FXUS63 KMKX 050939
AFDMKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
339 AM CST SUN FEB 5 2012

.SHORT TERM...

TODAY AND TONIGHT...FORECAST CONFIDENCE LOW TO MEDIUM.

ANOTHER TRICKY CLOUD FORECAST FOR THE NEXT 24 HOURS. LAKE MI
DELTA-T HAS INCREASED TO AROUND 8 DEGREES OVERNIGHT IN WEAK LOW
LEVEL COLD AIR ADVECTION BEHIND WEAK SFC FRONT WHICH HAS CAUSED
WINDS TO VEER TO THE NORTH TO NORTHEAST. BURST OF INCREASED LOW
LEVEL CONVERGENCE HAS USED SHALLOW MOISTURE TO PRODUCE LAKE CLOUDS
OVER WESTERN HALF OF SRN LAKE MI. THESE CLDS HAVE STREAMED INTO
LAKESHORE COUNTIES SINCE 07Z. THINKING THESE LAKE CLOUDS WL STICK
AROUND INTO THE MORNING BEFORE THINNING AND DISSIPATING AS THE LOW
LEVEL FLOW BEGINS TO BACK TO THE NORTH-NORTHWEST.

BESIDES LAKE INDUCED CLOUDS...N-NE WINDS HAVE BEEN CARRYING STRATUS
FIELD ACROSS NORTHEAST WI WITH LEADING EDGE GETTING CLOSE TO SBM/FDL
AREAS. HOWEVER WESTERN PART OF CLOUD EDGE NORTH OF AUW TO SHAWANO
HAS SLOWED ITS SWD PROGRESS SINCE 08Z...PERHAPS AS A RESPONSE TO
BUILDING HIGH PRESSURE AND SUBSIDENCE INTO THE AREA. WL KEEP CENTRAL
AND WRN CWA CLEAR TO P/CLOUDY FOR NOW.

AS LOW LEVEL FLOW TURNS TO THE WEST THIS AFTN AND EVE...WL NEED TO
KEEP EYE ON STRATUS FIELD OVER MN/IA. IT IS POSSIBLE THIS CLOUD
AREA COULD ADVECT INTO SRN WI TNGT. FOR NOW WL REMAIN WITH MORE
OPTIMISTIC P/CLDY WORDING DUE TO INCREASING BOUNDARY LAYER WINDS
MIXING DRIER AIR BELOW THE INVERSION.

MONDAY AND MONDAY NIGHT...FORECAST CONFIDENCE IS MEDIUM TO HIGH.

A COLD FRONT AND TROUGH ASSOCIATED WITH SURFACE AND 500MB LOW
PRESSURE OVER EASTERN QUEBEC WILL DROP SOUTHWARD ACROSS WISCONSIN ON
MONDAY. WINDS WILL SHIFT FROM WEST TO NORTHWEST MON AFTERNOON...AND
TO NORTH-NORTHEAST MON EVENING BEHIND THE FRONT. SKIES SHOULD BE
MOSTLY CLEAR ON MONDAY...DEPENDING ON HOW MANY CLOUDS NEED TO CLEAR
FROM LATE TONIGHT...SO TEMPS EXPECTED IN THE MID/UPPER 40S. THIS IS
THE HIGH END OF GUIDANCE...BUT SINCE TEMPS JUMPED INTO THE MID 40S
IN SOME LOCATIONS WITH SUNSHINE YESTERDAY UNDER A COOLER AIR
MASS...THIS IS NOT OUT OF THE QUESTION.

COLDER AIR AND LOW CLOUDS WILL RUSH INTO SOUTHERN WI MONDAY NIGHT
BEHIND THE FRONT. EXACT TIMING OF THE CLOUDS IS A LITTLE UNCERTAIN.
SOME MODELS HINT AT LIGHT SNOW POSSIBILITY...BUT THIS IS PROBABLY
DUE TO LOW LEVEL MOISTURE BEING OVERDONE...SO NO MENTION FOR PRECIP
WITH THE FRONT.

TUESDAY...FORECAST CONFIDENCE IS MEDIUM.

WITH THE NORTH-NORTHEAST WINDS AND THE LONG FETCH OF LAKE
MICHIGAN...SOUTHEAST WI HAS A CHANCE FOR LAKE EFFECT SNOW SHOWERS ON
TUESDAY. DELTA-T WILL BE AROUND 13-14C WITH LAKE INDUCED CAPE VALUES
OF ALMOST 200 AND A MIXING DEPTH OF AROUND 5000 FEET...JUST BARELY
IN THE DENDRITIC GROWTH ZONE ON THE GFS BUFKIT SNDG.

GFS AND NAM HANG ON TO THE NORTHEASTERLY WINDS LONGER THAN ECMWF
AND CANADIAN MODELS THROUGH TUE NIGHT...WITH THE OTHERS TURNING FLOW
TO THE NORTHWEST EARLIER.

COLDER TEMPS IN THE TEENS/LOWER 20S EXPECTED TUE NIGHT WITH HIGH
PRESSURE RIDGE OVERHEAD...ALTHOUGH IT WILL DEPEND ON HOW QUICKLY THE
CLOUDS CLEAR.

.LONG TERM...

WEDNESDAY AND WEDNESDAY NIGHT...FORECAST CONFIDENCE IS HIGH.

DRY WEATHER AND SEASONABLE TEMPS WITH HIGH PRESSURE IN PLACE.

THURSDAY THROUGH FRIDAY...FORECAST CONFIDENCE IS MEDIUM.

MODELS ARE STILL ADVERTISING ANOTHER LOW PRESSURE TROUGH DROPPING
SOUTHWARD ACROSS THE GREAT LAKES REGION LATER IN THE WEEK AND
BRINGING A STRONGER BLAST OF ARCTIC AIR INTO SOUTHERN WI BY NEXT
WEEKEND. TIMING DIFFERENCES ARE LESS THAN PREVIOUS RUNS...BUT ARE
STILL PRESENT. WENT WITH CONSENSUS OF ALL MODELS FOR TEMPERATURES IN
THE EXTENDED. THIS LOOKS LIKE A DRY SYSTEM AS WELL...HOWEVER THE GFS
MAINTAINS THE CHANCE FOR LIGHT PRECIP WITH IT. KEPT FCST DRY.

SATURDAY THROUGH SUNDAY...FORECAST CONFIDENCE IS MEDIUM.

UPPER TROUGH AND ASSOCIATED VORTICITY MAXIMUM WILL DROP DOWN ACROSS
THE UPPER GREAT LAKES REGION OVER THE WEEKEND...REINFORCING THE COLD
TEMPS IN PLACE. HIGHS EXPECTED IN THE 20S...WITH A POSSIBLE WARM-UP
INTO THE 30S ALREADY BY SUN OR MON. SLIGHT CHANCE FOR SNOW SHOWERS
WITH THE LOW LEVEL MOISTURE AND INSTABILITY FROM THE LAKE PUSHING
INLAND AT TIMES SAT NIGHT INTO SUNDAY.

&&

.AVIATION/12Z TAFS/...

LOW CLOUDS ASSOCD WITH WEAK LOW LEVEL CONVERGENCE AND LOW LEVEL COLD
AIR ADVECTION MOSTLY OVER ERN TAF SITES ARE EXPECTED TO THIN LATER
THIS MRNG AS LOW LEVEL FLOW BACKS TO THE NORTHWEST AND SUBSIDENCE
INCREASES. INCREASING W WINDS LATER TODAY AND TNGT MAY PULL LARGE
STRATUS SHIELD OVER MN/IA ACROSS WI...BUT WL HOLD OFF FROM
INTRODUCING ANY CIGS IN TAFS FOR NOW DUE TO INCREASING BOUNDARY
LAYER MIXING OF DRY AIR AT AND SLIGHTLY BELOW INVERSION LEVEL.

&&

.MARINE...GUSTY NORTH TO NORTHEAST WINDS ASSOCD WITH LOW LEVEL WEAK
COLD AIR ADVECTION WILL WEAKEN THIS MRNG AS LOW LEVEL FLOW BEGINS TO
BACK TO THE NORTHWEST. THIS WILL BE ASSOCD WITH LOW-MID LEVEL
RIDGING INCREASING ACROSS WISCONSIN AND LAKE MI FROM THE NRN PLAINS
AS LOW PRESSURE IN THE TN VALLEY MOVES FARTHER EAST. STRONGER CDFNT
IS EXPCD TO SWEEP ACROSS LAKE MI MON EVE WITH NORTHEAST WINDS AND
RESULTANT WAVES REACHING SMALL CRAFT ADVY LEVELS LATER MON NGT INTO
TUE.

&&

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

$$

TODAY/TONIGHT AND AVIATION/MARINE...MBK
MONDAY THROUGH SATURDAY...MRC



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