145
FXUS63 KLOT 072029
AFDLOT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE, IL
229 PM CST SAT FEB 7 2026
KEY MESSAGES
- QUICK SHOT OF SNOW POSSIBLE LATE TONIGHT OVER FAR NE IL AND
NW IN.
- MILDER TEMPERATURES EXPECTED FOR MUCH OF THE UPCOMING WORK
WEEK.
DISCUSSION
ISSUED AT 229 PM CST SAT FEB 7 2026
MID-LEVEL CLOUD COVER WILL CONTINUE TO INCREASE ACROSS THE AREA
INTO THIS EVENING IN ASSOCIATION WITH OUR NEXT QUICKLY
APPROACHING LOW AMPLITUDE SHORTWAVE IMPULSE RIDING THE NORTHWEST
FLOW INTO THE REGION TONIGHT. WHILE MUCH OF THE AREA WILL SEE
CLOUD COVER AROUND TONIGHT, WE DO CONTINUE TO MONITOR THE
POTENTIAL FOR A QUICK HIT OF LIGHT ACCUMULATING SNOW LATE
TONIGHT ACROSS A SMALL PORTION OF THE AREA. IT IS IMPORTANT TO
NOTE THAT MOST AREAS WILL NOT SEE ANY SNOW AS A RESULT OF THIS
IMPULSE TONIGHT, OWING TO THE VERY DRY LOW-LEVEL AIRMASS IN
PLACE. INSTEAD, WE ARE WATCHING AREAS GENERALLY ALONG A NARROW
NORTH-NORTHWEST TO SOUTH- SOUTHEAST ORIENTED CORRIDOR THAT
EXTENDS FROM SOUTHEASTERN WI AND FAR NORTHEASTERN IL (ESPECIALLY
IN CLOSE PROXIMITY TO LAKE MICHIGAN) SOUTHEASTWARD INTO PARTS
OF NORTHWESTERN IN. FORECAST GUIDANCE CONTINUES TO INSIST THAT
TOP-DOWN SATURATION WILL OCCUR IN THIS CORRIDOR AND SUPPORT A
SHORT PERIOD (2-4 HOURS) OF SNOW LATER TONIGHT. THIS CERTAINLY
SEEMS PLAUSIBLE SINCE THIS IS ALSO THE GENERAL REGION IN WHICH A
TRANSIENT BAND OF FRONTOGENESIS IS FAVORED TO DEVELOP AND
SUPPORT SOME ENHANCED FORCED ASCENT. WE HAVE THUS CONTINUED TO
CONFINE CHANCE TO LOW END LIKELY POPS (30-60% CHANCE) IN THIS
GENERAL AREA OVERNIGHT. THE SHORT DURATION OF SNOW SHOULD RESULT
IN LIGHT AMOUNTS OF A COATING TO PERHAPS LOCALLY UP TO AN INCH.
A LARGE SCALE WEATHER PATTERN CHANGE IS SLATED TO TAKE PLACE
INTO THE FIRST PORTION OF THE UPCOMING WORK WEEK. THIS WILL
OCCUR AS THE PERSISTENT HIGH AMPLITUDE RIDGING OVER WESTERN
NORTH AMERICA BEGINS TO DEAMPLIFY AND TRANSITION THE UPPER-LEVEL
PATTERN ACROSS MOST OF THE COUNTRY INTO A MORE QUASI-ZONAL FLOW
PATTERN (WEST-TO-EAST) FOR A PERIOD NEXT WEEK. OVERALL, THIS
WILL SET THE STAGE FOR A MILDER AIRMASS ACROSS OUR REGION THIS
WEEK AS THE VERY COLD AIRMASS REMAINS NORTH OF THE AREA.
THE THREAT OF PRECIPITATION ALSO LOOKS TO REMAIN LOW (<20%)
ACROSS OUR AREA THROUGH AT LEAST MID-WEEK, OWING TO EXPECTATION
OF WEATHER SYSTEMS TRACKING WELL NORTH AND SOUTH OF OUR AREA.
OUR MILDEST PERIOD THIS WEEK LOOKS TO BE MONDAY INTO TUESDAY,
WHEN HIGH TEMPERATURES LOOK TO TAG 40 DEGREES IN MOST AREAS. A
WEAK COLD FRONT IS EXPECTED TO DROP SOUTHWARD ACROSS THE AREA ON
TUESDAY. THIS SHOULD BRING COOLER (HIGHS IN THE 30S) MORE
SEASONABLE WEATHER BACK INTO THE REGION FOR THE REMAINDER OF THE
WEEK.
THERE REMAINS A LOT OF UNCERTAINTY WITH A POTENTIAL LATE WEEK
SYSTEM. DIDN'T MAKE ANY CHANGES TO THE POPS OFFERED UP BY THE
NBM, BUT THERE CONTINUES TO BE SOME SIGNAL FOR PRECIPITATION
POTENTIAL LATE IN THE WEEK, PARTICULARLY FROM EPS MEMBERS.
KJB
AVIATION /18Z TAFS THROUGH 00Z MONDAY/
ISSUED AT 1121 AM CST SAT FEB 7 2026
KEY MESSAGES FOR THE 18Z TAF PERIOD:
* A CHANCE FOR VFR SNOW SHOWERS AND FLURRIES TONIGHT AT
CHICAGOLAND SITES
NEAR-NORTHERLY WINDS AT UNDER 10 KT ARE VEERING TO NE HEADING
INTO THE AFTERNOON. THEY'LL CONTINUE TO VEER TO A ESE BY THIS
EVENING AND REMAIN AS SUCH THROUGH THE END OF THE PERIOD. EXPECT
10 TO 12 KT WITH GUSTS AS HIGH AS 20 KT FOR SUNDAY LATE MORNING
AND AFTERNOON.
A PUSH OF LIGHT SNOW SHOWERS WILL CLIP EXTREME NE IL AND INTO
NW IN TONIGHT. WHILE THE MORE IMPACTFUL COVERAGE IS FAVORED EAST
OF THE TERMINALS AND OUT OVER THE LAKE, SOME VFR SNOW SHOWERS
OR FLURRIES MAY FIND THEIR WAY OVER THE CHICAGOLAND SITES. IN
THE TAFS, MAINTAINED A PROB30 FOR THIS POTENTIAL OWING TO THE
POSSIBILITY THAT COVERAGE STAYS OUT OF REACH. TIME WINDOW FOR
THIS POTENTIAL IS ROUGHLY 05Z THROUGH 09Z.
DOOM
LOT WATCHES/WARNINGS/ADVISORIES
IL...NONE.
IN...NONE.
LM...NONE.
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