325
FXUS63 KIWX 141707
AFDIWX

Area Forecast Discussion
National Weather Service Northern Indiana
107 PM EDT Sat Jun 14 2025

.KEY MESSAGES...

- Rain showers gradually diminish in coverage through the day.

- Turning warmer early next week with highs well into the 80s.

- Next chance of greater coverage showers and thunderstorms
  arrives by Wednesday.

&&

.DISCUSSION...
Issued at 333 AM EDT Sat Jun 14 2025

An upper level trough cut off from the main belt of westerlies
across the Northern Plains and Great Lakes region has been
attempting to lift northeast but is encountering a confluent flow
regime across the southern Great Lakes. As this wave shifts across
the Ohio Valley today, it should continue to open and become more
sheared in nature due to the influence of this background flow. A
downstream reflection of this wave has materialized in the form of
an elongated southwest to northeast sfc trough. This trough may make
some slight northward advancement through daybreak, but should tend
to anchor in vicinity of US Route 24 corridor for a time. Low level
level moisture convergence associated with this trough axis and
stationary nature to this trough axis could promote some pockets of
heavier rainfall (isolated 1 to 2.5" inches) across northeast
Indiana and northwest Ohio roughly along US Route 24 corridor. This
will likely be in the form of some minor flooding/ponding of water
on roadways. Impressive warm cloud depths of around 12k feet,
anomalous PWATs of 1.75+ inches. and stationary nature tA stationary
front was south of FWA. The front will try to move north as a
wave tracks east along the front. Have keep winds ENE north of
the front at both TAF sites. Ceilings will fall below 010 into
the IFR category and will be slow to lift. Blended some high res
guidance along with currents obs & trends with conditional
climatology. o low level trough axis are conducive for isolated
heavy rainfall potential. A few negative factors include the
dampening nature to the upper wave, stronger dynamic forcing
remaining south of the area, and overall weak low level wind
fields with a modest 20 knot southerly low level jet supporting
only weak to moderate low level moisture convergence. A weak
surface wave along this trough axis will eventually shift into
west central Ohio this afternoon resulting in a tapering of rain
shower potential from northwest to southeast.

Poor mixing today raises the concern that low clouds will be hard to
erode across the area. Thus, some lower than normal confidence in
max temp forecast today with a possibility that a few areas across
northwest Ohio into far northeast Indiana could struggle to reach
70. Some slightly better mixing is possible far northwest areas
later in the afternoon that could aid in high reaching into mid 70s.

Quiet conditions are expected tonight, with main item of uncertainty
on low cloud evolution across southeast half of the area. Low level
northeast flow on western periphery of the dampening mid level
trough could allow for some low cloud redevelopment/maintenance
across northeast Indiana/northwest Ohio as some slightly better
low level moisture advects westward.

Sunday should feature warmer conditions as some short wave
upper ridging builds across the southern Great Lakes with better
insolation in comparison to today. This should yield highs in
the lower 80s most areas, although weak onshore flow could
result in some cooler conditions for immediate lakeshore areas
across southern Lake Michigan.

For early work week, guidance has been consistent in a slow moving
upper wave progressing across the Great Lakes region on Monday, but
moisture quality looks questionable for early week which argues for
maintenance of just some slight chance PoPs across the west. By
Tuesday, indications persist that westerly low level flow will
become a bit more pronounced but thunder chances locally may be
dependent on convective modification of upstream smaller scale
disturbances which has low predictability at this forecast distance.
Thus, will maintain just some mid range chance PoPs Tue-Tue night.

The middle of the week is still shaping up as the potential best
chance of greater coverage showers and thunderstorms as a stronger
eastern Pacific jet streak induces a stronger upper PV anomaly
emerging in the lee of the Rockies. The potential exists for a good
moisture transport feed from the southern Plains preceding this wave
with a possible pre-frontal forcing focus on Wednesday
afternoon/evening. Have made little change to likely shower/storm
PoPs for later Wednesday. This still looks to be a period to watch
for a potential of strong to severe storms depending on timing of
these forcing mechanisms.

Medium range guidance is in general agreement regarding mid level
height rises in wake of this upper trough for late work week, but
vary significantly in timing of the amplification of the ridge.
Overall pattern does seem to support the potential that a decent
instability gradient will be positioned across the region and have
broadbrushed latter periods with slight chance shower/storm PoPs. Of
somewhat greater confidence is the trend to above normal
temperatures toward the end and just beyond this forecast valid
period as the upper ridge axis shifts to the eastern Great
Lakes.

&&

.AVIATION /18Z TAFS THROUGH 18Z SUNDAY/...
Issued at 102 PM EDT Sat Jun 14 2025

Showers associated with a slow-moving low pressure system have
notably diminished in coverage this morning but a couple
lingering showers remain near KFWA. This activity will cease
shortly with any redevelopment favored off to the southeast
prior to sunset. Otherwise, at both sites, a gradual improvement
of ceilings is expected. Satellite shower rapid clearing
underway near KSBN. At KFWA, improvement to VFR is plausible
prior to 00z should the clearing continue to advance rapidly
southeast. For now, held close to the existing forecast. Time
height cross sections suggest SCT low-level clouds overnight
with the lows associated stationary front hung up through
central IN.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...None.
OH...None.
MI...None.
MARINE...None.

&&

$$

DISCUSSION...Marsili
AVIATION...Brown