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000
FXUS63 KMKX 111636 AAA
AFDMKX

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
1136 AM CDT TUE JUN 11 2013

.UPDATE...
MAIN CONCERN IN THE TODAY PERIOD WERE TEMPERATURES. OTHERWISE...THE
FOG THIS MORNING QUICKLY DISSIPATED ACROSS THE NEARSHORE AREAS AND
IN THE WISCONSIN RIVER VALLEY. CURRENTLY...VIS SAT SHOWS DIURNAL
CU ALREADY OVER A LARGE PORTION OF THE CWA WITH BASES AROUND 3000
TO 4000 FT.

TEMPS WERE RAISED AROUND TWO DEGREES IN THE NORTHERN HALF TO
THREE TO FIVE DEGREES IN THE SOUTHERN HALF. MILWAUKEE AT 10 AM HAD
ALREADY REACHED 76 DEGREES. THUS...THE LAKE SHORE AREAS ARE GOING
TO HAVE GREATER HIGHS THAN PREVIOUSLY EXPECTED. ITS ANTICIPATED
THAT THE LAKE SHORE AREAS WILL REACH INTO THE LOW 80S BEFORE THE
LAKE BREEZE/ONSHORE FLOW COOLS THEM DOWN. CURRENT THINKING IS THAT
THE LAKE BREEZE WILL START MOVING IN AT AROUND 18-19 UTC/1-2 PM.
ALTHOUGH THERE WILL BE SCT-BKN SKIES WITH ADEQUATE INSOLATION
...LOW-LEVEL WAA...WARM 925 HPA TEMPS AT 21-22 C...AND SUFFICIENT
MIXING...HIGHS SHOULD BE ABLE TO REACH INTO THE MID 80S AWAY FROM
THE LAKE.

&&

.AVIATION/18Z TAFS/...
VFR CONDITIONS ARE EXPECTED FOR THE REST OF THE DAY. THOUGH A
CONCERN IS DIURNAL CU MAY HAVE BASES RIGHT ON THE CIG THRESHOLD
BETWEEN MVFR AND VFR. GIVEN THE SKY COVERAGE...FLIGHT RULES MAY
FLUCTUATE BETWEEN MVFR AND VFR. ELSE...WINDS WILL BE LIGHT TODAY.
THE LAKE BREEZE IS EXPECTED TO BEGIN MOVING IN AROUND 1 PM IN KMKE
THEN KENW WITH LIGHT SOUTHEAST WINDS.

ELSE...POTENTIAL FOR MVFR/IFR VISIBILITIES EXIST WITH LIGHT FOG
AT TAF SITES AFTER 06Z WEDNESDAY. LIGHT WINDS AND A MOIST AIR MASS
WILL BE IN PLACE. OTHERWISE A CONCERN LATE TONIGHT IS A COMPLEX OF
THUNDERSTORMS THAT MAY CLIP MADISON AFTER 06Z WEDNESDAY. THOUGH
LATEST GUIDANCE IS PUSHING THIS THREAT TO OCCUR LATER IN
TIME. STAYED WITH VICINITY THUNDER DUE TO UNCERTAINTY WITH TIMING
AND TRACK OF THESE STORMS.

&&

.MARINE...
DENSE FOG ADVISORY WAS CANCELLED THIS MORNING AS FOG DISSIPATED
OVER THE NEARSHORE WATERS WITH DAYTIME HEATING. REMOVED MENTION OF
PATCHY FOG FOR THE REST OF THE DAY...THOUGH MORE FOG IS POSSIBLE
TONIGHT GIVEN THE LIGHT WINDS AND THE MOIST AIR MASS THAT WILL BE
IN PLACE OVER THE COOL WATERS. IN ADDITION...DENSE FOG MAY BE
POSSIBLE AGAIN.

BREEZY NORTH WINDS ON WEDNESDAY NIGHT MAY BRING WAVES THAT
APPROACH SMALL CRAFT ADVISORY LEVELS...WITH WAVES UNDER FOUR FEET.

&&

.PREV DISCUSSION... /ISSUED 356 AM CDT TUE JUN 11 2013/

SHORT TERM...

TODAY AND TONIGHT...FORECAST CONFIDENCE IS MEDIUM.

PATCHY TO AREAS OF FOG WERE OBSERVED IN THE EASTERN PORTIONS OF THE
FORECAST AREA...ALONG WITH THE WISCONSIN RIVER VALLEY LOCATIONS.
THIS WAS DUE TO LIGHT/CALM WINDS AND SMALL TEMPERATURE/DEW POINT
SPREADS ACROSS THE AREA. WILL CONTINUE TO MENTION PATCHY/AREAS OF
FOG INTO MID MORNING ACROSS THE AREA...UNTIL WINDS PICK UP WITH
DAYTIME HEATING. NOT ANTICIPATING ANY WIDESPREAD DENSE FOG...PERHAPS
LOCALIZED IN THE WISCONSIN RIVER VALLEY AND NEAR LAKE MICHIGAN.

WARM DAY IS EXPECTED TODAY...WITH WARM AIR ADVECTION BRINGING 925MB
TEMPERATURES UP ENOUGH FOR HIGHS TO REACH THE LOWER TO MID 80S
ACROSS MOST OF THE AREA. LOCATIONS NEAR LAKE MICHIGAN WILL SEE A
LAKE BREEZE DEVELOP BY MIDDAY AND PUSH INLAND A BIT DURING THE
AFTERNOON...KEEPING TEMPERATURES THERE COOLER.

MAIN ISSUE WILL BE CONVECTION POTENTIAL TONIGHT AND ANY SEVERE
POTENTIAL WITH IT. KEEPING THE FORECAST DRY FOR TODAY...AS THE AREA
WILL BE CAPPED PER AREA FORECAST SOUNDINGS FROM NAM/GFS/RAP MODELS.
MOISTURE WILL ALSO BE LACKING IN THE LOW LEVELS...DESPITE DEW POINTS
REMAINING IN THE LOWER TO MID 60S. 850MB LOW LEVEL JET NOSE WILL
REMAIN FAR ENOUGH TO THE SOUTHWEST TO KEEP ANY CHANCES FOR
CONVECTION THERE.

THE 850MB LOW LEVEL JET REMAINS POINTING INTO CENTRAL IOWA INTO
NORTHERN ILLINOIS TONIGHT PER GFS/CANADIAN/ECMWF MODELS. THIS IS
WHERE THE FOCUSED 850MB WARM AIR ADVECTION IS LOCATED. THE NAM
CONTINUES TO PUSH THE NOSE OF THE LOW LEVEL JET AND FOCUSED WARM AIR
ADVECTION INTO SOUTHWEST WISCONSIN THIS EVENING...THEN FOCUSING TO
THE SOUTH AND EAST LATER TONIGHT. NAM MAY BE OVERDONE WITH ITS
NORTHWARD BIAS VERSUS THE OTHER MODELS.

AREA FORECAST SOUNDINGS FROM NAM/GFS DO SHOW ELEVATED CAPE AND
EFFECTIVE LAYER SHEAR VALUES INCREASING DURING THE NIGHT TO SUPPORT
A RISK OF SEVERE HAIL. SPC HAS MAINLY THE SOUTHWEST HALF OF THE
FORECAST AREA IN SLIGHT RISK FOR SEVERE STORMS...MAINLY FOR POSSIBLE
MCS MOVING INTO THE AREA LATER TONIGHT FROM NORTHERN IOWA AND
SOUTHERN MINNESOTA. CIPS ANALOGS SUPPORT SEVERE RISK...THOUGH SPC
SSEO UPDRAFT HELICITY/10 METER WIND PROBABILITY PRODUCTS FAVOR THE
SEVERE RISK WELL WEST OF THE AREA. THERE IS SOME UNCERTAINTY WITH
THE POSSIBLE MCS TRACK...AND IT MAY STAY JUST SOUTHWEST OF THE AREA.
FOR NOW...WILL CONTINUE TO BRING INCREASING POPS INTO THE AREA
TONIGHT...HIGHEST WEST OF MADISON LATER TONIGHT.

WEDNESDAY AND WEDNESDAY NIGHT...FORECAST CONFIDENCE MEDIUM.

SOUTHERN WISCONSIN WILL CONTINUE TO BE ON THE NORTHERN PERIPHERY OF
CONVECTIVE ACTIVITY. ONGOING OVERNIGHT STORMS WILL BE WINDING DOWN
THE FIRST HALF OF WEDNESDAY MORNING...THEN THERE WILL BE A RELOAD
PERIOD WITH PROBABLY QUIET WEATHER MIDDAY. MODEL SOUNDINGS MAINTAIN
A DRY PROFILE IN THE LOWEST 10KFT THROUGH EARLY AFTERNOON AND THEN
BECOME MORE MOIST AFTER THAT.

THE 850MB WARM FRONT WILL BE LIFTING INTO SOUTHERN WI ON WEDNESDAY
JUST AHEAD OF A STRONGER SHORTWAVE TROUGH. THIS WILL RESULT IN AT
LEAST THE SOUTH HALF OF THE FORECAST AREA TO TAP INTO THE VERY MOIST
AND UNSTABLE AIR FOR A SHORT TIME IN THE FAVORABLE AFTERNOON TIME
PERIOD. SPC HAS NEARLY ALL OF THE MKX FORECAST AREA IN A SLIGHT RISK
FOR SEVERE WEATHER WITH A HATCHED AREA FOR A RISK OF SIGNIFICANT
SEVERE.

THE IDEA IS THAT ISOLATED THUNDERSTORMS COULD DEVELOP ALONG THE WARM
FRONT IN IOWA OR IL AND THEN CLUSTERS OF STORMS WOULD FORM CLOSE TO
THE SHORTWAVE TROUGH BACK IN EASTERN IOWA AND SOUTHWEST WI AND
EVOLVE INTO BOWING LINE SEGMENTS THAT WOULD SHIFT QUICKLY
EAST-SOUTHEASTWARD BY EVENING. DAMAGING WIND WILL BE THE MAIN THREAT
IF THESE STORMS MOVE ACROSS SOUTHERN WI IN THE LATE AFTERNOON/EARLY
EVENING. ELEVATED CAPE AROUND 1000 J/KG SUPPORTS SOME MARGINALLY
SEVERE HAIL AS WELL. WITH PRECIPITABLE WATER VALUES INCREASING
TO 1.75 INCHES OR GREATER...EXPECT HEAVY RAIN TO ACCOMPANY THESE
STORMS.

THURSDAY THROUGH FRIDAY...FORECAST CONFIDENCE HIGH.

A HIGH PRESSURE RIDGE WILL BE MOVING ACROSS THE UPPER MIDWEST AND
GREAT LAKES REGION DURING THIS PERIOD. EXPECT SUNSHINE...LOWER
DEWPOINTS AND LIGHT NORTH TO EAST WINDS. HIGHS WILL BE AROUND
CLIMATOLOGICAL NORMAL INLAND FROM THE LAKE IN THE MID/UPPER 70S.

LONG TERM...

FRIDAY NIGHT THROUGH WEDNESDAY...FORECAST CONFIDENCE LOW.

THE NEXT CHANCE FOR SHOWERS AND STORMS WILL SPREAD INTO SOUTHERN WI
FRI NIGHT/SAT AS THE UPPER RIDGE BREAKS DOWN AND TRANSITIONS TO
ZONAL FLOW AND A SHORTWAVE MOVES ACROSS THE IA/WI/IL AREA.

SUNDAY MAY END UP DRY WITH WEAK HIGH PRESSURE OVERHEAD. CLOUDS OVER
THE AREA WILL KEEP TEMPS IN CHECK THOUGH. PRECIP CHANCES FOR MONDAY
THROUGH WEDNESDAY ARE DEBATABLE DUE TO MODEL PATTERN DIFFERENCES.

AVIATION/12Z TAFS/...FOG WILL KEEP VISIBILITIES RANGING BETWEEN
AIRPORT MINIMUMS AND ALTERNATE MINIMUMS UNTIL AROUND 15Z AT THE
EASTERN TAF SITES...ESPECIALLY KENOSHA AND MILWAUKEE. VISIBILITIES
DOWN TO AROUND ALTERNATE MINIMUMS ARE POSSIBLE AT MADISON DURING
THIS TIME. ANY LOW STRATUS THAT DEVELOPS SHOULD BE SHORT LIVED.

VFR CONDITIONS SHOULD THEN RETURN FOR THE REST OF THE DAY. LIGHT
WINDS WILL BECOME SOUTHWEST AT MADISON AND WAUKESHA. LAKE BREEZE
SHOULD BRING LIGHT SOUTHEAST WINDS TO MILWAUKEE AND KENOSHA BY
18Z...LINGERING UNTIL AROUND 01Z WEDNESDAY.

MAY SEE MVFR/IFR VISIBILITIES WITH LIGHT FOG AT TAF SITES AFTER 06Z
WEDNESDAY...AS WINDS BECOME LIGHT WITH LOW LEVEL MOISTURE LINGERING.
COMPLEX OF THUNDERSTORMS MAY CLIP MADISON AS WELL AFTER 06Z
WEDNESDAY...BUT WENT JUST VICINITY THUNDER FOR NOW DUE TO SOME
UNCERTAINTY WITH THE TRACK OF THESE STORMS.

MARINE...DENSE FOG ADVISORY WILL CONTINUE OVER THE NEARSHORE WATERS
UNTIL 14Z TODAY...WITH LIGHT WINDS AND MOIST AIRMASS OVER THE COOL
LAKE WATERS. THE FOG SHOULD STEADILY IMPROVE THROUGH THE REST OF THE
DAY. MORE FOG IS POSSIBLE TONIGHT...AS WINDS BECOME LIGHT AGAIN WITH
THE MOIST AIRMASS LINGERING OVER THE COOL WATERS. DENSE FOG MAY BE
POSSIBLE AGAIN.

BREEZY NORTH WINDS WEDNESDAY NIGHT MAY BRING WAVES CLOSE TO SMALL
CRAFT ADVISORY LEVELS.

&&

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

$$

UPDATE...ET/MEB
TODAY/TONIGHT AND AVIATION/MARINE...WOOD
WEDNESDAY THROUGH MONDAY...MRC