382  
FXUS63 KDTX 241052  
AFDDTX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI  
652 AM EDT FRI OCT 24 2014  
 
   
AVIATION
 
 
//DISCUSSION...  
 
PARTLY TO MOSTLY CLOUDY SKIES (VFR) AROUND TODAY AS BATCH OF  
MOISTURE SLOWLY WORKS THROUGH SOUTHEAST MICHIGAN. LATE DAY AND EARLY  
EVENING DRYING WILL TAKE PLACE...BUT LOW CHANCE OF MVFR DECK  
DEVELOPING TOWARD SUNSET. A RENEWED PUSH OF MOISTURE WILL OCCUR  
TONIGHT AHEAD OF A COLD FRONT...LIKELY SUPPPORTING LOW VFR/HIGH MVFR  
CEILINGS BY SATURDAY MORNING.  
 
//DTW THRESHOLD THREATS...  
 
* LOW CONFIDENCE ON CEILINGS BELOW 5000 FEET TODAY INTO  
TONIGHT...MEDIUM CONFIDENCE EARLY SATURDAY MORNING.  
 

 
   
PREV DISCUSSION
 
ISSUED 333 AM EDT FRI OCT 24 2014  
 
SHORT TERM... TODAY AND TONIGHT  
 
ONE BATCH OF ELGONATED SOUTH-NORTH MOISTURE (PW VALUES AROUND 0.75  
INCHES) IS MOVING THROUGH LOWER MICHIGAN EARLY THIS MORNING...AS A  
FORMIDABLE SHORTWAVE IS TRACKING THROUGH FAR SOUTHERN LAKE MICHIGAN  
AND INTO THE OHIO VALLEY. SHORTWAVE RIDGING WILL BUILD IN BEHIND  
THIS UPPER WAVE TODAY OVER SOUTHERN LOWER MICHIGAN. 925 MB TEMPS  
FORECASTED TO RISE TO 10 C...PER BOTH 00Z GFS AND NAM. THIS SUGGESTS  
TODAY WILL BE A BIT WARMER...LOWER 60S/AROUND 60...BUT THERE IS SOME  
HESITATION WITH AMOUNT OF LOW LEVEL MOISTURE/CLOUDS AROUND.  
 
NEXT SURGE OF MOISTURE WILL ARRIVE VERY LATE TONIGHT AHEAD OF  
APPROACHING COLD FRONT...AS THE UPPER LEVEL ENERGY RACES ACROSS FAR  
SOUTHERN CANADA TODAY. THERE IS LITTLE IF ANY HEIGHT FALLS OCCURRING  
OVER THE SOUTHERN GREAT LAKES THROUGH 12Z SATURDAY...AND WITH 1000-  
500 MB MEAN RH REMAINING LESS THAN 60 PERCENT...PLANNING ON  
MAINTAINING THE DRY FORECAST. WITH THE INCREASING SOUTHWEST GRADIENT  
AND CONTINUED MODEST LOW LEVEL WARM ADVECTION OVERNIGHT...PLANNING  
ON HOLDING MINS IN THE MID 40S.  
 
LONG TERM...SATURDAY THROUGH THURSDAY  
 
A STRUNG OUT DRY LOW PRESSURE SYSTEM...CURRENTLY SEEN ON WATER VAPOR  
IMAGERY OVER THE WESTERN US/CANADIAN BORDER...WILL CONTINUE TRACKING  
EAST DURING THE NEXT COUPLE OF DAYS...EVENTUALLY TRACKING THROUGH  
THE NORTHERN GREAT LAKES REGION ON SATURDAY. THIS SYSTEM WILL BRING  
A WEAK COLD FRONT THROUGH THE AREA AS IT PASSES TO THE NORTH AND NOT  
MUCH ELSE. DESPITE THE MODELS SPITTING OUT SOME QPF WITH THIS  
SYSTEM...MODEL SOUNDINGS ARE VERY DRY WITH LITTLE IN THE WAY OF LIFT  
AS THE MAIN SHORTWAVE WILL BE WELL TO THE NORTH. EXPECTATIONS WITH  
THIS SYSTEM ARE FAIRLY LOW...WITH CLOUDS AND SOME GUSTY WINDS BEING  
THE MAIN THREAT AS THE AFOREMENTIONED WEAK COLD FRONT PASSES THROUGH  
ON SATURDAY.  
 
RIDGING WILL BRING DRY...QUIET WEATHER TO THE CENTRAL GREAT LAKES ON  
SUNDAY WITH SLIGHTLY COOLER TEMPERATURES BEHIND THE WEAK COLD FRONT  
DESPITE ABUNDANT SUNSHINE. AN APPROACHING LOW WILL BRING INCREASING  
CLOUDS SUNDAY NIGHT AND MONDAY AS A WARM FRONT LIFTING NORTH BRINGS  
THE CHANCE FOR SHOWERS ACROSS THE SAGINAW VALLEY AND THUMB REGION ON  
MONDAY.  
 
A DEEPER MID LEVEL TROUGH AND ATTENDANT SHORTWAVE WILL BRING  
INCREASED CHANCES FOR RAIN MONDAY NIGHT AND TUESDAY AS INCREASED  
TOTAL TOTALS AND K-INDEX VALUES BRING THE THREAT FOR A FEW RUMBLES  
OF THUNDER DURING THIS PERIOD WITH INCREASED INSTABILITY. THE NWP  
MODELS HAVE COME INTO BETTER AGREEMENT REGARDING THE HIGHEST CHANCE  
OF RAIN ON TUESDAY WITH THIS SYSTEM...THEREFORE HAVE RAISED POPS  
DURING THIS PERIOD TO REFLECT THE GREATER DEGREE OF CONFIDENCE.  
 
TEMPERATURES COOL DOWN SEVERAL DEGREES BEHIND THE FRONT WEDNESDAY  
AND THURSDAY...AS RIDGING KEEPS THE WEATHER QUIET DURING THE MIDDLE  
TO LATER PART OF THE WORK WEEK.  
 
MARINE...  
 
A TRANQUIL WIND REGIME WILL GIVE WAY TO DEVELOPING MODERATE  
SOUTHWEST FLOW ON SATURDAY IN ADVANCE OF AN APPROACHING SYSTEM. THE  
ASSOCIATED COLD FRONT WILL TRAVERSE AREA WATERS SATURDAY AFTERNOON  
INTO SUNDAY EVENING. WINDS WILL QUICKLY TURN NORTHWEST AND BECOME  
FRESH TO STRONG...ESPECIALLY OVER THE OPEN WATERS OF CENTRAL LAKE  
HURON...WITH GUSTS TO NEAR 30 KNOTS LIKELY OVER THE NORTHERN HALF OF  
LAKE HURON ON SATURDAY NIGHT. A GUSTY MODERATE TO FRESH NORTHWEST  
BREEZE WILL THEN PERSIST ACROSS THE WATERS THROUGH SUNDAY.  
 

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

 
 

 
 
AVIATION.....SF  
SHORT TERM...SF  
LONG TERM....KURIMSKI  
MARINE.......KURIMSKI  
 
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE  
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).  
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.

The Nexlab MI Page Main Text Page