sunprairieweather

000
FXUS63 KMKX 030839
AFDMKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
339 AM CDT FRI SEP 3 2010

TODAY AND TONIGHT...FORECAST CONFIDENCE...MEDIUM

COLDER AIR CURRENTLY WORKING INTO SOUTHERN WISCONSIN BEHIND FRONT
THAT PUSHED THROUGH LAST EVENING. UPPER WAVE WILL DROP THROUGH
TODAY...WITH COLDEST AIR ALOFT ARRIVING THIS AFTERNOON. WITH MODELS
SHOWING 850 MB TEMPS DROPPING TO AROUND 5C BY AFTERNOON...HIGHS WILL
STRUGGLE QUITE A BIT...ASIDE FROM EARLY TEMPERATURE RISES IN THE
SOUTHEAST WHERE MILDER AIR WILL LINGER LONGER. ADDITIONALLY...SHOULD
SEE QUITE A BIT OF CLOUDS AND EVENTUALLY SOME SHOWERS ACROSS MUCH OF
THE AREA...AS PASSING WAVE WILL PROVIDE SOME LIFT WITH STEEP LOW
LEVEL LAPSE RATES AS COLDER AIR MOVES OVERHEAD. KEPT ISOLATED
SHOWERS IN THE NORTH THIS MORNING TO ACCOUNT FOR A FEW SHOWERS
UPSTREAM. NOT REALLY EXPECTING SHOWERS TO GET GOING ACROSS THE AREA
UNTIL LATE MORNING AND INTO THE AFTERNOON AS COLDEST AIR MOVES
OVERHEAD...TIMED WELL WITH WHAT DAYTIME HEATING THERE WILL BE.

OTHER CONCERN TODAY WILL BE THE WINDS. DEEPENING SFC LOW PRESSURE
OVER LAKE SUPERIOR WILL PRODUCE A TIGHTENING PRESSURE GRADIENT
ACROSS THE FORECAST AREA THIS MORNING AND INTO THE AFTERNOON. MODEL
SOUNDINGS SHOW THE POSSIBILITY OF GUSTS TO 40 MPH WITH DECENT MIXING
THIS AFTERNOON...ESPECIALLY IN THE EAST. PROBLEM WILL BE HOW QUICK
THINGS CLOUD UP...AS EXPECTING MOSTLY CLOUDY CONDITIONS BY MID
AFTERNOON...IF NOT EARLIER. CLOUDINESS SHOULD HELP TO HOLD BACK
HIGHEST GUST POTENTIAL...WITH GUSTS TO 35 MPH MORE REASONABLE. WILL
FEEL QUITE A BIT LIKE FALL AS CLOUDS AND WINDS COMBINE WITH HIGH
TEMPS IN THE 60S.

WINDS SHOULD DIMINISH LATE AFTERNOON AND INTO THE EVENING AS LOW
CONTINUES TO SLIDE EAST AND DAYTIME HEATING IS LOST. SHOULD SEE
SHOWERS COME TO END AS WELL...SO KEPT EVENING FORECAST DRY. SHOULD
SEE LOWS IN THE 40S MOST PLACES. LEANED TOWARD THE MILDER NAM...AS
GFS SEEMS TO BE TOO LOW GIVEN DECENT PRESSURE GRADIENT SHOULD KEEP
WINDS FROM GETTING THAT LIGHT.

SATURDAY...FORECAST CONFIDENCE...HIGH

ANOTHER COOL DAY ON SATURDAY AS COLDER AIR ALOFT LINGERS. WILL STILL
BE BREEZY IN THE AFTERNOON...BUT OVERALL LIGHTER WINDS AND QUITE A
BIT MORE SUNSHINE SHOULD MAKE FOR A NICE DAY.

SUNDAY THROUGH TUESDAY...FORECAST CONFIDENCE...LOW TO MEDIUM

WINDS TURN SRLY ON SUNDAY AHEAD OF NEXT APPROACHING SYSTEM. NAM
SEEMS TO QUICK WITH WAA GIVEN OTHER MODELS...SO KEPT FORECAST DRY.
SHOULD SEE MORE CLOUDS AND A SLIGHT CHANCE FOR SHOWERS AND STORMS
SUNDAY NIGHT INTO MONDAY AS WAA KICKS INTO FULL GEAR. TEMPS WILL
WARM QUICKLY TO THE MID 70S BY SUNDAY...AND THEN THE LOWER 80S ON
LABOR DAY. KEPT A SLIGHT CHANCE FOR SHOWERS AND STORMS SOME PLACES
MONDAY...BUT MOST ACTIVITY SHOULD BE CONFINED TO THE NORTH AS WARM
FRONT CONTINUES TO LIFT NORTH.

WENT WITH SLIGHT CHANCE SHOWERS AND STORMS FOR TUESDAY AS COLD
FRONT APPROACHES. MILDER WEATHER WILL CONTINUE WITH UPPER 70S TO
LOWER 80S EXPECTED.

&&

.AVIATION...

CLEAR SLOT OCCURRING EARLY THIS MORNING BUT THEN EXPECT SOME MVFR
CIGS WITH APPROACHING STRATOCUMULUS SHIELD FROM THE NORTHWEST.

MVFR CIGS WOULD RISE TO 35 HNRD TO 5 THSD FT THIS AFTERNOON.

SUSTAINED WEST NORTHWEST WINDS TO 20 KNOTS...WITH GUSTS TO 30
KNOTS...ARE EXPECTED BY AFTERNOON...WITH GOOD MIXING OF LOW LEVEL
WINDS TO THE SURFACE.

A FEW AFTERNOON SHOWERS ARE POSSIBLE WITH NAM SOUNDINGS SHOWING
STEEP LAPSE RATES AND MOISTURE THROUGH 9 THSD FT...ESPECIALLY AS MID
LEVEL TROUGH AXIS MOVES THROUGH.

&&

.MARINE...

A TIGHT PRESSURE GRADIENT AND DOWNWARD MIXING OF 33 KNOT 1000 FOOT
WINDS TO THE SURFACE ARE EXPECTED LATER TODAY. THUS...FREQUENT WIND
GUSTS TO 30 KNOTS ARE EXPECTED ACROSS THE NEARSHORE WATERS DURING
MOST OF THIS PERIOD.

MODELS SHOW SOME POTENTIAL FOR 35 KNOT GUSTS MIXING DOWN TO THE
SURFACE THIS AFTERNOON AND NIGHT. GIVEN STRONG COLD AIR ADVECTION
AND WARM WATERS...IT WOULD BE POSSIBLE FOR 35 KNOT GALES TO MIX
DOWN. OCCASIONAL GUSTS TO GALES ARE EXPECTED ESPECIALLY TOWARD OPEN
WATERS.

WILL THEREFORE KEEP SMALL CRAFT ADVISORY GOING UNTIL 18Z THIS
AFTERNOON.  THEN GALE WARNING TIL 06Z TONIGHT.


&&

.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 1 PM CDT THIS AFTERNOON FOR
     LMZ643>646.

     GALE WARNING FROM 1 PM THIS AFTERNOON TO 1 AM CDT SATURDAY FOR
     LMZ643>646.

&&

$$

SHORT/LONG TERM...DDV/07
AVIATION/MARINE...HENTZ/06
NWS MKX Office Area Forecast Discussion