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000
FXUS63 KMKX 111619
AFDMKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
1119 AM CDT FRI APR 11 2014

.AVIATION/18Z TAFS/...MID DECK WITH ASSOC R- SWINGING THROUGH SRN
WI THIS AFTN. SHORTWAVE AND WAA DRIVING THE FORCING. PLENTY OF DRY
AIR TO OVERCOME BUT GETTING SOME GROUND TRUTH IN WRN WI. BASES
WILL REMAIN AT VF LEVELS INTO THIS EVE WITH SKC UPSTREAM IN
SRN/CNTRL MN. RENEWED 850 MILLIBAR JET CORE WILL DRIVE ADDITIONAL
SHRA DEVELOPMENT SAT MRNG. AFTN DEVELOPMENT QUESTIONABLE WITH
ENTRANCE REGION OF 850 JET CORE BECOMING MORE PREDOMINANT. MODELS
ALL SHOWING MORE PRECIP DURG THE AFTN BUT FORCING ALOFT LOOKS
MINIMAL. LOW LEVEL TROUGH NUDGES INTO CWA BUT MOISTURE STILL
QUESTIONABLE...WITH BETTER CONVERGENCE HANGING BACK INTO SW WI.
NOT CONFIDENT THAT AFTN PRECIP WILL EXTEND AS FAR EAST AS MODELS
SUGGEST.

PC

&&

.PREV DISCUSSION... /ISSUED 358 AM CDT FRI APR 11 2014/

TODAY AND TONIGHT...FORECAST CONFIDENCE IS MEDIUM.

VERY LIGHT RAIN SHOWERS IN CENTRAL TO SWRN MN ON NOSE OF FOCUSED
WARM ADVECTION AHEAD OF SHORT WAVE THAT CROSSES NRN/CENTRAL
WISCONSIN THIS AFTERNOON. WHILE ISENTROPIC LIFT IS DECENT MOISTURE
IS LACKING. STILL BUFKIT FORECAST SOUNDINGS OVER NORTHERN SITES FOR
TODAY SIMILAR TO 11/00Z BIS AND ARB RAOBS REFLECTING ABOUT A 3K FOOT
DEEP CLOUD LAYER AND DRY LAYER BELOW 730 MB THAT IS STILL ALLOWING
LIGHT PCPN/SPRINKLES TO REACH THE SURFACE. WILL KEEP SLIGHT CHC POPS
ACROSS THE NORTH.

DRY COLUMN ALLOWING DEEP MIXING WITH FORECAST LOW TO MID-20S DEW
POINTS POSSIBLY NOT LOW ENOUGH GIVEN MIX OUT DEW POINTS IN THE TEENS
IN THE DAKOTAS THURSDAY AFTERNOON SIMILAR TO WHAT OCCURRED OVER SRN
WI. DEEP MIXING AND POSSIBLY A SUPER ADIABATIC BUMP AT THE SURFACE
LEADS TO MID TO UPPER 60 HIGHS...MAYBE A 70 IN THE WEST. DOWNWARD
MOMENTUM TRANSFER ALLOWS SOUTHWEST WINDS TO GUST BETWEEN 25 AND 30
MPH.

WINDS DROP OFF AFTER PASSAGE OF WAVE AS WEAK HIGH MOVES OVER WITH
LIGHT AND VARIABLE WINDS. WINDS THEN BEGIN TO INCREASE FROM THE EAST
AFTER 06Z WITH APPROACH OF LOW FROM THE DAKOTAS. EXPECT LOWS TO
HOLD;D IN THE 40S...WITH DEVELOPING EAST WINDS BRINGING UPPER 30S
ALONG THE LAKE.

SATURDAY THROUGH MONDAY...FORECAST CONFIDENCE...MEDIUM

MODELS CONTINUE TO SUGGEST A PROLONGED PERIOD OF WET WEATHER THIS
WEEKEND INTO EARLY NEXT WEEK. THE FIRST ROUND OF PRECIP IS
EXPECTED ON SATURDAY...AS A SFC WARM FRONT SETS UP NEAR OR NORTH
OF THE NORTHERN FORECAST AREA. ADDITIONALLY...STRONG WARM
ADVECTION IS EXPECTED ALOFT...AND A SHORTWAVE SHOULD PROVIDE
ADDITIONAL LIFT. THE BIGGEST POSSIBLE ISSUE WITH PRECIP DURING
THIS PERIOD WILL BE DRY AIR. THOUGH MODELS SHOW A DECENT AMOUNT OF
RAIN...SOUNDINGS STILL SHOW RESPECTABLE POCKETS OF DRY AIR IN THE
MID AND LOW LEVELS THROUGH THE DAY. BANKING ON ENOUGH LIFT TO
OVERCOME THE DRIER AIR FOR NOW. LOOKS LIKE ENOUGH INSTABILITY FOR
A MENTION OF THUNDER THROUGH THE DAY.

TEMPERATURES WILL BE TRICKY SATURDAY...ALL DEPENDING ON WHERE
EXACTLY THE WARM FRONT SETS UP...AND HOW MUCH OF AN INFLUENCE THE
LAKE WILL HAVE. A SHARP GRADIENT IN TEMPERATURES IS EXPECTED
ACROSS THE AREA...IT IS JUST A MATTER OF DECIDING EXACTLY WHERE
THAT TRANSITION FROM LOW 50S TO LOW 70S WILL BE. RIGHT NOW...IT
LOOKS LIKE THE TRANSITION AREA WILL BE RIGHT ACROSS SOUTHERN
WISCONSIN. FORECAST HIGHS RANGE FROM THE 50S IN THE FAR NORTHEAST
FORECAST AREA...TO AROUND 70 ALONG THE ILLINOIS BORDER. THESE
TEMPS ARE CERTAINLY SUBJECT TO CHANGE IF THE FRONT ENDS UP BEING
FARTHER NORTH OR SOUTH.

THE SFC FRONTAL BOUNDARY WILL SLOWLY SAG SOUTHWARD SATURDAY
NIGHT...WITH SHOWERS AND STORMS EXPECTED AS A RESULT. MODELS HAVE
THE SFC BOUNDARY SOUTH OF THE ILLINOIS BORDER BY SUNDAY
MORNING...WITH ONLY THE NAM SNEAKING IT NORTH OF THE WI/IL BORDER
DURING THE DAY. TEMPS ARE THUS EXPECTED TO BE QUITE A BIT COOLER
THAN ON SATURDAY.

MODELS ARE SHOWING QUITE A BIT OF LIFT DUE TO FRONTOGENETICAL AND
ISENTROPIC FORCING SUNDAY AND SUNDAY NIGHT...AS SURFACE LOW
PRESSURE PASSES BY TO THE SOUTHEAST. THUNDER CHANCES WILL CONTINUE
INTO THE EVENING.

TEMPS CRASH SUNDAY EVENING AND OVERNIGHT...BRINGING A LIKELY
CHANGEOVER TO SNOW FROM NORTHWEST TO SOUTHEAST. MODELS VARY AS TO
HOW MUCH PRECIP WILL FALL AFTER TEMPS ARE COLD ENOUGH FOR SNOW.
TAKING A CONSENSUS APPROACH...ENDED UP WITH AROUND 2 INCHES OF
ACCUMULATION BY THE TIME THE PRECIP WINDS DOWN MONDAY MORNING. NOT
SURE HOW WELL THE SNOW WILL ACCUMULATE AFTER THE PERIOD OF MILDER
TEMPS...BUT DEFINITELY LOOKS LIKE THERE COULD BE SOME ON THE
GROUND BY MORNING. LOOKS CHILLY THROUGH THE DAY MONDAY...WITH
HIGHS ONLY TOPPING OUT IN THE UPPER 30S AND LOW 40S.

TUESDAY THROUGH THURSDAY...FORECAST CONFIDENCE...LOW

COLDEST TEMPS ALOFT TO SLIDE WILL BE OVERHEAD TUESDAY...WITH A
SLIGHT CHANCE FOR SNOW AS THE MAIN TROUGH AXIS MOVES THOUGH.

MODELS DIVERGE QUITE A BIT FOR MID WEEK. THE GFS STAYS COLDER FOR
WEDNESDAY AND THURSDAY...BRINGING SOME LIGHT SNOW ACCUMULATIONS.
THE ECMWF IS MILDER AND MAINLY DRY.

AVIATION/12Z TAFS/...

EXPECT DRY CONDITIONS AT TAF SITES AS SMALL CHANCES FOR LIGHT RAIN
BRUSH THE NORTHERN PORTIONS OF THE FORECAST AREA...MAINLY NORTH OF A
DELLS TO PORT WASHINGTON LINE. LIGHT SOUTHWEST WINDS THIS MORNING
WILL INCREASE THROUGH THE LATE MORNING WITH GUSTS BETWEEN 20 AND 25
KNOTS DURING THE AFTERNOON. SURFACE WINDS DECOUPLE THIS EVENING BUT
WINDS ALOFT STAY AROUND 20 TO 25 KTS THROUGH 03Z. VFR CONDITIONS
THROUGH THE FORECAST.


MARINE...

ANOTHER CLOSE CALL FOR A SMALL CRAFT ADVISORY MID TO LATE AFTERNOON
AS DEEP MIXING UP TO 735 MB BRINGS DOWN SWLY WIND GUSTS AROUND 20
KTS...WITH A FEW TO 23 TO 25 KTS NORTH OF MILWAUKEE. FORTUNATELY THE
STRONGEST WINDS ALOFT MOVE ACROSS AFTER 00Z WITH NOCTURNAL COOLING
FURTHER ENHANCING THE OVER-WATER INVERSION PREVENTING FULL MOMENTUM
TRANSFER TO THE SURFACE.

WITH THE OFFSHORE FLOW...THE WATERS IMMEDIATELY ADJACENT TO SHORE
WOULD BE MOST AFFECTED WITH LESSER CHANCES FOR CRITERIA GUSTS TOWARD
OPEN WATER WITH INCREASING STABILITY OVER THE COLD LAKE WATERS.

STRENGTHENING SOUTHERLY WINDS AHEAD OF APPROACHING LOW PRESSURE THAT
CROSSES WI SATURDAY NIGHT BRINGS LIKELIHOOD OF A SMALL CRAFT
ADVISORY SATURDAY.

ANOTHER ADVISORY MAY BE NEEDED SUNDAY NIGHT THROUGH MONDAY...AS
ANOTHER LOW PRESSURE PASSES BY THE SOUTHEAST OF THE AREA. THE TIGHT
PRESSURE GRADIENT SHOULD RESULT IN GUSTY NORTH TO NORTHEAST WINDS
AND HIGH WAVES.

FIRE WEATHER...

NOT A GOOD DAY FOR BURNING AS NEAR-CRITICAL FIRE WEATHER CONDITIONS
RETURN AGAIN TODAY AS DEEP MIXING DROPS DEW POINTS BACK INTO THE
20S...AND POSSIBLY LOWER...WITH GUSTY SOUTHWEST WINDS. HIGH
TEMPERATURES WILL CLIMB INTO THE MIDDLE TO UPPER 60S LEADING TO
MINIMUM RELATIVE HUMIDITY VALUES CLOSE TO AND SLIGHTLY BELOW 20 PCT.
MAIN CONCERN IS FOR GRASS FIRES WITH LITTLE GREEN-UP LEAVING DEAD
DEBRIS AVAILABLE AS FUEL. WILL CONTINUE TO HIGHLIGHT THESE DANGEROUS
CONDITIONS WITHIN THE FIRE WEATHER FORECAST AND HAZARDOUS WEATHER
OUTLOOK.

&&

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

$$
TODAY/TONIGHT AND AVIATION/MARINE...REM
SATURDAY THROUGH THURSDAY...DDV