Area Forecast Discussion
Issued by NWS Milwaukee/Sullivan, WI

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FXUS63 KMKX 141627
AFDMKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
1127 AM CDT MON APR 14 2014

.UPDATE...MID LEVEL TROUGH AXIS STILL TO OUR WEST AND STILL SOME
SHORTWAVE ENERGY ROTATING THROUGH AHEAD OF IT. 88-D SHOWING UPTICK
ON RETURNS ACROSS WRN WI AND SOME DEVELOPING IN NRN IL. WILL GO
WITH HIGH CONFIDENT PRECIP OCCURRENCE BUT LOW ON MEASURING. WITH
LOWER LEVEL WET BULB CONSIDERATIONS AND CHILLY SURFACE TEMPS BULK
OF PRECIP THAT OCCURS LOOKS TO BE OF THE FROZEN VARIETY. LOW LEVEL
COLD ADVECTION MAKING FOR A BLUSTERY DAY WITH UNPLEASANT WIND
CHILLS.

PC

&&

.AVIATION/18Z TAFS/...STILL SOME LINGERING VERY LGT PRECIP LIKELY
TO HANG AROUND INTO THE EVENING WITH SLOW ARRIVAL OF MID LEVEL
TROUGH AXIS. PLENTY OF MVFR CIGS AROUND AND EXPECT THIS TO PERSIST
INTO THE EVENING HOURS. MOS TRENDS DON/T LOOK TOO BAD IN THIS
REGARD. WINDS WILL GRADUALLY SLACKEN AS WELL AS LOW CONTINUES TO
PULL FURTHER AWAY AND GRADIENT SLACKENS.

PC

&&

.MARINE...WILL BE TRANSITIONING TO SMALL CRAFT ADVISORY WHEN GALE
WARNING EXPIRES AT 18Z. THIS WILL LIKELY LAST WELL INTO THE
EVENING HOURS.

PC

&&

.PREV DISCUSSION... /ISSUED 335 AM CDT MON APR 14 2014/

TODAY AND TONIGHT...FORECAST CONFIDENCE IS MEDIUM.

MAIN MID LEVEL SHORT WAVE OVER SCNTRL IOWA EARLY THIS MORNING...WILL
MOVE INTO NCNTRL IL BY 12Z...CONTINUING NORTHEAST THEREAFTER. THIS
WILL BRING A FAIRLY RAPID END TO THE PRECIP ONCE THE AXIS CLEARS TO
THE EAST. WSR-88D DUAL POL CORRELATION COEFFICIENT DATA SHOWING THE
TRANSITION FROM LIQUID TO SNOW OCCURRING ACROSS THE NORTHWEST CWA
BETWEEN 06-07Z THIS MORNING AND THIS CHANGE-OVER WILL CONTINUE TO
PROGRESS EAST THIS MORNING...REACHING MILWAUKEE BY 12-13Z THIS
MORNING. THE BEST CHANCE FOR A 1 TO 2 INCH ACCUMULATION WILL BE WEST
AND NORTH OF MADISON AND THIS SHOULD MAINLY OCCUR ON GRASSY AREAS.
PAVEMENT TEMPERATURES WILL BE WARM ENOUGH INITIALLY TO MELT THE
SNOW...BUT SOME SLUSHY ACCUMS ARE EVENTUALLY POSSIBLE ON ROADS...SO
BE PREPARED FOR THAT DURING THE MORNING COMMUTE.  THE PRECIP SHOULD
COME TO AN END BY LATE MORNING...WITH MUCH OF THE AFTERNOON DRY. THE
EXCEPTION...A DEEP MID LEVEL TROF WILL PROGRESS ACROSS THE
BADGERLAND TONIGHT. ALTHOUGH THE BULK OF ANY PRECIP OUT AHEAD OF THE
THIS TROF WILL BE WELL TO OUR SOUTH AND EAST...THE FAR WESTERN EDGE
OF A PRECIP SHIELD COULD CLIP FAR SOUTHEAST WISCONSIN LATE THIS
AFTERNOON AND EVENING. THAT WOULD BE A RAIN/SNOW MIX OR ALL
SNOW...BUT LITTLE OR NO ACCUMULATION IS EXPECTED. OTHERWISE...THE
REST OF THE FORECAST AREA WILL BE QUIET.

THE STRONG AND GUSTY WINDS THIS MORNING WILL SUBSIDE A BIT BY MID
MORNING AS THE SURFACE LOW MOVING ACROSS NORTHERN ILLINOIS REACHES
CENTRAL OR NORTHERN LOWER MICHIGAN BY 12Z.  THE STRONGEST WINDS WILL
BE FELT UP UNTIL A FEW HOURS AFTER SUNRISE...SUBSIDING THRU THE DAY.

EXPECT A VERY CHILLY DAY ACROSS SOUTHERN WISCONSIN WITH HIGHS
HOLDING DOWN IN THE MID TO UPPER 30S UNDER STRONG COLD ADVECTION.
RIDGING MOVING IN TONIGHT WILL BE ACCOMPANIED BY A VERY COLD AIRMASS
FOR THIS TIME OF YEAR. TEMPS WILL FALL INTO THE UPPER TEENS TO LOWER
20S...COLDEST NORTHWEST OF MADISON. THE COMPLICATING FACTOR TO TEMPS
TONIGHT WILL BE THE DEGREE OF CLEARING WE SEE.  THAT UPPER TROF
MOVING THROUGH COULD DELAY THE CLEARING A BIT LONGER...IN WHICH CASE
TEMPS MIGHT BE ABLE TO STAY A BIT MORE ELEVATED.  EARLIER CLEARING
COULD BRING LOWER TEMPS THAN FORECAST.

TUESDAY AND WEDNESDAY...FORECAST CONFIDENCE...HIGH

IT SHOULD BE DRY TUESDAY AS HIGH PRESSURE SLIDES THROUGH. THOUGH
TEMPS ALOFT WILL BE WARM ADVECTING THROUGH THE DAY...THE COLDEST
AIRMASS WILL BE OVERHEAD AT DAYBREAK. AFTERNOON HIGHS ARE THUS
EXPECTED TO STRUGGLE ONCE AGAIN INTO THE UPPER 30S TO AROUND 40.

THERE WILL BE PRECIP CHANCES MAINLY IN THE NORTHWEST WEDNESDAY.
LOOKS LIKE PRECIP SHOULD BE RAIN...THOUGH A LITTLE MIX WITH SNOW
IS POSSIBLE EARLY IN THE MORNING. SHOULD SEE MILDER TEMPS UNDER
BREEZY SOUTH WINDS...UP TO THE LOW 50S EXCEPT FOR IN THE EAST DUE
TO AN EASTERLY COMPONENT TO THE WINDS.

THURSDAY THROUGH SUNDAY...FORECAST CONFIDENCE...LOW

USED MAINLY A CONSENSUS APPROACH FOR THE THURSDAY-SUNDAY
FORECAST...DUE TO THE SIGNIFICANT MODEL DIFFERENCES IN STORM
TRACK...TEMPERATURES...AND RESULTANT PRECIP TYPE. THE UNCERTAINTY
CAN BE SUMMARIZED BY THE FACT THAT YESTERDAY THE GFS HAS SNOW
ACCUMS WEST ON FRIDAY...WHILE THE ECMWF WAS MILDER AND MAINLY DRY.
NOW THE GFS IS MILDER WITH RAIN CHANCES...WHILE THE ECMWF IS
COLDER WITH SOME LIGHT SNOW ACCUMS. ADDITIONALLY MODELS WERE
SHOWING MILDER BY THE WEEKEND...BUT HAVE NOW TURNED COLDER.
NEEDLESS TO SAY...NOT A LOT OF CONFIDENCE IN THE EXTENDED
FORECAST.

OVERALL...MODELS DO AGREE SOMEWHAT ON NEAR NORMAL TEMPS
THURSDAY...FOLLOWED BY BELOW NORMAL TEMPS AGAIN FRIDAY THROUGH
SUNDAY. BEST PRECIP CHANCES LOOK TO BE THU NIGHT THROUGH FRI NIGHT
AS LOW PRESSURE PASSES THROUGH.

HYDROLOGY...

WILL GO AHEAD AND CANCEL THE FLOOD WATCH EARLY.  A CALL AROUND TO
COUNTIES HARDEST HIT INDICATES NO MAJOR ISSUES. RIVERS ARE ON THE
RISE...HOWEVER AND SOME ARE EXPECTED TO REACH FLOOD STAGE OVER THE
NEXT 24 TO 48 HOURS...THESE ARE ALREADY BEING HANDLED THROUGH
INDIVIDUAL FLOOD WARNINGS FOR THOSE AREAS.  RAINFALL AMOUNTS OVER
THE LAST 48HRS RANGE FROM AROUND 2 INCHES IN MILWAUKEE TO JUST OVER
SIX INCHES IN LONE ROCK. THE HARDEST HIT AREA HAS BEEN NORTH AND
WEST OF A PORT WASHINGTON TO MADISON TO DODGEVILLE LINE.

AVIATION/00Z TAFS/...LOOK FOR THE PRECIPITATION TO DIMINISH QUICKLY
AFTER 12Z. KMSN WILL LIKELY BE ALL SNOW BY TAF ISSUANCE TIME...BUT
IT WILL BE DIMINISHING QUICKLY...SO LESS THAN AN INCH OF
ACCUMULATION EXPECTED AND MAINLY ON GRASSY AREAS. PAVEMENT
TEMPERATURES SHOULD BE TOO WARM FOR ACCUMULATION ON HARD SURFACES.
KMKE/KUES/KENW WILL LIKELY TRANSITION TOO LATE FOR ANYTHING
MEASURABLE AS THE PRECIP WILL BE NEARING ITS END. IFR CIGS/VSBYS
WILL IMPROVE TO MVFR LEVELS THIS MORNING WITH EVENTUAL CLEARING
FROM WEST TO EAST TONIGHT AS HIGH PRESSURE BUILDS IN. THE STRONG
AND GUSTY NORTHERLY WINDS WILL BE AT THEIR STRONGEST AT TAF
ISSUANCE...THEN DIMINISHING THROUGH THE DAY.


MARINE...A GALE WARNING IS IN EFFECT UNTIL 1 PM FOR STRONG
NORTHERLY WINDS AND LARGE WAVES. WINDS WILL DIMINISH THROUGH THE
AFTERNOON...SO THE GALE WARNING WILL BE DOWNGRADED TO SMALL CRAFT
ADVISORY ONCE THE GALE EXPIRES.  SMALL CRAFT ADVISORY CONDITIONS
WILL LIKELY PERSIST THROUGH ABOUT MID OR LATE EVENING.

SMALL CRAFT ADVISORY CONDITIONS ARE EXPECTED AGAIN WED INTO WED
NIGHT FOR BRISK SOUTHEAST WINDS AHEAD OF STRONG LOW PRESSURE
APPROACHING THE REGION.

&&

.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...GALE WARNING UNTIL 1 PM CDT THIS AFTERNOON FOR LMZ643>646.

&&

$$
TODAY/TONIGHT AND AVIATION/MARINE...DAVIS
TUESDAY THROUGH SUNDAY...DDV



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