414
FXUS63 KIWX 030957
AFDIWX

Area Forecast Discussion
National Weather Service Northern Indiana
457 AM EST Mon Nov 3 2025

.KEY MESSAGES...

- Sprinkles are possible along and north of the Toll Road this
  morning but otherwise dry conditions prevail through Thursday.

- Gusty winds are expected this afternoon and low relative
  humidities could allow any fires to spread out of control.
  Exercise caution if planning to burn leaves today.

- Highs this week will remain in the upper 50s to mid 60s.
  Widespread light rain finally returns on Friday.

&&

.DISCUSSION...
Issued at 306 AM EST Mon Nov 3 2025

Potent upper jet (300mb winds near 175 kts) is currently digging
into the Great Lakes and driving a fairly deep PV anomaly (1.5 PVU
surface to 500mb) through the northern Lakes on its cyclonically
sheared side. This places the right exit region squarely over our
CWA though and thus unfavorable for ascent/precip. Strong SW flow to
the south of this jet streak/trough is generating some minor
moisture convergence capable of spitting out a stray sprinkle in our
far northern zones during the morning hours. Have added a
sprinkle mention but overall no impact. Main impact may end up
being some gusty winds today. Deep mixing (to almost 800mb in
spots) and a tight gradient will generate gusts up to 30 kts
from late morning through early afternoon. Also of some concern
is the extremely dry air advecting in behind the "cold" front
this afternoon. Surface dewpoints drop into the 20s and could
lead to some fire wx concerns while winds remain gusty during
the afternoon. RH values of 30-40 percent are well shy of red
flag criteria but some spots in the SW could briefly drop below
30 percent and anyone planning to burn leaves later today should
exercise caution, especially given the lack of rainfall
recently. Highs today make a run at 60 given full afternoon sun
and deep mixing.

A similar system arrives early Wed. This system is a bit weaker from
a jet dynamics perspective but tracks a bit further south and
features much better postfrontal CAA. Suspect dry conditions will
prevail but here again can`t entirely rule out a sprinkle across the
north. Ahead of this system, steady WAA will push highs to around 60
on Tue and well into the 60s on Wed (67 south). Modest CAA brings us
back to reality for Wed night/Thu but still not bad for Nov. The
next good chance of rain finally arrives on Fri morning as moderate
amplitude trough swings directly overhead and taps into good
prefrontal theta-e return (by Nov standards). Widespread rain
appears likely though perhaps not for a long duration given speed
and orientation of this system. Still looks like a solid quarter
inch with up to a half inch possible. Thunder not out of the
question but will hold off on including for now given poor diurnal
timing and lackluster MUCAPE values. Minor CAA expected for Sat but
it looks increasingly likely that a second system develops early Sun
that eventually draws some much colder air into the region late Sun
into Mon of next week. Deterministic models in surprising agreement
this far out though ensembles do still show some spread. If this
holds, 850mb temps slated to drop to -10C which will assuredly bring
some lake effect snow to the region.

&&

.AVIATION /12Z TAFS THROUGH 06Z TUESDAY/...
Issued at 446 AM EST Mon Nov 3 2025

A trof of low pressure extended across WI into a deep low
pressure area near James Bay. Southwest flow was over northern
Indiana, ahead of a trof of low pressure. Light showers ranged
from northern Indiana, across southern Lake Michigan into
southern WI. The precipitation was falling from mid based clouds
(around 10,000 feet). Few if any visibility restrictions were
indicated by surface reports upstream over northern IL. The
tight pressure gradient will bring gusty winds to the terminals
today, with wind gusts approaching 30 knots. The deep low will
move rapidly east and cause southwest winds to shift to the
west and northwest later today. The lower layers remained quite
dry and moisture was generally limited, but a brief shower is
possible early in the TAF period; otherwise, some mid clouds
will prevail with dry weather. Winds should diminish toward
sunset as the atmosphere decouples.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...None.
OH...None.
MI...None.
MARINE...Small Craft Advisory until 4 AM EST Tuesday for LMZ043-046.

&&

$$

DISCUSSION...AGD
AVIATION...Skipper