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000
FXUS63 KMKX 061714 AAA
AFDMKX

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
1114 AM CST FRI DEC 6 2013

.UPDATE...

QUIET WEATHER IS EXPECTED TODAY...AND THE ONGOING TODAY PERIOD
GENERALLY LOOKS ON TRACK. MAIN CONCERN IS SKY COVER IN THE WAY OF
TRENDS AND CAPTURING THE CIRRUS INTO THIS AFTERNOON.

SATELLITE SHOWS CIRRUS FILTERING IN FROM THE SOUTH...THE MAJORITY
OF IT MOVING ACROSS SOUTHEAST WISCONSIN. SFC OBS MAP SHOWS A FEW
REPORTS OF ISO/SCT LOW LEVEL CLOUDS UNDERNEATH THE CIRRUS TO
CONTEND WITH AS WELL...BUT THEY SHOULDNT BE TOO MUCH OF A
CONCERN. LOW LEVELS ARE DRY.

AS SUCH...THE SOUTHEAST IS ANTICIPATED TO STAY UNDER THE CIRRUS
LONGER...THROUGH MID AFTERNOON AT LEAST. THE NORTHEAST HALF OF
THE FORECAST AREA SHOULD STAY MOSTLY SUNNY...AS IT IS CURRENTLY.
OTHERWISE...REST OF THE FORECAST APPEARS ON TRACK.

&&

.AVIATION/18Z TAFS/...

VFR CONDITIONS ARE EXPECTED THIS AFTERNOON...TONIGHT AND SATURDAY
ACROSS TAF SITES. WEST NORTHWEST WINDS WILL REMAIN GUSTY AT TIMES
THIS AFTERNOON AND TONIGHT...MAINLY AT THE EASTERN SITES. MIDDLE
TO HIGH CLOUDS OVER THE EASTERN SITES WILL GRADUALLY MOVE TO THE
EAST BY EARLY THIS EVENING. HIGH PRESSURE MOVING EASTWARD INTO THE
REGION TONIGHT AND SATURDAY WILL BRING CLEAR SKIES AND GRADUALLY
WEAKENING WINDS.

&&

.MARINE...

A RELATIVELY TIGHT PRESSURE GRADIENT OVER THE AREA THIS AFTERNOON
AND TONIGHT WILL BRING WEST NORTHWEST WINDS OF 15 TO 20 KNOTS. A
FEW GUSTS TO 25 KNOTS ARE EXPECTED...MAINLY NORTH OF PORT
WASHINGTON. HOWEVER...MOST OF THE GUSTS SHOULD BE BELOW 22
KNOTS...SO WILL NOT ISSUE A SMALL CRAFT ADVISORY FOR THIS PERIOD.
HIGH WAVES WILL REMAIN OVER THE OPEN WATERS OF LAKE MICHIGAN.

&&

.PREV DISCUSSION... /ISSUED 347 AM CST FRI DEC 6 2013/

SHORT TERM...

TODAY AND TONIGHT...FORECAST CONFIDENCE HIGH.

THE MAIN 250 MB TROUGH OVER THE WESTERN U.S. WITH A 170 KNOT JET
MAX MOVES ACROSS WISCONSIN TODAY...REACHING THE EASTERN GREAT
LAKES THIS AFTERNOON AS THE TROUGH AXIS BEGINS TO FLATTEN AND
LIFTS NORTHEAST. MOST OF THE UPPER DIVERGENCE AND 700 MB UPWARD
MOTION STAYS SOUTH OF THE FORECAST AREA TODAY AND TONIGHT.

700 MB LAYERS ARE VERY DRY...WITH SOME INCREASE IN RH ALONG THE
ILLINOIS BORDER TODAY AND EARLY THIS EVENING...WITH DRYING AS THE
UPPER JET MAX LIFTS NORTHEAST.  850 MB RH IS ALSO DRY.  THEREFORE
THE CLOUDS WILL BE JET RELATED AND BE THICKER TO THE SOUTHEAST.

MAIN CONCERN WILL BE THE COLD TEMPERATURES WITH JUST ENOUGH WIND TO
MAKE WIND CHILLS COME IN TO PLAY.  WIND CHILLS SHOULD BE IN THE
SINGLE DIGITS TODAY AND AROUND 10 BELOW TONIGHT...WITH SOME 15
BELOW READINGS OVER SOUTH CENTRAL AND NORTHERN PARTS OF
SOUTHEAST WISCONSIN.

SATURDAY THROUGH SATURDAY NIGHT...FORECAST CONFIDENCE HIGH

A BROAD UPPER TROUGH WILL KEEP THE COLD AIR STATIONED OVER THE UPPER
MIDWEST. THE SURFACE HIGH WILL MOVE OVERHEAD ON SATURDAY SO WEST TO
NORTHWEST WINDS WILL FINALLY DIMINISH. AS THE HIGH SLIDES EAST
SATURDAY NIGHT...THE MID TO UPPER LEVEL CLOUDS WILL INCREASE AS WARM
ADVECTION BEGINS AHEAD OF AN APPROACHING LONGWAVE TROUGH. HIGH TEMPS
WILL BE IN THE TEENS ONCE AGAIN SATURDAY. THEN THEY WILL FALL
QUICKLY SAT NIGHT BUT LEVEL OFF AS THE CLOUDS MOVE IN...SO LOWS
SHOULD BOTTOM OUT IN THE UPPER SINGLE DIGITS RATHER THAN COLDER.

SUNDAY...FORECAST CONFIDENCE MEDIUM TO HIGH.

LIGHT SNOW WILL SPREAD INTO SOUTHERN WI FROM THE WEST ON SUNDAY AS
AN UPPER LEVEL TROUGH MOVES INTO THE GREAT LAKES REGION. THE SYSTEM
WILL BE SATURATING FROM THE TOP DOWN...SO A LITTLE UNCERTAIN ABOUT
HOW QUICKLY THE SNOW WILL BEGIN TO REACH THE GROUND. THE BEST CHANCE
FOR SNOW WILL BE AFTER 18Z INLAND.

NEAR THE LAKE...ONGOING SOUTHEAST TO EASTERLY 1000-850MB FLOW WILL
LEAD TO LOW LEVELS SATURATING EARLIER. HOWEVER THERE IS DEBATE ABOUT
WHERE THE SNOW WILL BEGIN FIRST...NEAR KENOSHA/MILWAUKEE OR
SHEBOYGAN. EXPECTING LAKE ENHANCEMENT TO PLAY A ROLE IN SNOW TOTALS.

HIGHEST SNOWFALL RATES EXPECTED SUNDAY EVENING AS THE LOW UNDERGOES
CYCLOGENESIS OVER LOWER MICHIGAN AND SOUTHERN WI LANDS ROUGHLY ON
THE SOUTHERN EDGE OF THE DEFORMATION ZONE WITH 850-700MB
FRONTOGENESIS AND UPWARD MOTION IN THE VICINITY.

BUFKIT MODEL SOUNDINGS AND TIME-HEIGHT SERIES SHOW A DEEP DENDRITE
GROWTH ZONE /DGZ/...NEARLY 200MB OR 8000FT. OMEGA VALUES ARE NOT TOO
IMPRESSIVE...MAX AROUND -6 AT THE TOP OF THE DGZ. WENT WITH
CONSENSUS OF MODELS FOR QPF BUT ADDED A LITTLE NEAR THE LAKE... AND
A BLEND OF THE NAM AND GFS FOR SNOWFALL RATIOS WHICH IS AROUND 18 TO
19:1. STORM TOTAL SNOWFALL AMOUNTS SEEM TO BE AROUND 3 TO 4 INCHES
INLAND WITH AROUND 5 NEAR SHEBOYGAN. THE 06Z NAM CAME IN WITH HIGHER
QPF/SNOW AMOUNTS THAN THE PREVIOUS 00Z NAM AND GFS RUNS AND WILL
HAVE TO WAIT TO SEE IF THIS IS AN OUTLIER OR A NEW TREND. WILL
CONTINUE TO MENTION 3 TO 6 INCHES WITH HIGHEST AMOUNTS NEAR
SHEBOYGAN.

LONG TERM...

MONDAY THROUGH THURSDAY...FORECAST CONFIDENCE MEDIUM

DRY AIR WILL QUICKLY MOVE IN BEHIND THE SYSTEM SO EXPECT PRECIP TO
TAPER OFF QUICKLY AFTER MIDNIGHT SUN NIGHT. CUT POPS OUT ALMOST
COMPLETELY AFTER 12Z MON. ARCTIC AIR WILL FUNNEL IN ON BRISK
NORTHWEST WINDS AND WE WILL GET INTO THE COLDEST TEMPS OF THE SEASON
SO FAR.

AT THIS TIME...WED SEEMS LIKE IT WILL BE THE COLDEST BUT THAT HAS
BEEN WAVERING OVER THE PAST SEVERAL MODEL RUNS.

AVIATION/12Z TAFS/...

FEW CLOUDS AROUND 2 THSD FT MAINLY IN THE WISCONSIN RIVER VALLEY
AREA.  OTHERWISE VFR THROUGH THE PERIOD WITH MAINLY JET RELATED
CIRRUS TODAY AND THIS EVENING.


MARINE...

SMALL CRAFT ADVISORY CONDITIONS EXPECTED TO SUBSIDE BY SUNRISE
AND WILL LET THE SMALL CRAFT ADVISORY EXPIRE.

&&

.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&

$$

UPDATE...ET/WOOD
TODAY/TONIGHT AND AVIATION/MARINE...HENTZ
SATURDAY THROUGH THURSDAY...MRC