000
FXUS63 KMKX 171638 AAA
AFDMKX

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
1138 AM CDT MON JUN 17 2013

.UPDATE...

SUNNY AND WARM TODAY AHEAD OF A COLD FRONT. THE COLD FRONT SAGGING
DOWN THROUGH CENTRAL AND EVENTUALLY SOUTHERN WISCONSIN NOW LOOKS
LIKE IT WILL BE FAIRLY UNEVENTFUL IN TERMS OF WIDESPREAD
THUNDERSTORM PRODUCTION. SHORT TERM MODELS HAVE BACKED OFF ON PRECIP
COVERAGE. THE POTENTIAL IS STILL THERE FOR THE LATE AFTERNOON AS A
SHORTWAVE SLIDES DOWN THROUGH CENTRAL WI. THERE CONTINUES TO BE
STRONG BULK SHEAR IN PLACE AND DECENT CAPE. KEPT THE
SCATTERED/ISOLATED THUNDERSTORM WORDING...BUT TRIED TO LIMIT THE
AREA AND THE TIME IN THE FORECAST FOR LATE AFTERNOON/EVENING IN
MAINLY SOUTH CENTRAL WI.

IF THUNDERSTORMS DEVELOP...A FEW COULD BECOME SEVERE WITH HAIL AND
DAMAGING WIND GUSTS. THE BEST CHANCE FOR THUNDERSTORMS SHOULD BE IN
SOUTH CENTRAL WI WHERE THE BETTER OVERALL DEEP FORCING COMES THROUGH
DURING THE DIURNALLY FAVORED TIME OF DAY. CONTINUE TO MONITOR AREA
RADARS FOR THUNDERSTORM TRENDS. SINCE THE NWS MKX RADAR IS
DOWN...THE MKE TERMINAL RADAR WILL BE HELPFUL...AS WELL AS
ARX...GRB...DVN AND LOT.

&&

.AVIATION/18Z TAFS/...

A LAKE BREEZE ALREADY THROUGH SHEBOYGAN AND PORT WASHINGTON IS
EXPECTED AT MKE AROUND 18Z TODAY AND PROBABLY IN ENW MID AFTERNOON
WITH A WEAK PRESSURE GRADIENT AS LOW PRESSURE MOVES ACROSS
WISCONSIN.

A COLD FRONT SAGGING SOUTHEAST THROUGH CENTRAL AND SOUTHERN
WISCONSIN TODAY AND TONIGHT WILL BE THE FOCUS OF A FEW SHOWERS AND
THUNDERSTORMS. THE THUNDERSTORMS SHOULD REMAIN ISOLATED...BUT WOULD
LIKELY BE ON THE STRONG SIDE. CONTINUE TO MONITOR AREA RADARS FOR
THUNDERSTORM TRENDS. SINCE THE NWS MKX RADAR IS DOWN...THE MKE
TERMINAL RADAR WILL BE HELPFUL...AS WELL AS ARX...GRB...DVN AND LOT.

THERE IS POTENTIAL FOR LOWER CLOUDS TO ACCOMPANY THE BACK EDGE OF
THE FRONT TONIGHT AS IT SLIDES ACROSS SOUTHERN WI AND EVENTUALLY
HANGS UP ACROSS NORTHEAST IOWA AND NORTHERN IL BY MID TUESDAY
MORNING.

&&

.PREV DISCUSSION... /ISSUED 428 AM CDT MON JUN 17 2013/

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

ISOLATED SHOWERS AND A THUNDERSTORM OR TWO OVER THE AREA BEING
FORCED BY DCVA AND WEAK 850MB F-GEN FORCING/CONVERGENCE AS WELL AS
ISENTROPIC OMEGA ON LEADING EDGE OF THERMAL RIDGE. THIS INITIAL
SURGE WILL EXIT TO THE EAST BY MID MORNING. PRECIPITATION CHANCES
THEN FOCUS ON COLD FRONT AND MID-LEVEL TROUGH THAT WILL BE SAGGING
THROUGH STATE TODAY INTO THIS EVENING. LAYER FRONTOGENETIC FORCING
BEST OVER CENTRAL WI THIS MORNING...THEN MOVES SOUTH THROUGH CWA
LATE THIS AFTERNOON/EVENING. GROWING INSTABILITY WITH SURFACE BASED
CAPE BETWEEN 700 AND 1000 J/KG AND 0-6KM SHEAR AROUND 40 KTS WITH
UNIDIRECTIONAL WINDS SO STORMS COULD ORGANIZE INTO LINEAR SEGMENTS
WITH GUSTY WINDS.

MID LEVEL TROUGH DOES NOT DRIVE THROUGH THE REGION WITH CHANNELED
VORTICITY OVER LINGERING BETWEEN INITIAL SHORT WAVE AS IT IS
ABSORBED INTO DEVELOPING CLOSED LOW OVER ERN CANADA AND NEXT WAVE
THAT REACHES SRN MN AROUND 12Z TUE. WEAK BUT PERSISTENT 700 MB
CONVERGENCE/OMEGA AND LOW LEVEL F-GEN WILL KEEP SLIGHT CHANCE POPS
IN FORECAST. LOSS OF DIURNAL HEATING REDUCES INSTABILITY SO MAINLY
SHOWERS. SHOULD SEE LOW TO MID 80 HIGHS BEFORE CLOUDS THICKEN
THIS AFTERNOON.

TUESDAY - CONFIDENCE...MEDIUM
LOW LEVEL THERMAL TROUGH WELL IN PLACE ACROSS THE AREA WITH
NORTHEAST WINDS OFF LAKE MICHIGAN AS WELL. 500 MILLIBAR SHORTWAVE
LOOKS FAIRLY IMPRESSIVE AS IT RIDES IN OUT OF THE NORTHWEST.
BUFKIT SOUNDINGS FROM THE NAM AND GFS DO SHOW A LIMITED AMOUNT OF
TALL SKINNY CAPE WITH BOTH MODELS SHOWING QPF IN THE WESTERN
CWA...HOWEVER 60 DEGREE DEW POINTS DO LOOK OUT OF PLACE IN THIS
PATTERN GIVEN THE INFLUX OF DRY AIR ON NORTHEAST WINDS. MOS
GUIDANCE LOOKS A BIT BETTER...WHICH WOULD LIMIT THE CAPE EVEN
FURTHER. ANY Q-VECTOR CONVERGENCE...EITHER IN THE LOW OR MID
LEVELS IS MAXIMIZED IN THE MORNING. 500 MILLIBAR WAVE APPEARS TO
HAVE THE GREATEST CONTRIBUTION TO LIFT IN THE MORNING THROUGH
EARLY AFTERNOON...WITH MORE IN THE WAY OF NVA WORKING IN FOR THE
AFTERNOON. NAM AND GFS WANT TO KEEP PRECIP AROUND ALL DAY IN THE
WESTERN CWA. 12Z ECMWF STILL SHOWS PRECIP STAYING WEST OF THE CWA
AND THIS MODEL HAS DEW POINTS BETTER CONFORMING TO THE DRIER LOOK
FOR THE NAM MOS. WILL GO WITH A SMALL POP IN THE WEST FOR NOW
THOUGH THE EAST LOOKS TOO DRY AND STABLE WITH ALL MODELS IN BETTER
AGREEMENT ON THE DRY LOOK THERE.

WEDNESDAY - CONFIDENCE...MEDIUM
HIGH PRESSURE SHIFTS EAST. NOTHING TO GET EXCITED IN THE 500
MILLIBAR PROGS WITH A QUIET NW FLOW PATTERN. BUFKIT SOUNDINGS DO
SHOW LIMITED CAPE TO 650 MILLIBARS BEFORE INVERSION TAKES HOLD.
OVERALL DRY AND STABLE LOOK TO THE PROFILE. WILL KEEP FORECAST DRY.

THURSDAY - CONFIDENCE...MEDIUM
00Z GFS HAS BACKED OFF FROM A WET LOOKING 18Z RUN. BEST LOW LEVEL
JET ACTION STILL LOOKS TO AFFECT AREAS WEST AND NORTH OF SRN WI.
925 MILLIBAR TEMPS RISE INTO THE LOW 20S CELSIUS.

FRIDAY - CONFIDENCE...LOW TO MEDIUM
MODELS CONTINUE TO FOCUS PRECIP WEST AND NORTH OF HERE WITH 850 JET
AXIS DRIVING BULK OF CONVECTION. 500 MILLIBAR HEIGHTS RISE TO
588-591DM WITH 925 TEMPS NUDGING A BIT FURTHER INTO THE 20S
CELSIUS. WOULD LIKE TO TAKE A SWING AT DRY THIS PERIOD GIVEN
CONSENSUS OF MODELS BUT WILL BLEND WITH NEIGHBORS VIA SMALL POPS IN
WESTERN AND NORTHERN CWA.

FRIDAY NIGHT AND BEYOND - CONFIDENCE...MEDIUM
BARRING A MAJOR SHIFT IN BOTH OF THE LONG RANGE MODELS THIS IS
SETTING UP BE TO BE A WET AND UNSETTLED PERIOD AS SHORTWAVES
INTERACT WITH A MOIST AND UNSTABLE ATMOSPHERE. TIMING OF THE
INDIVIDUAL RIDGE RIDERS TOUGH AT THIS RANGE BUT LOW LEVEL JET
BECOMES A PLAYER AS DOES VORTICITY MAXIMA TRAVERSING THE NORTHERN
PERIPHERY OF THE HOT AIR DOME IN THE MID MISSISSIPPI VALLEY.

AVIATION/12Z TAFS/...VFR CONDITIONS UNTIL SHOWERS AND STORMS ARRIVE
WITH MVFR CIGS/ VSBYS LATER THIS AFTERNOON/EVENING. NAM INDICATING
SOME MVFR CIGS AT EASTERN TAF SITES WITH NORTHEAST WINDS OFF THE
LAKE BEHIND COLD FRONT. WILL LEAVE VFR FOR NOW...BUT WILL HAVE TO
BE WATCHED.

MARINE...NO SMALL CRAFT ADVISORY ANTICIPATED AS NORTH TO
NORTHEAST WIND GUSTS BEHIND COLD FRONT PASSING NORTH TO SOUTH
THROUGH REGION LATE THIS AFTERNOON/EVENING WILL REMAIN BELOW CRITERIA.
SOME GUSTS TO 20 KNOTS ARE EXPECTED.

&&

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

$$

UPDATE...MRC
TODAY/TONIGHT AND AVIATION/MARINE...REM
TUESDAY THROUGH SUNDAY...COLLAR