689
fxus63 kiwx 040546
afdiwx
area forecast discussion
national weather service northern indiana
146 am edt sat apr 4 2026
.key messages...
- more rain and storms are expected through today. heavy rain
is possible west of i-69 where a flood watch remains in
effect.
- severe storms capable of damaging straight-line winds are
possible east of i-69 this afternoon and early evening.
- cooler and drier weather returns sunday-wednesday.
&&
.discussion...
issued at 146 am edt sat apr 4 2026
our cwa is currently in a relative lull in activity as initial surge
of isentropic ascent and associated convection lifts e/ne. surface
warm front remains just south of our cwa and as expected, much of
the earlier activity remained elevated with just some small hail and
isolated heavy rain. better instability remains locked to our south
for now with easterly low level flow over our entire cwa. that will
change by later this morning though as upstream trough approaches
and southwesterly llj ramps up. surface warm front will begin
inching north around 08-09z but midlevel lapse rates are only around
6 c/km and even mucape values struggle to get much above 1000 j/kg.
surface warm front will also struggle to fully lift north until
after sunrise. expect showers and storms currently over il to
blossom and lift ne into our nw half after 08z but isolated heavy
rain will be the only real concern given relatively stable
conditions, particularly in the low levels. our nw cwa has the best
chance of seeing an inch or two of rain through the morning but
luckily this area missed out on the heavy rain the night of the
31st. still, isolated pockets of heavy rain and flooding will remain
possible roughly 08-14z and no changes to the flood watch planned.
attention then turns to the cold front set to swing through the area
later today. latest hi-res continued earlier trend of a slightly
slower frontal passage that would allow areas east of i-69 time to
destabilize. mlcape values climb to around 1500 j/kg with 30 kts of
0-6km shear. linear forcing, some modest dcape and strong,
unidirectional flow will favor damaging straight-line winds and
wouldn`t be surprised at all to see some impacts east of i-69 17-
23z. for areas west of i-69, conditions look to remain stable with
just some light-moderate rain at times through the day. not
expecting heavy rain but it won`t take much to cause problems given
extremely saturated soils and will therefore keep the watch going
until 5pm for now. later shifts may be able to trim or cancel once
the dust settles with morning rainfall.
rain exits our far se around 03z this evening and a welcome reprieve
from active weather sets up for early next week. much cooler
(seasonable) temps arrive tonight with a reinforcing shot of cold
air mon into tue. lows mon night dip well into the 20s and highs on
tue remain in the low/mid 40s. mainly dry conditions are expected
but sunday night into mon could feature some very light rain (maybe
even a few snowflakes) as a shortwave/cold front pass. some low
chances of rain arrive later next week as mid/upper flow flattens
and eventually returns to southwesterly. however, best chances
appear north of our area until next weekend, allowing time for
fields to slowly dry and river levels to recede.&&
.aviation /06z tafs through 06z sunday/...
issued at 130 am edt sat apr 4 2026
predominantly mvfr/ifr conditions at the terminals this period,
with breaks to vfr possible overnight. e-ne winds will shift
south through the morning, then become west-northwest by late
afternoon, early evening. the bulk of the precipitation is north
and east of the terminals, with the exception of some minor
showers just southwest of kfwa (near khhg/kmzz/kgus). guidance
re: evolution tonight is all over the place for both sites-with
some developing additional convection near the warm front (south
of kfwa) and lifting it north into ksbn, others mostly dry and
vfr until the cold front gets closer. ksbn is most likely to see
convection, however right now it`s focused just west and north
of the terminals. did bring in a tempo from 9-13z as the warm
front lifts into the area and the cold front is just to the
northwest near lake mi. at kfwa- most guidance remained vfr/mvfr
through the overnight, but current observation suggests around
600-800ft. have a tempo for now, as i`m not certain how long
this will persist. most of the surrounding sites are mvfr/vfr.
have a prob30 from 9-12z for potential convection along the
front as it approaches, but it may end up being showers and
perhaps some br/fg (some models drop to 1/2sm at times, but left
out for now given uncertainties). the cold front moves through
tomorrow afternoon/evening for kfwa, and this morning/early
afternoon for ksbn-which will bring a more steady period of
heavy rain and scattered thunderstorms (especially at kfwa given
it`s arriving in peak heating).
&&
.iwx watches/warnings/advisories...
in...flood watch through this afternoon for inz005>009-012>015-017-
018-103-104-116-203-204-216.
oh...none.
mi...flood watch through this afternoon for miz078>080-177-277.
marine...none.
&&
$$
discussion...agd
aviation...mcd