650
FXUS63 KIWX 041842
AFDIWX

Area Forecast Discussion
National Weather Service Northern Indiana
242 PM EDT Thu Jul 4 2024

.KEY MESSAGES...

- Chances for showers and thunderstorms persist into Friday,
  with locally heavy rain the main concern.

- More comfortable humidity levels this weekend, with only
  limited chances for showers Saturday.

- Somewhat better shower and thunderstorm chances return Monday
  into Tuesday.

&&

.DISCUSSION...
Issued at 238 PM EDT Thu Jul 4 2024

While high confidence exists on a relatively active pattern, finer
details continue to have much lower confidence due to difficulty in
timing and location of key features. Forecast emphasis will be
on the next couple of days with few overall changes expected for
the later periods.

Diffuse frontal boundary was located from southern IL to north of
IND and then towards NW Ohio. Area of light to occasionally moderate
rainfall worked north across much of the area, but a slow weakening
trend occurred as it moves away from the front and best LLJ
position. Heavier rain and thunderstorms remained south of the area
across central/southern Indiana associated with a weak disturbance.
Although earlier CAMs suggested a bit more robust development
possible late this afternoon into early evening, they seem to have
backed off, maybe as a result of the more extensive coverage of the
precip the first part of the day. MCV was working into southern IL
and will continue east, likely being the main focus for
additional development later today south of our area. With the
front in the area and pockets of heating, mainly SE, can`t rule
out some additional showers/storms popping that would produce
mainly locally heavy rain. Pockets of clearing upstream across
central IL are allowing for some new shower development. Models
seem to suggest after 3Z little or no chance for development
until maybe closer to Fri morning as the main trough begins to
edge in to western areas. Pops also adjusted accordingly with
any likely mention overnight removed. Lift from the front and
plenty of moisture around should allow for isolated to maybe
scattered showers/storms through late Friday afternoon along and
ahead of the front. Shear parameters aren`t bad as is some
cooler air aloft. However, better severe chances should remain
east of the area.

Bulk of the weekend could end up dry with maybe just a few light
showers Saturday as the main trough pushes NE and heights increase
somewhat before the next trough early next week. Some models show a
weak disturbance Saturday that could still bring a few showers, but
CAMs don`t seem overly impressed at this point. Typical early July
temps can be expected with highs in the low to mid 60s with
dewpoints remaining in the mid to upper 50s, making for a
comfortable holiday weekend.

Next deeper trough edges toward the region late Monday into Tuesday
with chances for showers and storms increasing with this feature.
Moisture return will occur ahead of the trough, but conservative chc
pops will be maintained at this point.


&&

.AVIATION /18Z TAFS THROUGH 18Z FRIDAY/...
Issued at 200 PM EDT Thu Jul 4 2024

Area of showers and storms will continue to decay through mid-
late afternoon with the heavier showers through 21Z expected
east of the terminals across Ohio. A remnant convectively
enhanced short wave across northwest Indiana could be a trigger
for additional scattered showers/isolated thunderstorms late
afternoon into evening, but this potential appears to maximized
south and southeast of KFWA. Will carry TEMPO SHRA mention at
KFWA this evening, with greater potential of thunder south of
KFWA given strong instability gradient across central Indiana.
Showers should diminish late evening. Another more significant
short wave trough will approach the western Great Lakes toward
the end of this period. A band of rain showers may affect the
terminals from west to east in 12Z-18Z time period on Friday,
with isolated to scattered showers and thunderstorms possible on
Friday afternoon as cold front approaches. Confidence is low on
thunder coverage Friday afternoon however, as frontal
convergence appears to be rather weak. Mainly VFR conditions are
expected this period, but a brief period of MVFR cigs is
possible Friday morning.

&&

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

&&

$$

DISCUSSION...Fisher
AVIATION...Marsili