Winter Storm in Wisconsin, February 7, 2013

AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE GREEN BAY WI
502 AM CST THU FEB 7 2013

CORRECTED WORDING OF SYNOPSIS

.SYNOPSIS...ANOTHER ROUND OF ACCUMULATING SNOW FOR MOST OF THE
AREA THIS AFTERNOON INTO THIS EVENING.

UPR PATTERN ACRS NOAM TRANSITIONING INTO A SPLIT FLOW REGIME. THAT
WL ALLOW TEMPS TO RETURN TO AOA NORMAL LEVELS...THOUGH COULD STILL
BE A COUPLE COLD NIGHTS IF SKIES CLEAR AND WINDS GO CALM.
COMBINATION OF STORM SYSTEM CROSSING THE REGION TODAY/TONIGHT AND
MAJOR CYCLONE EJECTING OUT OF THE PLAINS THIS WEEKEND IN THE SRN
STREAM OF THE SPLIT FLOW WL LEAD TO ABV NORMAL PCPN FOR THE
PERIOD.
&&

.SHORT TERM...TDA/TNGT/FRI. INITIAL BAND OF SNOW WITH THE STG
ISENT LIFT THAT SWEPT ACRS THE AREA LATE YDA RACED THROUGH EVEN
FASTER THAN EXPECTED. HAVE SPENT MOST OF THE NGT WITH JUST FZDZ
ACRS THE AREA...AND IT HAS BEEN QUITE HEAVY AT TIMES. THE FZDZ WAS
BEING CAUSED BY WEAK LIFT IN LINGERING LOW-LEVEL WAA REGIME. TEMP
PROFILES STILL COLD ENOUGH TO SUPPORT SNOW...BUT MID-LVL MOISTURE
WAS STRIPPED OUT SO THERE WERE NO ICE-CRYSTALS BEING INTRODUCED
INTO THE LOW CLDS. THAT WAS NICELY ILLUSTRATED BY SNOW STILL
FALLING JUST S OF THE FCST AREA WERE TEMPS ALOFT WERE ACTUALLY
WARMER...BUT WHERE MOISTURE WAS MUCH DEEPER. REPORTS RECEIVED AT
THE OFFICE SUGGEST CONDITIONS IN N-C WI POOR ENOUGH TO JUSTIFY
GOING WITH A SHORT-TERM WINTER WX ADVISORY TO COVER THE MORNING
COMMUTE.

UPR SHRTW WL HEAD TOWARD THE AREA TDA. IT WL BE SHARPENING AS
SPEED MAX DEVELOPS ON THE BACK SIDE OF THE TROF. THAT WL LEAD TO
AN INCR IN LIFT DURING THE DAY. SO AT SOME POINT...MOISTURE WL
DEEPEN ENOUGH TO HAVE ICE CRYSTALS AGAIN...AND PCPN WL TURN BACK
TO SNOW. SINCE PCPN TYPE IN THIS CASE IS REALLY A FUNCTION OF
MOISTURE/LIFT RATHER THAN TEMPERATURE...THE CHANGEOVER WL PROBABLY
NOT OCCUR FM NW-SE AS TYPICAL. THERE PROBABLY WON/T BE A SMOOTH
TRANSITION LINE EITHER...AND THE CHANGE MAY VERY WELL OCCUR FM
S-N AS THE FORCING AHEAD OF THE SHRTWV STRENGTHENS.

ONCE PCPN CHGS TO SNOW...QUESTION IS NOW MUCH. THIS WL BE A
COMPACT DEEPENING SYSTEM...AND THOSE ARE FREQUENTLY TROUBLE. HAVE
TRENDED FCST TOWARD THE STRONGER/SLOWER MODELS. THAT MEANT BUMPING
UP SNOW TOTALS IN THE SE 1/2 OF THE FCST AREA...KEEPING THE SNOW
GOING THROUGH THE EVENING IN THE SE PART OF THE AREA...AND
EXTENDING ADVISORY TO 06Z IN E-C WI. WOULD NOT BE SURPRISED TO END
UP WITH SOME WARNING CRITERIA TOTALS OVER THE FAR SE...ESP IF WE
GET A LAKE CONTRIBUTION AT THE VERY END OF THE EVENT. TOUGH
CALL...BUT AT THIS POINT THE OVERALL SCENARIO STILL SEEMED MORE
LIKE A HIGH-END ADVISORY RATHER THAN A LOW-END WARNING. BUT DAY
SHIFT WL NEED TO KEEP A CLOSE EYE ON THAT. ALSO CONCERNED WE COULD
HAVE SOME HEAVY SNOW IN E-C WI JUST IN TIME FOR THE AFTN COMMUTE.
WL BE SURE TO HIGHLIGHT THAT IN THE PRODUCTS.

SFC RIDGE WL BUILD IN STARTING LATE TNGT AND FOR FRI...WITH MUCH
QUIETER WX THEN.

.LONG TERM...FRIDAY NIGHT THROUGH NEXT WEDNESDAY.

THE LATEST GFS ENSEMBLE MEAN INDICATES THAT A DEEP WEST COAST
UPPER TROUGH WILL LIFT OFF TO THE NORTHEAST THIS WEEKEND AND
EVENTUALLY DEVELOP INTO A LONGWAVE TROUGH CENTERED OVER THE GREAT
LAKES BY THE MIDDLE OF NEXT WEEK. THE MAIN FORECAST CONCERN IN THE
EXTENDED PORTION OF THE FORECAST IS THE ROCKY MOUNTAIN CYCLONE DUE
TO MOVE ACROSS THE REGION LATE THIS WEEKEND INTO EARLY NEXT WEEK.
MEDIUM RANGE MODELS TONIGHT ARE CLUSTERING TIGHTER IN REGARDS TO
THE TRACK/TIMING OF THIS CYCLONE. WILL USE THE TIGHT CLUSTER OF
THE GFS/GEM/GFS ENSEMBLE MEAN.

FRIDAY NIGHT THROUGH SATURDAY NIGHT...HIGH PRESSURE RIDGE AXIS
WILL BE CENTERED ACROSS THE REGION FRIDAY EVENING BEFORE SHIFTING
TO THE CENTRAL GREAT LAKES OVERNIGHT. ONLY THING THAT WOULD HOLD
BACK TEMPS FROM PLUMMETING WOULD BE CIRRUS OVERHEAD...BUT ITS
ALWAYS HARD TO SAY HOW THICK IT WILL BE. WILL KEEP PARTLY CLOUDY
CONDITIONS OVER N-C WISCONSIN AND MOSTLY CLEAR ELSEWHERE. WITH
LIGHT WINDS...WILL DROP TEMPS SEVERAL DEGREES. HIGH PRESSURE WILL
SHIFT EAST OF THE AREA ON SATURDAY BUT WILL STILL HAVE A DRY SE
FEED OF AIR IN THE LOW LEVELS. SHOULD BE A LITTLE MORE IN THE WAY
OF MID-LEVEL CLOUDS...THOUGH NOT ENOUGH FOR PRECIP CONCERNS. THE
ROCKY MOUNTAIN CYCLONE WILL GATHER STRENGTH OVER THE CENTRAL
PLAINS SATURDAY NIGHT...BUT THINK MODELS ARE A TAD TOO AMBITIOUS
MOVING PRECIP INTO THE AREA...SINCE SE WINDS WILL PERSIST THROUGH
THE NIGHT. CLOUDS SHOULD BE ON THE INCREASE HOWEVER. HIGHS ON
SATURDAY WILL BE A FEW DEGREES ON EITHER SIDE OF THE THIRTY
MARK...WHILE LOWS WILL WARM TO AROUND 20 DEGREES ON SATURDAY
NIGHT.

REST OF THE FORECAST...THE ROCKY MOUNTAIN CYCLONE WILL TRACK
NORTHEAST INTO NORTHERN IOWA BY SUNDAY EVENING AND ACROSS
WISCONSIN FROM ABOUT LA CROSSE TO DOOR COUNTY SUNDAY NIGHT BEFORE
EXITING. AN ARCING BAND OF PRECIPITATION WILL BE SHIFTING
NORTHEAST ON SUNDAY AHEAD OF THE CYCLONE...BUT FAVOR A SLOWER
ARRIVAL TIME OF THE PRECIP DUE TO THE DRY SOUTHEAST WIND IN THE
LOW LEVELS. MUCH OF THE AREA SHOULD SEE PRECIP ARRIVE BY 00Z
MONDAY EXCEPT FOR MAYBE THE DOOR PENINSULA. THINK MOST OF THE AREA
WILL SEE PRECIP START OUT AS ALL SNOW...THOUGH SLEET OR RAIN COULD
BE MIXING IN OVER THE SOUTHERN FOX VALLEY AND LAKESHORE AREAS.
WARM AIR WILL CONTINUE TO SURGE NORTH AHEAD OF THE LOW SUNDAY
NIGHT...GIVING AREAS FROM CENTRAL WISCONSIN TO FAR NORTHEAST
WISCONSIN A CHANCE OF MIXED PRECIPITATION OR ALL RAIN. THE ARRIVAL
OF THE DRY SLOT SUNDAY NIGHT MAY ALSO CAUSE PRECIPITATION TO
TRANSITION INTO DRIZZLE OR FREEZING DRIZZLE UNTIL DEEPER MOISTURE
RETURNS LATE IN THE NIGHT. FOR SNOW FALL AMOUNTS...NORTH-CENTRAL
WISCONSIN SHOULD SEE THE HIGHEST TOTALS...AND COULD SEE A SOLID OR
HIGH END ADVISORY EVENT...BARRING THE SURGE OF WARM AIR DOES NOT
MAKE IT THAT FAR NORTH. THE CYCLONE WILL BE DEPARTING ON MONDAY
AND COLDER AIR WILL BE WRAPPING AROUND BACK INTO THE REGION
THROUGH THE DAY. MIXED PRECIPITATION OR ALL RAIN WILL BE
TRANSITION BACK TO SNOW OVER NORTHEAST WISCONSIN. NOT ANTICIPATING
ALOT OF ACCUMS ON MONDAY. BUT N-C WISCONSIN WILL LIKELY SEE SHARP
CYCLONIC FLOW AS WINDS TURN TO THE NORTHWEST...WHICH COULD SPELL
TROUBLE FOR THE LAKE EFFECT PRONE AREAS. DEFINITELY SOMETHING TO
KEEP AN EYE ON. HIGH PRESSURE WILL BE MOVING ACROSS THE AREA
MONDAY NIGHT THROUGH TUESDAY NIGHT...WHICH LOOK DRY AND SEASONABLE
AWAY FROM THE LAKE EFFECT SNOW BELTS. WISCONSIN LOOKS TO BE
BETWEEN SYSTEMS ON WEDNESDAY WHICH WILL CONTINUE THE DRY STREAK.
&&

.AVIATION...FOR 12Z TAF ISSUANCE. POOR FLIGHT CONDITIONS IN IFR OR
LIFR RANGE EXPECTED MOST OF THE DAY. A SLOW IMPROVEMENT SHOULD
BEGIN TO WORK ACRS THE AREA FM W-E STARTING THIS EVENING.
&&

.GRB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR WIZ022-
038>040-048>050.

WINTER WEATHER ADVISORY UNTIL 9 PM CST THIS EVENING FOR WIZ013-
020-021-031-037-045-073-074.

WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR WIZ030-
035-036.

WINTER WEATHER ADVISORY UNTIL 9 AM CST THIS MORNING FOR WIZ005-
010>012-018-019.

&&

SKOWRONSKI/MPC

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GREEN BAY WI
412 AM CST THU FEB 7 2013

WIZ005-010>013-018>022-030-031-035>040-045-048>050-073-074-081200-
VILAS-ONEIDA-FOREST-FLORENCE-NORTHERN MARINETTE-LINCOLN-LANGLADE-
MENOMINEE-NORTHERN OCONTO-DOOR-MARATHON-SHAWANO-WOOD-PORTAGE-
WAUPACA-OUTAGAMIE-BROWN-KEWAUNEE-WAUSHARA-WINNEBAGO-CALUMET-
MANITOWOC-SOUTHERN MARINETTE-SOUTHERN OCONTO-
412 AM CST THU FEB 7 2013

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTH CENTRAL AND NORTHEAST
WISCONSIN.

.DAY ONE...TODAY AND TONIGHT

HAZARDOUS TRAVEL CONDITIONS WILL CONTINUE THROUGH LATE TONIGHT.
ROADWAYS ARE LIKELY EITHER TO BE SNOW COVERED OR ICE COVERED AS A
RESULT OF WIDESPREAD FREEZING DRIZZLE WHICH FELL OVERNIGHT. THE
MIXED PRECIPITATION WILL CHANGE OVER TO ALL SNOW AGAIN DURING THE
DAY. THE SNOW MAY BECOME HEAVY AT TIMES OVER THE FOX VALLEY AND
LAKESHORE LATE THIS AFTERNOON AND EARLY THIS EVENING.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

ANOTHER STORM SYSTEM IS EXPECTED TO IMPACT THE AREA SUNDAY AND
MONDAY. THE PROJECTED LOW PRESSURE TRACK THROUGH NORTHERN
WISCONSIN MAY ALLOW WARM AIR TO GET PULLED INTO THE STATE...
RESULTING IN A RAIN AND SNOW MIX. IF THIS TRACK IS ACCURATE...THE
BEST CHANCE OF HEAVY SNOW WILL BE OVER NORTH CENTRAL WISCONSIN.
SINCE THE TRACK OF THIS SYSTEM IS STILL UNCERTAIN...PEOPLE WITH
TRAVEL PLANS LATE THIS WEEKEND ARE URGED TO STAY ABREAST OF THE
LATEST FORECASTS.

.SPOTTER INFORMATION STATEMENT...

SPOTTERS ARE REQUESTED TO FORWARD SNOWFALL MEASUREMENTS TO THE
NATIONAL WEATHER SERVICE IN GREEN BAY.

LMZ521-522-541>543-081200-
THE BAY OF GREEN BAY SOUTH OF A LINE FROM CEDAR RIVER MI TO ROCK
ISLAND PASSAGE-LAKE MICHIGAN FROM WASHINGTON ISLAND TO SHEBOYGAN-
412 AM CST THU FEB 7 2013

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTHWEST LAKE
MICHIGAN AND THE WATERS OF GREEN BAY.

.DAY ONE...TODAY AND TONIGHT

NORTHERLY GUSTS APPROACHING GALE FORCE ARE POSSIBLE TONIGHT.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW.

JS/MPC

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREEN BAY WI
255 AM CST THU FEB 7 2013

WIZ005-010>013-018>022-030-031-035>040-045-048>050-073-074-071100-
VILAS-ONEIDA-FOREST-FLORENCE-NORTHERN MARINETTE-SOUTHERN MARINETTE-
LINCOLN-LANGLADE-MENOMINEE-NORTHERN OCONTO-SOUTHERN OCONTO-DOOR-
MARATHON-SHAWANO-WOOD-PORTAGE-WAUPACA-OUTAGAMIE-BROWN-KEWAUNEE-WAUSHARA-
WINNEBAGO-CALUMET-MANITOWOC-
INCLUDING EAGLE RIVER...RHINELANDER...CRANDON...CRIVITZ...TOMAHAWK...
ANTIGO...STURGEON BAY...WAUSAU...WISCONSIN RAPIDS...STEVENS POINT...
APPLETON...GREEN BAY...ALGOMA...WAUTOMA...OSHKOSH...CHILTON AND TWO
RIVERS
255 AM CST THU FEB 7 2013

...FREEZING DRIZZLE AND LIGHT SNOW CAUSING HAZARDOUS TRAVEL CONDITIONS
ACROSS THE AREA...

THE COMBINATION OF THE SNOW WHICH FELL LATE WEDNESDAY AND FREEZING
DRIZZLE THAT WAS OCCURRING OVERNIGHT WERE RESULTING IN HAZARDOUS TRAVEL
CONDITIONS EARLY THIS MORNING. ROADWAYS ACROSS THE ENTIRE AREA WERE
REPORTED TO BE EITHER SNOW COVERED OR ICE COVERED AND SLIPPERY.
CONDITIONS IN MOST AREAS ARE NOT LIKELY TO IMPROVE MUCH BEFORE THE
MORNING COMMUTE. BUT TEMPERATURES ARE WARM ENOUGH THAT ROAD CREWS IN
URBAN AREAS MAY BE ABLE TO MELT SOME OF THE ICE OR SNOW BY TREATING THE
ROADS WITH SALT OR OTHER MELTING AGENTS. ANYONE TRAVELING EARLY THIS
MORNING SHOULD USE EXTRA CAUTION.

SKOWRONSKI
WEATHER.GOV/GREENBAY

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREEN BAY WI
535 AM CST THU FEB 7 2013

WIZ005-010>013-018>022-030-031-035>040-045-048>050-073-074-071530-
VILAS-ONEIDA-FOREST-FLORENCE-NORTHERN MARINETTE-SOUTHERN MARINETTE-
LINCOLN-LANGLADE-MENOMINEE-NORTHERN OCONTO-SOUTHERN OCONTO-DOOR-
MARATHON-SHAWANO-WOOD-PORTAGE-WAUPACA-OUTAGAMIE-BROWN-KEWAUNEE-WAUSHARA-
WINNEBAGO-CALUMET-MANITOWOC-
INCLUDING EAGLE RIVER...RHINELANDER...CRANDON...CRIVITZ...TOMAHAWK...
ANTIGO...STURGEON BAY...WAUSAU...WISCONSIN RAPIDS...STEVENS POINT...
APPLETON...GREEN BAY...ALGOMA...WAUTOMA...OSHKOSH...CHILTON AND TWO
RIVERS
535 AM CST THU FEB 7 2013

...FREEZING DRIZZLE AND LIGHT SNOW CAUSING HAZARDOUS TRAVEL CONDITIONS
ACROSS THE AREA...

THE COMBINATION OF THE SNOW WHICH FELL LATE WEDNESDAY AND FREEZING
DRIZZLE THAT OCCURRED OVERNIGHT WAS RESULTING IN HAZARDOUS TRAVEL
CONDITIONS THIS MORNING. ROADWAYS ACROSS THE ENTIRE AREA WERE
REPORTED TO BE EITHER SNOW COVERED OR ICE COVERED AND SLIPPERY.
THE POOR ROAD CONDITIONS ARE LIKELY TO CONTINUE IN MOST AREAS THROUGH
THE MORNING COMMUTE...THOUGH TEMPERATURES ARE WARM ENOUGH THAT ROAD
CREWS MAY BE ABLE TO MELT SOME OF THE ICE USING SALT OR OTHER MELTING
AGENTS.

PRECIPITATION EARLY THIS MORNING WAS PRIMARILY IN THE FORM OF FREEZING
DRIZZLE. THAT WILL LIKELY CONTINUE THROUGH MID-MORNING. DURING THE LATE
MORNING AND EARLY AFTERNOON...THE PRECIPITATION IS EXPECTED TO START TO
INCREASE IN INTENSITY...AND SWITCH BACK OVER TO SNOW. TIMING OF THE
CHANGE TO SNOW IS SOMEWHAT UNCERTAIN. THE BEST ESTIMATE IS THAT IT WILL
OCCUR IN THE LATE MORNING AT AREAS ALONG AND SOUTH OF HIGHWAY 29 WHICH
RUNS FROM WAUSAU TO GREEN BAY TO KEWAUNEE...BUT IT MAY TAKE UNTIL EARLY
AFTERNOON TO GET A COMPLETE CHANGEOVER FARTHER NORTH.

ONCE THE PRECIPITATION CHANGES TO SNOW...THE SNOW IS EXPECTED TO
CONTINUE FOR THE REST OF THE AFTERNOON. THE SNOWS WILL BE RATHER LIGHT
OVER NORTH-CENTRAL WISCONSIN...AND SOMEWHAT HEAVIER TO THE SOUTH AND
EAST. IN FACT...A PERIOD OF HEAVY SNOW COULD HIT THE GREEN BAY...FOX
CITIES...AND LAKESHORE AREAS JUST IN TIME OF THE AFTERNOON COMMUTE.

THE SNOW WILL START TO DIMINISH ACROSS CENTRAL AND NORTH-CENTRAL
WISCONSIN EARLY IN THE EVENING. THAT TREND WILL WORK EAST...BUT IT WILL
PROBABLY TAKE UNTIL AROUND MIDNIGHT FOR SNOWS ALONG THE LAKESHORE TO
TAPER OFF. THE TOTAL SNOW ACCUMULATION TODAY AND TONIGHT SHOULD RANGE
FROM AROUND AN INCH OVER FAR NORTH-CENTRAL WISCONSIN...TO 4 TO 6 INCHES
ALONG THE LAKESHORE FROM KEWAUNEE SOUTHWARD.

ANYONE TRAVELING TODAY OR TONIGHT SHOULD EXPECT TO ENCOUNTER POOR TRAVEL
CONDITIONS. PLAN ON A SLOWER THAN NORMAL TRIP...AND USE EXTRA CAUTION.

SKOWRONSKI
WEATHER.GOV/GREENBAY