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000
FXUS63 KGRB 030954
AFDGRB

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREEN BAY WI
354 AM CST MON MAR 3 2014

FORECAST DISCUSSION FOR ROUTINE MORNING FORECAST ISSUANCE

.SYNOPSIS...
ISSUED AT 341 AM CST MON MAR 3 2014

BITTERLY COLD TODAY...SOME SNOW TONIGHT...THEN A GRADUAL
MODERATION IN TEMPERATURES.

UPR FLOW ACR NOAM IS SPLIT...WITH BLOCKY NRN STREAM ACRS CANADA
AND PROGRESSIVE AND INCREASINGLY ZONAL SRN STREAM ACRS THE CONUS.
WEAK DISTURBANCES RIDING EWD IN THE ZONAL FLOW WL BRING SEVERAL
ROUNDS OF PCPN TO THE AREA. TIMING OF THOSE EVENTS WILL BECOME
INCREASINGLY DIFFICULT WITH TIME. AMOUNTS WL BE LGT...SO BLO
NORMAL PCPN EXPECTED FOR THE PERIOD.

AFTER ONE MORE DAY LOCKED IN THE ICY GRIP OF THE ARCTIC AIR...A
SLOW MODERATION IN TEMPERATURES IS EXPECTED...THOUGH THERE COULD
BE A MINOR SET BACK NEXT WEEKEND. OVERALL...READINGS WL REMAIN
BELOW NORMAL UNTIL PERHAPS THE VERY END OF THE FCST PERIOD.
&&

.SHORT TERM...TODAY...TONIGHT...AND TUESDAY
ISSUED AT 341 AM CST MON MAR 3 2014

AFTER THE BITTER COLD AND YET ANOTHER ROUND OF RECORD LOW
TEMPERATURES AT MANY SITES THIS MORNING...ANOTHER ROUND OF SNOW
IS ON TAP FOR TNGT. FORCING WL COME FM ISENT LIFT...SOME QG
FORCING AHEAD OF WK MID-LVL SHRTWV...AND RRQ OF RATHER POORLY
DEFINED UPR JET. MOISTURE WL BE LIMITED...THOUGH 00Z RAOBS
INDICATED PLUME OF MID-LVL MOISTURE WORKING EWD ACRS THE NRN
ROCKIES. THE DIFFUSE FORCING MAKES IT DIFFICULT TO PIN DOWN THE
AXIS OF MAX SNOWFALL...AND MODELS OFFERED VARYING IDEAS ABOUT
THAT. BEST GUESS IS THAT IT WL LINE UP FM THE AUW/RHI AREAS...ESE
THROUGH GRB...THOUGH CONFIDENCE IN THAT IS NOT HIGH. THE ONE
FAVORABLE FACTOR FOR SNOW IS THE VERY DEEP DENDRITIC SNOW GROWTH
ZONE ACRS MUCH OF THE FCST AREA...AND A FAIRLY PROLONGED PERIOD OF
DEEP SATURATION. WL GO WITH 1-3 INCH AMNTS ACRS THE AREA...BUT
IT/S POSSIBLE THERE COULD BE A BAND OF 2-4 INCHES IF THE FORCING
BECOMES MORE FOCUSED.

GIVEN THE BAROCLINIC ZONE LINGERING ACRS THE AREA...THINK LGT SNOW
AND FLURRIES WL LINGER WELL INTO THE DAY TUE. CARRIED LIKELY POPS
INTO THE MORNING ACRS MAINLY E-C/NE WI...THEN LINGERED LOW-END
POPS ACRS ALMOST ALL OF THE AREA FOR THE REST OF THE DAY.

STUCK CLOSE TO BLEND OF BEST PERFORMING GUIDANCE...THOUGH RAISED
MINS A BIT IN E-C WI TNGT DUE TO CLDS AND SNOW.

NOT REAL THRILLED WITH THE WIND CHILL ADVISORY AS MANY SITES ACRS
THE FCST AREA ARE FLAT OUT CALM. BUT GIVEN ALL SURROUNDING WI
OFFICES WERE KEEPING THEIR ADVISORIES GOING...WL DO THE SAME.

.LONG TERM...TUESDAY NIGHT THROUGH SUNDAY
ISSUED AT 341 AM CST MON MAR 3 2014

MEAN FLOW ACROSS THE CONUS TO BE SLIGHTLY AMPLIFIED...BUT
PROGRESSIVE WITH TWO DISTINCTIVE UPR TROFS TRAVERSING THE COUNTRY.
MDLS ARE ALSO LESS EMPHATIC WITH THE SUSTAINABILITY OF THE WEST
COAST UPR RDG NEXT WEEKEND...THUS MORE OF A ZONAL FLOW WHICH WOULD
KEEP AN ACTIVE WEATHER PATTERN INTACT FOR NE WI. TEMPS TO WARM
THRU FRI BEFORE A CDFNT MOVES THRU AND SENDS READINGS DOWN IN THE
OTHER DIRECTION.

THE NEXT QUICK-MOVING WEAK SHORTWAVE TROF TO ALREADY BE KNOCKING
ON OUR DOOR TUE NGT WITH ONLY MODEST MID-LEVEL FORCING
EVIDENT...BUT LITTLE ELSE EITHER AT THE SFC OR JET LEVEL. THERE
ARE ALSO ISSUES AS TO BOTH HOW FAR NORTH ANY SNOW CAN MAKE IT AND
HOW FAST TO BRING THE SNOW ACROSS WI. THE NAM IS BY THE FAR THE
SLOWEST...THE ECMWF IS FARTHEST NORTH AND THE UKMET THE FASTEST. A
SPRAWLING AREA OF HI PRES STRETCHED ACROSS ONTARIO WL LIMIT THE
NRN EXTENT OF ANY SNOW WHICH WOULD FAVOR THE SRN HALF OF THE
STATE. THE PROGRESSIVE NATURE OF THE MEAN FLOW WOULD FAVOR A
FASTER MOVEMENT OVERALL...THUS SHIED AWAY FROM THE NAM.
THEREFORE...USED A BLEND OF THE GFS/GEM WHICH BRINGS A CHC OF
LIGHT SNOW GENERALLY SOUTH OF HWY 29. DUE TO THE FAST NATURE OF
THIS SYSTEM...ACCUMULATIONS APPEAR MINOR WITH LESS THAN AN INCH
EXPECTED. FINALLY...MIN TEMPS ARE STILL TRICKY ACROSS THE NORTH AS
ANY BREAKS IN THE CLOUDS...COUPLED WITH LIGHT WINDS...COULD ALLOW
READINGS TO CRASH. IT NOW APPEARS THAT ENUF CLOUD COVER SHOULD
HOLD THRU THE NGT TO HAVE MIN TEMPS FALL INTO THE SINGLE DIGITS
EITHER ABOVE OR BELOW ZERO ACROSS NE WI.

THIS LARGE AREA OF HI PRES IS FCST TO SETTLE SWD INTO SRN
SECTIONS OF ONTARIO/QUEBEC ON WED AND SEND A DRY E-NE WIND INTO
THE FCST AREA. THIS AIR MASS MAY NOT BE DRY ENUF TO SCOUR OUT ALL
THE CLOUDS...THUS A PARTLY SUNNY TO MOSTLY CLDY SKY IS
ANTICIPATED. WL CONT TO WATCH ERN WI FOR ANY POTENTIAL LAKE
EFFECT...BUT A LACK OF SIGNIFICANT OPEN WATER WOULD LIMIT ANY
ACTIVITY. MAX TEMPS ARE EXPECTED TO REACH THE 15 TO 20 DEG RANGE
OVER MUCH OF NE WI.

THIS SFC HI BEGINS TO SHIFT EAST WED NGT AND GRADUALLY LOSE ITS
GRIP OVER THE WRN GREAT LAKES. QUESTIONS THEN ARISE WITH THE
HANDLING OF THE NEXT SYSTEM MOVING ALONG THE U.S.-CANADIAN BORDER.
THE GFS/GEM REMAIN ADAMANT THAT THIS SYSTEM COULD BRING WAA-
INDUCED PCPN INTO WI LATE WED NGT. THE ECMWF HAS A MORE NRN TRACK
OF THIS SYSTEM ACROSS SRN CANADA. FOR NOW...HAVE ESSENTIALLY SPLIT
THE DIFFERENCE AND HELD OFF ON ANY POPS FOR WED NGT. FCST FOR THU
COMES DOWN TO WHICH CAMP YOU BELIEVE IN AS THE GFS WOULD SPREAD
ACCUMULATING SNOW THRU ALL OF NE WI...WHILE THE ECWMF JUST BRUSHES
THE NORTH DURING THE AFTERNOON. THERE ARE ALSO ISSUES WITH THE
SPEED OF AN EWD MOVING CDFNT (A GOOD 12 HOUR DIFFERENCE) AMONG THE
MDLS. UNTIL THIS SITUATION BECOMES LESS MUDDLED...HAVE FOLLOWED
THE CONSENSUS SOLUTION WHICH KEEPS A LOW POP OVER THE REGION ON
THU.

THE CHCS FOR PCPN WOULD THEN CONT THRU AT LEAST THU NGT...IF NOT
THRU FRI (MDL DEPENDENT) AS THE CDFNT PUSHES THRU WI. THE MAIN UPR
FORCING TO REMAIN ACROSS NRN SECTIONS OF THE GREAT LAKES...THUS
LEAVING THE FNT ITSELF TO BE THE PRIMARY PCPN PRODUCER. THERE IS
ENUF MOISTURE EVIDENT SUCH THAT A MINOR ACCUMULATION CAN BE
EXPECTED. IT IS JUST A MATTER WHETHER THIS SNOW FALLS THU NGT OR
FRI. HOPEFULLY...THE MDLS WL GET IN BETTER SYNC WITH THIS SYSTEM
IN THE COMING DAYS. THE TIMING OF THE CDFNT WL ALSO IMPACT MAX
TEMPS ON FRI AND WHETHER VALUES CAN REACH THE 30 DEG MARK.

AFTER ALL THE UNCERTAINTY ON THU AND FRI...THE MDLS DO AGREE ON
DROPPING ANOTHER AREA OF HI PRES INTO THE NRN PLAINS FRI NGT AND
EDGING EWD ACROSS THE UPR MS VALLEY ON SAT. EXPECT TO SEE A
GRADUAL DECREASE IN CLOUDS (ESPECIALLY ON SAT)...BUT A COOL NW
FLOW WL KEEP MAX TEMPS IN THE 20S. THIS HI PRES IS PROGGED TO MOVE
INTO THE WRN GREAT LAKES SAT NGT AND STRETCH FROM TX NE TO THE ERN
GREAT LAKES ON SUNDAY. THE NEXT CDFNT WL BE IN THE PROCESS OF
DROPPING SEWD THRU THE UPR MS VALLEY LATER ON SUNDAY...BUT MOST OF
THE PCPN CHCS ASSOCIATED WITH THIS FEATURE TO ARRIVE SUNDAY NGT.
&&

.AVIATION...FOR 12Z TAF ISSUANCE
ISSUED AT 341 AM CST MON MAR 3 2014

VFR CONDITIONS TDA WL DETERIORATE TO LOWER MVFR OR IFR FM NW-SE
THIS EVNEING AS SNOW OVERSPREAD THE AREA. MVFR CONDITIONS LIKELY
TO LINGER TUE IN THE WAKE OF THE MAIN BAND OF SNOW.
&&

.GRB WATCHES/WARNINGS/ADVISORIES...
WIND CHILL ADVISORY UNTIL 9 AM CST THIS MORNING FOR WIZ005-
010>013-018>022-030-031-035>040-045-048>050-073-074.
&&

$$

SYNOPSIS.......SKOWRONSKI
SHORT TERM.....SKOWRONSKI
LONG TERM......KALLAS
AVIATION.......SKOWRONSKI