level jet
advecting slightly higher dewpoints immediately ahead of the line
should enable the convection to maintain intensity or slightly
intensify into our western forecast area over the next hour or so.
Strong wind gusts to near 50 mph remain the primary concern with the
line through daybreak.

&&

.SHORT TERM (Today and Tonight)...
Issued at 259 AM EST Sat Mar 7 2026

Unseasonably warm early morning with skies mainly clear at the
moment along with breezy S/SW winds. At 07Z...temperatures remain in
the mid and upper 60s with convection still to our west over western
Illinois back into Missouri.

That convection has surged out ahead of a cold front that extends
from the upper Midwest southwest into the southern Plains early this
morning. Storms will continue to press east into the region towards
daybreak with a conditional but non-zero threat for severe storms
this morning followed by periodic showers for much of the rest of
the day until the cold front can cross the forecast area late this
afternoon and evening. High pressure will then build in tonight with
drier air gradually advecting into the region and finally bringing a
respite to the wet and unsettled conditions into early next week.

The primary focus through the morning is on the approaching
convection and the conditional severe risk in play. The timing of
the arrival of the convection will likely work in our favor across
central Indiana...impacting the forecast area during a typically
unfavorable time for greater instability and mitigating a more
widespread concern for severe weather. Storms have continued to
weaken over the last few hours with the loss of more robust
instability with the strongest storms currently across southern
Missouri. Extrapolation brings the convection to the Wabash Valley
between 10 and 11Z then shifting east across the area throughout the
morning.

With that being said...trends do support a surge of slightly deeper
moisture along a narrow axis into the western forecast area shortly
before daybreak. That would lead to a nudge up in CAPE values and
with ample shear and SRH values present within the boundary layer...
it is not out of the question that we see a subtle uptick in
convection as it moves into the forecast area. In addition...the
deeper moisture plume will also aid in weakening a lingering shallow
inversion. With the low level jet over the area and 50kt flow as low
as 2500ft AGL...there will be a narrow window along the leading edge
of the convection for storms to generate stronger wind gusts in
excess of 50mph. The winds will be the primary concern from the
storms with largely unidirectional flow present through the column.
Brief heavy rainfall will also accompany the storms and while overall
rainfall amounts today should remain under an inch in most
locations...any additional rainfall will exacerbate or prolong
ongoing flooding.

Convection will press east across the forecast area and should move
out of the forecast area by midday. Showers will linger behind the
initial convective line...ending from northwest to southeast through
the first part of the afternoon. A narrow line of showers will
accompany the trailing cold front which will swing across the
forecast area late this afternoon into the early evening. Rain
should be out of the area by mid to late evening with drier air
expanding into the region above a sharp boundary layer inversion
which will hold for most if not all of tonight. This will keep a
broad area of stratus over the forecast area tonight.

Winds will be gusty through this evening peaking at 25 to 30mph at
times this afternoon immediately ahead of the cold front. Southwest
flow will veer to W/NW in wake of the frontal passage late today.

Temps...expect another mild day with temperatures rising slightly
from current readings through early afternoon then falling late day
with the frontal passage. Lows tonight will range from the upper 30s
in the northern Wabash Valley to the mid 40s across southeast
portions of central Indiana.

&&

.LONG TERM (Sunday through Friday)...
Issued at 259 AM EST Sat Mar 7 2026

A break from rain chances can be expected to last through Monday
evening as a broad surface high moves through the region in the wake
of the departing front, but rain chances will return as early as
late Monday night and continue through mid week as the northern
stream and a southwestern CONUS cutoff low combine to promote
moisture transport back into the region along and ahead of a lengthy
frontal zone stretching from a strong surface low over the eastern
Canadian provinces back to an area of lee cyclogenesis over the high
Plains.

Guidance has trended back toward more phasing of the southwestern
cutoff low and the prevailing westerlies, which may enhance heavy
rainfall potential, primarily late Tuesday into Wednesday as the
front moves through.

Even with a short break from rain, antecedent conditions between the
ongoing river flooding and waterlogged ground will mean that it will
not take much in the way of heavy rainfall rates to produce renewed
areal and perhaps flash flooding, as well as potentially prolonging
if not exacerbating the river flooding situation, so this will need
close monitoring as the situation evolves over the weekend into next
week.

Will have to keep an eye on potential for at least a marginal severe
threat per experimental ML/AI severe guidance, though the hydrologic
concerns would be the more pressing of the two at this point,
obviously, and any severe threat would be supported by details that
are conditional and extremely unclear at this point.

The quasizonal flow along with broad warm advection ahead of the mid
week front will keep temperatures well above normal throughout much
of the coming week, with near record highs again not completely out
of the question Monday and Tuesday. A bit of a cool down appears
possible post front late in the period into next weekend and perhaps
beyond, though uncertainty is high on just how long it lasts - but
latest 8-14 day outlook does show a tendency toward below normal
temperatures for the third week of the month. Warmer NBM forecasts
near climatology late in the long term will likely end up falling
with time if model trends hold.

&&

.AVIATION (12Z TAF Issuance)...
Issued at 542 AM EST Sat Mar 7 2026

Impacts:

- Narrow convective line impacting the terminals this morning with
  peak gusts to 35kts for a short time

- Showers continue into the afternoon with periodic wind gusts
  peaking at 25 to 30kts

- Cold front moves through late this afternoon and early evening
  with a wind shift to W/NW

- MVFR ceilings at times today, becoming more widespread this
  evening before scattering in the predawn hours Sunday

Discussion:

Convection is moving into western Indiana early this morning and
will impact the terminals from west to east through mid morning.
Potential for wind gusts up to 35kts for a brief period as the
convective line moves across the area. Behind the storms...showers
will continue through early afternoon before moving off to the east.
After a brief break in the rain...a thin line of showers will
accompany the cold front as it tracks through the region late this
afternoon and early evening.

MVFR ceilings are possible at times today but will become more
prevalent this evening as a broad area of post-frontal stratus
settles over the area. Skies will clear from the west during the
predawn hours Sunday. Southwest winds will continue to gust as high
as 25 to 30kts at times throughout the day. Winds will veer to W/NW
with the passage of the cold front...gradually decreasing tonight.

&&

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

&&

$$

MESOSCALE...Ryan
SHORT TERM...Ryan
LONG TERM...Nield
AVIATION...Ryan