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000
FXUS63 KMKX 040258 AAA
AFDMKX

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
858 PM CST TUE DEC 3 2013

.UPDATE...
WILL KEEP DENSE FOG ADVISORY GOING IN SPITE OF SOME OBSERVATIONS
POPPING UP TO 1 TO 2 MILES WITH THE LIGHT RAIN BANDS. THE LAST LIGHT
RAIN BAND SHOULD PUSH NE OF SHEBOYGAN AND FOND DU LAC COUNTIES
AROUND 12 MIDNIGHT WITH VSBYS FALLING BACK TO 1/4 MILE OR LESS
THROUGH THE OVERNIGHT INTO WEDNESDAY MORNING.

LATEST HRRR AND 00Z/04 NAM 12 VISIBILITY FORECASTS INDICATING
IMPROVING VISIBILITIES BEFORE 15Z...AND POSSIBLY BEFORE 12Z IN
THE FAR SE...AS WINDS TURN SOUTHEAST AND INCREASE AS WARM FRONT
ATTEMPTS TO LIFT INTO/THROUGH SRN WI AHEAD OF DEEPENING SURFACE
LOW. WILL LET LATER SHIFT HAVE FULL LOOK AT ALL NEW DATA AND
TRENDS TO SEE IF END TIME OF ADVISORY NEEDS TO BE ADJUSTED.

SOME CONCERN IN THE FAR NW FOR SOME FREEZING FOG AS NE WINDS
PULLING SOME FREEZING TEMPS INTO LOCATIONS NW OF A FOND DU
LAC...PORTAGE TO LONE ROCK LINE. TEMPS EXPECTED TO RISE OVERNIGHT
AS LOW APPROACHES SO WILL NOT ANTICIPATE A HEADLINE THERE BUT WILL
MAKE MENTION OF SLIPPERY SPOTS IN NPW UPDATE.

&&

.AVIATION/06Z TAFS/...
LITTLE IMPROVEMENT IN IFR/LIFR CONDITIONS UNTIL DEEPENING SURFACE
LOW LIFTS PAST TO THE NE AND PUSHES DRIER...COLDER AIR BEHIND
TRAILING COLD FRONT THROUGH SRN WI WEDNESDAY EVENING. MODELS STILL
SHOWING A BAND OF PRECIPITATION ALONG FRONT...WHICH WOULD BE ALL
RAIN AHEAD OF THE FRONT...CHANGING TO SNOW JUST BEHIND THE FRONT
BEFORE ENDING. DO NOT EXPECT ACCUMULATIONS WITH THE BRIEF PERIOD
OF LIGHT SNOW.

&&

.MARINE...

WILL KEEP DENSE FOG ADVISORY GOING AS INCREASINGLY WARM AND MOIST
AIR STREAMS OVER LAKE AS SURFACE LOW APPROACHES EASILY HOLDING
VSBYS AT OR BELOW 1 MILE. SHOULD SEE IMPROVEMENT LATE
MORNING/EARLY AFTERNOON. NO CHANGE TO SMALL CRAFT HEADLINES WITH
ONSHORE NE FLOW CONTINUING OVER NRN ZONES KEEPING WAVES UP WHILE
LIGHTER WINDS IN THE SOUTHERN ZONES NEAR WARM FRONT WILL HOLD
WAVES WELL BELOW CRITERIA. EXPECT ANOTHER ADVISORY TO BE ISSUED
FOR TOMORROW NIGHT AS GUSTY WEST WINDS EXCEED CRITERIA THROUGH
MOST OF THURSDAY AFTERNOON.

&&

.PREV DISCUSSION... /ISSUED 322 PM CST TUE DEC 3 2013/

TONIGHT AND WEDNESDAY...FORECAST CONFIDENCE MEDIUM.

WITH SURFACE LOW PRESSURE APPROACHING FROM THE PLAINS...SOUTHERN
WISCONSIN WILL REMAIN NORTH OF THE SURFACE AND 850MB WARM FRONT
THROUGH MOST OF TONIGHT. THEN AS THE BROAD LOW MOVES INTO IL AND
SOUTHERN WI WED MORNING...THE WARM FRONT WILL GRADUALLY LIFT INTO
CENTRAL WI. HOWEVER...THE WEAK PRESSURE GRADIENT WILL ALLOW FOG AND
LOW CLOUDS TO HANG AROUND LONGER.

EXPANDED THE DENSE FOG ADVISORY UP THROUGH ALL OF THE MKX FORECAST
AREA...IN EFFECT UNTIL NOON TOMORROW. ALSO ISSUED A MARINE DENSE FOG
ADVY THROUGH MID WED AFTERNOON. TEMPS AND DEWPOINTS WILL BE ON THE
RISE WED MORNING AS WE GET INTO THE WARM SECTOR WHICH WILL ENHANCE
THE FOG.

AS FOR PRECIP...THANKFULLY IT WILL BE ALL RAIN WITH ABOVE FREEZING
TEMPS TONIGHT THROUGH WED AFTERNOON. LOOK FOR PERIODS OF LIGHT RAIN
AND THEN PERIODS OF DRIZZLE OR NOTHING. BEST CHANCE FOR CONTINUOUS
LIGHT RAIN WILL BE TOWARD CENTRAL WI. FORCING IS LIGHT...BUT THERE
IS 850/700MB WARM AIR ADVECTION...700MB UPWARD MOTION...500MB
VORTICITY ADVECTION WITH NUMEROUS WEAK SHORTWAVES AND VERY WEAK
UPPER DIVERGENCE IN THE EXIT REGION OF AN UPPER JET. THE UPWARD
MOTION AND MOISTURE CONVERGENCE DECREASES LATE TONIGHT AS THE LOW
LEVEL WIND MAX LIFTS NORTHEAST SO EXPECT DIMINISHING PRECIP AND
THEREFORE DENSE FOG ESPECIALLY WED MORNING.

WEDNESDAY NIGHT...FORECAST CONFIDENCE IS MEDIUM.

THE COLD FRONT WILL EXIT SOUTHEAST WISCONSIN DURING THE EVENING
WITH STRONG COLD AIR ADVECTION IN ITS WAKE. WE COULD SEE SOME
LINGERING LIGHT PRECIPITATION IN THE EVENING...ANY RAIN OR
RAIN/SNOW WILL CHANGE OVER TO LIGHT SNOW BRIEFLY...BEFORE ENDING.
LITTLE OR NO ACCUMULATION IS EXPECTED. LOWS WILL DROP QUICKLY INTO
THE 20S.

THURSDAY THROUGH SATURDAY...FORECAST CONFIDENCE IS HIGH.

ARCTIC HIGH PRESSURE BUILDS IN AND TEMPERATURES WILL TURN VERY
COLD. HIGHS ON THURSDAY SHOULD STILL MANAGE TO HIT THE MID TO
UPPER 20S...BUT FRIDAY AND SATURDAY WILL ONLY SEE HIGHS IN THE
TEENS. THAT WILL BE PUSHING 15 TO 20 DEGREES BELOW NORMAL. LOWS BY
SATURDAY MORNING WILL BE IN THE SINGLE DIGITS. THE HIGH WILL KEEP
IT DRY ACROSS THE AREA.

SUNDAY AND MONDAY...FORECAST CONFIDENCE IS MEDIUM.

THE GFS/GEM/ECMWF ARE SHOWING A MID LEVEL SHORT WAVE TRACKING FROM
THE SOUTHERN ROCKIES AND INTO THE WESTERN GREAT LAKES SUNDAY
THROUGH SUNDAY NIGHT. THE ECMWF IS STRONGEST WITH THE CYCLOGENESIS
OVER OUR AREA LATE SUNDAY INTO SUNDAY NIGHT. AT THIS POINT...IT/S
NOT A VERY STRONG SYSTEM...BUT IT LOOKS LIKE IT COULD HAVE A
COUPLE TENTHS OF LIQUID WITH IT THAT WOULD TRANSLATE INTO ABOUT 2
TO 3 INCHES OF SNOW GIVEN THE HIGH LIQ/SNOW RATIOS WITHIN THE
PRE-EXISTING COLD AIRMASS OVER THE AREA. THE SNOW SHOULD BE
EXITING THE AREA QUICKLY BY MONDAY WITH COLD HIGH PRESSURE COMING
BACK IN FOR TUESDAY.

AVIATION/00Z TAFS/...

SOUTHERN WI WILL REMAIN ON THE NORTH SIDE OF THE WARM FRONT
THROUGH MUCH OF THE NIGHT AND THEN GET INTO A WEAK PRESSURE
GRADIENT THROUGH WEDNESDAY MORNING. THEREFORE...EXPECT DENSE FOG
WITH 1/4 TO 3/4SM VSBY AND CEILINGS BELOW 500 FEET TO PERSIST
THROUGH WEDNESDAY MORNING. THERE COULD BE BRIEF PERIODS OF
IMPROVEMENT DURING ANY LIGHT RAIN SHOWERS...BUT TOO MUCH UNCERTAINTY
TO TIME THAT CORRECTLY IN THE TAFS.

EXPECTING FURTHER IMPROVEMENT WED AFTERNOON AS THE COLD FRONT
APPROACHES. SOUTH WINDS WILL BECOME WEST AND GUSTY WITH THE COLD
FRONTAL PASSAGE BETWEEN 7 AND 10 PM WED EVENING. SNOW COULD MIX WITH
RAIN ALONG THE FRONT...BUT EXPECT PRECIP TO END SHORTLY AFTER THE
FRONT GETS THROUGH.


MARINE...

A SMALL CRAFT ADVISORY IS IN EFFECT AS BRISK SOUTHEAST WINDS
CONTINUE NORTH OF THE NORTH POINT LIGHTHOUSE. EXPECT WAVES TO
SUBSIDE AS WINDS BECOME DUE SOUTH WED AFTERNOON...BUT ESPECIALLY WED
NIGHT AS THEY BECOME WESTERLY BEHIND A STRONG COLD FRONT. BRISK AND
GUSTY WEST NORTHWEST FLOW WILL THEN PREVAIL THE REMAINDER OF THE
WEEK. A SMALL CRAFT ADVISORY WILL BE NEEDED BEHIND THE FRONT.

&&

.MKX WATCHES/WARNINGS/ADVISORIES...
WI...DENSE FOG ADVISORY UNTIL NOON CST WEDNESDAY FOR WIZ046-047-051-
     052-056>060-062>072.

LM...DENSE FOG ADVISORY UNTIL 3 PM CST WEDNESDAY FOR LMZ643>646.

     SMALL CRAFT ADVISORY UNTIL NOON CST WEDNESDAY FOR LMZ643-644.

&&

$$

UPDATE...REM
TONIGHT/WEDNESDAY AND AVIATION/MARINE...MRC
WEDNESDAY NIGHT THROUGH TUESDAY...DAVIS