840
FXUS63 KIWX 031825
AFDIWX

Area Forecast Discussion
National Weather Service Northern Indiana
225 PM EDT Wed Jul 3 2024

.KEY MESSAGES...

- Along and south of US 24 today, there is a Marginal Risk
  (level 1 of 5) for a few strong to severe storms between now
  and 8 PM EDT. Damaging wind gusts and heavy rain are the main
  threats.

- Additional chances for showers/thunderstorms persist through Friday.
  Isolated to scattered showers and storms will be possible in
  the afternoon/evening on the 4th of July and again during the
  day on Friday. Warm and humid with highs in the mid 80s.

- Dry conditions and near normal temperatures for the weekend.
  Near normal temperatures look to stick around for much of next
  week (highs mid 80s, lows mid 60s) with sporadic, low chances
  for rain/storms. The best chances for rain/storms will be on
  Tuesday.

&&

.DISCUSSION...
Issued at 224 PM EDT Wed Jul 3 2024

Warm and humid conditions have returned as a warm front lifted north
through the area overnight. A weak cold front is currently entering
our area, with showers/storms possibly developing out ahead of it
this afternoon and early evening. There is a Marginal Risk for
severe weather (level 1 of 5) along and south of US 24. A few storms
could be strong to severe, with damaging wind gusts and heavy rain
as the primary threats. Storm coverage should be isolated to
scattered at best. I would not be surprised if SPC chooses to
pull the Marginal Risk entirely from our area as there is very
low confidence in storms reaching severe criteria. Model
guidance continues to trend with less instability (500-1000
MLCAPE) this afternoon, and low/mid level lapse rates are sub-
par amidst only 20 to 30 knots of 0-6 km shear to work with. If
the RAP is correct, there also could be an EML to work with this
afternoon that caps any storm development.

There are additional chances for rain/storms for the Fourth of July
and again Friday. As a surface low lifts northeast across Missouri
Thursday evening, the attendant warm front will lift north through
our area. This could result in some rain/storm chances for Thursday
evening, although I`ve kept the highest chances (30-40%) confined to
along and south of US 30 for now. These PoPs will likely need
adjusting in subsequent forecast updates as we get more
certainty as to how far north the warm front gets. Should the
boundary stall across our area, this would lead to lingering
showers/clouds overnight Thursday into Friday morning. Friday`s
rain/storm chances are conditional to what happens Thursday;
should any clearing occur Friday morning, there would be chances
for rain/storms to redevelop again late morning through the
afternoon on Friday along a cold front. I would not be surprised
if SPC adds us into a Marginal Risk on Friday given the
favorable parameters for severe weather, especially on the NAM
and NAMNST. Soundings midday Friday from the NAMNST depict an
unstable environment with 2000+ J/kg MLCAPE, 40 kts of shear,
and moderately steep low and mid level lapse rates.

For the weekend, dry conditions, comfortable humidity, and cooler
temperatures return! Saturday will be the cooler day of the weekend
with highs in the mid 70s. Next week, the latest CPC outlook has
near normal temperatures favored (which would mean highs in the low
80s, lows in the mid 60s), which is somewhat unusual for mid
July. There has been a pretty consistent signal in model
guidance the past few days that next week will be near normal
for temperatures with sporadic, low chances for rain/storms.
There are no consistent signals for high heat to return until
possibly 10 to 14 days from now.

&&

.AVIATION /18Z TAFS THROUGH 18Z THURSDAY/...
Issued at 137 PM EDT Wed Jul 3 2024

A weak surface cool front will continue to make its way across
northeast Indiana this evening. Locations in vicinity of this
front have experienced MVFR cigs around 2k feet for much of the
afternoon, and expecting continued improvements in these cigs
with peak diurnal mixing. A few showers appear to be developing
along this frontal boundary across far NW Indiana, but would
expect focus to remain south of KSBN. A more concentrated area
of scattered shower/isolated storm coverage extends from KIND
to KMIE to KAOH in pre-frontal zone. This area is along a better
instability gradient and may continue to be a focal point for
showers and storms into this evening. KFWA may be situated
between these two preferred areas of forcing, but some scattered
showers are possible at KFWA from 20Z-00Z as weak cold front
drops into northeast Indiana. Instability will be more limited
at KFWA in comparison to east central Indiana, and confidence in
thunder coverage is low. Low confidence also persists in how
long isolated shower potential will continue into this evening,
but potential should wane after 00Z. Some patchy fog and stratus
may develop tonight, but greater potential appears to be south
of KFWA.

&&

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

&&

$$

DISCUSSION...Johnson
AVIATION...Marsili