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000
FXUS63 KGRB 060926
AFDGRB

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREEN BAY WI
326 AM CST FRI DEC 6 2013

FORECAST DISCUSSION FOR ROUTINE MORNING FORECAST ISSUANCE

.SHORT TERM...TODAY...TONIGHT...AND SATURDAY
ISSUED AT 326 AM CST FRI DEC 6 2013

VERY COLD CONDITIONS TO CONTINUE THIS PERIOD. WITH CURRENT
HEADLINE CONDITIONS A LITTLE SLOW TO MEET CRITERIA THIS
MORNING...AS CLOUDS LINGERED LONGER INTO THE LATE EVENING...THOUGH
WIND CHILLS CURRENTLY -20 AT MANITOWISH WATERS...EAGLE RIVER AND
ANTIGO...-24 AT RHINELANDER. NO CHANGE TO CURRENT HEADLINE.

MORE COLD AIR FILTERS IN TODAY BEHIND WAVE MOVING TO THE OF THE
STATE. GRADIENT BETWEEN HIGH PRESSURE IN PLAINS AND LOW TO THE
NORTH WEAKENS SOME...BUT EXPECT WIND TO REMAIN UP THROUGH TODAY
INTO TONIGHT TO MAKE WIND CHILL A CONCERN ONCE AGAIN. WILL NOT
ISSUE NEW HEADLINE TIL CURRENT ONE ENDS.

HIGH PRESSURE MOVES INTO STATE ON SAT. MAX TEMPS ON FRI AND SAT TO
REMAIN SOME 20 DEGREES BELOW CLIMATIC NORMALS.

.LONG TERM...SATURDAY NIGHT THROUGH THURSDAY
ISSUED AT 326 AM CST FRI DEC 6 2013

THE HIGHLY AMPLIFIED MEAN FLOW CONSISTING OF AN ERN PACIFIC UPR
RDG...CNTRL CONUS LONGWAVE TROF AND WRN ATLANTIC UPR RDG TO
PERSIST INTO EARLY NEXT WEEK BEFORE SIGNS DEVELOP THAT THE ERN
PACIFIC RDG BREAKS DOWN AND THE FLOW ATTEMPTS TO BECOME MORE
ZONAL. THERE IS STILL SOME CONSTERNATION AMONG THE MDLS AS TO
EXACTLY WHEN THIS WL HAPPEN WHICH WOULD IMPACT HOW LONG THIS
BITTER COLD AIR MASS WOULD HANG AROUND WI. BESIDES THIS ARCTIC
BLAST...THE MAIN FOCUS TO BE ON THE ACCUMULATING SNOW POTENTIAL
SUNDAY INTO EARLY MON AS A PIECE OF ENERGY EJECTS OUT OF THE
LONGWAVE TROF.

HI PRES TO HANG TOUGH OVER THE GREAT LAKES SAT NGT...HOWEVER AS A
NEW SYSTEM ORGANIZES OVR THE SRN ROCKIES AT THE BASE OF THE
LONGWAVE TROF...THE ONSET OF BROAD ISEN LIFT WL BRING MID/HI
CLOUDS INTO WI...ESPECIALLY AFTER MIDNGT. THESE CLOUDS COULD PLAY
HAVOC WITH MIN TEMPS AS ANY DELAY WOULD ALLOW READINGS TO TANK.
STILL EXPECT SUB-ZERO TEMPS GENERALLY NW OF A LINE FROM WAUTOMA TO
MARINETTE WITH AREAS FROM THE FOX VALLEY TO LAKE MI GENERALLY IN
THE ZERO TO 5 ABOVE RANGE. WIND SPEEDS TO BE LIGHT/VARIABLE SAT
NGT...THUS WIND CHILL READINGS WL NOT APPROACH ADVY CRITERIA.

THIS ISEN LIFT IS FCST TO GRADUALLY INCREASE ACROSS WI ON SUNDAY
AND WHEN COMBINED WITH MID-LEVEL Q-G FORCING AND ADDITIONAL LIFT
FROM THE LEFT EXIT REGION OF THE UPR JET...IT APPEARS THAT LIGHT
SNOW WL BEGIN TO OVERSPREAD NE WI DURING THE MORNING HOURS AND
BECOME RATHER STEADY IN THE AFTERNOON. ACCUMULATIONS INITIALLY
SHOULD REMAIN UNDER AN INCH...ALTHO SOME LAKE ENHANCEMENT FROM
LAKE MI COULD BRING AN INCH OR TWO OF SNOW FROM SUE TO MTW BY 00Z
MON. THE ISEN LIFT WL HELP TO BRING A BOOST TO THE TEMPS WITH
READINGS GETTING INTO THE TEENS NORTH...AROUND 20 DEGS E-CNTRL WI.

THE SNOW WL THEN CONT THRU MOST (IF NOT ALL SUNDAY NGT) AS AN AREA
OF LOW PRES MOVES NEWD INTO CNTRL/ERN SECTIONS OF THE GREAT LAKES
BY 12Z MON. FAVORABLE MID-LEVEL FORCING AND UPR JET SUPPORT
PERSIST...THUS ANTICIPATE MEASURABLE SNOW FOR THE ENTIRE FCST
AREA. HIGHEST AMOUNTS SHOULD BE ALONG LAKE MI WHERE LAKE
ENHANCEMENT WL CONT THRU SUNDAY EVENING BEFORE WINDS BACK TO THE
NW. INDICATIONS SHOW A POTENTIAL ACCUMULATION TO RANGE FROM 2 TO 4
INCHES N-CNTRL WI...TO 4 TO 6 INCHES NEAR LAKE MI. WL CONT TO
HIGHLIGHT THIS POTENTIAL IN THE HWO AS MON MORNING`S COMMUTE COULD
BE A SLIPPERY AFFAIR ON AREA ROADWAYS. THE MEASURABLE SNOW IS FCST
TO GRADUALLY TAPER OFF FROM SW TO NE ON MON AS THE SYSTEM MOVES
INTO SE CANADA. THERE IS STILL SOME WEAK UPR TROFFING LEFT BEHIND
ACROSS WI DURING THE AFTERNOON...SO CANNOT COMPLETELY RULE OUT
SOME FLURRIES DURING THE AFTERNOON. BLUSTERY WEST WINDS WL BE LEFT
OVER THE REGION AS MAX TEMPS CONT TO RESIDE WELL BELOW NORMAL.

A WEAK SFC RDG IS PROGGED TO SLIDE ACROSS WI MON EVENING AND
ATTEMPT TO BREAK UP THE STUBBORN CLOUD DECK OVERHEAD. HOWEVER...A
FAST-MOVING NRN STREAM SHORTWAVE TROF IS EXPECTED TO DROP INTO THE
UPR MS VALLEY LATE MON NGT AND COULD ALREADY SPREAD LIGHT SNOW
INTO AT LEAST THE WRN HALF OF WI BY DAYBREAK. THIS COMPACT SYSTEM
HAS STRONG MID-LEVEL FORCING THANKS TO A STRONG EMBEDDED SHORTWAVE
AND MODEST ISEN LIFT PRECEDING IT...THUS HAVE RAISED POPS FOR AT
LEAST CNTRL WI LATE MON NGT AND WL PROBABLY NEED TO RAISE POPS IN
THE EAST HEADED INTO TUE MORNING. THIS SYSTEM RACES THRU THE GREAT
LAKES ON TUE AND COULD ALREADY BE EXITING THE ERN GREAT LAKES BY
00Z WED. SNOW ACCUMULATIONS SHOULD BE MINOR DUE TO THE FAST NATURE
OF THE SYSTEM AND A LACK OF DEEP MOISTURE AVAILABLE.

ANOTHER SURGE OF ARCTIC AIR TO OVERSPREAD THE REGION FOR MID-WEEK
AS 8H TEMPS DROP TO AROUND -22C. AN AREA OF HI PRES IS FCST TO
SLIDE INTO THE MIDWEST TUE NGT AND PUSH ACROSS SRN SECTIONS OF THE
GREAT LAKES ON WED. DEPENDING ON CLOUD COVER...TUE NGT/WED WOULD
BE THE COLDEST PERIOD OF THE EXTENDED FCST WITH TEMPS 15 TO 20
DEGS BELOW NORMAL. A SLIGHT MODERATION IN TEMPS IS EXPECTED BY THU
AS THE SFC HI HEADS TOWARD THE EAST COAST AND WINDS BACK TO THE
SW. MAX TEMPS ON THU COULD REACH THE MID TO UPR TEENS...STILL
AROUND 10 DEGS BELOW NORMAL.
&&

.AVIATION...FOR 06Z TAF ISSUANCE
ISSUED AT 1030 PM CST THU DEC 5 2013

AREA OF MVFR CIGS ACRS NRN WI HAS PROVED TOUGHER TO DISLODGE THAN
EXPECTED. WL KEEP THEM FOR A TIME IN THE NEW TAFS...THOUGH STILL
EXPECT THEM TO EVENTUALLY DISSIPATE.
&&

.GRB WATCHES/WARNINGS/ADVISORIES...
WIND CHILL ADVISORY UNTIL 9 AM CST THIS MORNING FOR WIZ005-010-
011-018-019-030.
&&

$$

SHORT TERM.....TE
LONG TERM......KALLAS
AVIATION.......SKOWRONSKI