378
FXUS63 KIWX 012322
AFDIWX

Area Forecast Discussion
National Weather Service Northern Indiana
722 PM EDT Thu Oct 1 2026

.KEY MESSAGES...

- Rain and isolated thunderstorms this evening through mid-
  morning Friday. Rainfall totals on either side of 1 inch.

- Notably cooler Friday through the weekend with highs in the
  60s.

- Very crisp Tuesday morning with lows in the 30s (70% chance).

&&

.DISCUSSION...
Issued at 202 PM EDT Thu Oct 1 2026

Warm, breezy, with increasing clouds for the remainder of the day
followed by rain and isolated thunderstorms as a cold front sags
southeast. Excellent moisture return from the Gulf is evident on
water vapor, as anticyclonic flow off a southeast US ridge funnels
moisture poleward against a low swirling over the OK Panhandle.
Forecast soundings overnight depict an impressive warm-cloud layer
of 12,000 ft, indicative of a moisture-rich atmosphere. Boundary-
parallel flow through the column will limit the front`s forward
speed. As a result, fairly high confidence in rainfall amounts
tonight through late-morning Friday on either side of 1". Some high-
resolution ensembles have a few stripes of 2" totals which is
certainly possible from any isoalted thunderstorms that bubble up.
Yet overall, with 10-day observed rainfall of less than 0.50", the
general feeling is that the forecast area can handle this rainfall.
We can address any near-term flood concerns with Flood Advisories as
needed.

Circling back to thunder for a moment, the best time for an isoalted
thunderstorm is from about 4pm to 10pm EDT when a narrow ribbon of
instability is maximized; still shy of 1,000 j/kg. Tonight`s rain
looks to be primary rain event for the next seven days. Low pressure
through Ontario threatens to bring showers Sunday to central and
northern Michigan, while a second system takes a similar path late
next week.

Sharply cooler behind the front resulting in highs Friday through
the weekend only in the 60s with Canadian high pressure moving in.
As mentioned here this morning, Tuesday morning looks absolutely
crisp with lows in the 30s. Advertised lows could be 2 to 3 degrees
on the cold side of available guidance (shy of the 25th percentile),
but within the realm of possibility. Fear not, as temperatures appear
poised to rebound late in the week as upper-level troughing moves
east.

&&

.AVIATION /00Z TAFS THROUGH 00Z SATURDAY/...
Issued at 722 PM EDT Thu Oct 1 2026

Cold front slowly progressing across the area and will bring
widespread moderate rain overnight. IFR ceilings are likely for
much of the overnight period based on latest guidance and
upstream obs which show ceilings around 500ft. A stray
thunderstorm can`t be entirely ruled out at KFWA but chances are
too low to include in the TAF. Rapid improvement expected Friday
morning with return to VFR and clearing skies by the afternoon.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...None.
OH...None.
MI...None.
MARINE...Small Craft Advisory from 8 AM to 11 PM EDT Friday for LMZ043-
     046.

&&

$$

DISCUSSION...Brown
AVIATION...AGD