Area Forecast Discussion
Issued by NWS Milwaukee/Sullivan, WI

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
024
FXUS63 KMKX 070929
AFDMKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
329 AM CST SUN FEB 7 2016

.TODAY AND TONIGHT...FORECAST CONFIDENCE IS MEDIUM.

NOT MUCH CHANGE TO THE CURRENT FORECAST. THE BIG UPPER LOW BEGINS
TO DIG SOUTHEAST INTO THE GREAT LAKES TODAY...WITH THE ASSOCIATED
SFC LOW MOVING FROM NRN MN TO NRN LOWER MICHIGAN BY SUNRISE
MONDAY. THE WARM AIR ADVECTION OUT AHEAD OF THE LOW HAS SATURATED
THE MID AND UPPER LEVELS...AND LOCAL RADARS ARE ALL SHOWING LIGHT
RETURNS EARLY THIS MORNING...BUT NOTHING REALLY REACHING THE
GROUND. THERE IS A DECENT INTERVENING DRY LAYER.

ONCE THAT WAA MOVES OFF EARLY THIS MORNING...WE DRY OUT THROUGH A
MUCH DEEPER COLUMN...BEFORE WE SATURATE UP AGAIN THIS EVENING.
SO...WILL HANG ONTO SOME SMALL POPS ACROSS THE NORTH UNTIL THE WAA
IS GONE...THEN DRY THROUGH THE DAY WITH SKIES MOSTLY CLOUDY.

THE MAIN COLD FRONT ASSOCIATED WITH THE SFC LOW WILL PUSH INTO
THE AREA PRIMARILY AFTER MIDNIGHT. I/LL BEGIN TO INTRODUCE THE
CHANCE OF LIGHT SNOW IN THE WEST EARLY THIS EVENING...THEN MARCH
IT ACROSS THE CWA...BECOMING LIKELY AFTER MIDNIGHT IN THE WAKE OF
THE FRONT. THERE IS FAIRLY DEEP SATURATION THROUGH THE DENDRITE
ZONE.

.MONDAY THROUGH TUESDAY NIGHT...FORECAST CONFIDENCE IS MEDIUM.

MODELS REMAIN IN PRETTY GOOD AGREEMENT WITH THE MAIN FEATURES
DURING THIS PERIOD ACROSS THE REGION. THEY TAKE THE SURFACE LOW
SLOWLY TO THE EAST SOUTHEAST AWAY FROM THE REGION ON MONDAY...AND
FURTHER TO THE EAST MONDAY NIGHT AND TUESDAY. THE 500 MB LOW
SLOWLY SHIFTS SOUTHEAST OF THE AREA MONDAY INTO TUESDAY. THE NAM
IS THE ONLY MODEL TO KEEP THE LOW ESSENTIALLY STATIONARY OVER
SOUTHWEST LOWER MICHIGAN MONDAY INTO TUESDAY...THOUGH THIS SEEMS
LIKE AN OUTLIER SOLUTION.

SEVERAL VORTICITY MAXIMA ROTATE THROUGH THE AREA MONDAY INTO
TUESDAY...WITH AREA FORECAST SOUNDINGS SHOWING FAIRLY DEEP AND
MOIST LOW TO MID LEVEL PROFILES. THE DENDRITE SNOW CRYSTAL GROWTH
ZONE IS ALSO FAIRLY DEEP DURING THIS TIME.

UPWARD VERTICAL MOTION SHOULD BE STRONG ENOUGH TO KEEP HIGHER END
POPS GOING FOR MONDAY INTO MONDAY NIGHT/TUESDAY. MAY NEED HIGHER
POPS IN LATER FORECASTS IF WET LOOK OF MODELS CONTINUES...ESPECIALLY
IN THE WESTERN PORTIONS OF THE AREA MONDAY NIGHT AND TUESDAY.

GIVEN THE COLDER AIRMASS MOVING INTO THE REGION MONDAY INTO
TUESDAY...THERE SHOULD BE RELATIVELY HIGH SNOW TO LIQUID RATIOS.
THIS SHOULD BRING ON AND OFF LIGHT SNOW SHOWERS...SOME OF WHICH
MAY BE MORE MODERATE IN INTENSITY AT TIMES. A ONE TO TWO INCH SNOW
ACCUMULATION IS EXPECTED MONDAY INTO TUESDAY NIGHT AT THIS
TIME...WITH ACCUMULATION RATES FAIRLY LIGHT.

TEMPERATURES WILL BE BELOW SEASONAL NORMALS...ESPECIALLY TUESDAY
INTO TUESDAY NIGHT. WIND CHILLS SHOULD REACH THE 10 TO 18 BELOW
ZERO RANGE LATER TUESDAY NIGHT.

.WEDNESDAY THROUGH SATURDAY...FORECAST CONFIDENCE IS MEDIUM.

THE ECMWF AND GFS ARE INDICATING THAT NORTHWEST FLOW AT 500 MB
WILL REMAIN OVER THE REGION FOR MOST OF THIS PERIOD...AS A DEEP
500 MB LOW DEVELOPS OVER QUEBEC CANADA. THESE MODELS ARE SHOWING
HIGH PRESSURE SLIDING SOUTHEAST FROM THE NORTHERN PLAINS INTO THE
REGION WEDNESDAY INTO THURSDAY NIGHT...WITH ANOTHER INTO THE
UPCOMING WEEKEND. IT LOOKS TO BE A FAIRLY DRY PERIOD WEDNESDAY
INTO THURSDAY NIGHT...WITH COLD TEMPERATURES LINGERING OVER THE
REGION.

THE ECMWF BRINGS A SWATH OF QPF ACROSS THE NORTHERN PLAINS INTO
IOWA FRIDAY...WHILE THE GFS BRINGS THIS ACROSS WISCONSIN. THESE
WERE BEING DRIVEN BY A SHEARED 500 MB VORTICITY MAXIMUM MOVING
SOUTHEAST THROUGH THESE AREAS. FOR NOW...WILL KEEP THE FORECAST
DRY...GIVEN THE DISAGREEMENT IN THE MODELS. MAY HAVE TO WATCH FOR
LAKE EFFECT SNOW POTENTIAL LATER IN THE WEEKEND...IF HIGH
PRESSURE TO THE NORTH TURNS LOW LEVEL WINDS ONSHORE IN THE
LINGERING COLD AIRMASS. WOULD NEED MORE MOISTURE TO HAVE THIS
OCCUR AS WELL.

&&

.AVIATION/12Z TAFS/...

LOOK FOR VFR CONDITIONS THROUGH THIS MORNING. STRONG SOUTHERLY
WINDS AHEAD OF AN APPROACHING LOW PRESSURE SYSTEM...AND ABOVE THE
BOUNDARY LAYER...WILL RESULT IN LOW LEVEL WIND SHEAR THROUGH ABOUT
MID MORNING. WINDS SHOULD GRADUALLY SETTLE DOWN DOWN BY MID DAY AS
A SFC TROUGH ROTATES IN. THIS IS ACTUALLY THE FIRST...WEAKER COLD
FRONT.

LOW LEVEL RH SHOULD BEGIN TO WRAP IN AROUND THE SFC LOW...IN THE
WAKE OF THIS FIRST TROUGH/COLD FRONT THIS AFTERNOON. AS A
RESULT...WE COULD SEE MVFR CIGS MOVE BACK IN BY EARLY TO MID
AFTERNOON...CONTINUING THROUGH TONIGHT. THERE IS SOME UNCERTAINTY
WITH THIS INITIAL THREAT OF MVFR...AND IT MAY HOLD OFF UNTIL EARLY
THIS EVENING.

A SECOND...MUCH STRONGER...COLD FRONT WILL SWEEP THROUGH TONIGHT
AND THIS WILL BRING INCREASING CHANCES OF LIGHT SNOW. THE BULK OF
ANY LIGHT SNOW WILL OCCUR AFTER MIDNIGHT...CONTINUING THROUGH
MONDAY.

&&

.MARINE...

SOUTHWEST WINDS ARE MARGINAL FOR A SMALL CRAFT ADVISORY THIS
MORNING. THOSE WINDS WILL BE DIMINISHING QUICKLY BY THIS
AFTERNOON. WILL HOLD OFF ON ANY ADVISORY FOR NOW...BUT SMALL CRAFT
SHOULD EXERCISE CAUTION. NORTHWEST WINDS IN THE WAKE OF A LOW
PRESSURE SYSTEM PASSING BY TO THE NORTH WILL LIKELY RESULT IN
SMALL CRAFT ADVISORY CONDITIONS LATER MONDAY AFTERNOON INTO
TUESDAY EVENING.

&&

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

$$

TODAY/TONIGHT AND AVIATION/MARINE...DAVIS
MONDAY THROUGH SATURDAY...WOOD



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.