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000
FXUS63 KMKX 122028
AFDMKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
328 PM CDT SUN MAY 12 2013

.SHORT TERM...

TONIGHT...FORECAST CONFIDENCE MEDIUM

LINGERING CU FIELD IN EASTERN CWA TO CLEAR OUT WITH LOSS OF
HEATING AND LESS INFLUENCE OF THE UPPER TROUGH. NOTICING SOME
RETROGRESSION OF THE SURFACE RIDGE AXIS IN THE PLAINS. HOWEVER
GRADIENT ACROSS THE CWA DOES APPEAR TO BE SLACKENING A BIT AND DO
EXPECT WINDS TO EASE AS THE NIGHT WEARS ON. SOME CONCERN PROLONGED
MIXING COULD SLOW THE TEMP DROPOFF. STILL PONDERED AN EXPANSION OF
THE FREEZE WARNING A BIT MORE WITH DEW POINTS IN THE LOW TO MID
20S AND THE CHILLY DAYTIME TEMPS. FOR NOW WILL LEAVE CURRENT
FROST/FREEZE HEADLINES AS IS WITH THE VAST MAJORITY OF GUIDANCE
NOT SUPPORTING AN EXPANSION.

MONDAY...FORECAST CONFIDENCE MEDIUM

AFTER THE CHILLY/FROSTY START...ATTENTION TURNS TO FORCING
DEVELOPING WITH 700 MILLIBAR BAROCLINIC RIBBON. MOISTURE INCREASES
DURING THE AFTERNOON AND WILL BRING SOME HIGHER END CHANCE POPS
INTO PARTS OF OUR WEST LATER IN THE AFTERNOON. SOME CONCERN THAT
THE LOW LEVELS WILL BE TOO DRY BUT THE FORCING IS DECENT WITH THE
700 WAA.

MONDAY NIGHT THROUGH THURSDAY...FORECAST CONFIDENCE MEDIUM TO HIGH

FAIRLY STRONG MID LEVEL WARM ADVECTION AND FRONTOGENESIS WILL BE
MOVING EAST ACROSS SRN WI MON EVENING. MORE MODELS ARE SHOWING
SLIGHTLY MORE MID LEVEL MOISTURE WITH THIS SYSTEM AND FCST
SOUNDINGS STILL SATURATING DOWN TO ABOUT 800-850 MB. MODELS
TYPICALLY ARE TOO DRY IN THIS SCENARIO DUE TO DRY AIR IN THE LOW
LEVELS. WENT WITH LIKELY POPS WITH RAINFALL AMOUNTS UNDER 0.10
INCHES FOR MON EVENING.

STRONG SFC-850 MB WARM ADVECTION WILL THEN PREVAIL THROUGH TUE AS
STRONG CYCLOGENESIS ENSUES FROM THE NRN PLAINS INTO WRN ONTARIO
CANADA VIA A 100 KT JET STREAK AND STRONG SHORTWAVE TROUGH. THIS
WILL FLATTEN THE HIGH AMPLITUDE RIDGE WITH THE SHORTWAVE RIDGE TO
COME OVER SRN WI ON TUE. THE ECMWF 925 MB TEMPS IS A COMPROMISE
BETWEEN THE HOT NAM AND COOLER GFS AND YIELDS HIGH TEMPS IN THE
LOWER TO MID 80S WELL AWAY FROM THE COOLING OF THE LAKE BREEZE.
WITH THE UPPER DYNAMICS WELL TO THE NORTH...A STRONG CAP WILL BE IN
PLACE AS THE COLD FRONT APPROACHES TUE EVENING WITH MODEL 2M DEWPOINTS
10-15 DEGREES TO HIGH AND TEMPS NEARLY 10C AT 700 MB. THUS WILL
FORECAST A DRY COOL FROPA FOR TUE NT AND WED AM.

A WEAK W-E AREA OF HIGH PRESSURE WILL THEN SETTLE OVER THE
CENTRAL PLAINS TO THE LOWER GREAT LAKES FOR WED INTO THU...WITH
THE COLD FRONT SLOWLY MOVING SOUTH THROUGH IL. WARM...SUMMER LIKE
TEMPS WILL CONTINUE AS THE JET STREAM REMAINS ZONAL OVER THE NRN
USA WITH 1000-500 MB THICKNESSES AROUND 564 DM.


.LONG TERM...

THURSDAY NIGHT THROUGH SUNDAY...FORECAST CONFIDENCE MEDIUM

EXTENDED MODELS TAKE AN UPPER TROUGH INTO THE WRN USA FOR THU-FRI
WITH IT REACHING THE PLAINS FOR THE WEEKEND...AND POSSIBLY THE
GREAT LAKES BY THE END OF THE WEEKEND. LEE SIDE CYCLOGENESIS WILL
ENSUE AROUND FRI WITH THE SFC LOW AND UPPER WAVE REACHING WI
EITHER SUN OR MON. LIKELY POPS FOR THUNDER IS FORECAST SAT NT AND
SUN WITH ONLY SMALL POPS OF THUNDER FROM THU NT INTO FRI NT AS THE
STALLED FRONT TO THE SOUTH WILL SLOWLY LIFT NORTH TOWARD WI. GIVEN
THE SLOW MOVEMENT OF THE WEEKEND SYSTEM...THERE IS EXPECTED TO
SUFFICIENT LOW LEVEL MOISTURE IN PLACE FOR DEEP CONVECTION ONCE IT
ARRIVES.


&&

.AVIATION/00Z TAFS/...SCT-BKN VFR CU FIELD IN ERN WI WILL CONTINUE
TO DISSIPATE INTO THE EVENING HOURS. PLENTY OF CLEAR AIR UPSTREAM SO
THAT WILL TAKE HOLD THROUGH MONDAY MORNING. WINDS DIMINISH AS WELL
WITH SURFACE RIDGE AXIS DRAWING CLOSER. MID DECK WILL INCREASE
MONDAY AFTERNOON WITH 700 MILLIBAR WARM ADVECTION. BEST POTENTIAL
FOR SHRA WILL BE IN SC WI LATER IN THE AFTERNOON.


&&

.MKX WATCHES/WARNINGS/ADVISORIES...
WI...FROST ADVISORY FROM 1 AM TO 7 AM CDT MONDAY FOR WIZ051-052-
     057>060-062>072.

     FREEZE WARNING FROM 1 AM TO 7 AM CDT MONDAY FOR WIZ046-047-056.

LM...NONE.

&&

$$

TONIGHT/MONDAY AND AVIATION/MARINE...COLLAR
MONDAY NIGHT THROUGH SUNDAY...GEHRING