Weavers Weather

179
FXUS63 KLOT 202337
AFDLOT

Area Forecast Discussion
National Weather Service Chicago/Romeoville, IL
637 PM CDT Fri Mar 20 2026

.KEY MESSAGES...

- Unseasonably mild spring-like temperatures continue through
  Saturday.

- Much cooler weather returns with a cold front on Sunday, and
  persists into early next week.

&&

.DISCUSSION...
Issued at 147 PM CDT Fri Mar 20 2026

A cold front continues to work southward across the area early
this afternoon. However, with the lack of a real cold push in
its wake, conditions remain unseasonably mild (mid 60s to the
70s) area-wide early this afternoon. However, this will change
for areas near Lake Michigan later this afternoon as the low-
level flow flips onshore with a lake breeze. As this occurs
after 2 or 3 this afternoon, temperatures will quickly drop off
into the 40s and 50s, coldest along and near the lakeshore.

On Saturday, another cold front and area of low pressure will
shift southward into the Upper Midwest following the quick
eastward passage of a surface high across the Great Lakes
tonight. This front will be moving across our area into early
Sunday morning. However, prior to its arrival, a quick return to
breezy and unseasonably mild southwesterly winds across our
area for Saturday. Accordingly, Saturday is by far looking to be
the best day of the weekend as temperatures top out in the 70s
under mainly sunny skies. Also, the offshore flow will also
curtail lake breeze development, thus resulting in the mild
conditions extending all the way to the lakeshore.

Conditions will remain mild Saturday night in advance of the
approaching cold front. However, conditions will quickly turn
chilly following the cold frontal passage early Sunday morning
as breezy north-northeasterly winds develop. This will
especially be the case for areas north of the Illinois and
Kankakee Rivers, where high temperatures for the day are
expected to occur in the morning, with temperatures quickly
falling into the lower 40s near the lake, and into the mid 40s
and 50s across interior parts of northern IL. These colder
temperatures are also likely to be accompanied by gusty winds up
to 30 mph, a lower level deck of stratus and possibly a period
or two of light rain.

Broader WNW flow across the northern CONUS will take hold
across much of next week, with a continued series of waves
crossing somewhere across the Great Lakes region. Cooler but
seasonable conditions will persist Monday as high pressure
passes across the area. However, a compact wave removed from the
stronger WNW flow aloft is progged to pass just southwest of
the area on Tuesday and may brush the area with some cloud cover
and maybe even a few widely scattered showers. Otherwise, dry
conditions and warming temperatures are anticipated into the
midweek period ahead of the next approaching cold front. This
cold front looks to move across our area sometime around
Thursday of next week, with a period of cooler weather to follow
for the end of the week.

KJB

&&

.AVIATION /00Z TAFS THROUGH 06Z SUNDAY/...
Issued at 637 PM CDT Fri Mar 20 2026

Key aviation messages for the 00Z TAFs:

- Northeast winds becoming light east/variable overnight and
  southeast Saturday morning. Winds then become breezy southwest
  by early Saturday afternoon.

- Low (