112
FXUS63 KIND 121858
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
258 PM EDT Tue May 12 2026

.KEY MESSAGES...

- Showers and a few t-storms tonight, gusty winds possible

- Dry and seasonable Wednesday through Friday

- Warming trend this weekend and into next week with daily storm
chances. Potential for first 90 degree day of the year next week.

&&

.DISCUSSION (This evening through Tuesday)...
Issued at 258 PM EDT Tue May 12 2026

Tonight through Thursday Morning.

Dry and warmer weather this afternoon and evening across Central
Indiana ahead of an approaching cold front for tonight. Satellite
and radar imagery show a line of showers and a few thunderstorms
storms along a front extending from the UP of Michigan southwestward
into Iowa. The environment ahead of this front is very dry with
surface dew point depressions of 25-30 degrees due to afternoon
mixing. This dry air will significantly limit the overall severe and
heavy rainfall threat tonight; however CAMs do show modest moisture
advection into the region as the low level jet ramps up after sunset
and mixing wanes. Due to such dry air in the lower levels and
stepper 0-3km lapse rates,suggests a marginal wind threat may exist
with storms as they approach NW portions of Central Indiana in the
10-11pm timeframe. Instability is marginal at best with most CAMs
showing 200-400 J/kg of CAPE for storms to tap into. Best chance for
a strong storm or wind gust above 50 mph will likely be in the NW
quadrant of Central Indiana, with the severe and thunder threat
waning as convection encounters drier and more stable air to the
southeast.

Dry air quickly advects in behind the cold front as high pressure
drops southeast into the Plains. Lingering low clouds may persist
into the early to mid morning hours before lifting during the
afternoon and breaking up. The NW pressure gradient behind the front
remains tight enough to support gusty winds into tomorrow especially
with steeper low level lapse rates and mixing during the afternoon.
Some hi-res guidance suggests wind gusts of 25-30 mph during peak
heating of the day tomorrow, a little over what the NBM depicts,
which seems very reasonable. Temperatures may struggle to get into
the lower 60s tomorrow north of I-70 as a fairly cold airmass for
this time of year advects in aloft. Deeper mixing should help
temperatures recover during the afternoon, yet still remain below
normal for mid May with winds making it feel even colder. Expect a
good N-S temperature gradient across the state tomorrow afternoon
with upper 50s to low 60s across the north and low 70s in SW and
Southern Indiana.

High pressure becomes centered overhead late Wednesday night into
Thursday, setting the stage for another cold night across Central
Indiana due to radiational cooling. With such a cool and dry airmass
in place (dew points in the mid 30s), some locations in North
Central Indiana may dip down into the mid to upper 30s. For now the
forecast keeps lows at or above 39 degrees, but may need to be
adjusted down a few degrees in more rural locations. Widespread
frost is not expected, but still possible in rural locations north
of I-70.

Thursday through Early Next Week.

A prolonged period of increasingly warm weather is expected late
this week and through the early weekend, but with an increase in
daily storm chances as well. Surface high pressure will firmly
establish itself over the Ohio Valley on Thursday and Friday,
promoting mostly sunny skies, light winds, and highly favorable
outdoor conditions.

By the weekend, a significant shift in the upper-level atmospheric
pattern takes place with high confidence as both deterministic
models and ensemble clusters exhibit strong consensus regarding the
amplification of a prominent upper-level ridge of high pressure
across the eastern half of the United States. Strong warm air
advection on the backside of the departing surface high will draw
seasonably warm air into Indiana. High temperatures are projected to
climb from the low 70s on Friday into the mid to upper 80s by
Saturday through Monday, which is well above normal for the middle
of May.

Daily storm chances will exist Friday into early next week as
individual disturbances set up along a quasi-warm frontal feature
stretching across the Plains and Great Lakes. While low confidence
exists in exact timing of placement of each wave, this type of
warm/hot and humid pattern does support daily storm chances with a
few severe storms not out of the question. Keeping PoPs at or under
50% for now and will adjust them accordingly as confidence increases
in the finer details. Not expecting a washout of a weekend, but
confidence is increasing in storms being in the vicinity .

&&

.AVIATION (18Z TAF Issuance)...
Issued at 227 PM EDT Tue May 12 2026

Impacts:

- Wind shift from SW to NW through the period
- SHRA late evening to overnight for most sites
- Southwesterly gusts up to 25kts through early morning

Discussion:

VFR conditions expected through much of the TAF period. Brief
lowered ceilings and visibilities to MVFR are possible as rain moves
through, but not enough to include in TAFs. Earliest chances for
rainfall look to be around 01Z at LAF with chances increasing
through 04Z. There may also be a few rumbles of thunder, but
confidence is too low to mention in the TAF. In addition to the
rain, can`t rule out a chance for sporadic LLWS as a strengthening
LLJ moves overhead. More so expecting gusts to 25 kt through the
early overnight hours. Rain chances then look to end towards 09Z.
Additional gusts to 25 kt likely tomorrow afternoon as well, this
time from the NW.


&&

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

$$

AVIATION...KF
DISCUSSION...CM