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000
FXUS63 KMKX 201519 AAA
AFDMKX

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
1019 AM CDT MON MAY 20 2013

.UPDATE...MAIN BAND OF CLOUDINESS IS SHIFTING EASTWARD THIS
MORNING...WHICH SHOULD ALLOW FOR A GOOD AMOUNT OF SUNSHINE INTO
THIS AFTERNOON. HIGH TEMPS WERE BUMPED UP A BIT OVERNIGHT AND
STILL SEEM REASONABLE.

BIGGEST CONCERN TODAY INTO TONIGHT IS TIMING AND STRENGTH OF
EXPECTED THUNDERSTORMS. SPC IS MAINTAINING A SLIGHT RISK FOR
SEVERE STORMS ACROSS THE FORECAST AREA FOR TODAY. LATEST NAM AND
RAP SOUNDINGS AGREE THAT THE ENVIRONMENT STILL LOOKS FAVORABLE FOR
STRONG TO SEVERE STORMS. WITH THE EXPECTED SUNSHINE...SHOULD SEE
SFC BASED CAPE GET IN THE 1000-1500 J/KG RANGE BY THIS AFTERNOON.
ADDITIONALLY...PLENTY OF 0-6 KM BULK SHEAR...GENERALLY 35-45 KT.
PLENTY OF MOISTURE AS WELL...WITH PRECIPITABLE WATER VALUES AROUND
1.25 INCHES...ABOVE CLIMATOLOGICAL NORMALS.

WITH A DECENT ENVIRONMENTAL SETUP...WILL JUST BE WAITING FOR THE
TRIGGER. LATEST WATER VAPOR INDICATING A SHORTWAVE TO THE
SOUTHWEST...WITH SOME ASSOCIATED CONVECTION OVER EASTERN KANSAS
AND WESTERN MISSOURI. TIMING OF THIS ACTIVITY TO THE SOUTHWEST
ALONG WITH LATEST HRRR AND LOCAL WRF4L MODEL INDICATE THE BEST
CHANCE FOR STORMS TO MOVE IN TODAY WILL BE IN THE DURING THE LATE
AFTERNOON AND EARLY EVENING HOURS.

&&

.AVIATION/18Z TAFS/...VFR CONDITIONS ARE EXPECTED TO CONTINUE
THROUGH TUESDAY...THOUGH LOWER CIGS/VSBYS POSSIBLE IN ANY
THUNDERSTORMS. BIG ISSUE THROUGH TOMORROW WILL BE TIMING ROUNDS OF
THUNDERSTORMS. LOOKS QUIET THIS MORNING...BUT WILL LIKELY SEE
STORMS DEVELOP THIS AFTERNOON OR EVENING...WITH STORMS THEN LIKELY
AT TIMES THROUGH TUESDAY.

&&

.PREV DISCUSSION... /ISSUED 329 AM CDT MON MAY 20 2013/

TODAY AND TONIGHT...FORECAST CONFIDENCE - MEDIUM.

ATMOSPHERE HAS BEEN STABILIZED SOMEWHAT BY OVERNIGHT CONVECTION BUT
LIKELY TO TURN UNSTABLE ONCE AGAIN LATER THIS MORNING AND AFTERNOON
DUE TO RETURNING SUNSHINE AND LINGERING HIGHER RELATIVE HUMIDITY.
PRECIPITABLE WATER VALUES CONTINUE AROUND 1.5 INCHES. UPPER JET
CONTINUES TO PIVOT SLOWLY EWD INTO WI TODAY RESULTING IN SOME
ENHANCED UPWARD VERTICAL MOTION.  DIFFICULT TO DISCERN INDIVIDUAL
SHORT WAVES ROTATING AROUND UPPER LOW OVER THE PLAINS BUT ALL SHORT
TERM GUIDANCE CONTINUES TO INDICATE WEAK WAVES ROTATING AROUND
PARENT LOW INTO THE REGION THROUGH TONIGHT.  LOW LEVEL JET WEAKENS
THIS MRNG BUT STRENGTHENS AGAIN THIS AFTERNOON AND EVENING.  HENCE
WL CONTINUE CHANCE/SCATTERED LEVEL POPS THROUGH TODAY...AND BEEF UP TO
LIKELY WORDING FOR TONIGHT. AGGREGATE SEVERE PARAMETER INDEX REMAINS
HIGH FOR POTENTIAL SEVERE WEATHER LATE THIS AFTERNOON AND EVENING.

TUESDAY - CONFIDENCE...MEDIUM
UPPER LOW CONTINUES TO SPIN TO OUR WEST ACRS SE SD/NE NEB/SW MN/NW
IA. SRN WI WILL REMAIN SITUATED IN A SOUTHWEST UPPER FLOW WITH
SHORTWAVES MOVING THROUGH. 850 THERMAL RIDGE SHIFTS EAST. SYSTEM
OCCLUDES...BUT ENOUGH COLD AIR UPSTAIRS AND LINGERING LOW LEVEL
INSTABILITY TO KEEP THUNDERSTORM POTENTIAL HIGH. GFS AND NAM
SOUNDINGS ARE NOT SHOWING TREMENDOUS CAPE. 850 JET AXIS PLACES SE WI
IN FAVORABLE LEFT FRONT QUAD REGION AND 250 MILLIBAR JET ACROSS WI.
SLIGHT RISK STILL LOOKS OK AT THIS POINT.

WEDNESDAY - CONFIDENCE...MEDIUM
500 MILLIBAR FINALLY PLODS ACROSS THE AREA. NAM AND GFS REALLY CRANK
OUT THE QPF WITH SECONDARY SURFACE LOW THAT STRENGTHENS A BIT FROM
NRN IL INTO LOWER MI. ALL MODELS SUGGEST ENHANCED LOWER LEVEL
CONVERGENCE WITH 850 LOW/TROUGH. 00Z CAME IN WITH HIGHER QPF AMOUNTS
IN SRN WI...AGREEING WITH THE 00Z OUTPUT FROM THE NAM AND GFS. 12Z
ECMWF HAD THE BETTER QPF ACRS NRN WI. MODELS SUGGEST A BIT OF
LINGERING UPPER JET ACTION ACRS ERN WI MAINLY IN THE MORNING.

THURSDAY - CONFIDENCE...MEDIUM
LINGERING LOW LEVEL TROUGH KEEPS SHRA CHANCES AROUND...THOUGH HIGH
GRADUALLY BUILDS IN WITH TIME. NNE 850 FLOW DEVELOPS WITH COOL POOL
SETTLING IN.

FRIDAY - CONFIDENCE...MEDIUM
HIGH PRESSURE WILL DOMINATE. 12Z ECMWF SHOWS 3C AT 850 WHILE 00Z GFS
SHOWING 10C. EITHER WAY...LOOKING AT A QUIET DAY.

SATURDAY AND SUNDAY - CONFIDENCE...LOW
MODELS DIVERGING WITH TIMING/EVOLUTION OF WARM AIR ADVECTION/RIDGE
RIDER REGIME. BAROCLINIC ZONE POSITION IS IN QUESTION TOO. WILL LET
THE ALLBLEND POPS/TEMPS HANDLE THIS FOR NOW UNTIL MODELS COME INTO
BETTER AGREEMENT.

AVIATION/12Z TAFS/...POTENTIAL PERIOD OF LOW STRATUS IN WRN AREAS EARLY
THIS MRNG DUE TO BOUNDARY LAYER MIXING AND OVERNIGHT RAINFALL. OTHERWISE
EXPECT MOSTLY VFR CONDITIONS INTERRUPTED BY PASSING THUNDERSTORMS WITH
THE BEST CHANCE THIS AFTERNOON AND TONIGHT.

MARINE...WITH DEWPOINTS IN THE 60S LIKELY TO MOVE ACROSS THE NEARSHORE
WATERS...SOME PATCHY FOG AND HAZE LIKELY TO DEVELOP.  COOLER WATERS
REMAIN TOWARD THE OPEN WATERS WITH SHALLOWER NEAR SHORE WATERS MORE
IN THE MIDDLE 50S TO AROUND 60.  HENCE WL HOLD OFF ON INTRODUCING
DENSE FOG AT THIS TIME...BUT IS A CONCERN FARTHER AWAY FROM SHORE.

&&

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

$$

UPDATE...DDV
TODAY/TONIGHT AND AVIATION/MARINE...MBK
TUESDAY THROUGH SUNDAY...COLLAR