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000
FXUS63 KMKX 120200
AFDMKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
900 PM CDT TUE MAR 11 2014

.UPDATE...RADAR TRENDS AND DRYING FROM THE NORTH SUGGESTS MOST OF
THE PCPN FROM THE DEVELOPING LOW TO THE SOUTH WILL MISS SRN WI.
CURRENT RAIN AND SNOW FROM JEFFERSON COUNTY EWD TO MILWAUKEE WILL
LIKELY END IN A HOUR OR TWO. THE WI COUNTIES BORDERING IL WILL SEE
THE PCPN LONGER BUT SHOULD REMAIN VERY LIGHT. REDUCED SNOW TOTALS
TO ONE INCH IN THE KENOSHA AREA TO LESS THAN ONE HALF INCH TOWARD
MILWAUKEE. THE PASSAGE OF AN INVERTED SFC TROUGH THAT WILL
APPROACH FROM THE NE MAY SET OFF SNOW SHOWERS ALONG IT LATE
TONIGHT MAINLY OVER THE NRN AND WRN CWA...BUT LOW LEVEL MOISTURE
IS LIMITED.

&&

.AVIATION/06Z TAFS/...COMING LATER.


&&

.PREV DISCUSSION... /ISSUED 328 PM CDT TUE MAR 11 2014/

SHORT TERM...

TONIGHT AND WEDNESDAY...FORECAST CONFIDENCE IS HIGH.

AREA OF LIGHT RAIN CURRENTLY OVER CENTRAL AND SOUTHERN PORTIONS OF
THE AREA PER RADAR IMAGERY. THIS WILL CONTINUE TO SHIFT SLOWLY
EASTWARD INTO THE EVENING. THIS IS ASSOCIATED WITH MAIN BAND OF 850
MB TO 700 MB FRONTOGENESIS RESPONSE. UPPER LEVEL DIVERGENCE FROM
RIGHT REAR QUADRANT OF JET STREAK ALSO HELPING OUT.

LATEST MESOSCALE MODELS AND 12Z SYNOPTIC MODELS ARE IN GENERAL
AGREEMENT WITH TAKING THIS BAND OF LIGHT RAIN GRADUALLY
SOUTHEASTWARD THROUGH THE AREA THROUGH THE EVENING. AS THIS BAND
SHIFTS SOUTHEASTWARD...COLD AIR ADVECTION OCCURRING IN THE LOW
LEVELS WILL ALLOW FOR A MIX OF LIGHT RAIN AND LIGHT SNOW TO OCCUR
FROM NORTH TO SOUTH. NOT EXPECTING ANY ACCUMULATION OF SNOW THROUGH
00Z WEDNESDAY...BUT THIS MAY AFFECT THE TAIL END OF THE EVENING RUSH
HOUR PERIOD IN MILWAUKEE AND MADISON.

THIS BAND BECOMES ALL LIGHT SNOW AS IT LINGERS ACROSS THE SOUTHEAST
COUNTIES BY MID EVENING...AND IN KENOSHA COUNTY THROUGH MOST OF
TONIGHT. THIS IS IN RESPONSE TO THE STRONG LOW PRESSURE SYSTEM
PASSING SOUTH OF THE REGION...CAUSING THE FRONTOGENESIS RESPONSE TO
BECOME ORIENTED MORE SOUTHWEST TO NORTHEAST FROM NORTHERN ILLINOIS
INTO SOUTHERN LAKE MICHIGAN.

12Z MODELS SUGGESTING THE HEAVIEST QPF WILL REMAIN JUST SOUTH OF
KENOSHA COUNTY TONIGHT. GFS SHOWS A LOT MORE QPF IN THE SOUTHEAST
THAN THE ECMWF/CANADIAN...WITH THE NAM SHOWING LITTLE TO NONE.
LEANED TOWARD THE ECMWF/CANADIAN AMOUNTS...WHICH SHOULD BRING A 1 TO
2 INCH ACCUMULATION IN THE SOUTHEAST COUNTIES...LOWER TO THE
NORTHWEST.

GUSTY NORTH TO NORTHEAST WINDS DEVELOP DURING THE NIGHT...CAUSING
SOME BLOWING SNOW IN THE FAR SOUTHEAST COUNTIES. HOWEVER...WILL NOT
ISSUE AN ADVISORY FOR RACINE AND KENOSHA COUNTIES AT THIS TIME...AS
WET NATURE OF SNOW SHOULD KEEP VISIBILITY REDUCTIONS TO AROUND 6
MILES AT WORST.

WEDNESDAY NIGHT AND THURSDAY...FORECAST CONFIDENCE...HIGH

THE STRONG MID/UPPER TROUGH MOVES ACROSS THE NORTHEAST U.S.
THURSDAY WITH A NORTHWEST FLOW ACROSS WISCONSIN BEHIND THE TROUGH.

TEMPERATURES SHOULD DROP EARLY WEDNESDAY NIGHT BEFORE WARM
ADVECTION BEGINS LATER WEDNESDAY NIGHT AND ESPECIALLY THURSDAY AS
LOW PRESSURE MOVES ACROSS SOUTH CENTRAL CANADA. THE 12Z NAM
SATURATES AT 700 MB LATE WEDNESDAY NIGHT...SO EXPECT MIDNIGHT
LOWS AND THEN A SLOW RISE.

MOST MODELS BRING A FEW HUNDREDTHS OF PRECIPITATION THURSDAY
MORNING BUT LASTS A BIT LONGER OVER THE FAR EAST. THE 285 KELVIN
LAYER SHOWS MODERATE LIFT AND SATURATION PRESSURE DEFICITS OF
ZERO. TEMPERATURES ARE COLD ENOUGH FOR SNOW...BEFORE THICKNESS AND
850 TEMPERATURES WARM.

THURSDAY NIGHT AND FRIDAY...FORECAST CONFIDENCE...HIGH

A NORTHERN STREAM SHORTWAVE MOVES ACROSS THE DAKOTAS THURSDAY
EVENING AND INTO THE UPPER GREAT LAKES FRIDAY.

FRIDAY MORNING SHOULD START MILD AS A SURFACE LOW MOVES ACROSS THE
LAKE SUPERIOR AREA. THEN COLD ADVECTION BEGINS FRIDAY AFTERNOON
AS THE LOW MOVES JUST NORTH OF LAKE HURON.

LONG TERM...

FRIDAY NIGHT AND SATURDAY...FORECAST CONFIDENCE...HIGH

A LARGE UPPER LEVEL TROUGH EXTENDS OVER THE HUDSON BAY AREA
WITH ANOTHER SHORTWAVE DROPPING SOUTHEAST TOWARDS THE UPPER
GREAT LAKES.

A SURFACE TROUGH AXIS DROPS INTO SOUTHERN WISCONSIN
FRIDAY NIGHT BEFORE HIGH PRESSURE BUILDS TOWARDS LAKE SUPERIOR
SATURDAY AFTERNOON. 850 MB RH IS HIGH AND EXPECT A STRATOCUMULUS
SHIELD WITH POSSIBLE SNOW SHOWERS.

SUNDAY AND MONDAY...FORECAST CONFIDENCE...MEDIUM

A LARGE UPPER LEVEL TROUGH PERSISTS JUST EAST OF HUDSON BAY.
THE 00Z ECMWF HAS A MORE EAST WEST STRUCTURE...WHILE THE 12Z GFS
STILL HAS THE TROUGH AXIS ACROSS THE EASTERN GREAT LAKES.

EITHER WAY BOTH MODELS HAVE SURFACE HIGH PRESSURE EXTENDING INTO
THE GREAT LAKES...WITH COLDER TEMPERATURES SUNDAY AND A SOUTHWEST
FLOW AND WARM ADVECTION BEGINNING ON MONDAY.

TUESDAY...FORECAST CONFIDENCE...MEDIUM

A SHORTWAVE MOVES ACROSS THE UPPER MISSISSIPPI VALLEY.

ON TUESDAY LOW PRESSURE MOVES ACROSS THE LAKE SUPERIOR REGION ON
THE GFS...BUT FARTHER SOUTH ACROSS WISCONSIN ON THE 00Z ECMWF.
THICKNESS VALUES SHOULD BE MAINLY RAIN OVER THE SOUTH.

AVIATION/00Z TAFS/...

VFR CONDITIONS WITH LIGHT RAIN IS EXPECTED ACROSS TAF SITES INTO
EARLY EVENING. MVFR CEILINGS AND VISIBILITIES ARE EVENTUALLY
EXPECTED WITH THE BAND OF LIGHT RAIN BY 00Z WEDNESDAY. SHOULD SEE
LIGHT SNOW MIX IN WITH THE LIGHT RAIN BETWEEN 00Z AND
03Z WEDNESDAY...THEN BECOME ALL LIGHT SNOW.

THE LIGHT SNOW WITH VISIBILITIES AROUND ALTERNATE MINIMUMS WILL
LINGER UNTIL AROUND 04Z TO 05Z WEDNESDAY AT MADISON...AROUND 07Z AT
WAUKESHA/MILWAUKEE...AND UNTIL AROUND 10Z WEDNESDAY AT KENOSHA.
LIGHT SNOWFALL RATES OF 1/10 TO 1/4 OF AN INCH PER HOUR ARE
EXPECTED...WITH TOTALS OF 1 TO 2 INCHES AT THE EASTERN SITES...AND
UNDER 1 INCH AT MADISON.

NORTH NORTHEAST WINDS WILL BECOME GUSTY DURING THE
EVENING...BECOMING NORTH AND REMAINING GUSTY ON WEDNESDAY. GUSTS TO
30 TO 33 KNOTS ARE POSSIBLE AT THE EASTERN SITES LATER THIS EVENING
INTO THE OVERNIGHT HOURS...AND TO AROUND 25 KNOTS AT MADISON. NOT
EXPECTING VISIBILITY REDUCTIONS BELOW 6 MILES FROM ANY BLOWING
SNOW...AS THE SNOW WILL BE THE WET AND HEAVY TYPE.

MARINE...

GALE WARNING CONTINUES ACROSS THE NEARSHORE WATERS FROM 03Z TO 17Z
WEDNESDAY. STRONG PRESSURE GRADIENT WILL DEVELOP THIS EVENING AND
LINGER INTO EARLY WEDNESDAY MORNING...AS STRONG LOW PRESSURE PASSES
BY TO THE SOUTH OF THE REGION. THIS WILL CAUSE GUSTY NORTH NORTHEAST
WINDS TONIGHT...BECOMING NORTH ON WEDNESDAY. GUSTS OF 35 TO 40 KNOTS
ARE EXPECTED DURING THE GALE WARNING PERIOD.

ICE COVER HAS BROKEN UP ACROSS THE NEARSHORE WATERS WITH THE MILD
TEMPERATURES THE PAST FEW DAYS PER RECENT MODIS SATELLITE IMAGERY.
SO...EXPECT HIGH WAVES UP TO 5 TO 10 FEET TO DEVELOP TONIGHT INTO
WEDNESDAY MORNING.

A SMALL CRAFT ADVISORY WILL BE NEEDED WEDNESDAY AFTERNOON AND
EVENING...AS THE PRESSURE GRADIENT SLOWLY WEAKENS AND GUSTY NORTH
WINDS REMAIN. HIGH WAVES WILL SLOWLY SUBSIDE DURING THIS TIME.

&&

.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...GALE WARNING UNTIL NOON CDT WEDNESDAY FOR LMZ643>646.

&&

$$

UPDATE...GEHRING
TONIGHT/WEDNESDAY AND AVIATION/MARINE...WOOD
WEDNESDAY NIGHT THROUGH TUESDAY...HENTZ