Indiana’s Weather For Sunday

HEADLINES
– High clouds, and higher temps for Mom!
– Periodic shower and thunderstorm chances expected much of this week.
– Some severe risk possible Thursday-Thursday night.
– Warmest air of the year. Near-record highs possible Thursday.

TODAY’S MAP

NWS TECHNICAL DISCUSSION

A cold front, enhanced by the cool waters of Lake Michigan, pushed
southward into Indiana late yesterday. The boundary is still working
its way through the state, but has weakened and become quite
diffuse. High-resolution guidance suggests a secondary boundary,
this time off of Lake Erie, enters Indiana from the northeast around
sunrise. Winds should therefore turn from northerly to a more
northeasterly direction. A few gusts up to around 20 knots are
possible after that boundary passes through. Winds then weaken
through the day today while becoming more easterly with time.

High temperatures should be similar to yesterday, though a bit
warmer across our south as boundary layer mixing looks a bit deeper.
Overall, expect highs in the upper 70s to near 80 in spots. A large
mid/upper level low to our south will continue to provide occasional
cirrus which may become quite thick at times. A few diurnal cumulus
are possible but model soundings suggest this will be fairly limited.

Low temperatures tonight should be modulated by increasing cloud
cover as the low to our south lifts northward. While lows across the
board should be warmer than the previous night, we will see a
distinct gradient in temps across the region. Across our north,
where less cloud cover is anticipated, lows may dip into the low to
mid 50s. Further south, under thicker cloud cover, lows may only
reach 60 or so.

Moisture continues to increase into Monday morning with thickening
mid to low-level clouds. A few isolated showers may be possible as
soon as sunrise Monday.

&&

.LONG TERM (Monday through Saturday)...
Issued at 324 AM EDT Sun May 11 2025

The next work week will more closely resemble summer across central
Indiana as a broad yet rather weak southern stream trough brings
moderate humidity and at least a couple rounds of showers/t-
storms...before a building upper ridge provides near-record warmth
north into the Midwest for Thursday-Friday.

Monday through Wednesday...

Latest guidance runs are showing increasing confidence in widespread
rain showers Monday...especially across southern zones where a few
rumbles of thunder will be possible...with greatest rain chances for
all locations during afternoon hours.  The ebb and flow of coverage
of showers will be very much diurnally-driven, with confidence also
up for a second round Tuesday through mainly the afternoon...albeit
with a more scattered, and non-severe, thunder threat.  Wednesday
should have the best shot of bringing rain-free weather of the
period`s first three days, yet a isolated showers/t-storms will be
around as the last portions of the lifting trough cross the region.

Modest moderation through above-normal levels with most locations
trending from mid-70s Monday to low-80s Wednesday...although
persistent dewpoints in the low 60s will keep an unseasonably humid
feel with mornings starting in the 60s. Total rainfall should be
under 0.50 inches for most locations, with isolated moderate
precipitation, especially towards the Ohio Valley.

Thursday through Saturday...

Noteworthy pattern change for the late workweek will find a
retracted, yet deep synoptic system over south-central Canada...
which will allow a subtropical upper ridge to build from the Mexican
Highlands into the central CONUS/Midwest.  Robust southerly gusts on
Thursday are progged to boost readings into the upper 80s across the
CWA, while perhaps pushing dewpoints towards 70F for some areas.  A
conditional threat for potentially strong/severe t-storms will exist
around PM hours Thursday...when the southeastern-most appendage of
the interior system`s energy likely drags east across the southern
Great Lakes. This could focus a brief period of inordinate
precipitable water, record heat, and therefore copious instability,
with ample vertical wind shear...although this conditional potential
will continued to be examined in the coming days.

Long term`s last two days are expected to trend towards present yet
lower humidity and more reasonable above-normal warmth...when the
occluded Canadian system should drag/linger its cool frontal zone
near the local region.  A few more showers/isolated t-storms would
be possible amid conditions that would be considered pleasant for
early summer.  The normal max/min at Indianapolis through the long
term is 73/53.

&&

.AVIATION (12Z TAF Issuance)...
Issued at 644 AM EDT Sun May 11 2025

Impacts:

Rain showers and possible MVFR ceilings developing Monday morning.

Discussion:

Winds are out of the north behind a weak cold front that passed
through late Saturday evening. Winds should remain generally out of
the north and under 10 knots until a secondary front pushes in from
the northeast this morning. Winds increase to around 10 knots,
becoming northeasterly, with a few gusts as high as 20 knots.

Cirrus continues to ebb and flow but is expected to gradually
increase in coverage today. Low-level moisture slowly increases from
the south as well, leading to occasional mid-level clouds and
finally low-level clouds after about 00z. Low-level clouds continue
to thicken overnight, potentially becoming an MVFR ceiling by 12z
Monday morning.

Rain showers are possible beginning around 12z Monday. These should
be widely scattered to start with low probability of occurrence at
any specific terminal. However, rain chances increase towards the
end of the TAF period, with the best chance of rain after about 18z
Monday. Thunder may be possible as well but chances for that appear
lower than for rain in general.

&&

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

$$

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

NWS CHARTS FOR TODAY/TONIGHT