FXUS63 KGRB 071024
AFDGRB

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREEN BAY WI
424 AM CST MON DEC 7 2009

.SHORT TERM...TODAY THROUGH TUESDAY.

FORECAST FOCUS IS ON SNOW.

EARLIER UPDATE TO CURRENT ADVISORY/SNOW TOTALS CONTINUED. SFC LOW
AT 9Z OVER NORTHEAST MO. PRESSURE FALLS SUGGEST SYSTEM TO PASS
SOUTH OF CHICAGO. AREA RADARS SHOWING BACKEDGE OF LIGHT SNOW NOW
MOVING INTO SOUTHWEST WI WITH HIGHER REFLECTIVITY'S EXTENDING
SOUTHWEST FROM SHEBOYGAN. SURFACE WINDS SHOWING SIG CONVERGENCE
ALONG LAKESHORE ASSOCIATED WITH THESE HIGHER REFLECTIVITY'S. THIS
AREA WILL LIKELY CLIP FAR SOUTHEAST MANITOWOC. LOWER VISBYS ALSO
SEEN FLD TO ATW WITH WEB CAMS SHOWING ROADS BECOMING SNOW COVERED.
DRY AIR TO THE NORTH WITH DEW POINTS IN THE SINGLE DIGITS LIMITING
NORTHWARD EXTENT WITH ONLY DUSTING SO FAR IN GRB. SNOW WILL EXIT
BY NOON ALL AREAS.

LAKE EFFECT POTENTIAL OVER FAR NORTH CENTRAL WI LIMITED WITH LIGHT
WIND REGIME KEEPING THINGS CONFINED CLOSE TO THE LAKE. 

ATTENTION SHIFTS TO NEXT WINTER STORM. HAVE BUMPED POPS UP
BRINGING IN PCPN EARLIER TUE WITH WAA REGIME AND DIVERGENT FLOW
ALOFT. MAIN EFFECTS TUE NIGHT...COVERED BY LONG TERM.

.LONG TERM...TUE NGT THRU NXT SUNDAY. OBVIOUS MAIN FOCUS FOR THIS
PART OF THE FCST CENTERS AROUND THE FIRST SIGNIFICANT SNOWSTORM OF 
THE SEASON DURING THE TUE NGT THRU WED NGT TIME FRAME. MORE
TRANQUIL WEATHER COMES LATER IN THE WEEK ACCOMPANIED BY RATHER
COLD TEMPERATURES.

FIRST MAJOR STORM OF THE WINTER SEASON WL BE BEARING DOWN ON THE
GREAT LKS TUE NGT AS AN INTENSIFYING AREA OF LOW PRES IS FCST TO
MOV FROM THE SRN PLAINS NEWD TO NEAR SOUTH BEND INDIANA BY 12Z
WED. SEVERAL WEATHER PARAMETERS COMING TOGETHER FOR HVY SNOW
ACROSS NE WI. FIRST...THE CURRENT STORM TRACK PLACES THE SE HALF
OF THE FCST AREA IN A PRIME LOCATION FOR HVY SNOW. SECOND...STG
ISEN LIFT ALONG THE 285K SFC WITH LOW-LVL MSTR GETTING WRAPPED/
THROWN BACK INTO WI. THIRD...VERY STG Q-G FORCING SIGNAL IN THE
MID-LVLS OF THE ATM ALONG WITH A MODEST FRONTOGENETICAL FORCING
CENTERED OVR E-CNTRL WI BETWEEN 06Z AND 12Z WED. FOURTH...NE WI TO
RESIDE IN A FAVORED COUPLED JET STRUCTURE WITH STG LIFT OVR ALL
BUT N-CNTRL WI. FINALLY...ENUF LOW-LVL MSTR TO BE IN PLACE (AT
LEAST 3 G/KG) FOR THE STORM TO USE. IN ADDITION TO THE SNOW...
INCREASING NE WNDS (BACKING TO NORTH LATE) WL ADD SOME LK
ENHANCEMENT TO THE SNOW TOTALS NEAR LK MI. THESE WNDS ARE FCST TO
REACH 10 TO 20 MPH N-CNTRL WI...TO 20 TO 30 MPH SUSTAINED NEAR LK
MI BY WED MORNING WHICH WOULD CREATE PLENTY OF BLOWING/DRIFTING
SNOW WITH REDUCED VSBYS. NEEDLESS TO SAY...TRAVEL CONDITIONS ARE
EXPECTED TO BECOME VERY HAZARDOUS BY THE TIME THE MORNING COMMUTE
STARTS ON WED WITH NEAR WHITE-OUT CONDITIONS (ESP FOR E-CNTRL WI).
CONDITIONS WL NOT IMPROVE THRU THE THE DAY ON WED AS THE STORM
MOVS NE INTO LK HURON BY 00Z THU. THE HEAVIER SNOW ACCUMULATIONS
PROBABLY WL BE BEGIN TO TAPER OFF LATE WED MORNING...HOWEVER
BLUSTERY N-NW WNDS ARE EXPECTED TO CONT PRODUCING AREAS OF
BLOWING/DRIFTING SNOW. HAVE DECIDED TO LET THE CURRENT HEADLINES
STAND UNTIL THE INITIAL SYSTEM DEPARTS AND FULL FOCUS TO THEN BE
ON THE IMPENDING STORM. WINTER STORM WARNINGS ARE LIKELY TO BE
ISSUED LTR TDA AS TOTAL ACCUMULATIONS BY WED EVENING COULD RANGE
FROM 6 TO 8" NORTH...TO 8 TO 12" SOUTH. 

STORM HEADS INTO QUEBEC WED NGT AND EXPECT ACCUMULATING SNOW TO
QUICKLY COME TO AN END DURING THE EVENING HRS. HOWEVER...BLUSTERY
CONDITIONS ARE EXPECTED TO PERSIST THRU THE EVENING BEFORE
GRADUALLY DIMINISHING INTO THE 10 TO 15 MPH RANGE BY THU MORNING.
NOT TOO WORRIED ABT LK EFFECT POTENTIAL FOR NRN WI AS WNDS TO BACK
MORE WESTERLY OVRNGT...THUS KEEPING THE BETTER SNOW BANDS NORTH OF
THE MI BORDER. PERHAPS A COUPLE OF INCHES ARE PSBL ACROSS NW
SECTIONS OF VILAS CNTY WITH LESSER AMTS FARTHER SOUTH AND EAST.
THE GREAT LKS RGN TO THEN RESIDE ON THE SRN EDGE OF A VERY COLD
BROAD UPR TROF CENTERED OVER CNTRL CANADA. 8H TEMPS CRASH TO
AROUND -22C ON THU...THUS HARD TO SEE HOW TEMPS CAN WARM MUCH
DURING THE DAY. IN FACT...PARTS OF NRN WI MAY NOT GET OUT OF THE
SINGLE DIGITS ON THU FOR MAX TEMPS.

HI PRES IS FCST TO DOMINATE THE ERN HALF OF THE CONUS BY FRI WHICH
SHOULD BRING PARTLY CLDY SKIES AND LIGHTER WNDS TO WI. EXPECT TO
SEE RATHER CHILLY CONDITIONS OVR NE WI THU NGT WITH FRESH SNOWPACK
ALLOWING ANY LIMITED WARMTH TO EXIT INTO SPACE. HAVE LOWERED MIN
TEMPS A FEW DEGS WITH SUB-ZERO READINGS NORTH...DOWN TO AROUND 5
ABOVE NEAR LK MI. NOT MUCH OF A REBOUND EITHER ON FRI WITH MAX
TEMPS STRUGGLING TO GET INTO THE MID TEENS AT BEST.

AS THE CORE OF THE HI PRES SHIFTS TOWARD THE MID-ATLANTIC STATES
FRI NGT...WNDS WOULD BACK SW TOWARD SAT MORNING. STILL A VERY COLD
NGT ON TAP FRI NGT BEFORE WEAK WAA ARRIVES ON SAT. SOME MDLS HINT
THAT A WEAK FNTL BNDRY WL PASS THRU THE RGN LTR SAT/SAT NGT...BUT
MSTR MAY BE AN ISSUE SO HAVE KEPT THE WEEKEND DRY FOR NOW.
&&

.AVIATION...MAINLY VFR CONDITIONS NORTH...WITH MVFR/IFR CIGS VSBY
IN SNOW OVER SOUTH CENTRAL AND EAST CENTRAL WI. LOOK FOR
IMPROVING CONDITIONS BY NOON OVER FOX VALLEY AND LAKESHORE. SIG
WINTER STORM TO AFFECT AREA TUE...WITH DETERIORATING CONDITIONS
THROUGH TUE...NEAR BLIZZARD CONDITIONS TUE NIGHT/WED MORN.
&&

.MARINE...A PROLONGED PERIOD OF GALE FORCE WNDS ARE PSBL LATE TUE
NGT THROUGH THU ASSOCIATED WITH THE WINTER STORM MOVG THRU THE
RGN.
&&

.GRB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL NOON CST TODAY FOR WIZ040-048>050.

WINTER STORM WATCH FROM TUESDAY EVENING THROUGH WEDNESDAY 
EVENING FOR WIZ005-010>013-018>022-030-031-035>040-045-048>050-
073-074.

&&

$$
TE/AK