154
fxus63 kiwx 311017
afdiwx
area forecast discussion
national weather service northern indiana
617 am edt sat oct 31 2026
.key messages...
- light rain showers this morning gradually move out by the mid
afternoon.
- very warm on tuesday followed by increasing rain chances
through wednesday (60% chance).
&&
.discussion...
issued at 337 am edt sat oct 31 2026
an area of showers is underway spanning from central ia through
extreme western indiana. mesoanalysis shows warm air advection aloft
along with subtle near-surface convergence, and even modest elevated
instability (through central il, fading well before the in line).
this waa and surface convergence lift north-northeast through early
this afternoon. despite an 8,000 foot dry layer and a 10-degree dew
point depression, light rain is underway at monticello, in. trends
lead me to believe these showers will persist through at least the
morning hours. the centroid of high pressure is analyzed over the
greater lansing area, suggesting the far northeast reaches of these
showers will be limited, battling additional dry air and subsidence.
will carry on with the continued halloween message of isoalted
showers, especially in the morning. it does appear showers will
move out in time for trick-or- treat hours. cloudy and somewhat
cool with highs just beyond 60 degrees.
murky, spotty, and weakly forced shower chances linger through at
least monday as high pressure gradually gives way to ridging ahead
of deepening low over the central us. this results in periods of low-
confidence 20-30% pops. a weak shortwave moving through the oh river
valley presents a 20% chance of showers for far southern reaches of
the forecast area sunday afternoon, with perhaps a better moisture
stream arriving overnight.
the primary item of interest in the extended forecast is the mid-
latitude cyclone moving through midweek. very warm on tuesday (near-
record highs) ahead of this low as the jet stream becomes highly
amplified over the midwest. breezy with southerly wind gusts of 20-
25 mph. the occluding low over far northern lower michigan looks to
delay our best rain chance until late tuesday night and wednesday.
how cyclogenesis evolves over the mid-mississippi thereafter
dictates how much our rain will see, or whether the cold/occluded
frontal passage is our only chance for rain. behind the low, still
mild for early november with highs in the 60s and lows in the
40s.
&&
.aviation /12z tafs through 12z sunday/...
issued at 612 am edt sat oct 31 2026
latest tafs account for an area of warm advection rain that has
persisted all morning. upstream observations strongly support
this activity is vfr in nature. the end time offers medium
confidence as model guidance is gradually acknowledging these
showers. cannot completely rule out more showers early sunday
morning with a shortwave passing through the ohio valley.
&&
.iwx watches/warnings/advisories...
in...none.
oh...none.
mi...none.
marine...none.
&&
$$
discussion...brown
aviation...brown