685 
FXUS63 KDTX 160819
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
419 AM EDT TUE MAR 16 2010

.SHORT TERM...TODAY

DEEP DRY AIR MASS NOW ENCOMPASSING THE GREAT LAKES REGION AS WEAK 
UPPER RIDGING DRIFTS THROUGH TODAY.  THE RESULTANT PATTERN OF 
GENERAL SUBSIDENCE WILL ENSURE SKIES REMAIN MOSTLY SUNNY /OUTSIDE OF 
SOME PATCHY CIRRUS/ THROUGH THE DAY.  THE LOW LEVEL THERMAL PROFILE 
REMAINS SIMILAR TO YESTERDAY...WITH THE NOTED CHANGES BEING A MORE 
PROLONGED PERIOD OF FULL INSOLATION AND SLIGHTLY HIGHER MIXED LAYER 
HEIGHTS.  GIVEN THAT HIGHS FROM YESTERDAY MADE THE MID/UPPER 50S 
DESPITE THE LIMITED INSOLATION EARLY...THIS SETUP POINTS TOWARD 
STAYING ON THE WARMER SIDE OF GUIDANCE.  THIS WILL BRING HIGHS AGAIN 
INTO THE MID-UPPER 50S TODAY.  EXCEPTION WILL BE ACROSS AREAS NEAR 
THE LAKES...WITH A PERSISTENT /ALBEIT LIGHT/ NORTHEAST FLOW OFF THE 
COLDER WATERS.

&&

.LONG TERM...TONIGHT THROUGH NEXT MONDAY

A WEAK MIDLEVEL TROUGH WILL SLIDE SOUTHWARD THROUGH THE CWA DURING 
THE MORNING HOURS ON WEDNESDAY. SURFACE WINDS WILL EMERGE OUT OF THE 
WEST BEHIND THIS FEATURE. MODEL SOUNDINGS SHOW A SLIGHT INCREASE IN 
MOISTURE BETWEEN 600-400 MB BUT CONDITIONS WILL REMAIN 
SUBSATURATED/NOT EXPECTING ANY CLOUDS. MODELS DO SHOW MIXING HEIGHTS 
RISING ABOVE 900MB FOR THE AFTERNOON...BUT WOULD BE SHOCKED IF IT 
DID NOT MAKE IT TO 850MB. THEREFORE...WILL CONTINUE THE MAX 
TEMPERATURE FORECAST OF UPPER 50S TO NEAR 60.

GUIDANCE IS STRONGER WITH THE MIDLEVEL LOW/SURFACE REFLECTION THAT 
WILL SLIDE EASTWARD NORTH OF LAKE SUPERIOR. THIS WILL NOT HAVE ANY 
IMPACTS ON PRECIPITATION OR CLOUDS HERE IN SOUTHEASTERN 
MICHIGAN...BUT SHOULD KEEP THE SURFACE LAYER SOMEWHAT COUPLED 
WEDNESDAY NIGHT...RAISED LOW TEMPERATURES UPWARD A CATEGORY. THE 
LACK OF AN INVERSION AND A LITTLE STRONGER SOUTHWESTERLY GRADIENT 
FLOW ON THURSDAY WILL ALLOW TEMPERATURES TO CLIMB QUICKLY. UPPED THE 
HIGH TEMP FORECAST A FEW DEGREES FOR ALL AREAS WITH NEAR 60 VALUES 
ACROSS THE NORTH...LOWER 60S SOUTH (THESE MAY YET BE A TOUCH ON THE 
CONSERVATIVE SIDE). A HIGH CLOUD CANOPY WILL OVERSPREAD SOUTHEASTERN 
MICHIGAN DURING THEY DAYTIME ON FRIDAY. STILL SOME QUESTION ON 
OPTICAL THICKNESS OF THESE CLOUDS BUT SHOULD BE ENOUGH WITH SOME 
WEAK CAA TO KEEP TEMPERATURES IN THE LOWER TO MIDDLE 50S.

GFS ARRIVED THIS EVENING IN SUPPORT OF THE 12Z ECMWF...WHICH BRINGS 
THE NEXT WEATHER SYSTEM THROUGH SOUTHEASTERN MICHIGAN NEXT WEEKEND. 
THIS PARTICULAR SOLUTION KEEPS THE WARM SECTOR IN PLACE OVER 
SOUTHERN PORTIONS OF THE STATE AND DOES NOT ALLOW ANY CHANGEOVER TO 
SNOWFLAKES UNTIL SUNDAY. GOING FORECAST HAS THIS WELL IN HAND.

&&

.MARINE...

LARGE HIGH PRESSURE OVER THE NORTHERN PLAINS WILL SLOWLY DROP  
SOUTHEAST THROUGH THE MID WEEK PERIOD...WITH RIDGING EXTENDING 
INTO THE GREAT LAKES REGION IN THE PROCESS. THIS WILL MAINTAIN DRY 
AND STABLE CONDITIONS WITH LIGHT WINDS OVER THE MARINE WATERS 
THROUGH THIS TIME.  LIGHTER WINDS WILL PERSIST THROUGH THE END OF 
THE WEEK AS A WEAK COLD FRONT DROPS INTO THE REGION.

&&

.PREV DISCUSSION...ISSUED 108 AM EDT TUE MAR 16 2010 

AVIATION...

DRIER AIR WILL REMAIN IN PLACE THROUGHOUT THIS TAF PERIOD.  THIS 
WILL MAINTAIN CLEAR SKIES /OUTSIDE OF OCCASIONAL CIRRUS/.  BRIEF 
PATCHY MVFR BR REMAINS POSSIBLE FOR A COUPLE HOURS ON EITHER SIDE OF 
SUNRISE THIS MORNING.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MI WATERS OF LAKE ERIE...NONE.

&&

$$

SHORT TERM...MR
LONG TERM....CB
MARINE.......MR
AVIATION.....MR


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