Area Forecast Discussion
Issued by NWS Milwaukee/Sullivan, WI

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000
FXUS63 KMKX 150210
AFDMKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
910 PM CDT TUE OCT 14 2014

.UPDATE...
DRIER AIR WORKING IN BEHIND INVERTED TROUGH AS SECONDARY
SURFACE CYCLOGENESIS TAKES PLACE OVER WESTERN LOWER MICHIGAN HAS
ERODED PCPN AS IT ROTATES AROUND MAIN LOW CENTERED OVER EAST-
CENTRAL IL. HAVE REDUCED QPF IN NW CWA AND MAY HAVE TO LOWER POPS
EVEN MORE THERE WITH MAINLY AREAS OF LIGHT DRIZZLE BEING
REPORTED...WITH ISOLATED TO SCATTERED SHOWERS AT BEST PER LATEST
RUNS OF THE HI-RES/RAPID UPDATE MODELS. EASTERN CWA STILL HAS
BETTER CHANCE OF MORE WIDESPREAD SHOWERS INTO THE OVERNIGHT HOURS.

&&

.AVIATION/06Z TAFS/...

DRIER AIR WORKING IN BEHIND INVERTED TROUGH AS SECONDARY
SURFACE CYCLOGENESIS TAKES PLACE OVER WESTERN LOWER MICHIGAN HAS
ERODED PCPN AS IT ROTATES AROUND MAIN LOW CENTERED OVER EAST-
CENTRAL IL. CIGS HAVE ALSO RISEN OVER THE WESTERN CWA WITH POCKETS
OF MVFR CIGS BETWEEN 2K AND 3K FT REACHING KMSN. WILL BRING MVFR
CIGS FOR A TIME TO KMSN...BUT WILL HAVE PREVAILING IFR RETURNING
AFTER 06Z AS LOW-LVL RH FORECASTS AND CLOUD COVER PROBABILITIES
HAVE LOW LEVEL MOISTURE PUSHING BACK TO THE WEST AROUND THE SFC LOW
AS IT CONSOLIDATES OVER LAKE MICHIGAN. TIGHT GRADIENT AROUND LOW
WILL KEEP NORTH WIND GUSTS AROUND 20 KTS INTO THE EARLY OVERNIGHT
HOURS.

&&

.MARINE...

NEAR-GALE FORCE GUSTS THIS EVENING AROUND 30 KTS WILL SLOWLY EASE
AFTER 03Z AS 1000 FT WINDS LOWER TO AROUND 25 KTS BY 06Z IN THE
SOUTH...AND 12Z WED IN THE NORTHERN ZONES. CURRENT DIMINISHING
TREND TO WINDS IN FORECAST WILL ALLOW WAVES TO SUBSIDE BELOW
SMALL CRAFT LEVELS BY LATE WED AFTERNOON END TIME...THOUGH LATEST
NAM HAS A BRIEF RISE TO NORTH WINDS LATE IN THE AFTERNOON SO LATER
SHIFTS WILL HAVE TO LOOK OVER COMPLETE 00Z DATA SET FOR POSSIBLE
EXTENSION IF HIGHER THAN EXPECTED AFTERNOON WINDS HOLD WAVE
HEIGHTS UP.

&&

.PREV DISCUSSION... /ISSUED 403 PM CDT TUE OCT 14 2014/

TONIGHT...FORECAST CONFIDENCE MEDIUM.

THE OCCLUDED SURFACE LOW IS CENTERED OVER CENTRAL IL. THIS SYSTEM IS
CAUSING SEVERAL COMPLEX WEATHER FEATURES OVER SOUTHERN WI WHERE THE
SURFACE/925MB FRONT EXTENDS NORTHWARD FROM THE LOW. ALL BUT FAR
SOUTHEAST WI NEAR KENOSHA HAVE SWITCHED OVER TO NORTHERLY WINDS WITH
THIS FRONT. THE WINDS ARE SHIFTING TO THE NORTH AND INCREASING JUST
BEHIND THE FRONT. THE HIGHEST WINDS ARE ACCELERATING DOWN THE
LAKESHORE FASTER THAN JUST INLAND.

ANOTHER THING THAT HAPPENED EARLY THIS AFTERNOON WAS STRONG WINDS
DEVELOPED IN THE WAKE OF PRECIP ENDING FROM SOUTH TO NORTH. WINDS
GUST TO 50 MPH IN SHEBOYGAN AROUND 1 PM WITH THIS FEATURE. THE WIND
GUSTS HAVE COME DOWN TO 35-40 MPH LATE THIS AFTERNOON... AND WILL
CONTINUE TO DIMINISH EARLY THIS EVENING.

12Z MODELS CAME IN WITH SLIGHTLY LESS PRECIP THAN PREVIOUS RUNS FOR
TONIGHT. THE MESOSCALE MODELS SUPPORT THE LIGHTER SOLUTION FOR
TONIGHT. THE HRRR HAS HAD A PRETTY GOOD HANDLE ON PRECIP COVERAGE
ALL DAY. THE NEXT BETTER-DEFINED ROUND OF RAIN IS EXPECTED WITH A
SHORTWAVE ROTATING AROUND THE UPPER LOW THAT IS PROGGED TO SWING
SOUTHWEST THROUGH THE MKX AREA AROUND MIDNIGHT THROUGH 4 AM. THE
EAST HALF OF THE MKX AREA WILL HAVE THE BEST CHANCE FOR RAIN
SHOWERS.

WEDNESDAY...FORECAST CONFIDENCE MEDIUM.

THE CHANCE FOR RAIN SHOWERS WILL CONTINUE THROUGH WEDNESDAY AS THE
UPPER LOW AND SURFACE LOW DRIFT THRUOGH INDIANA AND SHORTWAVE ENERGY
CONTINUES TO ROTATE AROUND THEM THROUGH SOUTHEAST WI. EXPECTING
COOLER TEMPS WEDNESDAY THAN WHAT THEY WERE TODAY... WITH HIGHS IN
THE MID 50S. EXPECT BRISK NORTH WINDS WITH GUSTS AROUND 20-23 MPH.

WEDNESDAY NIGHT AND THURSDAY - CONFIDENCE...MEDIUM
BROAD AND DOMINATING UPPER LOW CIRCULATION SLOWLY SHIFTS INTO THE
OHIO VALLEY THIS PERIOD. SOME DIFFERENCES WITH RESPECT TO HOW
QUICK SE WI EXITS THE INFLUENCE OF THE CYCLONIC FLOW ON THE
NORTHWEST WIDE OF THIS CIRCULATION...BUT FOR THE MOST PART LOOK
LIKE MIDDAY THURSDAY AND INTO THE AFTERNOON...THE MID LEVEL
RIDGING TAKES HOLD. WILL LINGER SHRA CHANCES INTO WEDNESDAY NIGHT
BUT EVEN WITH THE NEW TAM COMING AROUND TO A DRIER SCENARIO
THURSDAY...WILL GO THE DRY ROUTE. THE TAM HANGS ONTO MORE LVL RH
INTO THURSDAY WITH THE GFS AND ECMWF MORE AGGRESSIVE ON CLEARING
THINGS OUT. 925 TEMPS AVERAGE 9-12C SO ANY SUN WOULD ALLOW TEMPS
TO NUDGE INTO THE LOW 60S.

FRIDAY - CONFIDENCE...MEDIUM
SHORTWAVE TREKS TO OUR NORTH WITH LOW LEVEL THERMAL RIDGE
POSITIONED INTO SE WI EARLY IN THE DAY. LOW LEVEL COLD AVECTION
RAMPS UP A BIT ON INCREASING NW WINDS. CONSENSUS OF MODELS IS TO
KEEP ANY PRECIP TO OUR NORTH. 12Z ECMWF HAS SAGGED SOME QPF
FURTHER FRIDAY NIGHT BUT FOR THE MOST PART THIS IS AN OUTLIER.

SATURDAY - CONFIDENCE...MEDIUM
LOOKS LIKE A PRETTY QUIET NORTHWEST FLOW WITH SURFACE HIGH MOVING
A BITY CLOSER FROM THE PLAINS. WILL HAVE TO WATCH THE TRENDS WITH
THE ECMWF SHOWING A WETTER LOOK BUT GFS/GEM BOTH DERY. INFLUENCE
OF THE LOW LEVEL COOL POOL IN PLACE WITH 925 TEMPS DOWN TO 3-5C.

SUNDAY - CONFIDENCE...MEDIUM
MID LEVEL RIDGING WILL GIVE WAY TO INCREASING INFLUENCE OF
SHORTWAVE DIVING INTO THE PLAINS. SOME DIFFERENCES ON HOW
AMPLIFIED THIS FEATURE WILL BE THOUGH ECMWF AND GEM SHOW A FAIRLY
DECENT PORT WHILE THE GFS IS WEAKER. 12Z ECMWF HAS BACKED OFF A
BIT ON BRINGING PRECIS INTO WESTERN CWA BEFORE THE DAY IS OUT.
FOR NOW WENT WITH THE  POPS WHICH HAS A SLIGHT CHANCE INTO THE
WEST. MUCH OF THE AREA LOOKS DRY WITH POTENTIAL FOR INCREASING
CLOUDS AHEAD OF THE WAVE AND WITH WAN KICKING IN. LATER SHIFTS
MAY BE ABLE TO ELIMINATE THIS POP IF THE DRY TREND BECOMES
CONSISTENT.

SUNDAY NIGHT AND MONDAY - CONFIDENCE...LOW
LOTS OF MODEL VARIABILITY THIS PERIOD WITH BOTH THE GFS AND GEM
SHOWING A STRONGER WAVE WITH BIG TIMING DIFFERENCES...WHILE THE
ECMWF SHOWING A WEAKER POSITIVE TILT WAVE WITH LITTLE OR NO
PRECIS. HAVE KEPT  POPS IN PLACE FOR NOW BUT IF WEAKER SOLUTION
OF THE ECMWF BECOMES THE PREVAILING IDEA THEN POP REDUCTION OR
REMOVAL WOULD BECOME NECESSARY.

TUESDAY - CONFIDENCE...MEDIUM
MODELS IN DECENT AGREEMENT OF NORTHWEST ANTICYCLONIC FLOW AROUND
THE PRONOUNCED UPPER RIDGE BUILDING THROUGH THE PLAINS. LARGE
SURFACE HIGH LOOKS TO BUILD IN ACROSS THE GREAT LAKES REGION WITH

AVIATION/00Z TAFS/...

LOW PRESSURE WILL SLOWLY MOVE ACROSS ILLINOIS AND INDIANA THROUGH
WEDNESDAY WITH THE TROUGH AXIS EXTENDING NORTHWARD INTO SOUTHEAST
WISCONSIN. GUSTY NORTH WINDS IN THE WAKE OF A FRONT WILL PERSIST
THROUGH THE NIGHT. HIGHEST GUSTS WILL BE LATE THIS AFTERNOON INTO
THE EARLY EVENING HOURS. EXPECT WIND GUSTS OF 25 TO 30 KNOTS AT
TIMES.

EXPECT IFR CIGS THROUGH THE NIGHT IN SOUTHEAST WI. SOUTH CENTRAL
WI...MSN... COULD SEE CIGS RISE TO 1000-1500 FEET JUST PRIOR TO 12Z
WED. EXPECT SOUTHEAST WI CIGS TO LIFT TO 1000-1500 FT AFTER 12Z THEN
ABOVE 2000 FT BY WED AFTERNOON. THIS IS MORE PESSIMISTIC THAN THE
PREVIOUS FORECAST/ 18Z TAF.

SHOWERS OVER FAR SOUTHERN AND WESTERN WI WILL MOVE OUT THIS EVENING.
ANOTHER ROUND OF SHOWERS IS LIKELY NEAR SHEBOYGAN AROUND MIDNIGHT...
SPREADING DOWN THE LAKESHORE COUNTIES THROUGH EARLY MORNING.

MARINE...

NORTHEAST WINDS IN THE WAKE OF A FRONT WERE EXCEEDING GALE FORCE
EARLY THIS AFTERNOON AND ARE NOW DROPPING DOWN BELOW THAT LEVEL. A
FEW WIND GUSTS COULD STILL REACH GALE FORCE THIS EVENING FROM PORT
WASHINGTON SOUTH TO KENOSHA AS THE FRONT MAKES ITS WAY DOWN THE
LAKE.

WINDS WILL GRADUALLY DIMINISH TO 15 TO 20 KNOTS OVERNIGHT WITH GUSTS
TO 25 KNOTS. THESE WILL PERSIST THROUGH WED AFTERNOON.

&&

.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 4 PM CDT WEDNESDAY FOR LMZ643>646.

&&

$$

UPDATE...REM
TONIGHT/WEDNESDAY AND AVIATION/MARINE...MRC
WEDNESDAY NIGHT THROUGH TUESDAY...COLLAR



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