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000
FXUS63 KMKX 301747 AAA
AFDMKX

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
1247 PM CDT WED JUL 30 2014

.UPDATE...

SCATTERED TO BROKEN CUMULUS WILL LINGER THIS AFTERNOON AND EARLY
THIS EVENING ACROSS THE AREA. MAIN 500 MB VORTICITY MAXIMUM WILL
PASS NORTHEAST OF THE AREA DURING THIS TIME. THERE IS A NORTHWEST
TO SOUTHEAST ORIENTED SURFACE TROUGH/WEAK COLD FRONT ACROSS THE
AREA. AREA FORECAST SOUNDINGS WERE SHOWING A FEW HUNDRED J/KG OF
MEAN LAYER CAPE DEVELOPING...WITH STEEP LOW LEVEL LAPSE RATES.

SHOULD SEE SCATTERED SHOWERS DEVELOP BY MID AFTERNOON AND LINGER
UNTIL EARLY THIS EVENING...ESPECIALLY NEAR THE SURFACE BOUNDARY.
AN ISOLATED THUNDERSTORM IS POSSIBLE...THOUGH SOUNDINGS ARE NOT
SUPPORTING MUCH CONVECTION WITH EQUILIBRIUM LEVELS LOW. HIGHS
SHOULD STILL REACH THE UPPER 70S TO AROUND 80 INLAND...WITH
ONSHORE WINDS KEEPING LAKESHORE AREAS IN THE 60S TO AROUND 70.

&&

.AVIATION/18Z TAFS/...

SCATTERED TO BROKEN CUMULUS CLOUDS WILL LINGER INTO EARLY THIS
EVENING ACROSS TAF SITES. SCATTERED SHOWERS SHOULD DEVELOP BY MID
AFTERNOON AND REMAIN UNTIL EARLY EVENING. WILL USE VICINITY
SHOWER WORDING IN TAFS FOR NOW DURING THIS TIME. ISOLATED
THUNDERSTORM IS POSSIBLE BUT WILL NOT MENTION IN TAFS. LIGHT NORTH
WINDS ARE EXPECTED AT MADISON...WITH LIGHT TO MODERATE NORTHEAST
WINDS AT THE EASTERN SITES.

LIGHT WINDS AND MOSTLY CLEAR SKIES ARE EXPECTED LATER THIS EVENING
INTO EARLY THURSDAY MORNING. MORE SCATTERED TO BROKEN CUMULUS WILL
DEVELOP BY MIDDAY THURSDAY...LINGERING INTO EARLY THURSDAY
EVENING. SCATTERED SHOWERS WITH A FEW THUNDERSTORMS ARE POSSIBLE
IN THE AFTERNOON. LIGHT TO MODERATE WEST SOUTHWEST WINDS WILL
PREVAIL THURSDAY.

&&

.PREV DISCUSSION... /ISSUED 330 AM CDT WED JUL 30 2014/

TODAY AND TONIGHT...FORECAST CONFIDENCE - MEDIUM.

BOUNDARY LAYER MIXING CONTRIBUTING TO PREVENTING FOG EARLY THIS
MORNING...AND WEBCAMS NOT SHOWING ANY FOG. HOWEVER WEAKNESS
ASSOCIATED WITH PASSING WEAK FRONT AND SMALL DEWPOINT DEPRESSIONS
MAY YET ALLOW PATCHY FOG TO DEVELOP FOR SEVERAL HOURS.  LIGHT FOG
DEVELOPING UPSTREAM OVER WEST CENTRAL WI...BUT FOR NOW WL HOLD OFF
ON INCLUDING FOG IN EARLY MORNING FORECAST EXCEPT IN WI RVR VLY.

OTRW WEAK MID-LEVEL SHORT WAVE WL BE EXITING SE WI EARLY THIS MRNG.
STILL A SLIGHT CHANCE THIS FEATURE MAY TRIGGER AN ISOLD -SHRA NEXT
HOUR OR TWO.  REST OF MRNG EXPECTED TO BE DRY WHILE ATMOSPHERE
GRADUALLY DESTABILIZES FOR THE AFTN.  WITH AFTN DEWPTS REMAINING IN
THE LOW TO MID 50S...EXPECT MUCAPE VALUES TO REACH VALUES OF 200-400
J/KG.  HOWEVER DO NOT EXPECT AS NUMEROUS CONVECTION AS WHAT OCCURRED
LATER TUE.  SYNOPTIC FORCING EXPECTED TO REMAIN MOSTLY EAST OF SRN
WI AS NEXT SHORT WAVE ROTATING AROUND HUDSON BAY LOW REMAINS OVER
THE CENTRAL GTLAKES.  LEFT EXIT REGION OF UPPER JETLET ALSO REMAINS
FARTHER EAST.  HOWEVER CAN NOT IGNORE WEAK INSTABILITY AND
PERSISTENT CYCLONIC FLOW.  WL CONTINUE LOW POPS FOR -SHRA AND ISOLD
T THIS AFTN INTO THE EVE.  OTHERWISE ANOTHER PARTLY TO MOSTLY SUNNY
DAY IS EXPECTED WITH DAYTIME TEMPS GETTING CLOSE TO SEASONAL NORMAL
WELL AWAY FROM THE ONSHORE FLOW FROM LAKE MICHIGAN.

BOUNDARY LAYER WINDS AND SHALLOW MOISTURE SHOULD PREVENT SIGNIFICANT
FOG ONCE AGAIN TONIGHT AS DEW FORMATION SHOULD PREVAIL.

THURSDAY - CONFIDENCE...MEDIUM
SEE NO REASON TO NOT CONTINUE WITH THE ISOLD/SCT SHRA/TSRA
DEVELOPMENT AS THE OVERALL PATTERN REMAINS UNCHANGED. BROAD
CYCLONIC 500 MILLIBAR FLOW FEATURES AN ELONGATED SHEAR ZONE ACROSS
ERN WI DURG THE MRNG WITH A MORE POTENT WAVE SHIFTING FROM THE
DAKOTAS TO IOWA IN THE AFTERNOON. SOME OF THE DCVA FROM THIS
LATTER FEATURE AFFECTS THE WRN CWA AFTER 21Z OR SO. WITH WEAK
SURFACE TROUGHING AND THE COLDER TEMPS ALOFT WITH DAYTIME
INSTABILITY...WILL CONTINUE THE SHRA/ISOLD TSRA IDEA. 925 TEMPS DO
NUDGE UP A BIT TO THE 19-21C RANGE.

FRIDAY - CONFIDENCE...MEDIUM
PARADE OF SHORTWAVE ENERGY CONTINUES WITH MORE RIPPLES SWINGING
THROUGH IN THE BROAD 500 MILLIBAR CYCLONIC FLOW. THE MAIN
SHORTWAVE WILL ARRIVE FRIDAY NIGHT THOUGH INSTABILITY AND
DIURNALLY DRIVEN CONVECTION WILL LIKELY DEVELOP BEFORE THE HELP
FROM UPSTAIRS. WILL KEEP SHRA CHANCES GOING ALL NIGHT DUE TO THE
PASSAGE OF THE MAIN VORT AFTER THE PEAK INSTABILITY.

SATURDAY - CONFIDENCE...MEDIUM
POSITIVELY TILTED UPPER TROUGH WILL BE NEAR SE WI AT 12Z WITH A
SLOW SHIFT TO THE EAST. LINGERING VORTICITY AND COLD POOL ALOFT
SUGGESTS KEEPING THE CHANCE OF SHRA/ISOLD TSRA IN THE GRIDS.

SUNDAY - CONFIDENCE...MEDIUM
UPPER TROUGH CONTINUES TO SHIFT EAST WITH MODELS SHOWING MORE OF
AN ANTICYCLONIC LOOK TO THE UPPER PATTERN FOR A CHANGE. THE GFS
LOOKS TOO AGGRESSIVE WITH PRECIP RETURN AND PREFER THE LOOK OF THE
ECMWF KEEPING BEST CHC TO OUR NORTH AND NORTHWEST NEAR SURFACE
TROUGH.

MONDAY AND TUESDAY - CONFIDENCE...MEDIUM
FRONTAL BOUNDARY IS PROGGD TO SAG INTO THE AREA AND WILL
POTENTIALLY SERVE AS A FOCUS FOR SHRA/TSRA. LOW LEVEL JET DOES NOT
LOOK STRONG NOR DOES THE UPPER FLOW DURING THIS PERIOD. HOWEVER
850/925 BAROCLINICITY MAY BE THE BIGGER DRIVING FORCE FOR
CONVECTION UNTIL BETTER UPPER SUPPORT ARRIVES BEYOND THIS PERIOD.

AVIATION/12Z TAFS/...A PERIOD OF FOG MAY YET AFFECT KENW AND KUES
DUE TO LIGHT SFC WINDS AND LOW DEWPOINT DEPRESSIONS.  HOWEVER EXPECT
FOG TO REMAIN LIGHT AND BRIEF DUE TO BOUNDARY LAYER MIXING AND
PATCHY CLOUDS.  VFR CONDITIONS EXPECTED FOR THE BULK OF THE PERIOD.
CHANCE FOR CONVECTION RETURNS THIS AFTN AND EVE HOWEVER SHOULD BE
MORE ISOLD COMPARED TO TUE AFTN/EVE.

MARINE...WEAK SFC FRONT LOCATED BETWEEN KMTW AND KSBM WILL SAG SWD
ACROSS SRN LAKE MI THRU EARLY THIS MRNG.  SFC WNDS WL TURN FROM THE
W TO THE N TO NE DURING THE MRNG AS THE FRONT PASSES.  WIND SPEEDS
WL REMAIN LIGHT...LESS THAN 15 KTS.

&&

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

$$

UPDATE...WOOD
TODAY/TONIGHT AND AVIATION/MARINE...MBK
THURSDAY THROUGH TUESDAY...COLLAR