063  
FXUS63 KMKX 211837  
AFDMKX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI  
137 PM CDT WED OCT 21 2026  
   
KEY MESSAGES  
 
- FOG POSSIBLE TONIGHT & THURSDAY EVENING/NIGHT.  
 
- ABOVE NORMAL TEMPERATURES & RAIN-FREE CONDITIONS CONTINUE INTO  
THE WEEKEND.  
 
- TEMPERATURES TRENDING BACK TOWARD NORMAL NEXT WEEK, WITH  
CHANCES FOR RAIN MONDAY NIGHT INTO TUESDAY AND WEDNESDAY  
NIGHT.  
 
 
   
SHORT TERM  
 
ISSUED 140 PM CDT WED OCT 21 2026  
 
THIS AFTERNOON THROUGH SATURDAY NIGHT:  
 
SYNOPSIS/MESOANALYSIS: HIGH PRESSURE IS CENTERED ALONG THE NORTH  
DAKOTA-MANITOBA BORDER THIS AFTERNOON, WITH A COLD FRONT EXTENDING  
FROM QUEBEC TOWARD THE NORTHERN LAKE SUPERIOR VICINITY. POSITIONING  
OF THE FEATURES IS ALLOWING FOR LIGHT SOUTHWESTERLY BREEZES TO  
BECOME ESTABLISHED ACROSS SOUTHERN WISCONSIN. COMBINED WITH ABUNDANT  
SUNSHINE, THE BREEZES ARE ALLOWING TEMPERATURES TO CLIMB QUICKLY  
TOWARD THE 70 DEGREE MARK AS OF THE 1 PM CDT HOUR. ANTICIPATE THAT  
TEMPS WILL CONTINUE TO CLIMB INTO THE LOW-MID 70S BY MID-AFTERNOON  
UNDER PERSISTING MOSTLY SUNNY SKIES. MID-UPPER LEVEL RIDGING WILL  
BUILD INTO THE MISSOURI VALLEY TONIGHT, ALLOWING THE AFOREMENTIONED  
AREA OF HIGH PRESSURE TO BROADEN IN SIZE. EXPANSION OF THE HIGH WILL  
WIDDLE AWAY AT THE LEADING COLD FRONT, WITH ONLY A NON-BAROCLINIC,  
NORTHERLY WIND SHIFT LEFT BY DAYBREAK. THE WIND SHIFT WILL WORK  
THROUGH THE AREA THURSDAY AS HIGH PRESSURE MOVES DIRECTLY OVERHEAD.  
PROXIMITY OF THE HIGH & AFFILIATED LIGHT/VARIABLE WINDS WILL SUPPORT  
PERIODS OF FOG POTENTIAL BOTH TONIGHT & THURSDAY EVENING/NIGHT.  
SOUTHWEST WINDS WILL QUICKLY RETURN AS THE HIGH DEPARTS EAST ON  
FRIDAY, MAINTAINING ABOVE NORMAL HIGH TEMPERATURES INTO THE WEEKEND.  
 
TONIGHT: WILL BE MONITORING FOR AREAS OF FOG DEVELOPMENT AS HIGH  
PRESSURE BUILDS IN FROM THE NORTHERN PLAINS. EXTENT---AS WELL AS  
DENSITY---OF ANY FOG WILL BE HIGHLY SENSITIVE TO LOW LEVEL WIND  
SPEEDS, WHICH REMAIN UNCERTAIN GIVEN SOUTHERN WISCONSIN'S  
POSITIONING ON THE SOUTHEAST FLANK OF THE BUILDING HIGH & WITHIN THE  
AFFILIATED SURFACE PRESSURE GRADIENT. IF FULL DECOUPLING OF THE  
BOUNDARY LAYER CAN OCCUR, DEEPER MOISTURE RETURNS ARRIVING ON THE  
HEELS OF THIS AFTERNOON'S SOUTHWESTERLY WINDS COULD BE SUPPORTIVE OF  
SOME DENSE FOG. WILL BE MONITORING VISIBILITY TRENDS THROUGH THE  
OVERNIGHT HOURS & ISSUING ANY HEADLINES SHOULD CONDITIONS WARRANT.  
SLOW DOWN, USE LOW BEAM HEADLIGHTS, AND ALLOW FOR EXTRA FOLLOWING  
DISTANCE IF ENCOUNTERING FOG ON THE ROADS.  
 
THURSDAY EVENING & NIGHT: WILL BE WATCHING FOR ADDITIONAL, MORE  
ADVECTION-BASED FOG AS PASSING HIGH PRESSURE & AFFILIATED EAST-  
NORTHEAST FLOW DRAW A MARINE AIR MASS INLAND FROM LAKE MICHIGAN.  
SIMILAR TO TONIGHT, IT REMAINS TOO EARLY TO TELL IF ANY FOG COULD BE  
DENSE. WILL BE MONITORING TRENDS OVER COMING FORECAST UPDATES.  
 
QUIGLEY  
 
 
   
LONG TERM  
 
ISSUED 140 PM CDT WED OCT 21 2026  
 
SUNDAY THROUGH WEDNESDAY:  
 
SYNOPSIS: ABOVE NORMAL TEMPERATURES WILL CONTINUE TO PREVAIL DURING  
THE DAY SUNDAY AS A SLOW-MOVING COLD FRONT DRIFTS INTO NORTHERN  
WISCONSIN. WITH FRONTAL FORCING REMAINING WELL-REMOVED FROM THE  
REGION, DRY CONDITIONS ARE CURRENTLY EXPECTED ALONG WITH THE WARM  
TEMPERATURES. MOVING INTO NEXT WEEK, GLOBAL ENSEMBLE GUIDANCE IS IN  
GENERAL AGREEMENT FOR 1) AN UPPER SHORTWAVE PASSAGE DURING THE  
MONDAY-TUESDAY TIMEFRAME AND 2) THE ARRIVAL OF A LARGER-SCALE UPPER  
TROUGH AND SURFACE FRONTAL PUSH BY THE MIDDLE OF THE WEEK/CONCLUSION  
OF THE LONG TERM PERIOD. NORTHERLY SURFACE MASS RESPONSES AFFILIATED  
WITH THE EARLY WEEK SHORTWAVE WILL HELP SHOVE THE SUNDAY COLD FRONT  
THROUGH SOUTHERN WISCONSIN ON MONDAY, BRINGING MORE SEASONABLE  
TEMPERATURES TO THE AREA THROUGH THE FIRST HALF OF NEXT WEEK. RAIN  
CHANCES RETURN TO THE FORECAST DURING THE PASSAGE OF BOTH  
PERTURBATIONS, WITH MONDAY NIGHT INTO TUESDAY & WEDNESDAY NIGHT INTO  
THURSDAY CURRENTLY FAVORED FOR THE MOST WIDESPREAD ACTIVITY.  
THUNDERSTORM CHANCES APPEAR LOW AT THIS TIME.  
 
MONDAY THROUGH WEDNESDAY: HAVE LARGELY MAINTAINED AN NBM FORECAST  
THROUGH THIS PORTION OF THE PERIOD GIVEN ENSEMBLE AGREEMENT  
REGARDING SYNOPTIC PATTERN EVOLUTION. SAID FORECAST PULLS HIGH  
TEMPERATURES BACK INTO THE MID-50S TO LOW-60S, IN ADDITION TO  
BRINGING CHANCE (~25-40%) PRECIP PROBABILITIES TO THE REGION MONDAY  
NIGHT/TUESDAY AND WEDNESDAY NIGHT. BARRING CHANGES IN CONSISTENCY  
ACROSS THE GLOBAL ENSEMBLE SUITE, WOULD ANTICIPATE GENERAL STABILITY  
IN THIS FORECAST INTO THIS WEEKEND. WILL CONTINUE TO MONITOR FOR ANY  
POSSIBLE CHANGES OVER COMING UPDATES.  
 
QUIGLEY  
 
 
   
AVIATION  
 
ISSUED 140 PM CDT WED OCT 21 2026  
 
PREDOMINANTLY VFR FLIGHT CATEGORIES PREVAIL THROUGH THE PERIOD AT  
ALL TERMINALS. LIGHT SOUTHWEST WINDS WILL TREND CALM TO VARIABLE  
OVERNIGHT AS HIGH PRESSURE MOVES EAST INTO THE OHIO RIVER VALLEY.  
FOG IS POSSIBLE OVERNIGHT, WITH CONFIDENCE TOO LOW TO JUSTIFY ANY  
MENTIONS AT THIS TIME. WILL BE MONITORING VISIBILITY TRENDS INTO  
TONIGHT AND MAKE ADJUSTMENTS TO THE FORECAST WHERE NECESSARY. SKIES  
WILL REMAIN MAINLY CLEAR THROUGH THE MAJORITY OF THE PERIOD. LAKE  
EFFECT CLOUDS BASED NEAR OR BELOW FL050 MAY MATERIALIZE THURSDAY  
AFTERNOON, WITH MENTIONS ADDED NEAR THE END OF THE 30 HOUR FORECAST  
PERIOD AT MKE IN THE 18Z UPDATE. WILL EVALUATE POSSIBLE MENTIONS IN  
THE VICINITY OF SBM AHEAD OF THE UPCOMING 00Z FORECAST. NOT  
ANTICIPATING ANY PRECIPITATION IN LAKE EFFECT CLOUDS, THOUGH VIS  
REDUCTIONS CAN'T BE RULED OUT. SHOULD CONFIDENCE IN VIS REDUCTIONS  
INCREASE, MENTIONS WILL BE INSERTED IN LATER FORECASTS.  
 
QUIGLEY  
 
 
   
MARINE  
 
ISSUED 140 PM CDT WED OCT 21 2026  
 
A RIDGE OF 1026 MB HIGH PRESSURE IS CENTERED FROM THE MISSISSIPPI  
RIVER INTO ONTARIO THIS AFTERNOON, RESULTING IN LIGHT SOUTH TO  
SOUTHWEST WINDS ACROSS THE OPEN WATERS. WINDS WILL TREND OUT OF THE  
NORTHEAST TONIGHT THROUGH THURSDAY NIGHT AS THE SURFACE RIDGE NUDGES  
EAST TOWARD THE OHIO RIVER AND QUEBEC. AREAS OF FOG ARE POSSIBLE  
OVER THE NORTHERN TWO-THIRDS OF THE LAKE LATE TONIGHT INTO THURSDAY.  
WHETHER ANY FOG BECOMES DENSE REMAINS UNCERTAIN, WITH VISIBILITY AND  
SATELLITE TRENDS BEING CLOSELY MONITORED THROUGH THIS PART OF THE  
PERIOD. PERSISTENT SOUTHERLY WINDS WILL BECOME ESTABLISHED FRIDAY  
THROUGH THE WEEKEND AS A COLD FRONT MOVES THROUGH THE NORTHERN GREAT  
PLAINS AND 1033 MB HIGH PRESSURE SETTLES INTO THE NORTHEASTERN  
UNITED STATES. WINDS COULD BE BREEZY AT TIMES, THOUGH WIDESPREAD  
GALES ARE NOT ANTICIPATED AT THIS TIME. WILL CONTINUE TO MONITOR FOR  
POSSIBLE INCREASES THROUGH THE SECOND HALF OF THE WEEK.  
AFOREMENTIONED COLD FRONT WILL CROSS THE WATERS SUNDAY NIGHT,  
BRINGING A NORTHERLY WIND SHIFT THROUGH THE FIRST HALF OF NEXT WEEK.  
RAIN SHOWERS ARE POSSIBLE ALONG THE PASSING FRONT.  
 
AREAS OF FOG ARE POSSIBLE THURSDAY AND THURSDAY NIGHT IN NEARSHORE  
ZONES. WHETHER ANY FOG WILL BECOME DENSE REMAINS UNCERTAIN, WITH  
TRENDS BEING MONITORED INTO TOMORROW. PERIODS OF SMALL CRAFT  
ADVISORY WIND GUSTS AND WAVES ARE POSSIBLE SATURDAY AHEAD OF AN  
APPROACHING COLD FRONT, PARTICULARLY FROM MILWAUKEE AND POINTS  
NORTH. WILL BE MONITORING TRENDS FOR POSSIBLE HEADLINES THROUGH THE  
END OF THE WEEK. WINDS WILL TREND NORTHERLY BEHIND THE FRONT EARLY  
NEXT WEEK, WITH PERIODS OF SMALL CRAFT ADVISORY LEVEL WAVES POSSIBLE  
TUESDAY.  
 
QUIGLEY  
 
 
   
MKX WATCHES/WARNINGS/ADVISORIES  
 
WI...NONE.  
LM...NONE.  
 
 
 
 
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