000
FXUS63 KGRB 050453
AFDGRB

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREEN BAY WI
1053 PM CST TUE MAR 4 2014

UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE

.UPDATE...
ISSUED AT 733 PM CST TUE MAR 4 2014

PERIOD OF CLEAR SKIES AND CALM WINDS WITH FRESH SNOW PLAYING HAVOC
WITH TEMPERATURES THIS EVENING WITH TEMPS FLUCTUATING ABOVE AND
BELOW ZERO AS SEEN AT GREEN BAY. MID CLOUDS APPROACHING FROM THE
WEST AND INCREASING GRADIENT EXPECTED TO LESSEN TREND. TRIED TO
SHOW IN TEMP GRIDS WITH UPDATE.
&&

.SHORT TERM...TONIGHT AND WEDNESDAY
ISSUED AT 233 PM CST TUE MAR 4 2014

LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW THE SHORTWAVE
RESPONSIBLE FOR LAST NIGHTS SNOWS EXITING ACROSS LOWER MICHIGAN
EARLY THIS AFTERNOON.  LAST LITTLE AREA OF FLURRIES IS MOVING INTO
CENTRAL LAKE MICHIGAN OFF THE COAST OF EAST-CENTRAL WISCONSIN...BUT
CLOUDS STRETCH BACK ACROSS CENTRAL WISCONSIN INTO CENTRAL
MINNESOTA.  MEANWHILE...NORTHERN WISCONSIN TEMPORARILY CLEARED OUT
THIS MORNING THOUGH ARE STARTING TO CLOUD UP AGAIN WITH STRATUS
PUSHING IN OFF LAKE SUPERIOR AND MID CLOUDS FLOWING IN AHEAD OF THE
NEXT SYSTEM.  THIS SYSTEM...WITH FORCING FROM WEAK SHORTWAVE ENERGY
AND MID-LEVEL FGEN...IS PRODUCING AN AREA OF SNOW OVER SE NORTH
DAKOTA AND NORTHEAST SOUTH DAKOTA.  THE SNOW IS FOLLOWING THE
MID-LEVEL THERMAL GRADIENT TO THE SOUTHEAST TOWARDS SOUTHERN
MINNESOTA.  FORECAST CONCERNS INCLUDE WHETHER THE NORTHERN EDGE OF
THE SNOW PASSES OVER CENTRAL WISCONSIN...AND THE TEMPERATURES NEXT.

TONIGHT...WEAK SHORTWAVE TROUGH WILL MOVE SE OVER THE NORTHERN
MISSISSIPPI VALLEY.  THE THERMAL GRADIENT WILL TIGHTEN IN RESPONSE
ALONG A MID-LEVEL BAROCLINIC ZONE POSITIONED FROM FAR SOUTHERN
MINNESOTA TO NORTHERN ILLINOIS. MODELS HAVE BECOME MORE BULLISH
IN PRODUCING HIGHER QPF AMOUNTS WITHIN THE BAND OF SNOW...BUT
GENERALLY JUST BRUSH THE NORTHERN EDGE OF THE SNOW ALONG THE
SOUTHERN BORDER OF THE FORECAST AREA. IN ADDITION...A SHORTWAVE
DIGGING SOUTH OVER EASTERN ONTARIO WILL CAUSE A HUDSON BAY HIGH
PRESSURE TO BUILD SOUTH OVER THE NORTHERN GREAT LAKES TONIGHT. LOW
LEVEL WINDS WILL SHIFT TO THE NE THIS EVENING AS THE HIGH SHIFTS
SOUTH...AND ADVECT VERY DRY ARCTIC AIR INTO THE NORTHEAST HALF OF
THE STATE. BECAUSE OF THE DRY AIR...HAVE DOUBTS THAT ANY FLURRIES
OR LIGHT SNOW COULD DEVELOP OVER THE LAKE...ESPECIALLY WITH LAKE
ICE ON THE INCREASE AGAIN. THIS DRY AIR ALSO SUPPORTS KEEPING THE
BAND OF SNOW SOUTHWEST OF THE FORECAST AREA. SO WILL JUST KEEP A
SLIGHT CHANCE OVER WOOD AND WAUSHARA COUNTIES.
OTHERWISE...ANTICIPATE CLEARING SKIES TO OCCUR LATE IN THE EVENING
AND OVERNIGHT FROM NE TO SW WITH THE INFLUX OF ARCTIC AIR. WITH
WINDS EXPECTING TO DROP OFF AFTER MIDNIGHT...HAVE DROPPED TEMPS
OVER N-C AND FAR NE WISCONSIN. STILL THINK TEMPS IN E-C WISCONSIN
WILL HAVE A HARD TIME TANKING DUE TO CLOUDS AND THE NE WINDS.

WEDNESDAY...THE DRY ARCTIC AIR WILL CONTINUE TO ADVECT TO THE
SOUTHWEST INTO CENTRAL WISCONSIN DURING THE MORNING...WHICH SHOULD
LEAD TO CLEARING SKIES.  THE REST OF THE REGION WILL SEE AMPLE
SUNSHINE. LOW LEVEL TEMPS COOL OFF A COUPLE DEGREES COMPARED TO
TODAY...SO SHOULD SEE HIGHS MAINLY IN THE UPPER TEENS WITH A FEW
LOW 20S.

.LONG TERM...WEDNESDAY NIGHT THROUGH TUESDAY
ISSUED AT 233 PM CST TUE MAR 4 2014

THE AREA WILL FINALLY COME OUT OF THE DEEP FREEZE WITH TEMPS
APPROACHING NORMAL VALUES ON FRIDAY...AND LIKELY AGAIN ON
SUNDAY AND/OR MONDAY...THEN A RETURN TO WELL BELOW NORMAL TEMPS IS
EXPECTED (BUT NOT AS COLD AS START OF MARCH). THERE WILL BE A FEW
CHANCES FOR PRECIP ASSOCIATED WITH SHOTS OF WAA...FAST MOVING
SHORTWAVES...A MEANDERING BAROCLINIC ZONE...AND FRONTAL
BOUNDARIES. MAIN FORECAST CONCERNS WILL BE IDENTIFYING THE
"WARMEST" DAYS AND BEST CHANCES FOR PRECIP ASSOCIATED WITH THESE
FEATURES.

HIGH PRESSURE WILL BE SHIFTING INTO THE EASTERN GREAT LAKES
WEDNESDAY NIGHT...PROVIDING FOR A DRY BUT COLD NIGHT FOR MOST
LOCATIONS. THE EXCEPTION COULD BE NEAR LAKE MICHIGAN...WHERE THERE
IS A SMALL CHANCE FOR SOME LAKE EFFECT ACTIVITY. COMBINATION OF
DRY AIR...VEERING WINDS...SLOWLY WARMING TEMPS ALOFT...AND ICE
COVER ON LAKE MICHIGAN WILL LIMIT THE LAKE EFFECT POTENTIAL...SO
ONLY EXPECT SOME CLOUDS AND MAYBE A FEW FLURRIES...BUT PREFER TO
KEEP ANY FLURRY MENTION OUT OF THE FORECAST. ANY ACTIVITY THAT CAN
DEVELOP WILL END AS WINDS TURN SOUTH/SOUTHWEST OVERNIGHT INTO
EARLY THURSDAY MORNING.

WAA BEGINS TO RAMP UP ON THURSDAY...MAINLY ALOFT...AS 850MB TEMPS
ATTEMPT TO FINALLY REACH THE 0C MARK. INCREASING MOISTURE IS ALSO
EXPECTED...WITH SKIES BECOMING MOSTLY CLOUDY BY THURSDAY EVENING.
THURSDAY NOW LOOKS DRY FOR THE AREA...AS MODELS HAVE SLOWED DOWN
THE SYSTEM APPROACHING FROM THE NORTHWEST. WILL ALSO BACK OFF ON
POPS THURSDAY NIGHT FOR CENTRAL AND EAST-CENTRAL WI...BUT KEEP
LIKELY POPS GOING OVER THE NORTH AS THE COLD FRONT AND MID-LEVEL
SHORTWAVE APPROACH.

BEST MOISTURE AND MID/UPPER LEVEL FORCING STAY ACROSS THE NORTH ON
FRIDAY...WITH THE GFS/ECMWF NOT SHOWING MUCH...IF ANY...PRECIP FOR
CENTRAL AND EAST CENTRAL WI. HOWEVER...AS THE COLD FRONT SWINGS
ACROSS THE AREA...FEEL AT LEAST LOW CHANCE POPS ARE NEEDED TO
COVER ANY PRECIP ACTIVITY...ESPECIALLY IN THE MORNING. IF PRECIP
DOES OCCUR...PRECIP TYPE WILL ALSO BE A CONCERN...AS ABOVE 0C AIR
BRIEFLY PUSHES OVER CENTRAL AND EAST-CENTRAL WI. WILL CONTINUE TO
MENTION SLEET AND SNOW AS THE MAIN PRECIP TYPES TO COVER THE MIXED
PRECIP CHANCE. ANOTHER CONCERN WILL BE THE CHANCE FOR DRIZZLE OR
FREEZING DRIZZLE AS THE MID-LEVEL DRY AIR ARRIVES BEFORE THE LOW
LEVEL MOISTURE EXITS. PREFER TO HOLD OFF ON ADDING A CHANCE OF
DRIZZLE AND FREEZING DRIZZLE AT THIS POINT AND ALLOW THE MODELS TO
SHOW A STRONGER SIGNAL. SNOWFALL TOTALS OF AN INCH OR TWO ARE
EXPECTED ACROSS THE FAR NORTH...WITH LOWER TOTALS AS YOU MOVE
SOUTH. TEMPS WILL CLIMB TO NEAR NORMAL ON FRIDAY AHEAD OF THE
FRONT...THEN LOOK FOR CAA TO ALLOW TEMPS TO DROP LATE IN THE
DAY...WITH ANOTHER COLD NIGHT EXPECTED FRIDAY NIGHT.

MAINLY DRY WEATHER WILL PREVAIL ACROSS THE REGION THIS WEEKEND AS
CANADIAN HIGH PRESSURE SETTLES INTO THE PLAINS. MODELS DO SHOW A
FAIRLY POTENT SHORTWAVE PASSING JUST NORTH OF THE AREA SATURDAY
NIGHT...BUT ALL BUT THE GFS KEEP THE AREA DRY AND WILL LEAN TOWARD
THE DRY SOLUTION AND NOT MENTION ANY PRECIP CHANCES. HIGHS MAINLY
IN THE 20S ARE EXPECTED ON SATURDAY...THEN MODELS VARY GREATLY
FOR SUNDAY. ECMWF/GEM WOULD FAVOR HIGHS IN THE 30S TO NEAR
40...WHILE THE GFS HOLDS TEMPS IN THE TEENS. ANOTHER SYSTEM LOOKS
TO BRING PRECIP TO THE AREA ON MONDAY. TEMPS IN THE AFTERNOON LOOK
TO BE WARM ENOUGH TO HAVE SOME RAIN MIX IN WITH THE SNOW...BUT
THERE IS PLENTY OF TIME FOR THIS TO CHANGE.
&&

.AVIATION...FOR 06Z TAF ISSUANCE
ISSUED AT 1040 PM CST TUE MAR 4 2014

A CLIPPER SYSTEM WILL MOVE THROUGH TO THE SOUTHWEST OF THE AREA WHILE
DRY ARCTIC AIR/HIGH PRESSURE WILL PUSH IN FROM THE NORTHEAST
TONIGHT. MID CLOUDS WITH CLIPPER SYSYTEM MOVING OVER MUCH OF THE
AREA. SOME LOWER CLOUDS SEEN FAR NORTHEAST WI...EARLIER MOISTURE
TRAPPED BY INVERSON NOW SPREADING SOUTH AND WEST AS NORTHEAST
FLOW INCREASES. HAVE ADDED CIG TO RHI...THOUGH ONLY GOING
SCATTERED GRB/ATW/MTW. A CHANCE OF FLURRIES WILL EXIST TONIGHT
ALONG THE LAKE SHORE AS WINDS TURN TO THE NORTHEAST
OVERNIGHT...THEN EAST BY LATE WED AFTN...BUT THINKING THE VERY DRY
AIR AND ICE OVER THE LAKE MAKES THE CHANCE VERY SMALL. &&

.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

UPDATE.........TE
SHORT TERM.....MPC
LONG TERM......BERSCH
AVIATION.......TE