Area Forecast Discussion
Issued by NWS Milwaukee/Sullivan, WI

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FXUS63 KMKX 091754 AAA
AFDMKX

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
1254 PM CDT WED APR 9 2014

.UPDATE...SOUTHWEST WINDS SHOULD CONTINUE TO INCREASE DURING THE
AFTERNOON...AS PRESSURE GRADIENT SLOWLY TIGHTENS. SHOULD SEE GUSTS
IN THE 18 TO 22 KNOT RANGE BY LATER THIS AFTERNOON. THIS SHOULD
PUSH THE LAKE BREEZE BACK EASTWARD TO ALONG THE SHORE.

THE MIXING COMBINED WITH EXPECTED 925 MB TEMPERATURES SHOULD
BRING HIGHS INTO THE MID 60S ACROSS MOST OF THE AREA. MAY SEE A
FEW WARMER SPOTS IN THE WESTERN COUNTIES. MAINLY SOUTH WINDS OVER
THE LAKE SHOULD KEEP LAKESHORE AREAS NORTH OF PORT WASHINGTON IN
THE UPPER 40S TO LOWER 50S.

&&

.AVIATION/18Z TAFS/...GUSTY SOUTHWEST WINDS ARE EXPECTED THIS
AFTERNOON...WITH SUSTAINED SOUTHWEST WINDS INTO MOST OF TONIGHT IN
THE 13 TO 14 KNOT RANGE. LOW LEVEL WIND SHEAR CONDITIONS ARE
EXPECTED TONIGHT INTO EARLY THURSDAY MORNING. SOUTHWEST WINDS IN
THE 40 TO 45 KNOT RANGE ARE EXPECTED AT THE 1500 TO 2000 FOOT
ABOVE GROUND LEVEL AREA TONIGHT INTO EARLY THURSDAY MORNING.

MID LEVEL CLOUDS WILL MOVE INTO TAF SITES LATER
TONIGHT...LINGERING THROUGH THURSDAY MORNING. COLD FRONT WILL
BRING RAIN SHOWERS THURSDAY MORNING...ENDING BY EARLY AFTERNOON
FROM WEST TO EAST. VFR CONDITIONS ARE EXPECTED.

WINDS WILL VEER WEST TO NORTHWEST BEHIND A COLD FRONTAL PASSAGE
BY THURSDAY AFTERNOON...GUSTING TO 20 KNOTS AT TIMES.

&&

.MARINE...A SMALL CRAFT ADVISORY IS IN EFFECT FROM 21Z THIS
AFTERNOON UNTIL 14Z THURSDAY ACROSS THE NEARSHORE WATERS OF LAKE
MICHIGAN. A TIGHT PRESSURE GRADIENT BY LATER THIS AFTERNOON AND
INTO THURSDAY MORNING WILL ALLOW FOR GUSTY SOUTH WINDS THIS
AFTERNOON...BECOMING SOUTHWEST TONIGHT INTO THURSDAY MORNING. THE
INVERSION ABOVE THE LAKE SURFACE WILL LIMIT MIXING TONIGHT INTO
THURSDAY MORNING.

HOWEVER...GUSTS NEAR THE SHORE SHOULD REACH 22 KNOTS BY LATER
THIS AFTERNOON. GUSTS UP TO 25 KNOTS ARE EXPECTED TONIGHT...AS
STRONG LOW LEVEL WINDS WILL EXIST JUST ABOVE THE SURFACE. DESPITE
THE INVERSION OVER THE WATER...THESE GUSTS SHOULD STILL FREQUENTLY
OCCUR. WAVES SHOULD BUILD TO 3 TO 5 FEET TONIGHT INTO THURSDAY
MORNING...HIGHEST TOWARD THE OPEN WATERS.

WINDS WILL VEER WEST BEHIND A COLD FRONT BY THURSDAY
AFTERNOON...GUSTING TO AROUND 20 KNOTS. WAVES SHOULD SUBSIDE AS
WINDS BECOME OFFSHORE. WINDS WILL THEN SUBSIDE THURSDAY NIGHT.

&&

.FIRE WEATHER...SOUTHWEST WINDS WILL BECOME GUSTY DURING
AFTERNOON HOURS...GUSTING TO 25 MPH AT TIMES. DEW POINTS IN THE
UPPER 20S TO LOWER 30S WILL PRODUCE VERY LOW RELATIVE HUMIDITY
VALUES WILL THAT WILL RANGE FROM 25 TO 30 PERCENT.

HOWEVER...TEMPERATURES WILL ONLY REACH IN THE MID 60S IN MOST
AREAS. THUS...WILL CONTINUE TO HIGHLIGHT THE GUSTY WINDS AND VERY
LOW RELATIVE HUMIDITY VALUES IN THE FIRE WEATHER FORECAST.

VERY LOW RELATIVE HUMIDITY VALUES ARE EXPECTED AGAIN
THURSDAY...ESPECIALLY IN SOUTH CENTRAL WISCONSIN. NORTHWEST WINDS
BEHIND COLD FRONT IN THE AFTERNOON MAY GUST TO 20 TO 25 MPH.
TEMPERATURES WILL REMAIN IN THE UPPER 50S TO LOWER 60S.

&&

.PREV DISCUSSION... /ISSUED 336 AM CDT WED APR 9 2014/

TODAY AND TONIGHT...FORECAST CONFIDENCE IS HIGH.

QUIET WEATHER DAY WITH SHORT WAVE RIDGING BETWEEN DEEP...PHASED
EASTERN U.S. TROUGH AND SHORT WAVE CROSSING THE PRAIRIE PROVINCES OF
CANADA. WARM ADVECTION AHEAD OF CANADIAN WAVE BRINGS 925 MB TEMPS UP
TO +10C TO +11C OVER WRN CWA...AND +9C TO +10C EAST BY 00Z
THURSDAY...WHICH YIELDS MID 60S HIGHS WEST AND AROUND 60 EAST WITH
INCREASING SOUTHWEST WINDS THAT WILL BRING THE 60 DEGREE READINGS
RIGHT UP TO LAKE MICHIGAN.

AFTERNOON FORECAST SOUNDINGS HOLDING A CAP AROUND 800 MB...WITH
MIXING UP TO BETWEEN 870 MB/NAM AND GFS...AND 835 MB/RAP. THIS
ALLOWS TAPPING OF 25 TO 30 KT WINDS...BUT PREVENTS REACHING EVEN
STRONGER WINDS ABOVE.

WINDS ALOFT ARE EVEN STRONGER TONIGHT WITHIN THERMAL RIDGE AHEAD OF
APPROACHING MID-LEVEL TROUGH/SFC COLD FRONT...WITH 40-50 KNOTS DOWN
TO 900 MB. THE RESULTING INVERSION WITH THE THERMAL RIDGE MOVING
OVER TONIGHT AND ENOUGH NOCTURNAL SURFACE COOLING WILL PREVENT
MIXING THE STRONGEST WINDS DOWN TO THE SURFACE...BUT STILL EXPECT
WIND GUSTS OF 25 TO 30 MPH.

00Z NAM AND CANADIAN GEM ALONG WITH WPC KEEP PCPN NORTH OF CWA
THROUGH 12Z THURSDAY...WHILE 00Z RUNS OF GFS AND ECMWF DROP QPF INTO
THE NORTHERN HALF...OR WESTERN HALF OF CWA RESPECTIVELY BETWEEN 06Z
AND 12Z.

THURSDAY - CONFIDENCE...MEDIUM
QUICK HITTING SHRA POTENTIAL DURING THE MORNING. SURFACE/850
FRONTS SWING THROUGH. MID LEVEL SHORTWAVE WILL OFFER CYCLONIC
VORTICITY ADVECTION TO THE FORCING PROCESS. MODELS ARE ALL SHOWING
MORNING QPF WITH THE AFTERNOON DRY. WHILE WARMEST 850 TEMPS ARE
FOUND WITHIN THE WARM PROD EXTENDING INTO SRN WI DURG THE
MORNING...AIRMASS WORKING IN UPSTREAM WILL STILL RESULT IN MILD
CONDITIONS. 925 TEMPS ACTUALLY REBOUND NICELY WITH THE DRY NW FLOW
IN THE WAKE OF THIS FEATURE. SO EXPECTING MANY HIGHS IN THE UPPER
50S/LOW 60S.

FRIDAY - CONFIDENCE...MEDIUM
ANOTHER SHORTWAVE RIDES IN WITH ANOTHER SLUG OF WAA. NAM IS DRY
WHILE THE GFS AND ECMWF ARE SHOWING SOME VRY LGT QPF. SOUNDINGS
LOOK PRETTY DRY THOUGH SOME STEEP LAPSE RATES NOTED. WILL GO WITH
A SMALL CHC FOR AFTN SHRA. 925 TEMPS BACK TO 9-11C SO MORE 60S
LIKELY ON THE WAY. THE 00Z NAM IS SHOWING 14C AND A LITTLE HIGHER
AT 925.

SATURDAY AND SATURDAY NIGHT - CONFIDENCE...MEDIUM
UNSETTLED PERIOD AS UPPER FLOW TURNS SOUTHWEST AND LOW PRESSURE
APPROACHES FROM THE PLAINS. WARM AIR/MOISTURE ADVECTION WILL
LIKELY RESULT IN SHRA DEVELOPMENT DURING THE DAY WITH POTENTIAL
FOR TSRA SAT NGT. SHORTWAVE NOTED IN THE SW UPR FLOW AND
APPROACHING FRONTAL BOUNDARY WILL AID IN VERTICAL MOTION. THERE IS
ALSO A SIGNIFICANT UPPER LEVEL DIVERGENCE SIGNATURE ASSOCIATED
WITH RIGHT REAR QUADRANT OF JET CORE SITUATED TO THE NORTH AND
NORTHEAST OF WI.

SUNDAY AND MONDAY - CONFIDENCE...MEDIUM
00Z ECMWF HAS TRENDED A BIT MORE TOWARDS THE GFS AND GEM SOLUTION
ESPECIALLY HEADING INTO MONDAY...THUS ALLOWING FOR A BOOST TO
MEDIUM CONFIDENCE. STILL SOME UNCERTAINTY IN THE SHORTER RUN AS
THE ECMWF KEEPS RAIN/SOME THUNDER GOING SUNDAY WHILE THE GFS AND
GEM ARE DRY WITH MUCH MORE PROGRESSION. BETTER CONFIDENCE ARRIVES
FOR MONDAY AS SECONDARY LOW TRENDS FASTER CATCHES UP A BIT TO THE
GFS/GEM SOLUTIONS. 00Z ECMWF WILL STILL KEEP THINGS WET AROUND
HERE THROUGH SUNDAY NIGHT...BUT MUCH LESS QPF AVAILABLE WITHIN THE
COLDER AIRMASS. SO SOME CONSENSUS TOWARDS A MORE PROGRESSIVE LOOK
COMING INTO PLAY AS WE HEAD INTO MONDAY. WHILE SOME SNOW IN THE
COLDER AIR IS STILL LOOKING POSSIBLE HAVE TRIMMED DOWN AMOUNTS
CONSIDERABLY GIVEN THE ECMWF TREND TOWARDS A MORE PROGRESSIVE
SOLUTION OF THE OTHER MODELS. A CHILLY NORTHERLY FLOW EXPECTED
MONDAY IN THE WAKE OF THE LOW. 925 TEMPS WILL DROP BELOW ZERO SO
SOME AREAS MAY STRUGGLE TO CLIMB ABOVE 40. A STEADY NORTH WIND
WILL ONLY ADD TO THE BITE.

TUESDAY - CONFIDENCE...LOW
GFS AND ECMWF NOT IN SYNC WITH THE ECMWF SHOWING VORT ACTION
RIDING ACROSS STATE AT THE BASE OF LARGER SCALE POSITIVE TILT
TROUGH AXIS. MEANWHILE THE GFS IS SHOWING A MORE ANTICYCLONIC LOOK
TO THE FLOW PATTERN WITH HIGH PRESSURE IN CONTROL. ALLBLEND POPS
ARE GOING WITH THE DRY LOOK. TEMPS LIKELY TO REMAIN ON THE COOL
SIDE IN THE 40S.

AVIATION/12Z TAFS/...EXPECT VFR CONDITIONS THROUGH THE FORECAST WITH
ANY PCPN HOLDING OFF UNTIL AFTER 12Z THURSDAY. SW WINDS WILL INCREASE
THROUGH THE LATE MORNING AND AFTERNOON...WITH GUSTS TO 20 TO 25 KNOTS
BY MID AFTERNOON. COMBINATION OF NOCTURNAL COOLING AND THERMAL RIDGE
MOVING OVER REGION WILL SET UP AN INVERSION. LOW- LEVEL WIND SHEAR
POTENTIAL AFTER 03Z AS 40KT-45KT WINDS DIP DOWN TO AROUND 1K FT.
SFC WINDS CURRENTLY LOOK TO BE SUFFICIENTLY STRONG TO NOT ADD AT
THIS TIME...BUT IF THEY DECOUPLE MORE THAN CURRENTLY EXPECTED WILL
HAVE TO ADD LLWS.

MARINE...SOUTHWEST WINDS WILL INCREASE THROUGH THE AFTERNOON INTO THE
EVENING WITH 40-45 KT WINDS DIPPING DOWN TO 1K FT. HOWEVER...COLD
WATER WILL SET UP ENOUGH OF AN INVERSION TO PREVENT MIXING THESE
STRONG WINDS DOWN TO THE SURFACE. WIND GUSTS ARE CURRENTLY BORDERLINE
FOR A SMALL CRAFT ADVISORY...AND OFFSHORE FETCH WILL LIMIT WAVE HEIGHTS.
WILL HOLD OFF ISSUING AN ADVISORY AT THIS TIME AFTER COLLABORATION
WITH SURROUNDING OFFICES.

FIRE WEATHER...SOUTHWEST WINDS WILL INCREASE DURING THE LATE
MORNING AND BECOME GUSTY DURING AFTERNOON HOURS...GUSTING TO 25 MPH
AT TIMES. DRY DEW POINTS IN THE UPPER 20S TO LOW 30S WILL PRODUCE
VERY LOW RELATIVE HUMIDITY VALUES WILL THAT WILL RANGE FROM 25 TO 30
PERCENT...WITH THE MAJORITY OF THE AREA UNDER 30 PERCENT.
HOWEVER...TEMPERATURES WILL ONLY REACH IN THE LOWER TO MID 60S.
THUS...WILL CONTINUE TO HIGHLIGHT THE GUSTY WINDS AND VERY LOW
RELATIVE HUMIDITY VALUES IN THE FIRE WEATHER FORECAST.

&&

.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO 10 AM CDT
     THURSDAY FOR LMZ643>646.

&&

$$

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



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