180
FXUS63 KIND 021025
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
625 AM EDT Sat May 2 2026

.KEY MESSAGES...

- Below normal temps to continue through the weekend with frost
  likely this morning and possible Sunday morning

- Milder but still largely below normal next week, with multiple
  chances for rain; heavy rain possible at times

&&

.DISCUSSION (Today through Friday)...
Issued at 304 AM EDT Sat May 2 2026

The general synoptic pattern will be rather stagnant over the next 7
to 10 days as a broad trough remains over Eastern Canada. The impact
to central Indiana will be a cooler than normal pattern with
temperatures peaks near seasonal and temperature valleys 10 to 15
degrees below normal.

For today, a significant dip in the aforementioned trough will keep
the much below normal temperatures across the region, signified by
850mb temperatures between -2 and -4C. Ahead of this dip will be
weak ascent, leading to broken cloud cover and very light rain
showers, mostly over SW portions of the region this morning.
Building pressure behind the trough axis late today and tonight
should aid in skies clearing leading to another night with frost
potential. Current expectation is for a bulk of the frost risk to be
over eastern portions of the state (closer to the trough axis and
cooler 850mb temps), but there is some uncertainty on how wide
spread this frost will be, mostly due to a consistent, but weak
surface wind. The daytime on Sunday will likely be partly to mostly
cloudy as a weak vort max pivots around the larger Canadian trough.
Some guidance is showing enough lift through a saturated 850-700mb
layer for light showers, and so PoPs have been increased across
northern central Indiana for Sunday afternoon and evening.
Regardless of this, any rain will be weak with QPF values less than
0.1".

The previously discussed temperature peaks will mostly reside ahead
of positively tilted shortwaves as ridging attempt to push in from
the west, the first of which will be Monday and Tuesday.
Temperatures will likely reach above seasonal for a brief period on
Monday as a narrow corridor of strong WAA ahead of the wave
coincides with peak diurnal warming; current expectation is for
Monday`s highs to be in the mid 70s. Confidence is high that there
will be precipitation over the Ohio Valley Late Monday through
Tuesday as the wave passes through, but there is still ensemble
spread on the precipitation axis, and therefor confidence in
location specific QPF is relatively lower. Initially, rain will
likely be associated with frontogenetical banding on Monday night,
but should transition to surface based convective processes
throughout Tuesday. There is some risk of hail on Monday night
within frontal convection due to modest lapse rates above the PBL,
but the severe risk looks low on Tuesday with lapse rates nearing
moist adiabatic and the upper level support not properly phased to
optimize shear.

As the upper level support arrives late Tuesday through Wednesday,
surface pressure falls across the southern Ohio Valley will likely
reinforce lift across central Indiana leading to additional rain
chances. Given the greater mid level lapse rates and mid-level shear
on Wednesday, stronger thunderstorms within elevated convection will
be possible despite greater near surface stability.

&&

.AVIATION (12Z TAF Issuance)...
Issued at 624 AM EDT Sat May 2 2026

Impacts:

- Gusts of 20kt tomorrow afternoon

Discussion:

Isolated showers will continue to pass through this morning
mainly SW of all sites. Showers cannot be completely ruled out at
KBMG, but probability is less than 30 percent so it was left out
of the TAF.

A broken to scattered deck of stratocumulus is expected to remain
through the morning and early afternoon at around 5000ft. Mid level
clouds will dissipate throughout the afternoon, with only passing
cirrus expected this evening and tonight.

Winds will shift slowly today from NE to NW but remain below 10kt.
Tonight winds will shift towards the SW, and remain out of the SW
tomorrow. Gusty winds are likely in the afternoon tomorrow, peaking
around 20kt.

&&

.IND WATCHES/WARNINGS/ADVISORIES...
Frost Advisory until 9 AM EDT this morning for INZ021-028>031-
035>049-054>057-065.

&&

$$

AVIATION...Updike
DISCUSSION...Updike