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000
FXUS63 KMKX 050930
AFDMKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
330 AM CST THU DEC 5 2013

.TODAY AND TONIGHT...FORECAST CONFIDENCE IS MEDIUM TO HIGH.

THE MAIN 250 MB TROUGH IS OVER THE WESTERN U.S. WITH A 160 KNOT
JET MAX MOVING ACROSS WISCONSIN TODAY. A SECOND JET MAX FORMS FROM
EASTERN KANSAS TO SOUTHEAST WISCONSIN TONIGHT. MOST OF THE UPPER
DIVERGENCE STAYS SOUTH OF THE FORECAST AREA LATER TODAY AND
TONIGHT.

850/700 MB COLD AIR ADVECTION CONTINUES THROUGH TODAY AND
TONIGHT. 700 MB DOWNWARD MOTION TODAY BECOMES NEUTRAL TONIGHT. 700
MB LAYERS WILL BE DRY BY SUNRISE TODAY...BUT INCREASES AGAIN
TOWARD KENOSHA LATE TONIGHT. 850 MB RH ALSO DRIES BY SUNRISE AND
REMAINS DRY THROUGH TONIGHT. 950 MB RH STAYS RATHER HIGH BUT DRIES
A LITTLE TODAY. AREAS NEAR THE ILLINOIS BORDER BEGIN TO DRY MORE
THIS AFTERNOON AND EVENING, NAM FORECAST SOUNDINGS SHOW THE LOW
LEVEL MOIST LAYER BECOMING RATHER SHALLOW THIS AFTERNOON AND THE
LOW CLOUDS SHOULD BECOME MORE SCATTERED. HOWEVER JET CIRRUS WOULD
KEEP SOUTHEAST AREAS CLOUDY. SOME FLURRIES POSSIBLE THIS MORNING
WITH THE COLD AIR ADVECTION AND MOIST LOW LEVELS.

MAIN CONCERN WILL BE FALLING TEMPERATURES AND WINDS. THIS WILL
DROP WIND CHILLS TO THE TEENS SOUTHEAST AND SINGLE DIGITS
NORTHWEST OF MADISON TODAY. WIND CHILLS SHOULD DROP TO ZERO TO 5
BELOW TONIGHT. THE WINDS WILL SLOWLY DIMINISH TONIGHT.

.SHORT TERM...FRIDAY THROUGH SATURDAY NIGHT...FORECAST CONFIDENCE
IS HIGH.

SHORT TERM MODELS ARE IN GOOD AGREEMENT WITH STRONG COLD AIR
ADVECTION CONTINUING FRIDAY AND FRIDAY NIGHT ACROSS THE AREA. THIS
IS IN RESPONSE TO STRONG HIGH PRESSURE MOVING SLOWLY EAST ACROSS
THE NORTHERN PLAINS. THE HIGH THEN SHIFTS EAST ACROSS AND EAST OF
THE AREA SATURDAY AND SATURDAY NIGHT. AREA FORECAST SOUNDINGS ARE
FAIRLY DRY ACROSS THE AREA...WITH SOME HIGH CLOUDS MOVING INTO THE
AREA SATURDAY NIGHT. THUS...QUIET WEATHER IS EXPECTED DURING THIS
PERIOD.

THE MAIN ISSUE WILL CONTINUE TO BE THE COLD TEMPERATURES. MODEL
925MB TEMPERATURE FIELDS AND 2 METER TEMPERATURES SUGGEST HIGHS
ONLY IN THE TEENS FRIDAY AND SATURDAY. LOWS WILL BE IN THE SINGLE
DIGITS BELOW ZERO TO ABOVE ZERO FRIDAY NIGHT...ONLY IMPROVING
SLIGHTLY SATURDAY NIGHT.

&&

.LONG TERM...SUNDAY THROUGH WEDNESDAY...FORECAST CONFIDENCE IS
MEDIUM TO HIGH.

GFS/ECMWF CONTINUE TO SHOW ACCUMULATING SNOW POTENTIAL FOR LATER
SUNDAY THROUGH LATE SUNDAY NIGHT/EARLY MONDAY MORNING ACROSS THE
AREA. THEY BRING LOW LEVEL WARM AIR ADVECTION INTO THE AREA
SUNDAY...WITH STRONG 500MB VORTICITY MAXIMA THROUGH THE AREA
SUNDAY NIGHT. DECENT 700 MB TO 500 MB FRONTOGENESIS PASSES THROUGH
THE FAR SOUTHEASTERN PORTIONS OF THE AREA SUNDAY NIGHT ON THE GFS.
GFS FORECAST SOUNDINGS SHOWING A SATURATED AIR COLUMN LATER SUNDAY
THROUGH SUNDAY NIGHT. GOOD UPWARD VERTICAL MOTION IN THE DEEP
DENDRITE SNOW GROWTH ZONE IS ALSO SEEN...BEST AND DEEPEST ON
SUNDAY NIGHT.

WILL CONTINUE HIGH POPS FOR SUNDAY NIGHT...TRENDING UPWARD SUNDAY
AND DOWNWARD MONDAY MORNING. COLD AIRMASS IN PLACE DURING THIS
TIME SHOULD KEEP SNOW TO LIQUID RATIOS FROM THE 18 TO 1 TO THE 20
TO 1 RANGE. LIQUID EQUIVALENT AMOUNTS IN THE 0.20 TO 0.30 INCH
RANGE SUGGEST SNOWFALL AMOUNTS OF 3 TO 6 INCHES POSSIBLE. STAY
TUNED TO LATER FORECASTS FOR MORE INFORMATION. WILL CONTINUE
MENTION SNOW LIKELIHOOD IN HAZARDOUS WEATHER OUTLOOK. COLD
TEMPERATURES WILL LINGER SUNDAY INTO MONDAY...WITH A REINFORCING
PUSH OF COLD AIR ADVECTION MONDAY.

GFS/ECMWF THEN HAS A DECENT 500 MB SHORTWAVE TROUGH SLIDING EAST
THROUGH THE REGION LATE MONDAY AND MONDAY NIGHT. GFS SUGGESTS
THIS SYSTEM WOULD HAVE ENOUGH UPWARD VERTICAL MOTION AND MOISTURE
TO BRING MORE CHANCES FOR LIGHT SNOW. QPF IS LIGHT...WITH MOST
JUST NORTH OF THE AREA. KEPT CHANCE POPS GOING FOR MONDAY.

SOME DIFFERENCES EXIST BEYOND TUESDAY IN THE MODELS...SO USED
CONSENSUS POPS AND TEMPERATURES FOR TUESDAY INTO WEDNESDAY.
TEMPERATURES WILL CONTINUE TO BE BELOW SEASONAL NORMALS.

&&

.AVIATION/12Z TAFS/...

MVFR CIGS THIS MORNING BEFORE LOW CLOUDS BEGIN TO SCATTER OUT
THIS AFTERNOON...AS THE INVERSION LOWERS AND THE MOIST LAYER
BECOMES MORE SHALLOW AND DRIER AIR ADVECTS IN FROM THE WEST. BRISK
WEST WINDS TODAY WITH SOME GUSTS UP TO 30 KNOTS THIS MORNING.
WINDS WILL SLOWLY DIMINISH LATER THIS AFTERNOON AND TONIGHT AS THE
STRONG LOW NEAR LAKE SUPERIOR MOVES NORTHEAST TOWARD JAMES BAY
CANADA.

&&

.MARINE...

SMALL CRAFT ADVISORY CONDITIONS TODAY AND TONIGHT WITH BRISK WEST
WINDS. A FEW GALE GUSTS POSSIBLE THIS MORNING. WINDS WILL SLOWLY
DIMINISH TONIGHT AS THE STRONG LOW NEAR LAKE SUPERIOR MOVES
NORTHEAST TOWARD JAMES BAY CANADA.

&&

.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 6 AM CST FRIDAY FOR LMZ643>646.

&&

$$

TODAY/TONIGHT AND AVIATION/MARINE...HENTZ
FRIDAY THROUGH WEDNESDAY...WOOD