Tinley Park, Illinois 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

424
FXUS63 KLOT 250530
AFDLOT

Area Forecast Discussion
National Weather Service Chicago/Romeoville, IL
1230 AM CDT Mon May 25 2026

.KEY MESSAGES...

- Fog development is possible early this morning near the
  immediate Lake Michigan shore as well as inland areas east of
  I-57, some of which could become locally dense.

- Above normal temperatures favored through next weekend, though
  cooler near Lake Michigan. Rain chances appear low during this
  period, with chances for showers and storms confined to
  Wednesday.

&&

.DISCUSSION...
Issued at 144 PM CDT Sun May 24 2026

High pressure centered just west of the area this afternoon
will drift overhead tonight, setting the stage for light/calm
winds as skies remain primarily clear. With some (potentially
dense) fog already evident over Lake Michigan in the wake of
today`s rain, will need to closely monitor trends late this
afternoon and especially this evening along the Illinois shore
as backing low-level flow would then begin advecting any fog
onshore. Additionally, patchy shallow fog is possible overnight
where rain was more prevalent (around and east of I-55) today.
And while low-level will begin veering SSW later tonight subtle
WAA acting on any shallow fog south of I-80 would start
advecting northward toward the Chicago metro around sunrise. Any
shallow fog will quickly dissipate after sunrise.

A small wave/complex of convection over Nebraska and South
Dakota late today will drift toward southern Wisconsin and far
northern Illinois Monday morning and early afternoon. The
thermodynamic environment will become increasingly unfavorable
with eastward extent across Iowa and especially east of the
Mississippi River. Expectations are for some mid-level clouds
and perhaps a few rogue sprinkles in the far northwest CWA
midday.

A massive Hudson Bay high developing ahead of a highly
amplified ridge over the central/northern Great Plains into
central Canada will drift southward midweek into next weekend.
Guidance remains mixed on how far north a southwestern CONUS
trough becomes cutoff over the southern Great Plains or Lower
Mississippi Valley this week. Latest indications are that a vast
majority of moisture/forcing associated with the cut off system
will remain south of the area, with the exception of a backdoor
front bringing a period of showers and some storms to the area
Wednesday. Otherwise, dry conditions and seasonably warm
temperatures (cooler near the lake) would be expected through
much of the period.

Kluber

&&

.AVIATION /06Z TAFS THROUGH 12Z TUESDAY/...
Issued at 1230 AM CDT Mon May 25 2026

Key Aviation Messages for the current TAF period:

- Localized vis reductions from fog closer to the lake this
  morning, but confidence is low.

Mostly VFR and dry conditions are expected through the current
TAF window. The only exception is localized fog in northern
Indiana and over the lake that may ooze inland. Confidence in it
reaching any specific terminal is low, and may just reduce
things to 5 or 6 SM with some BCFG, but will be monitored
closely. The only other impact to terminals are wind direction
trends. Everything is light and southeasterly currently and
expected to flip to the southwest after daybreak. A lake breeze
is expected in the afternoon switching things to the southeast.
Winds will diminish this evening and become more southerly if
not southwest.

DK

&&

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...None.
IN...None.
LM...None.

&&

$$

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