Grand Detour Illinois Weather Forecast Discussion

218
FXUS63 KLOT 120700
AFDLOT
Area Forecast Discussion
National Weather Service Chicago/Romeoville, IL
200 AM CDT Sun Oct 12 2025
.KEY MESSAGES...
- Other than the potential for a few light showers late Tuesday
  (20-30% chance), mainly dry and seasonable conditions are
  expected the next several days.
- The pattern turns more active late week with increasing rain
  chances (30-40%).
&&
.DISCUSSION...
Issued at 200 AM CDT Sun Oct 12 2025
Today will be dry with high temperatures in the lower 70s for
much of the area. Southeast winds may gust into the 20 mph range
for areas north of I-80 this afternoon and these southeast winds
will keep temps in the mid/upper 60s for far northeast IL and
along the IL Lake Michigan shore.
A weak upper wave will move toward the area overnight into
Monday morning, bringing a chance for showers across northeast
IA and southwest WI. The low levels remain very dry ahead of
this feature and expect whatever precipitation does develop west
of the local area to dissipate before arriving overnight with
perhaps some virga or sprinkles. The low levels do saturate some
by mid/late morning Monday, but by that time, there isn`t much
forcing for showers. It is possible some slight chance pops or
sprinkle mention will be needed with later forecasts, especially
for northwest IL, but opted to stay dry with this forecast. High
temps on Monday will likely be a few degrees warmer than today,
in the lower/mid 70s for most locations.
A cold front will move south across the area Monday night with
winds turning northeasterly for Tuesday/Wednesday and cooler
temps. Models show another disturbance moving across the
midwest Tuesday afternoon through Wednesday morning bringing a
chance of showers to the area, especially along and north of
I-80. As the current 00z models appear in better agreement with
this possibility, the blended pops have gone down to just slight
chance for early Wednesday morning. With this time period still
a few days away, made no changes and trends will need to be
monitored.
Still quite a bit of uncertainty for how the pattern will evolve
late this week into next weekend, but it still looks active with
increasing precipitation chances. cms
&&
.AVIATION /06Z TAFS THROUGH 12Z MONDAY/...
Issued at 1159 PM CDT Sat Oct 11 2025
There are no significant aviation weather concerns anticipated
through the period.
The area of cloud cover across northeastern IL persisting
through much of the evening has finally begin to shift
northwestward and dissipate. While a brief (hour or so) BKN CIG
around 3,000 feet could materialize at KRFD prior to 07Z, it
appears the majority of this cloud cover will be north in WI.
Otherwise, VFR conditions are expected through the period with
only some higher level cloud cover expected later today into
tonight.
Expect winds to remain east-southeastly today, with speeds up
around 10 kt during the daylight hours.
KJB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...None.
IN...None.
LM...None.
&&
$$
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NWS LOT Office Area Forecast Discussion