035  
FXUS63 KDTX 231033  
AFDDTX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI  
633 AM EDT WED MAY 23 2018  
 
   
AVIATION
 
 
SATELLITE WOULD SUGGEST VARIABILITY IN THE DEPTH OF THE FOG LAYER  
ACROSS SE MI EARLY THIS MORNING. FROM PTK UP THROUGH FNT, THE FOG  
MAY PERSIST PAST 13Z GIVEN THE DEPTH INDICATED ON SATELLITE. AS FOR  
METRO DETROIT AND MBS, THE SHALLOW NATURE OF THE FOG AND RECENT VSBY  
TRENDS SUGGEST VISIBILITY IMPROVEMENT BY 12Z OR SHORTLY THEREAFTER.  
OTHERWISE, HIGH PRESSURE OVERHEAD WILL SUSTAIN CLEAR SKIES AND LIGHT  
WINDS THROUGH THE TAF PERIOD.  
   
DTW THRESHOLD PROBABILITIES
 
 
 
* NONE.  
 

 
   
PREV DISCUSSION
 
 
ISSUED AT 240 AM EDT WED MAY 23 2018  
 
DISCUSSION...  
 
MORNING FOG, ESPECIALLY NORTH OF I-69 WHERE DENSE FOG HAS DEVELOPED  
(ISSUED DENSE FOG ADVISORY DOWN TO THE M-59 CORRIDOR), WILL BURN OFF  
BY MID MORNING AS THE LATE MAY SUN GOES TO WORK. DRY AND WARM  
STRETCH OF WEATHER WILL COMMENCE TODAY AS UPPER LEVEL RIDGE AXIS  
ADVANCES INTO THE CENTRAL GREAT LAKES REGION, ARRIVING ON FRIDAY.  
LARGE DIURNAL TEMPERATURE SWINGS IN STORE, AND WITH LARGE SURFACE  
HIGH (1022+ MB) LINGERING TONIGHT, FOG REMAINS A POSSIBILITY, AS 00Z  
NAM CONDENSATION PRESSURE DEFICITS CRASH OVERNIGHT, ALTHOUGH NAM MAY  
BE A BIT TOO AGGRESSIVE AND WILL JUST INCLUDE PATCHY FOG FOR NOW.  
 
850 MB TEMPS OF 12 TO 13 C TODAY WILL SUPPORT HIGHS NEAR 80 DEGREES.  
LOW TO MID 80S ON THURSDAY AS LOW LEVEL SOUTHWEST WINDS BEGIN TO  
TAKE HOLD AND 850 MB TEMPS REACH AND SLIGHTLY EXCEED 14 C. GOOD WARM  
RETURN FLOW AROUND THE HIGH ON FRIDAY WILL SUPPORT HIGHS IN THE MID  
TO UPPER 80S AS 850 MB TEMPS REACH AND SLIGHTLY EXCEED 17 C. AIRMASS  
LOOKS TO REMAIN RELATIVELY STABLE RIGHT THROUGH FRIDAY. THE AIRMASS  
WILL THEN DESTABILIZE OVER THE WEEKEND AS HEIGHT FALLS TAKE PLACE AND  
GENERAL TROUGHING BECOMES ESTABLISHED OVER THE GREAT LAKES REGION,  
ALTHOUGH BULK OF UPPER LEVEL ENERGY/DISTURBANCES TO TRACK THROUGH THE  
NORTHERN GREAT LAKES. NONE-THE-LESS, SUFFICIENT INSTABILITY/MOISTURE  
LIKELY OVER SOUTHEAST MICHIGAN TO LEAD TO SOME SHOWER AND  
THUNDERSTORM ACTIVITY, BUT COVERAGE AND TIMING REMAINS PROBLEMATIC  
THIS FAR OUT. COLD FRONT STILL DRAPED ACROSS FAR SOUTHERN LOWER  
MICHIGAN ON MONDAY WILL MAINTAIN THE LOW CHANCE, BUT LARGE SURFACE  
HIGH LOOKS TO BUILD BACK IN MONDAY EVENING INTO TUESDAY, PER 00Z  
EURO, PROVIDING ANOTHER COUPLE DAYS OF DRY AND WARM WEATHER.  
 
MARINE...  
 
LIGHT WEST-NORTHWEST WINDS WILL OCCUR ACROSS THE LAKES THIS MORNING  
AHEAD OF HIGH PRESSURE NOW CENTERED OVER SOUTHERN LAKE MICHIGAN.  
WINDS WILL BECOME LIGHT AND VARIABLE DURING THE COURSE OF THE  
AFTERNOON AS THIS HIGH EXPANDS ACROSS LAKES HURON AND ERIE. THE HIGH  
WILL SUSTAIN LIGHT AND VARIABLE WINDS INTO THURSDAY. AS THE HIGH  
DRIFTS TO THE EAST COAST BY FRIDAY AND A SLOW MOVING FRONT  
APPROACHES FROM THE NORTHWEST, LIGHT SOUTH-SOUTHWEST WINDS WILL  
DEVELOP BY FRIDAY AND WILL PERSIST INTO THE WEEKEND.  
 

 
   
DTX WATCHES/WARNINGS/ADVISORIES
 
 
MI...DENSE FOG ADVISORY UNTIL 9 AM EDT THIS MORNING FOR MIZ047>049-  
053>055-060>063-068>070.  
 
LAKE HURON...NONE.  
LAKE ST CLAIR...NONE.  
MICHIGAN WATERS OF LAKE ERIE...NONE.  

 
 

 
 
AVIATION.....SC  
DISCUSSION...SF  
MARINE.......SC  
 
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE  
AT WWW.WEATHER.GOV/DETROIT.  
 
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