HAMweather.com Area Forecast Discussion for County Warning Area MQT

Thu, 16 Feb 2012 11:28:47 GMT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MARQUETTE MI
611 AM EST THU FEB 16 2012

.SHORT TERM...(TODAY AND TONIGHT) 
ISSUED AT 603 AM EST THU FEB 16 2012

UPPER AIR PATTERN CONSISTS OF A 500 MB RIDGE OFF THE WEST COAST...A 
TROUGH IN THE WESTERN U.S. WITH A CLOSED LOW IN SOUTHERN CA...A 
TROUGH IN THE NORTHERN PLAINS WITH A SHORTWAVE ACROSS MISSOURI AND A 
BROAD RIDGE IN THE SOUTHEAST. 

THE TROUGH IN THE NORTHERN PLAINS MOVES EAST AND AFFECTS THE AREA 
TODAY. NAM BRINGS IN SOME 850-500 MB Q-VECTOR CONVERGENCE OVERNIGHT 
INTO THU MORNING BEFORE IT MOVES OUT BY THIS AFTERNOON. DEEPER 
MOISTURE MOVES THROUGH THE AREA AS WELL. GFS SHOWS ABOUT THE SAME 
THING AS WELL. LIGHT SNOW WILL CONTINUE TO PASS ACROSS THE AREA AS 
THE Q-VECTOR CONVERGENCE MOVES THROUGH ALONG WITH DEEPER MOISTURE. 
THE SNOW WILL SLOWLY MOVE OUT TODAY AS THE DEEPER MOISTURE DEPARTS 
ALONG WITH THE LIFT. NAM AND GFS SHOW 850 MB TEMPERATURES FALLING 
SLIGHTLY TO -8C TO -10C BY 00Z TONIGHT AND WITH LAKE TEMPERATURES OF 
2C TO 3C...THIS WOULD BE BORDERLINE FOR LAKE EFFECT PCPN. SINCE IT 
IS BORDERLINE WITH WEST WINDS...SNOW AMOUNTS WILL NOT BE VERY MUCH 
FOR TONIGHT. 

OVERALL FOR THE TODAY AND TONIGHT FORECAST...DID NOT MAKE MANY 
CHANGES TO THE GOING TEMPERATURES OR WEATHER OR POPS EXCEPT FOR SOME 
MINOR ADJUSTMENTS HERE AND THERE.

.LONG TERM...(FRIDAY THROUGH WEDNESDAY) 
ISSUED AT 603 AM EST THU FEB 16 2012

850MB TEMPS WILL CONTINUE TO DECREASE ON FRI...LOWERING TO NEAR -13C 
BY 00Z SAT...BUT SUBSIDENCE IN THE WAKE OF TODAY/S SHORTWAVE ALONG 
WITH DAYTIME HEATING/MIXING WILL DISRUPT ORGANIZATION OF LES BANDS 
LEADING TO SCT COVERAGE AT BEST AND LIGHT ACCUMS. CHANCE POPS STILL 
LOOK GOOD FOR FRIDAY IN THE NW TO WNW SNOWBELTS...WITH LESS THAN AN 
INCH OF SNOWFALL EXPECTED. MODELS INDICATE A VORT MAX AND ASSOC UPR 
JET WILL DIVE THROUGH THE NRN PLAINS ON FRIDAY HELPING PROPEL A SFC 
LOW JUST SOUTH OF THE REGION FRI AFTERNOON AND EVENING. 
HOWEVER...BASED ON THE WAA PATTERN AND ASSOC JET DYNAMICS WITH THIS 
FEATURE WOULD EXPECT BETTER FORCING FOR ANY SYNOPTIC SNOW TO 
GENERALLY STAY SOUTH OF THE CWA. THE SCNTRL CWA COULD MAYBE BE 
BRUSHED WITH A DUSTING OF LIGHT SNOW FM THIS SYSTEM SO WILL MAINTAIN 
SLIGHT CHC POPS ALONG THE WI BDR AND LAKE MI ZONES. 

MEDIUM RANGE MODELS ARE NOW IN GOOD AGREEMENT ON STRENGTH AND TIMING 
OF CLIPPER SHORTWAVE TROUGH MOVING THROUGH THE AREA FRI NIGHT AND 
SAT MORNING WHICH COULD AID IN ENHANCEMENT OF LES OFF LAKE SUPERIOR 
FRI NIGHT INTO EARLY SATURDAY. COLD ADVECTION (850 MB TEMPS LOWER TO 
-14C TO -16C BY 12Z SAT) COMBINED WITH ENHANCEMENT POTENTIAL FROM 
SHORTWAVE SHOULD PROVIDE A BOOST TO LES IN THE NNW TO NW WIND 
SNOWBELTS. WILL MAINTAIN LIKELY POPS DOWNWIND OF LAKE SUPERIOR IN 
THE NW TO NNW WIND SNOWBELTS FRI NIGHT INTO SAT 
MORNING...DIMINISHING LATE SAT AS SFC HIGH PRESSURE BUILDS IN FROM 
THE WEST AND 850 MB TEMPS BEGIN TO WARM. GIVEN QUICK PASSAGE OF 
SHORTWAVE AND LIMITED WINDOW FOR ENHANCEMENT EXPECT ANY LES ACCUMS 
TO STAY WELL BLO ADVISORY CRITERIA WITH TOTAL ACCUMS OF 1 TO LOCALLY 
3 INCHES.  

MODELS CONTINUE TO SHOW AMPLIFIED MID-UPR LVL RIDGE BUILDING OVER 
THE AREA SUNDAY INTO MONDAY WITH ABV NORMAL TEMPS EXPECTED AT LEAST 
INTO MIDWEEK. MODELS STILL IN GENERAL AGREEMENT ON SHORTWAVE MOVING 
THROUGH THE AREA...BRINGING THE POTENTIAL FOR SOME LIGHT SNOW AGAIN 
LATE MON NIGHT INTO TUE.

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 610 AM EST THU FEB 16 2012

LIGHT SNOW WILL CONTINUE TO MOVE OUT SHORTLY AT SAW. IMPROVING 
CONDITIONS WILL BE SLOW TO COME TO CMX AS WIND OFF THE LAKE WILL 
KEEP LOW LEVEL MOISTURE IN THROUGH THE PERIOD AND ALLOW THE MVFR 
CIGS TO STAY. AT IWD AND SAW...CONDITIONS WILL STAY VFR THROUGH THE 
PERIOD AS WEST WINDS WILL KEEP ANY LAKE EFFECT SNOW NORTH OF THOSE 
TWO SITES. COLD AIR ARRIVES TONIGHT AND LAKE EFFECT SNOW SHOWERS 
WILL KICK IN AT CMX.

.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 603 AM EST THU FEB 16 2012

WEST WINDS ARE EXPECTED TO INCREASE INTO THE 20 TO 30 KT RANGE 
TONIGHT IN THE WAKE OF A TROUGH MOVING THROUGH THE REGION. 
OTHERWISE...CONDITIONS WILL REMAIN RELATIVELY TRANQUIL INTO MONDAY 
WITH NO GALES EXPECTED.

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.