000
FXUS63 KMKX 131616
AFDMKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
1116 AM CDT SUN APR 13 2014

.UPDATE...ADDED REST OF SOUTHERN WISCONSIN TO FLOOD WATCH. DETAILS
IN HYDRO SECTION BELOW. DENSE FOG THAT WAS PLAGUING PARTS OF
SOUTHERN WI HAVE IMPROVED FOR THE MOST PART. RAIN CONTINUES TO
SURGE TOWARDS SRN WI FROM IA AND NRN IL.

PC

&&

.AVIATION/18Z TAFS/...LOW PRESSURE WILL TRACK FROM THE CENTRAL
PLAINS TO EASTERN LOWER MI BY MONDAY MORNING. MODERATE TO HEAVY
RAIN WILL BE WIDESPREAD ACROSS SRN WI WITH THIS TRACK. INITIAL
MOISUTRE SURGE AHEAD OF THE LOW SPREADS RAIN IN THIS AFTERNOON.
IFR AND SOME LIFR CIGS WILL BE PREVALENT TODAY AND TONIGHT. WITH
COLDER AIR WRAPPING INTO THE SYSTEM LATER TONIGHT...EXPECTING A
MIX AND CHANGEOVER TO OCCUR WHICH WILL RESULT IN SOME LIGHT
ACCUMULATIONS...ESPECIALLY NORTHWEST OF KUES AND NORTH OF KMSN.
GUSTY NNE WINDS WILL TRANSITION TO MORE OF NNW WIND FOR MONDAY AND
REMAIN BLUSTERY.

PC

&&

.HYDROLOGY...HEAVY RAINFALL FELL NORTH OF A PORT WASHINGTON TO
SUN PRAIRIE TO MINERAL POINT LINE WHERE TO 2 4 INCHES OF RAIN FELL
YESTERDAY AFTERNOON AND LAST NIGHT.

LOW PRESSURE WILL MOVE NORTHEAST ALONG A FRONTAL BOUNDARY JUST TO
THE SOUTH OF WISCONSIN.  THE LOW WILL REACH NORTHERN ILLINOIS BY
MIDNIGHT AND INTO LOWER MICHIGAN DURING THE EARLY MORNING HOURS.  AN
ADDITIONAL 1 TO 2 INCHES OF RAINFALL IS EXPECTED IN THE AREA THAT
RECEIVED THE HEAVY RAIN LAST NIGHT.  WIDESPREAD 2 INCH TOTALS ARE
EXPECTED OVER SOUTH AREAS INCLUDING MADISON...MILWAUKEE...RACINE AND
KENOSHA.

IF THIS ADDED RAIN MATERIALIZES...IT WILL SEND MANY RIVERS INTO
FLOOD.  SOME RIVERS MAY EVEN REACH MAJOR FLOOD CATEGORY...LIKE THE
SHEBOYGAN RIVER...AND MILWAUKEE RIVER AT CEEDARBURG.

FLOOD WATCHES ARE IN EFFECT INTO MONDAY MORNING.

HENTZ

&&

.PREV DISCUSSION... /ISSUED 340 AM CDT SUN APR 13 2014/

TODAY AND TONIGHT...FORECAST CONFIDENCE IS HIGH.

THE ACTIVE SOUTHWEST MID LEVEL FLOW WILL CONTINUE INTO MONDAY
MORNING...FOLLOWED BY THE PASSAGE OF A LARGER TROF THAT WILL BRING A
PATTERN CHANGE FOR MUCH OF THE REMAINING WEEK AHEAD. THE CONVECTION
EARLY THIS MORNING IS DIMINISHING AND MAY END COMPLETELY FOR A TIME
AS A MID LEVEL SHORT WAVE EXITS TO THE NORTHEAST.  ANOTHER ROUND OF
RAIN WILL ARRIVE BY EARLY AFTERNOON AS ANOTHER STRONG SHORT WAVE
RIDES INTO THE AREA RESULTING IN RAPID SFC CYCLOGENESIS OVER THE MID
MS VALLEY. THE SFC LOW AND ITS WARM FRONT WILL REMAIN SOUTH OF THE
AREA...BUT THE H8 WARM FRONT AND BAROCLINIC ZONE WILL BE STRETCHED
FROM NORTHEAST WI BACK INTO THE SOUTHWEST CORNER OF THE STATE.
THERE IS AN IMPRESSIVE RIGHT ENTRANCE REGION TO THE UPPER JET
LOCATED OVER THE AREA RESULTING IN A STRONG ISENTROPIC LIFT RESPONSE
ACROSS THAT THERMAL GRADIENT. THE LOW LEVEL JET WILL CONTINUE TO
SUPPLY AMPLE MOISTURE WITH PRECIPITABLE WATER VALUES HOLDING IN THE
1 TO 1.4 INCH RANGE.  QUITE HIGH FOR THIS TIME OF YEAR.  AREAS
ACROSS THE NORTHERN FORECAST AREA RECEIVED ABOUT 2 TO 3 INCHES OF
RAIN ALREADY...AND THAT AREA COULD GET ANOTHER 1 TO POSSIBLY 2
INCHES LATER TODAY AND TONIGHT. WILL THEREFORE ISSUE AN AREAL FLOOD
WATCH FOR THE AREA THAT GOT HIT THE HARDEST YESTERDAY AND OVERNIGHT.

ANY THUNDER SHOULD BE LIMITED TO THE SOUTHERN OR SOUTHEAST FORECAST
AREA INTO THIS EVENING. INSTABILITY IS VERY LIMITED AND SEVERE
WEATHER...APART FROM ANY FLOODING...IS NOT EXPECTED.

SURFACE TEMPS WILL REMAIN VERY CHILLY...ESPECIALLY ACROSS THE EAST
AS NORTHEAST WINDS WILL RULE WITH THE WARM FRONT STAYING TO THE
SOUTH OF THE BORDER.

AS THE SURFACE LOW PULLS OFF TO THE EAST TONIGHT...COLDER AIR WILL
FILTER SOUTH LIKELY CAUSING THE WEST EDGE OF THE PRECIP SHIELD TO
TRANSITION OVER TO RAIN/SNOW THEN ALL SNOW BEFORE ENDING. THIS
TRANSITION WILL SPREAD FROM WEST TO EAST BETWEEN 06-12Z MONDAY.  ANY
ACCUMS WILL REMAIN AT OR BELOW 1 INCH.  THE GROUND SHOULD BE PRETTY
WARM WITH MOST ACCUMS LIMITED TO GRASSY AREAS.

MONDAY AND TUESDAY...FORECAST CONFIDENCE...HIGH

WILL SEE SOME LIGHT SNOW CONTINUE MONDAY MORNING. SHOULD BE MAINLY
DRY FROM MID OR LATE MORNING AND INTO THE AFTERNOON...WITH MODELS
SUGGESTING A LITTLE MORE LIGHT SNOW TO SLIDE INTO EASTERN FORECAST
AREA LATE AFTERNOON AND EVENING. ANY ACCUMULATIONS SHOULD BE
UNDER AN INCH. IT WILL BE CHILLY MONDAY...WITH HIGHS ONLY TOPPING
OUT IN THE UPPER 30S TO AROUND 40. LOWS MONDAY NIGHT WILL THEN
DROP INTO THE 20S.

IT SHOULD BE DRY TUESDAY AS HIGH PRESSURE SLIDES THROUGH. THOUGH
TEMPS ALOFT WILL BE WARM ADVECTING THROUGH THE DAY...THE COLDEST
AIRMASS WILL BE OVERHEAD AT DAYBREAK. AFTERNOON HIGHS ARE THUS
EXPECTED TO STRUGGLE ONCE AGAIN INTO THE UPPER 30S AND LOW 40S.

WEDNESDAY THROUGH SATURDAY...FORECAST CONFIDENCE...LOW

THERE IS QUITE A BIT OF UNCERTAINTY AMONG MODELS FOR WEDNESDAY INTO
NEXT WEEKEND. THERE WILL BE PRECIP CHANCES MAINLY IN THE NORTH
WEDNESDAY. LOOKS LIKE PRECIP SHOULD BE RAIN...THOUGH A LITTLE MIX
WITH SNOW IS POSSIBLE EARLY IN THE MORNING. SHOULD SEE MILDER
TEMPS...UP TO THE LOW 50S EXCEPT FOR IN THE EAST.

USED MAINLY A CONSENSUS APPROACH FOR THE THURSDAY-SATURDAY
FORECAST...DUE TO THE LARGE MODEL DIFFERENCES IN STORM
TRACK...TEMPERATURES...AND RESULTANT PRECIP TYPE. FOR
INSTANCE...GFS HAS A GOOD AMOUNT OF ACCUMULATING SNOW WEST ON
FRIDAY...WHILE THE ECMWF HAS HIGHS AROUND 50. GFS HAS A FEW LIGHT
SNOW SHOWERS WITH HIGHS IN THE 30S SATURDAY...WHILE THE ECMWF IS
AROUND 60 WITH DRY WEATHER. NEEDLESS TO SAY...VERY LITTLE
CONFIDENCE IN THE EXTENDED FORECAST.

AVIATION/12Z TAFS/...EXPECT IFR CIGS THROUGH MUCH OF THE ENTIRE TAF
PERIOD AS A COOL NORTHEAST TO EAST FLOW INTERACTS WITH AMPLE
MOISTURE LINGERING OVER THE AREA.  THE PRECIP WILL DIMINISH OR END
FOR A TIME THIS MORNING BEFORE MORE RAIN...SOME HEAVY AT
TIMES...ARRIVES THIS AFTERNOON AND CONTINUES THROUGH TONIGHT.  THE
RAIN WILL LIKELY TRANSITION OVER TO SOME SNOW IN THE MADISON AREA BY
AROUND 09Z MON BEFORE ENDING. PAVEMENT TEMPERATURES WILL LIKELY BE
TOO WARM FOR ANY APPRECIABLE ACCUMULATIONS. ANY ACCUMS WOULD BE LESS
THAN AN INCH.


MARINE...A SMALL CRAFT ADVISORY IS IN EFFECT FOR TONIGHT THROUGH
MONDAY DUE TO BRISK NORTHERLY WINDS IN THE WAKE OF A DEPARTING LOW
PRESSURE SYSTEM.

&&

.MKX WATCHES/WARNINGS/ADVISORIES...
WI...FLOOD WATCH FROM 7 PM CDT THIS EVENING THROUGH MONDAY MORNING
     FOR WIZ063>072.

     FLOOD WATCH THROUGH MONDAY MORNING FOR WIZ046-047-051-052-
     056>060-062.

LM...SMALL CRAFT ADVISORY FROM 7 PM THIS EVENING TO 7 PM CDT MONDAY
     FOR LMZ643>646.

&&

$$
TODAY/TONIGHT AND AVIATION/MARINE...DAVIS
MONDAY THROUGH SATURDAY...DDV