359
FXUS63 KLOT 091938
AFDLOT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE, IL
138 PM CST MON FEB 9 2026
KEY MESSAGES
- MILDER TEMPERATURES ARE EXPECTED FOR MUCH OF THE WEEK.
DISCUSSION
ISSUED AT 138 PM CST MON FEB 9 2026
A LOW-AMPLITUDE MID-LEVEL WAVE NEAR YELLOWSTONE WILL QUICKLY
TRACK EASTWARD THROUGH TONIGHT, CROSSING NORTHERN WISCONSIN LATE
TONIGHT. AHEAD OF THE WAVE LATE THIS AFTERNOON AND EVENING,
SUBSTANTIAL LOWER TROPOSPHERIC WAA/ISENTROPIC ASCENT WILL
ENCOUNTER A RATHER DRY AIRMASS, WITH THE ONLY NOTABLE EFFECTS ON
SENSIBLE WEATHER LIMITED TO PLENTY OF MID/UPPER-LEVEL CLOUDS,
STEADY OR GRADUALLY WARMING OVERNIGHT TEMPS, AND PERHAPS
SPORADIC GUSTS THROUGH THE NIGHT. THE ASSOCIATED COLD FRONT WILL
CROSS THE AREA IN THE PRE-DAWN HOURS THROUGH AROUND SUNRISE,
WITH GUSTY WINDS IN STORE FOR MUCH OF THE DAY ON TUESDAY. WITH A
SHARPENING LOW-LEVEL PRESSURE GRADIENT FROM A SECONDARY WAVE
CROSSING THE NORTHERN GREAT LAKES AND A MODESTLY FAVORABLE
ISALLOBARIC WIND COMPONENT, NW WINDS MAY SPORADICALLY GUST TO 30
TO 35 MPH DURING THE AFTERNOON.
A BROAD AND WEAKENING RIDGE OVER THE NORTHERN GREAT PLAINS ON
WEDNESDAY WILL SHIFT ACROSS THE WESTERN GREAT LAKES ON THURSDAY
BEFORE ANOTHER QUICK-MOVING WAVE TRAVERSES THE AREA LATE
THURSDAY INTO THURSDAY NIGHT. PERSISTENT LOW TO MID-LEVEL
ISENTROPIC ASCENT BELOW A SOMEWHAT STATIONARY RIGHT ENTRANCE
REGION OF THE UPPER-LEVEL JET WILL ALLOW FOR GRADUAL TOP-DOWN
SATURATION WEST OF THE AREA THROUGHOUT THE DAY THURSDAY. IT
REMAINS TO BE SEEN THOUGH IF THERE WILL BE ENOUGH SATURATION TO
THE SURFACE THIS FAR EAST BY THURSDAY EVENING AS SUPPORT FROM
THE UPPER-JET WILL BEGIN SHIFTING EAST OF THE AREA. WILL
MAINTAIN OVERALL LOW-END CHANCE POPS FOR LOW QPF AS SNOW ACROSS
MOST OF THE AREA THURSDAY AFTERNOON AND EVENING. ANY PRECIP
SHOULD END BY DAYBREAK FRIDAY WITH WEAK RIDGING SHIFTING ACROSS
THE AREA THROUGH THE DAY.
FOCUS THEN TURNS TO A SLOW-MOVING SUB-TROPICAL TROUGH OVER THE
BAJA OF CALIFORNIA LATE THIS WEEK AND ITS INTERACTION WITH, OR
LACK THEREOF, A FASTER CLUSTER OF DISTURBANCES TRACKING FROM THE
PACIFIC NORTHWEST AND BRITISH COLUMBIA TOWARD THE FAR NORTHERN
GREAT LAKES LATE SATURDAY INTO SUNDAY. ENSEMBLE AND ESPECIALLY
DETERMINISTIC GUIDANCE CONTINUES TO STRUGGLE WITH THE AMOUNT OF
THE NORTHWARD EXTENT OF PRECIP WITH THE STRONGER SOUTHERN WAVE,
PRIMARILY OWING TO THE HOW MUCH ENERGY WILL BE DRAWN INTO THE
NORTHERN WAVE. WHILE THERE HAS BEEN A SOUTHWARD TREND IN THE
PRECIP SHIELD OVER THE PAST SEVERAL ENSEMBLE CYCLES, WE ARE
STILL FIVE DAYS OR MORE OUT AND WILL NEED TO CONTINUE TO MONITOR
FUTURE TRENDS IN THE TRACK OF BOTH WAVES OVER THE COMING DAYS.
IN THE EVENT PRECIP DOES EXPAND WELL NORTH INTO THE AREA,
ACCUMULATING SNOW WILL BE IN PLAY LATE SATURDAY INTO EARLY
SUNDAY.
KLUBER
AVIATION /18Z TAFS THROUGH 00Z WEDNESDAY/
ISSUED AT 1109 AM CST MON FEB 9 2026
A VIGOROUS CLIPPER SYSTEM WILL RACE THROUGH THE GREAT LAKES
DURING THE TAF PERIOD. WITH A LACK OF LOW-LEVEL MOISTURE, THE
PRIMARY IMPACT OF THE SYSTEM WILL BE EXPRESSED VIA WINDS.
TO START, SURFACE WINDS WILL PREVAIL OUT OF THE SOUTH TO
SOUTHWEST DIRECTION (180 TO 200 DEG) THROUGH THE AFTERNOON
HOURS. TOWARD SUNSET, WIND DIRECTIONS MAY RESPOND TO SURFACE
DECOUPLING BY TURNING TOWARD THE SOUTHEAST (160 TO 180 DEG),
BEFORE TURNING BACK SOUTHWESTERLY BY MIDNIGHT. A STOUT
SOUTHWESTERLY LOW-LEVEL JET (45-50KT AT 2KFT) WILL DEVELOP
OVERHEAD THROUGH THE OVERNIGHT HOURS, LEADING TO LLWS. AFTER
DAYBREAK, A COLD FRONT WILL MOVE ACROSS THE AIRSPACE CAUSING
SURFACE WINDS TO TURN NORTHWEST (310 DEG OR SO). EFFICIENT
MIXING SHOULD SUPPORT PREVAILING GUSTS IN THE 25-30 KT RANGE
WITH OCCASIONAL GUSTS UP TO 35 KT.
BORCHARDT
LOT WATCHES/WARNINGS/ADVISORIES
IL...NONE.
IN...NONE.
LM...NONE.
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