021  
FXUS63 KDTX 062359  
AFDDTX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI  
659 PM EST TUE JAN 6 2026  
   
KEY MESSAGES
 
 
- A CONTINUED WARMING TREND BRINGS HIGH TEMPS INTO THE 40S THROUGH  
MID-WEEK WITH 50S POSSIBLE THURSDAY AND FRIDAY.  
 
- THE NEXT ROUND OF WIDESPREAD RAIN IS EXPECTED LATE THURSDAY INTO  
THURSDAY NIGHT.  
 
- DYNAMIC LOW PRESSURE SYSTEM IS FORECASTED TO LIFT THROUGH THE  
REGION THIS WEEKEND. UNCERTAINTY EXISTS IN HEAVIEST PRECIPITATION  
AXIS.  
 

 
   
AVIATION
 
 
IFR TO LIFR CONDITIONS REMAIN ENTRENCHED ACROSS THE TERMINALS THIS  
EVENING AS A SURFACE LOW CROSSES SOUTHERN LOWER MICHIGAN. PERSISTENT  
LOW-LEVEL SATURATION WITH WEAK ASCENT HAS ENSURED A MIX OF FOG AND  
RAIN/DRIZZLE THROUGH THE EVENING HOURS. A FEW WET SNOWFLAKES COULD  
STILL MIX IN NORTH OF PTK. CONDITIONS WILL ONLY IMPROVE SLIGHTLY  
OVERNIGHT, STILL HOLDING IFR FOR MOST SITES INTO WEDNESDAY MORNING.  
WINDS REORIENT WESTERLY BEHIND THE DEPARTING LOW WHICH HELPS USHER  
IN SLIGHTLY LESS HUMID AIR, THEREFORE VISIBILITIES ARE EXPECTED TO  
IMPROVE PRIOR TO CEILINGS. DID DELAY THE HIGHER VISIBILITIES UNTIL  
LATER ON WEDNESDAY GIVEN UPSTREAM TRENDS AT/BELOW MVFR OVER WESTERN  
LOWER, WISCONSIN, AND ILLINOIS. CEILINGS HOLD IN THE LOW MVFR RANGE  
THROUGH MOST OF THE DAYLIGHT HOURS BEFORE LIFTING ABOVE 2 KFT AGL  
AND EVENTUALLY SCATTERING OUT WEDNESDAY EVENING AS FLOW BACKS  
SOUTHWESTERLY.  
 
FOR DTW...PREDOMINANTLY IFR WITH A BRIEF CATEGORY CHANGE BETTER OR  
WORSE THROUGH THE NEXT COUPLE OF HOURS, THEN LIFTING TO MVFR FOR  
MOST OF WEDNESDAY. PRECIPITATION IS GENERALLY OVER, BUT LIGHT  
DRIZZLE (LIQUID) REMAINS POSSIBLE.  
 
DTW THRESHOLD PROBABILITIES...  
 
* HIGH FOR CEILING AT OR BELOW 5000 FEET THROUGH WEDNESDAY.  
 
* LOW FOR CEILINGS AND/OR VISIBILITIES AT OR BELOW 200 FEET AND/OR  
1/2 SM THE REST OF THE EVENING.  
 
* HIGH IN LIGHT PRECIPITATION TYPE AS LIQUID.  
 

 
   
PREV DISCUSSION
 
 
ISSUED AT 323 PM EST TUE JAN 6 2026  
 
DISCUSSION...  
 
COLD GROUND, SATURATED LOWER TROPOSPHERE, AND DEWPOINTS IN THE  
MIDDLE 30S HAS RESULTED IN WIDESPREAD DENSE FOG ACROSS MOST OF THE  
SOUTHERN FORECAST AREA. GIVEN THE BREADTH OF THE OBSERVATIONS AND  
THE LOW-MID LOW CIRCULATION IS NOT SET TO REACH THE EASTERN CWA  
BORDER TO AROUND 00Z, PREFERENCE WAS TO HAVE A DENSE FOG ADVISORY, I  
69 CORRIDOR SOUTHWARD, THROUGH THE EVENING COMMUTE. NWP SUPPORTS  
THAT DEEPER FRONTOGENESIS RESPONSIBLE FOR WIDESPREAD PRECIPITATION  
WILL WANE RAPIDLY AFTER 00Z AS THE CENTER OF MIDLEVEL LOW PRESSURE  
CIRCULATION PASSES OVERHEAD OF THE I 69 CORRIDOR. THERE WILL BE SOME  
TRAILING ABSOLUTE VORTICITY MAXIMA MERIDIONALLY FROM LAKE SUPERIOR  
VICINITY DOWN TO ILLINOIS THAT WILL NEED TO ADVECT THROUGH THE STATE  
THIS EVENING. DIFFERENTIAL CYCLONIC VORTICITY ADVECTION AND A  
PERSISTENCE OF SOME CONVERGENCE IS SHOWN TO RESULT IN SOME LAST  
VESTIGES OF DEEPER/MIDLEVEL DEFORMATION LATE TONIGHT. A LOW POP  
EXISTS LATE TONIGHT FOR SOME POTENTIAL OF DRIZZLE/FREEZING DRIZZLE  
OR SNOW SHOWER. NO IMPACTS ANTICIPATED FROM PRECIPITATION.  
 
BROAD SPLIT STREAM RIDGING WILL BUILD OVER THE CENTRAL GREAT LAKES  
WEDNESDAY THROUGH THE FIRST HALF OF THURSDAY. FORECAST SOUNDINGS  
SHOW ACTIVE SUBSIDENCE OCCURRING AROUND 9.0 KFT AGL EARLY IN THE  
DAY, WITH THE BASE OF THE SUBSIDENCE LOWERING TO POSSIBLY 2.5 KFT  
AGL BY EARLY EVENING. THE AGGRESSIVE DRYING OFFERS AN OPTIMISM OF  
CLEARING, BUT GUIDANCE SUGGESTS IT WILL BE VERY LATE (AFTER 20Z).  
HIGHS IN THE UPPER 30S.  
 
STRONG POTENTIAL VORTICITY ANOMALY OFF OF THE BAJA CALIFORNIA WITH  
ARRIVAL OF DEEP TROUGHING IN PACIFIC NORTHWEST WEDNESDAY AND  
THURSDAY WILL RESULT IN DOWNSTREAM RIDGE AMPLIFICATION AND THE  
DEVELOPMENT OF DEEP SOUTHWESTERLY RETURN FLOW ACROSS SOUTHEAST  
MICHIGAN. CURRENT INDICATIONS ARE THAT FAR SOUTHERN STREAM PV  
ANOMALY WILL BE KICKED NORTHEASTWARD WITH TOO MUCH SEPARATION AND  
LITTLE MERGING THROUGH SOUTHEAST MICHIGAN. A VERY WARM SYSTEM, 850MB  
DEWPOINTS OF +8 OR +9C. FROM THIS VANTAGE POINT THERE APPEARS AT  
SOME POTENTIAL FOR NEUTRAL STABILITY TO INSTABILITY BETWEEN 4.0-20.0  
KFT AGL. CONVECTIVE RAINFALL POSSIBLE AND ELEVATED THUNDER MAY BE  
NEEDED IN THE FORECAST THURSDAY NIGHT. CURRENT 75TH PERCENTILE OF  
THE EPS IS ABOUT .40 TO .50 INCH. HIGHS BOTH THURSDAY AND FRIDAY MAY  
RANGE IN THE 40S TO 50S.  
 
AGEOSTROPHIC CIRCULATIONS DEVELOPING IN RESPONSE TO STRONG  
GEOPOTENTIAL HEIGHT FALLS AND CHANGES IN UPPER LEVEL JET STREAK  
CURVATURE IS FORECASTING A DYNAMIC STORM SYSTEM OVER THE REGION THIS  
WEEKEND. UNCERTAINTY EXISTS DUE TO TIMING CONCERNS IN BOTH VORTICITY  
MERGING AND UPPER LEVEL JET PHASING. CURRENT DATA SUGGESTS ANOTHER  
WARM SYSTEM HERE LOCALLY AND THAT IS WHERE THE FORECAST CURRENTLY  
RESIDES. DEPENDING ON THE EVENTUAL TRACK OF THE SURFACE LOW, STRONG  
WIND CONCERNS MAY ARISE. BULK OF WRAP AROUND SNOW CHANCES LOOKS TO  
BE SUNDAY.  
 
MARINE...  
 
LOW PRESSURE LIFTS TOWARD THE SOUTHERN LAKE HURON BASIN THIS  
AFTERNOON-EVENING. ONGOING PRECIPITATION COVERAGE HAS BEEN GREATEST  
NORTH OF THE SYSTEM'S WARM FRONT, WHICH WILL KEEP STEADY RAIN GOING  
INTO TONIGHT. THE MORE WIDESPREAD IMPACT OF THIS LOW HAS BEEN A  
BLANKET OF FOG ACROSS THE GREAT LAKES, WHICH MAY BECOME LOCALLY  
DENSE AT TIMES THIS EVENING. WINDS BECOME MORE UNIFORM BY WEDNESDAY  
MORNING AS THE LOW DEPARTS AND HIGH PRESSURE FILLS IN. THIS SUPPORTS  
A QUIETER MID WEEK PERIOD BEFORE THE NEXT STRING OF LOW PRESSURE  
SYSTEMS IMPACT THE GREAT LAKES FRIDAY INTO THIS WEEKEND. INITIALLY,  
WARM AND STABLE CONDITIONS WILL PREVENT AN OTHERWISE ENERGETIC LOW  
LEVEL JET FROM MIXING TO THE SURFACE TO KEEP WIND GUSTS AROUND 30  
KNOTS OR LESS.  
 

 
   
DTX WATCHES/WARNINGS/ADVISORIES
 
 
MI...DENSE FOG ADVISORY UNTIL 9 PM EST THIS EVENING FOR MIZ060>063-  
068>070-075-076-082-083.  
 
LAKE HURON...NONE.  
LAKE ST CLAIR...NONE.  
MICHIGAN WATERS OF LAKE ERIE...NONE.  

 
 

 
 
AVIATION.....KGK  
DISCUSSION...CB  
MARINE.......MV  
 
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE  
AT WWW.WEATHER.GOV/DETROIT.  
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.

The Nexlab MI Page Main Text Page