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000
FXUS63 KMKX 302125
AFDMKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
325 PM CST FRI JAN 30 2015

.SHORT TERM...

TONIGHT AND SATURDAY...FORECAST CONFIDENCE IS MEDIUM.

MODELS IN GOOD AGREEMENT WITH HIGH PRESSURE SLIDING TO THE SOUTHEAST
OF THE AREA TONIGHT...WITH WARM AIR ADVECTION DEVELOPING LATER
TONIGHT INTO SATURDAY MORNING.

MAIN ISSUE WILL BE POTENTIAL CLEARING OF MIDDLE LEVEL CLOUDS LATER
THIS EVENING INTO SATURDAY MORNING. MESOSCALE MODELS ARE SHOWING
THESE CLOUDS SLIDING EAST OF THE AREA LATER THIS EVENING...WITH A
PERIOD OF MOSTLY CLEAR SKIES LATER TONIGHT INTO SATURDAY MORNING.
SYNOPTIC MODELS ALSO HINTING AT THIS.

TRENDED DOWNWARD IN THE SKY COVER FORECAST FOR LATER TONIGHT INTO
SATURDAY MORNING...BUT STILL MAY NOT BE CLEAR ENOUGH GIVEN MODEL
TRENDS. LATER SHIFTS WILL NEED TO MONITOR TRENDS.

LIGHT SOUTHWEST WINDS TONIGHT WILL WEAKEN FOR A TIME SATURDAY...WITH
A COLD FRONT SLIDING SOUTHWARD THROUGH THE AREA IN THE LATE MORNING
AND AFTERNOON. WINDS WILL SHIFT NORTH TO NORTHEAST BEHIND THE COLD
FRONT...WHICH SHOULD THEN STALL SOUTH OF THE AREA.

TEMPERATURES SHOULD FALL SOMEWHAT THIS EVENING...THEN REMAIN STEADY
OR SLOWLY RISE LATER TONIGHT WITH THE WARM AIR ADVECTION. MILD HIGHS
IN THE LOWER TO MID 30S ARE EXPECTED SATURDAY.

SATURDAY NIGHT THROUGH MONDAY...FORECAST CONFIDENCE MEDIUM.

FOR SAT NT...A SHORTWAVE TROUGH WILL DIG SEWD FROM THE NRN HIGH
PLAINS AND INTO NE BY 12Z SUN WITH A STRONGER SHORTWAVE TROUGH
LOCATED JUST UPSTREAM. A LEAD SHORTWAVE TROUGH OVER THE MID MO
RIVER VALLEY AHEAD OF THE AFOREMENTIONED FEATURES WILL MOVE INTO
SRN WI LATE SAT NT WHILE THE RRQD OF A 140 KT JET SETS UP OVER
SRN WI. 850 MB FRONTOGENESIS WILL PROVIDE MESOSCALE LIFT...AIDED
BY PVA AND JET DYNAMICS AS SNOW OVERSPREADS SRN WI SAT NT.

AS THE UPPER TROUGH DIGS AND DEEPENS OVER THE MID MO RIVER VALLEY
ON SUN...CYCLOGENESIS WILL ENSUE FROM WRN MO TO ALONG THE OHIO
RIVER FOR SUN AFT AND NIGHT. THE AFOREMENTIONED LIFTING PROCESSES
WILL CONTINUE WITH DEEPER AND MORE ORGANIZED FRONTOGENESIS
EXPECTED TO CLIP SE WI FOR SUN INTO EARLY SUN EVE. LAKE EFFECT
SNOW WILL BE A FACTOR DURING THIS ENTIRE PERIOD AS A 1000-850 MB ENELY
FLOW WILL BECOME ESTABLISHED SAT NT AND BECOME NNELY FOR SUN NT.
LAKE TO 850 MB TEMP DIFFERENCES WILL START AT 13-17C EARLY SUN AND
END AROUND 20C SUN NT. THE LAKE EFFECT SNOW CHART SUGGESTS AT
LEAST A FEW INCHES OF MORE SNOW IS EXPECTED IN FAR ERN WI VERSUS
FARTHER INLAND LOCATIONS.

NWS OFFICES HAVE USED A CONSERVATIVE AMOUNT OF QPF DUE TO A HIGH
BIAS ON SOME OF THE MODELS AND SOME UNCERTAINTY WITH THE MODELS
WAVERING NORTH AND SOUTH. ALSO THE OVERALL LIFT OVER SRN WI IS
CONSIDERED A MODERATE AMOUNT OF LIFT...WITH THE EXCEPTION OF ANY
LES BANDS. NEVERTHELESS...COLD TEMPS SUPPORT HIGH RATIOS. THE
SNOWFALL FORECAST RANGES FROM 2-3 INCHES OVER CENTRAL WI TO 6-9
INCHES IN FAR SE WI. ONSHORE WIND GUSTS FROM LAKE MI WILL LIKELY
REACH 30 MPH OR GREATER AT TIMES WITH CONSIDERABLE BLOWING AND
DRIFTING SNOW. THUS ISSUED A WINTER STORM WATCH FOR
MILWAUKEE...RACINE...AND KENOSHA COUNTIES. BLOWING AND DRIFTING
SNOW WILL ALSO IMPACT ALL OF SRN WI AS WELL. WINTER WX HEADLINES
WILL EVENTUALLY BE IN EFFECT FOR MUCH OF SRN WI STARTING SAT NT.
POLAR HIGH PRESSURE AND VERY COLD TEMPS TO FOLLOW FOR MONDAY.


.LONG TERM...WARM ADVECTION AND A SHORTWAVE TROUGH WILL BRING
CHANCES OF SNOW FOR MON NT BUT WILL BE FOLLOWED BY A MUCH LARGER
DIGGING UPPER TROUGH FOR THE MIDDLE OF THE WEEK. A SFC TROUGH AND
COLD FRONT WILL PASS AHEAD OF THE UPPER TROUGH FOR TUE AFT AND
NIGHT WITH SNOW CHANCES CONTINUING. ARCTIC AIR WILL THEN ADVECT
INTO THE AREA WED AND WED NT FOLLOWED BY AN ARCTIC HIGH PRESSURE
AREA FOR THU. THE HIGH MAY MOVE EAST BY FRI WITH SWLY WINDS AND
WARM ADVECTION. WIND CHILL TEMPS WILL APPROACH 20 BELOW ZERO LATE
WED NT INTO THU AM.


&&

.AVIATION/00Z TAFS/...VFR CONDITIONS ARE EXPECTED TONIGHT AND SATURDAY
ACROSS TAF SITES. SCATTERED TO BROKEN MIDDLE LEVEL CLOUDS WILL
CONTINUE TO PUSH SOUTHEAST THROUGH THE AREA INTO THIS EVENING.
THESE CLOUDS MAY PUSH OFF TO THE EAST BY LATE EVENING...WITH A
PERIOD OF MOSTLY CLEAR SKIES POSSIBLE LATER TONIGHT INTO SATURDAY
MORNING.

LIGHT WINDS WILL BECOME SOUTHWEST EARLY THIS EVENING...THEN
GRADUALLY INCREASE LATER TONIGHT INTO EARLY SATURDAY. THE WINDS WILL
WEAKEN AGAIN SATURDAY...BEFORE A COLD FRONT MOVES SOUTH INTO THE
AREA MAINLY IN THE AFTERNOON. THIS WILL BRING A WIND SHIFT TO THE
NORTHEAST BY 00Z SUNDAY.

&&

.MARINE...

A TIGHT PRESSURE GRADIENT IS EXPECTED TO DEVELOP ACROSS THE REGION
SATURDAY NIGHT INTO SUNDAY NIGHT...AS LOW PRESSURE PASSES TO THE
SOUTH OF THE REGION. THIS WILL BRING GUSTY ONSHORE WINDS SATURDAY
NIGHT AND SUNDAY...BECOMING MORE OFFSHORE SUNDAY NIGHT INTO EARLY
MONDAY. GUSTS TO 30 KNOTS ARE POSSIBLE DURING THIS PERIOD.

THE ONSHORE WINDS SHOULD BRING HIGH WAVES UP TO 6 TO 10 FEET ACROSS
THE NEARSHORE WATERS SUNDAY INTO SUNDAY NIGHT. FREEZING SPRAY IS
ALSO POSSIBLE DURING THIS PERIOD. THUS...A SMALL CRAFT ADVISORY WILL
LIKELY BE NEEDED IN LATER FORECASTS FOR SATURDAY NIGHT INTO EARLY
MONDAY.


&&

.MKX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER STORM WATCH FROM LATE SATURDAY NIGHT THROUGH LATE SUNDAY
     NIGHT FOR WIZ066-071-072.

LM...NONE.
&&

$$

TONIGHT/SATURDAY AND AVIATION/MARINE...WOOD
SATURDAY NIGHT THROUGH FRIDAY...GEHRING