537
fxus63 kiwx 310740
afdiwx
area forecast discussion
national weather service northern indiana
340 am edt sat oct 31 2026
.key messages...
- 20% chance for isolated showers or sprinkles today,
especially west of i-69. plenty of dry hours otherwise.
little, if any impacts expected for halloween evening.
- 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 mainly west of i-69 (20% chance). plenty of dry time
otherwise of halloween, especially for late-afternoon 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 /06z tafs through 06z sunday/...
issued at 1247 am edt sat oct 31 2026
existing tafs are on track at this time. wind takes on a more
south-southeasterly direction later this morning at kfwa.
otherwise, no significant changes.
an area of rain over southeast ia is poorly modeled this hour.
mesoanalysis indicates this activity is the result of modest
850-mb waa and subsequent theta-e advection, along with a narrow
axis of elevated instability. these features are forecast to
seep northeast through il today and will be monitored for
anything beyond prob30 -shra at ksbn. high confidence in dry
conditions at kfwa.
&&
.iwx watches/warnings/advisories...
in...none.
oh...none.
mi...none.
marine...none.
&&
$$
discussion...brown
aviation...brown