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000
FXUS63 KARX 161109
AFDARX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LA CROSSE WI
609 AM CDT SUN MAR 16 2014

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 336 AM CDT SUN MAR 16 2014

A COOL DAY IS ON TAP FOR THE REGION AS A RIDGE OF HIGH PRESSURE
DROPS DOWN FROM SOUTHERN CANADA. WITH LOW LEVEL FLOW OUT OF THE
EAST-NORTHEAST...SOME STRATUS HAS BEEN ABLE TO FORM ACROSS
SOUTHERN WISCONSIN. WITH THIS SATURATED LAYER BEING AROUND -10C
THERE HAVE BEEN SOME FLURRIES THAT FORMED. EXPECT THAT AS THE LOW
LEVEL FLOW WEAKENS THIS MORNING/AFTERNOON AS THE RIDGE AXIS MOVES
IN THAT THE DRIER AIR WILL WIN OUT AND CLEAR SKIES OUT...WHICH IS
WHAT THE 16.06Z RAP/NAM RH FIELDS BACK UP AS WELL.

WITH THE 850MB/SURFACE RIDGE IN PLACE ACROSS THE UPPER MISSISSIPPI
RIVER VALLEY TODAY...TEMPERATURES WILL HAVE A HARD TIME CLIMBING
MUCH WITH 850MB TEMPS STAYING AROUND -12C. LOW LEVEL WINDS DO TURN
AROUND TO THE SOUTHWEST TONIGHT AND WILL MARK A GRADUAL WARMING
TREND INTO TUESDAY. THE BETTER FORCING FROM THE WARM AIR ADVECTION
STILL APPEARS TO BE FOCUSED FURTHER TO THE NORTH WITH DRY AIR IN
PLACE AT THE SURFACE/LOW LEVELS. THE 16.00Z NAM/GFS/ECMWF KEEP THE
AREA DRY THROUGH DAY BREAK TOMORROW MORNING WITH ONLY THE 16.00Z
GEM SHOWING ANY LIGHT PRECIPITATION MAKING IT INTO THE REGION.
HAVE KEPT THE FORECAST DRY AS A RESULT.

.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 336 AM CDT SUN MAR 16 2014

THE MAIN FOCUS FOR NEXT WEEK IS WITH THE DEEP SYSTEM THAT WILL
TRACK THROUGH THE REGION ON TUESDAY/WEDNESDAY.

A MID LEVEL TROUGH CURRENTLY ANALYZED OFF THE COAST OF BRITISH
COLUMBIA WILL PROPAGATE EAST ACROSS THE ROCKIES EARLY NEXT WEEK
BEFORE CLOSING OFF AND BECOMING NEGATIVELY TILTED ACROSS THE
DAKOTAS/UPPER MISSISSIPPI RIVER VALLEY REGION TUESDAY INTO
WEDNESDAY. WITH THE SYSTEM STILL OUT OVER THE OCEAN AND NOT BEING
SAMPLED WELL...THERE IS QUITE A BIT OF VARIANCE BETWEEN THE
16.00Z MODELS WITH THE INTENSITY OF THE TROUGH AND WHERE THE
SURFACE LOW TRACKS AS A RESULT OF HOW DEEP THE TROUGH GETS. THE
16.00Z NAM/GFS ARE PRETTY CLOSE TO EACH OTHER WITH SHOWING A
DEEPER/CLOSED OFF MID LEVEL TROUGH ON TUESDAY NIGHT WHILE THE
16.00Z ECMWF/GEM SHOW MORE OF AN OPEN SHORT WAVE THAT STILL GOES
NEGATIVELY TILTED. WITH THE MORE WOUND UP SYSTEM...THE 16.00Z
NAM/GFS SHOW A DEEPER/OCCLUDING SURFACE LOW THAT TRACKS FURTHER
NORTH THAN WHAT THE 16.00Z ECMWF/GEM SHOW. DESPITE THESE
DIFFERENCES...THE NAM/GFS/ECMWF ALL SHOW THAT TUESDAY WILL MAINLY
BE DRY DURING THE DAY WITH THE GEM BEING THE ONLY ONE
PRECIPITATING WITH IT HAVING THE DEFORMATION BAND FROM SOUTHEAST
MINNESOTA INTO NORTH CENTRAL WISCONSIN. HAVE TRENDED TOWARD THE
NAM/GFS/ECMWF AND KEPT TUESDAY MAINLY DRY WITH THE P-TYPE BEING
RAIN SINCE SURFACE TEMPERATURES WILL BE WELL ABOVE FREEZING. THE
CHANCES FOR SLEET/FREEZING RAIN LOOKS VERY LOW WITH SURFACE
TEMPERATURES RISING ABOVE FREEZING BEFORE THE PRECIPITATION
ARRIVES ON TUESDAY...SO HAVE REMOVED THAT FROM THE FORECAST.

THE TRICKY PART OF THE FORECAST IS ON TUESDAY NIGHT INTO WEDNESDAY
MORNING AS THE TROUGH/SURFACE LOW COME THROUGH AND HOW THE
PRECIPITATION TYPE TRANSITIONS. 16.00Z NAM/GFS SOUNDINGS SHOW THAT
THE RAIN WILL CHANGE OVER TO SNOW FOR A PERIOD TUESDAY NIGHT WITH
SOME ACCUMULATION EXPECTED BEFORE THE COLD AIR ADVECTION GETS IN
EARLY ON WEDNESDAY. 16.03Z SREF PLUMES SHOW A FAIRLY TIGHT RANGE
WITH MOST OF THE MEMBERS BETWEEN A HALF INCH TO TWO INCHES OF
ACCUMULATION BUT THE GEM WILL HAVE TO BE WATCHED AS IT WOULD BE A
MUCH SNOWIER SOLUTION.

THE OTHER PART TO THIS SYSTEM COMES INTO PLAY ON WEDNESDAY WITH
HOW STRONG WINDS WILL BE. THE OCCLUDING SURFACE LOW SHOWN VIA THE
NAM/GFS WOULD SUGGEST SOME SUSTAINED WINDS BETWEEN 20-30MPH AND
SOME GUSTS GETTING INTO THE 35-45MPH RANGE WITH THE WEAKER
ECMWF/GEM KNOCKING ABOUT 10MPH OFF OF THOSE SPEEDS. SHOULD THE
NAM/GFS BE THE RIGHT TREND...A WIND ADVISORY WILL HAVE TO BE
CONSIDERED DOWN THE ROAD.

THE ACTIVE PATTERN CONTINUES LATER IN THE WEEK AS ANOTHER TROUGH
DIVES DOWN AND BRINGS A SURFACE LOW THROUGH TO THE SOUTH OF THE
REGION. NOT A LOT OF CONSISTENCY BETWEEN THE GUIDANCE ON THIS
FEATURE...BUT THE ECMWF SHOWS A FAIRLY DECENT WAVE THAT WOULD
BRING SOME ACCUMULATING SNOWS.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 609 AM CDT SUN MAR 16 2014

NORTHEAST WIND ACROSS THE OPEN WATERS OF LAKE MICHIGAN DREW SOME
MVFR STRATOCUMULUS INTO/ACROSS SOUTHERN WI...SOME OF WHICH MADE IT
INTO KLSE AROUND 09Z. SINCE THEN THIS CLOUD HAS SCATTERED
OUT/DISSIPATED. HIGH PRESSURE OVER NORTHERN MN/WI EARLY THIS
MORNING WILL CONTINUE TO BUILD SOUTHEAST INTO THE WESTERN GREAT
LAKES REGION TODAY FOR VFR/MOSTLY CLEAR SKIES. LOW PRESSURE AND A
WARM FRONT WILL MOVE INTO THE NORTHERN PLAINS TONIGHT...SPREADING
MID-LEVEL CLOUD WITH BASES IN THE 5-8KFT RANGE INTO THE KRST BY
06Z AND KLSE BY 09Z. OTHERWISE...LOOK FOR INCREASING SOUTH SURFACE
WINDS OVERNIGHT...ESPECIALLY AT KRST AFTER 06Z.

&&

.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&

$$

SHORT TERM...HALBACH
LONG TERM...HALBACH
AVIATION...DAS