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000
FXUS63 KAPX 021445
AFDAPX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
945 AM EST MON DEC 2 2013

.SYNOPSIS...
ISSUED AT 300 AM EST MON DEC 2 2013

WEAK HIGH PRESSURE OVER THE WESTERN GREAT LAKES REGION WILL KEEP OUR
WEATHER DRY BUT CLOUDY TODAY. PRECIPITATION CHANCES WILL INCREASE
TUESDAY AS A WARM FRONT LIFTS THROUGH MICHIGAN...WITH A MIX OF RAIN
AND SNOW EVENTUALLY CHANGING OVER TO ALL RAIN ON WEDNESDAY.
PRECIPITATION WILL CHANGE BACK OVER TO ALL SNOW WEDNESDAY NIGHT AS A
COLD FRONT BLASTS THROUGH THE REGION.

&&

.UPDATE...
ISSUED AT 944 AM EST MON DEC 2 2013

BROAD HIGH PRESSURE IN PLACE ACROSS THE GREAT LAKES THIS MORNING.
GENERALLY QUIET...BUT THERE IS A SUBTLE SHORT WAVE TROUGH MOVING
THROUGH THE REGION THAT HAS BROUGHT ABOUT A SUBTLE BUMP UP IN
INVERSION HEIGHTS AND WEAK UPWARD FORCING. ENOUGH TO PRODUCE A
HYBRID BROAD AREA OF LAKE INDUCED/SYNOPTIC LIGHT PRECIP ACROSS
PARTS OF THE CWA. MAINLY FLURRIES AS INVERSION HEIGHTS ARE JUST UP
INTO THE -12C/-13C RANGE...ALTHOUGH THERE MIGHT BE SOME
INTERMINGLED -FZDZ AS WELL.

HAVE EXTENDED FLURRIES/LIGHT FREEZING DRIZZLE OUT THROUGH THE REST
OF THE MORNING. RUC13 DATA THEN SUGGESTS FORCING WILL FALL APART
BY EARLY AFTERNOON AND WE SHOULD SEE A DOWNWARD TREND TO THE
LIGHT/NUISANCE PRECIP. WILL SEE.


UPDATE ISSUED AT 619 AM EST MON DEC 2 2013

PATCHY FREEZING DRIZZLE HAS EXPANDED ACROSS THE STRAITS AND FAR
NRN LWR MICHIGAN EARLY THIS MORNING PER LATEST KAPX 88D BASE REF
LOOP. SURFACE OBS HAVE YET TO REPORT THIS PHENOMENA...BUT A COUPLE
OF EARLY MORNING SPOTTER REPORTS CONFIRM THAT SOME VERY LIGHT
PRECIP IS REACHING THE GROUND. HAVE SPREAD PATCHY FREEZING DRIZZLE
INTO THESE AREAS AND HAVE EXTENDED THE OCCURRENCE THRU 15Z AS
SHALLOW LOW LEVEL MOISTURE REMAINS TRAPPED BELOW THE SUBSIDENCE
INVERSION AND SOME VERY WEAK SHEAR CONTINUES AT THE TOP OF THE
MOIST LAYER. REST OF THE DAY WILL BE CLOUDY WITH TEMPS ONLY
WARMING INTO THE LOW TO MID 30S.

&&

.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 300 AM EST MON DEC 2 2013

KINDA "DIRTY" HIGH PRESSURE EXTENDING ACROSS THE NORTHWOODS AT THIS
EARLY HOUR...WITH PLENTY OF CLOUDS STUCK BELOW STRONG H8 SUBSIDENCE
INVERSION (PER LOCAL 00Z SOUNDING). STILL SOME WEAK LAKE PROCESSES
ONGOING IN MARGINALLY COLD ENOUGH ATMOSPHERE...WITH EVEN A WELL
EVIDENT LAKE-INDUCED MESO LOW SPINNING HARMLESSLY ACROSS NORTHERN
LAKE MICHIGAN. ENOUGH LIFT/LAKE MOISTURE CONTRIBUTION TO KICK OFF A FEW
FLURRIES FOR SOME...BUT THAT`S ABOUT IT. MID AND UPPER LEVEL PATTERN
JUST ABOUT AS NONDESCRIPT AS THE SURFACE FEATURES...WITH GENERALLY
LIGHT WEST TO NORTHWEST FLOW ALOFT...WITH MUCH STRONGER JET ENERGY
WELL TO OUR WEST (LEADING CORE OF 100+ KNOT UPPER JET PUNCHING INTO
THE NORTHERN ROCKIES). JUST NOT A WHOLE LOT OF CHANGE EXPECTED
THROUGH THIS EVENING...WITH WAA PROCESSES RAMPING UP TOWARD TUESDAY
MORNING WELL AHEAD OF ORGANIZING CENTRAL PLAINS LOW PRESSURE.
THUS...FORECAST CONCERNS REMAIN RATHER TRIVIAL...CENTERING ON
CLOUD/TEMPERATURE TRENDS AS WELL AS SOME WEAK LAKE PROCESSES THROUGH
THIS EVENING. POSSIBLE LATE NIGHT WAA PRECIP WILL ALSO NEED
ADDRESSING.

BASICALLY...WHAT YOU SEE IS WHAT YOU GET TODAY. HAVING A HARD TIME
BELIEVING RATHER AGGRESSIVE DRYING BELOW INVERSION LEVEL NOTED IN
MODEL DERIVED SOUNDINGS. NAM-BUFR INITIATION FAR TOO DRY ALREADY AT
INVERSION LEVEL...AND GIVEN VERY LIGHT WIND FIELDS TODAY (SIMPLY NO
MECHANICAL MIXING)...FEEL CURRENT CLOUD DECK WILL BE AWFULLY HARD
TO "BURN" OFF. WILL CONTINUE TO TREND MORE PESSIMISTICALLY WITH
CLOUD COVER...JUST FEATURING A FEW AFTERNOON BREAKS...BUT STILL
CALLING IT MOSTLY CLOUDY. ONLY PRECIP CONCERNS APPEARS TIED TO
NORTHWEST PUSH OF CURRENT NORTHERN LAKE MICHIGAN MESO-LOW. WILL
INTRODUCE FLURRY WORDING INTO MACKINAC COUNTY THIS MORNING AS THIS
FEATURE MOVES ASHORE. OTHERWISE...DESPITE THE CLOUDY DAY...DRY
CONDITIONS LOOK TO PREVAIL. NOT A WHOLE LOT OF DIURNAL TEMPERATURE
RESPONSE...WITH AFTERNOON READINGS RUNNING IN THE LOWER AND MIDDLE
30S.

STATUS-QUO THROUGH THIS EVENING...WITH PERHAPS A FEW MORE BREAKS
IN THE OVERCAST BEFORE HIGH LEVEL CLOUDS SPREAD ACROSS THE REGION IN
DEVELOPING TOP-DOWN SATURATION REGIME. GUIDANCE TRYING TO SATURATE
THE COLUMN RIGHT TOWARDS SUNRISE DOWN NEAR MANISTEE AS ISENTROPIC
UPGLIDE INCREASES AHEAD OF DEVELOPING CENTRAL PLAINS STORM SYSTEM.
MAIN SHOW SHOULD REMAIN OFF TO OUR WEST...BUT CANNOT COMPLETELY RULE
OUT SOME LIGHT SNOWS BY SUNRISE ACROSS THE FAR SOUTHWEST.

.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 300 AM EST MON DEC 2 2013

TUESDAY AND WEDNESDAY...WEATHER BECOMES MORE ACTIVE TUESDAY AHEAD OF
A WARM FRONT LIFTING INTO THE WRN GREAT LAKES REGION. THIS FRONT IS
ASSOCIATED WITH DEEPENING LOW PRESSURE IN THE NRN PLAINS. EASTERLY
LOW LEVEL WINDS WILL GRADUALLY SHIFT SE ON TUESDAY AS THE WARM FRONT
NEARS...AND THEN TO THE SOUTH ON WEDNESDAY ONCE THE WARM FRONT LIFTS
NORTH OF OUR CWA. WARMER AIR WILL STEADILY SURGE NORTHWARD THRU OUR
CWA BEGINNING TUESDAY MORNING AND CONTINUING THRU MUCH OF WEDNESDAY.
850 MB TEMPS WILL WARM FROM ROUGHLY -4 C ACROSS NRN LWR MICHIGAN AT
12Z TUESDAY TO 6 C BY 12Z WEDNESDAY. PERSISTENT LOW CLOUDS WILL
LIMIT THE AFFECTS OF WAA AT THE SURFACE. AS THE LOW LEVEL TEMP
PROFILE CHANGES...SO WILL PRECIP TYPE AS MOISTURE AND THUS POPS
GRADUALLY INCREASE FROM SW TO NE ACROSS OUR CWA ON TUESDAY. WILL
NEED TO WATCH MODEL SOUNDINGS CLOSELY FOR THE POSSIBILITY OF SOME
SLEET OR FREEZING RAIN TUESDAY AND TUESDAY NIGHT AS WARMER AIR ALOFT
GRADUALLY WORKS ITS WAY NORTHWARD BEFORE THE BOUNDARY LAYER HAS A
CHANCE TO FULLY REALIZE THE WAA. FOR NOW...WILL KEEP PRECIP TYPE
SIMPLE GIVEN ALL OF THE UNKNOWNS THIS FAR OUT. PRECIP TYPE SHOULD
INITIALLY BE ALL SNOW...CHANGING TO A MIX OF RAIN AND SNOW...AND
EVENTUALLY ALL RAIN AS WAA WORKS ITS WAY NORTHWARD THRU OUR CWA
TUESDAY AND TUESDAY NIGHT. BY WEDNESDAY...PRECIP TYPE SHOULD BE ALL
RAIN ACROSS OUR ENTIRE CWA. LATEST NAM CONTINUES TO BE MORE
AGGRESSIVE WITH COLD FROPA...NOW BRINGING THE COLD AIR BACK INTO THE
REGION WEDNESDAY NIGHT. EXPECT RAIN WILL MIX WITH AND CHANGE BACK
OVER TO SNOW FROM NW TO SE DURING THE EVENING...WITH ALL SNOW
EXPECTED BY LATE WEDNESDAY NIGHT AS 850 MB TEMPS COOL BACK TO -4 C
BY 12Z THURSDAY. GIVEN THIS SCENARIO...HIGH TEMPS MAINLY IN THE 30S
ON TUESDAY WILL WARM INTO THE UPPER 30S AND LOWER 40S FOR WEDNESDAY
WHEN WAA WILL PEAK. OVERNIGHT LOWS TUESDAY NIGHT WILL ONLY COOL A
FEW DEGREES...DROPPING BACK INTO THE UPPER 20S TO MID 30S. TEMPS
WILL FALL BACK INTO THE 20S WEDNESDAY NIGHT AS CAA COMMENCES.

THURSDAY THRU SUNDAY...CAA CONTINUES THURSDAY AND FRIDAY AS 850 MB
TEMPS FURTHER COOL TO -20 C BY 00Z SATURDAY. LATEST ECMWF SHOWS
WESTERLY LOW LEVEL FLOW SETTING UP THURSDAY IN THE WAKE OF THE COLD
FRONT...WITH VERY LITTLE CHANGE IN THIS TRAJECTORY THRU SATURDAY
NIGHT. THIS COULD SET THE STAGE FOR A PROLONGED WESTERLY FLOW LAKE
EFFECT SNOW EVENT FOR THE LAST PART OF THE WEEK. THIS POTENTIAL
EVENT IS STILL SEVERAL DAYS OUT WITH TOO MANY UNKNOWNS TO GET TOO
SPECIFIC OR DETAILED AT THIS TIME. WILL CERTAINLY KEEP A CLOSE EYE
ON SUBSEQUENT MODEL RUNS TO SEE HOW THIS SCENARIO EVOLVES. FOR
NOW...WILL HIGHLIGHT HIGHEST POPS ACROSS OUR WESTERLY FLOW AREAS OF
ERN UPR AND NW/N CENTRAL LWR MICHIGAN. SUNDAY LOOKS LIKE A
TRANSITION DAY AS LOW LEVEL FLOW SHIFTS TO THE SOUTH AHEAD OF OUR
NEXT LOW PRESSURE SYSTEM. INCREASING SYNOPTIC LIFT AND MOISTURE ON
SUNDAY SHOULD BRING MORE WIDESPREAD SNOWS TO ALL OF NORTHERN
MICHIGAN. WITH PROGRESSIVE CAA TAKING PLACE THRU THIS TIME...
AFTERNOON HIGHS WILL COOL FROM THE LOWER 30S ON THURSDAY TO THE
UPPER TEENS TO MID 20S FOR SATURDAY. LOW TEMPS WILL BE MAINLY IN THE
TEENS FOR THE LAST PART OF THE WEEK AND THE WEEKEND.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 619 AM EST MON DEC 2 2013

LOW VFR CIGS WILL HOLD OVER ALL OF NRN LWR MICHIGAN THRU TUESDAY
MORNING AS SHALLOW LOW LEVEL MOISTURE REMAINS TRAPPED BELOW THE
SUBSIDENCE INVERSION. SOME PATCHY FREEZING DRIZZLE WILL IMPACT THE
REGION THIS MORNING...WILL LEAVE OUT OF THE TAF FOR NOW GIVEN THE
PATCHY NATURE OF THIS VERY LIGHT PRECIP. WINDS WILL REMAIN LIGHT
THRU THE FORECAST PERIOD.


&&

.MARINE...
ISSUED AT 300 AM EST MON DEC 2 2013

LIGHT WINDS CONTINUE THROUGH THIS EVENING AS WEAK SURFACE
RIDGE CUTS THROUGH THE AREA. EAST TO SOUTHEAST WINDS BEGIN TO PICK
UP TONIGHT WELL AHEAD OF LOW PRESSURE ORGANIZING OVER THE CENTRAL
PLAINS. STRONGER SOUTHEAST WINDS ARRIVE TUESDAY AND TUESDAY
NIGHT...WITH SOME SCA/S POSSIBLE DURING THIS PERIOD.


&&

.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.

&&

$$

UPDATE...BA
SYNOPSIS...MR
SHORT TERM...MB
LONG TERM...MR
AVIATION...MR
MARINE...MB