280
FXUS63 KIWX 020725
AFDIWX

Area Forecast Discussion
National Weather Service Northern Indiana
325 AM EDT Sun Jun 2 2024

.KEY MESSAGES...

- Drying out Sunday with slowly decreasing clouds.

- Frequent chances of showers and thunderstorms beginning Monday
  night.

- After a warm start to the week, it will be notably cooler by
  week`s end.

&&

.DISCUSSION...
Issued at 307 AM EDT Sun Jun 2 2024

A weak cold front is working its way through Michiana early this
morning. This feature is most visible on radar as a fine line of
showers. Behind this, dew points are falling to the 50s paired with
a northerly wind. This feature is forecast to track southeast,
likely washing out by the afternoon as ridging resumes aloft.
Otherwise, showers are departing northwest Ohio at this time
thus promising a mainly dry Sunday for the area. I say "mainly"
not only for the aformentioned fine line of showers, but because
we`ve noted intermittent drizzle at the office. This patchy
drizzle is forecast to end in the wake of the cold front.
Lastly, fog is noted in upstream observations, primarily across
the Mississippi River. This airmass arrives overhead tonight
such that fog could be a concern. Guidance is split at this
moment, so, will pass this concern to the incoming shift.

Dry weather prevails through the day Monday, amid weak zonal
flow aloft and high pressure arriving in the wake of Saturday`s
rain- maker. Over the Northern Plains on Monday, thunderstorms
are forecast to develop in the vicinity of a cold front. These
storms drift east into Illinois late in the day. This change in
timing, thanks to lingering high pressure and weak flow aloft,
has allowed me to remove POPs Monday afternoon. The chance for
showers and storms remains in the forecast after sunset,
however, but coverage is questionable. WFO Chicago and I worked
to reduce POPs during that time frame.

Convection amid weak zonal flow offers low confidence in the
coverage of showers and storms Tuesday. In the meantime, I held
close to the inherited forecast which follows a subtle diurnal curve
in POP coverage.

Following this, a deep cut-off low plagues the forecast Wednesday
through the end of the week. This will bring widespread showers and
thunderstorms Wednesday, followed by cooler temperatures. As spokes
of vorticity revolve around the low in the days that follow, off and
on showers are nearly guaranteed. Coverage is uncertain here as
well, thus POPs near 20% litter the late-week forecast.
Observed high temperatures from Monday and Tuesday in the 80s
will give way to highs in the low-70s both Friday and Saturday.


&&

.AVIATION /06Z TAFS THROUGH 06Z MONDAY/...
Issued at 125 AM EDT Sun Jun 2 2024

Weak low pressure system is currently moving across the area and
will continue to support IFR/LIFR conditions through the early
morning. Latest guidance...supported by upstream obs...indicates
potential for LIFR ceilings and visibilities at KSBN in the
09-14Z window as winds veer northwesterly and advect very moist
conditions currently over Lake MI into the area. Dense fog
appears unlikely but many upstream obs show 1SM BR and 200ft
ceilings. Higher moisture content is unlikely to reach KFWA
before diurnal heating kicks in but ceilings will remain IFR and
could drop to 400ft at times through the early morning.
Conditions slowly improve by the afternoon with VFR expected
after 18Z. Confidence in exact timing of transitions to MVFR and
VFR remains low however.

&&

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

&&

$$

DISCUSSION...Brown
AVIATION...AGD