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000
FXUS63 KGRB 100554 AAC
AFDGRB

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE GREEN BAY WI
1154 PM CST TUE FEB 9 2010

.UPDATE...REMOVED MORE OF EC WI FROM THE HEADLINES.

TDH
&&

.PREV DISCUSSION...ISSUED AT 1001 PM CST TUE FEB 9 2010...

UPDATE...SENT UPDATED HEADLINES AND ZONES OUT A FEW MINUTES AGO.

TDH


DISCUSSION ISSUED AT 847 PM CST TUE FEB 9 2010...

UPDATE...RADAR SHOW SNOW WINDING DOWN OVER CENTRAL WI...WITH WIND
GUSTS AROUND 20.  WILL TRY TO CANCEL CENTRAL WI BY 9 PM ALL AT
ONCE BUT RADAR SHOW A FEW BANDS OF SNOW HANGING OVER SHAWANO...WAUPACA
AND WAUSHARA. IF SNOW BANDS PERSIST WILL REMOVE WOOD AND PORTAGE
FIRST AND THEN GET THE NEXT TIER LATER EVENING.

RADAR SHOWS A LES BAND JUST BRUSHING FAR EAST MTW COUNTY EARLY
THIS EVENING...BUT APPEARS WINDS ARE STARTING TO TURN TOO NNE AND
PUSHED THIS BAND OFF SHORE AND AS A RESULT WILL PUSH THE STRONGER
LES ACTIVITY TWD SE WI AND NE IL.

OVERALL PLAN THIS EVENING WILL BE TO REMOVE HEADLINES WEST OF A
LINE FROM GRB TO OSH...BUT KEEP SOME KIND OF HEADLINE GOING POINTS EAST
DUE TO SNOW AND BLOWING SNOW. JUST NOT SURE WE CAN QUITE DO THIS
BEFORE THE 10 PM BROADCASTS.

TDH


DISCUSSION ISSUED AT 256 PM CST TUE FEB 9 2010...

SHORT TERM...TNGT AND WED. MAIN FCST CONCERN REMAINS EXTENT OF
ACCUMULATING SNOW AND STRENGTH OF THE WNDS AS THE WINTER STORM
BEGINS TO PULL AWAY TNGT.

THE 20Z MSAS SFC ANALYSIS SHOWED LOW PRES LOCATED OVR W-CNTRL OH
WITH HI PRES EXTENDED FROM THE NRN PLAINS NEWD INTO NRN ONTARIO.
THE PRES GRAD BETWEEN THESE TWO FEATURES WAS GENERATING GUSTY N-NE
WNDS ACROSS WI THIS AFTERNOON WHICH WAS CREATING PLENTY OF BLOWING
AND DRIFTING SNOW. RADAR MOSAIC PAINTED SNOW OVER ALL BUT FAR NW
WI WITH THE HEAVIEST SNOWS OCCURRING FROM KEWAUNEE SWD THRU MKE.

THE 5H UPR LOW IS FCST TO QUICKLY MOV EAST FROM E-CNTRL IL ALL THE
WAY TO WEST VA BY DAYBREAK. COMBINATION OF CYCLONIC FLOW AND CAA
WL KEEP THE SNOW GOING AT LEAST THRU THE EVENING HRS BEFORE ENDING
FROM WEST TO EAST. ANOTHER INCH OR TWO OF ACCUMULATION IS PSBL OVR
E-CNTRL (PERHAPS 2-3 INCHES FOR MANITOWOC) WITH LESSER AMTS
FARTHER NORTH AND WEST. EVEN WITH THE SNOW GRADUALLY TAPERING
OFF...THE WNDS ARE EXPECTED TO REMAIN QUITE BLUSTERY WHICH WL KEEP
THE BLOWING/DRIFTING SNOW AROUND THRU THE NGT. AFT COLLABORATION
WITH ARX...HAVE DECIDED TO EXTEND THE WINTER WEATHER ADVY FOR
CNTRL WI TIL MIDNGT. DUE TO THE LATE NATURE OF THE SNOW COMING TO
AN END OVR THE EAST...HAVE ALSO EXTENDED THE ADVY AND WARNING IN
THE EAST TIL 12Z. THE OTHER ASPECT THAT NEEDS TO BE WATCHED LTR
TNGT WL BE LK EFFECT DEVELOPMENT OFF OF LK SUPERIOR AS WNDS BACK
MORE NORTH. TRAJS ARE NOT IDEAL FOR VILAS CNTY AND DELTA-T VALUES
ARE ONLY IN THE LWR TEENS. THEREFORE...DO NOT SEE MUCH SNOW SHWR
THREAT TNGT IN THE NORTH. AIRMASS BEHIND THIS STORM IS NOT OVERLY
COLD AND WITH CLDS AROUND THRU THE NGT...HAVE NUDGED MIN TEMPS UP
A COUPLE OF DEGS.

CYCLONIC FLOW TO GRADUALLY DIMINISH ON WED EVEN AS A SFC TROF
LINGERS NW-SE OVR THE GREAT LKS. WNDS TO BE MORE N-NW ON WED WHICH
DOES FAVOR BRINGING SNOW SHWRS INTO N-CNTRL WI. HOWEVER...SNOW
AMTS WL AGAIN BE LIMITED BY A LACK OF COLD AIR ALOFT AND MODEST
LOW-LVL INVERSIONS. SOME LATE DAY CLEARING IS PSBL OVR CNTRL WI AS
HI PRES BEGINS TO BUILD EAST FROM THE UPR MIDWEST. MAX TEMPS TO BE
LIMITED BY THE COOL N-NW WNDS AND COOLER AIRMASS...THUS EXPECT MAX
TEMPS ONLY IN THE LWR TO MID 20S FOR WED.

LONG TERM...WEDNESDAY NIGHT THROUGH TUESDAY. MAIN CONCERNS REMAIN
LAKE EFFECT POTENTIAL AND TIMING SHORTWAVES LATER THIS WEEK AND
WEEKEND.

LAKE EFFECT SNOW ISSUES WILL START OFF THE LONG TERM...WITH
NORTH/NORTHWEST FLOW CONTINUING WEDNESDAY NIGHT. DELTA T/S STILL
NOT OVERLY IMPRESSIVE...SO WILL CONTINUE TO HOLD ON TO CHANCE POPS
ACROSS FAR NORTH CENTRAL WI...BUT ONLY MENTION MINOR
ACCUMULATIONS. WINDS WILL BACK TO THE WEST BY THURSDAY
MORNING AS RIDGING BUILDS IN...SHUTTING OF ANY ACTIVITY FROM
OVERNIGHT. WEAK HIGH PRESSURE BUILDS IN FOR THURSDAY...KEEPING US
DRY. TEMPS SHOULD REMAIN SLIGHTLY BELOW NORMAL.

MODELS STILL NOT COMPLETELY IN AGREEMENT FOR THE FRIDAY/SATURDAY
SYSTEMS. CANADIAN/GFS/ECMWF ALL SHOW TWO SHORTWAVES DROPPING DOWN
FROM MANITOBA. THE FIRST WEAK ONE WILL CROSS THE WESTERN GREAT
LAKES AREA FRIDAY...THEN A STRONGER SHORTWAVE WILL FOLLOW.
CANADIAN IS SLOWEST WITH THE SECOND SHORTWAVE...KEEPING IT IN
CANADA INTO SATURDAY MORNING...WHILE THE ECMWF IS THE FASTEST
PLACING IT ACROSS SOUTHEAST MINNESOTA. GFS IS MUCH CLOSER TO THE
CANADIAN. THESE DIFFERENCES WILL AFFECT WHEN THE BEST CHANCE FOR
ANY PRECIP WILL OCCUR. WITH NO REAL CONFIDENCE...DO NOT PLAN ANY
MAJOR CHANGES TO THE GOING FORECAST. PLAN TO USE A BLEND OF THE
GFS/CANADIAN/ECMWF...AS NO MODEL IS PREFERRED AT THIS POINT. WILL
KEEP JUST SLIGHT CHANCES FOR LIGHT SNOW AND FLURRIES FOR FRIDAY
NIGHT THROUGH SATURDAY NIGHT FOR MOST...BUT INCREASE POPS SLIGHTLY
ACROSS THE SOUTHERN CWA ON SATURDAY. ONCE TIMING BECOMES A LITTLE
CLEARER...CHANCE POPS WILL PROBABLY NEED TO BE ADDED/EXPANDED.

WILL CONTINUE WITH A DRY FORECAST FOR SUNDAY INTO TUESDAY...AS
MODELS SHOW SHORTWAVE DIVING INTO THE OHIO VALLEY...KEEPING THE
PRECIP SOUTHEAST OF THE AREA. MODELS DO SHOW ANOTHER UPPER LOW
SPINNING ACROSS EASTERN CANADA...BUT THEY KEEP THE ASSOCIATED
PRECIP JUST TO OUR EAST. WITH CONTINUED NORTH/NORTHWEST WINDS
THROUGH THIS PERIOD...LAKE EFFECT WILL BE POSSIBLE. CURRENT
THINKING IS THIS ACTIVITY WILL STAY ACROSS THE U.P.

AVIATION...WIDESPREAD MVFR CONDITIONS EXPECTED TONIGHT INTO WED
MORNING DUE TO SNOW AND/OR BLOWING SNOW. AS STORM BEGINS TO PULL
AWAY WED MORNING...LOOK FOR CIGS/VSBYS TO RETURN TO VFR
CONDITIONS. GUSTY NE WNDS WL BACK NORTH TNGT AND N-NW ON WED.

MARINE...GALE WARNING IN EFFECT TONIGHT AND WED MORNING PERIOD.
LIKELY BE MARGINAL GALE AS SHEAR IN LLVL WINDS TOO GREAT...BUT
SFC WND DIRECTION IDEAL FOR FUNNELING THROUGH DEATHS DOOR AND FOR
GOOD CONVERGENCE ALONG LAKE MI COAST.
&&

.GRB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 3 AM CST WEDNESDAY FOR WIZ022-040-
050.

&&

$$