000
FXUS63 KMQT 082102
AFDMQT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MARQUETTE MI
402 PM EST SUN DEC 8 2013

.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 400 PM EST SUN DEC 8 2013

WV IMAGERY AND RUC ANALYSIS INDICATED A BROAD MID/UPPER LEVEL TROUGH
OVER THE WRN CONUS RESULTING IN WSW FLOW FROM THE PLAINS INTO THE
GREAT LAKES. THE MAIN UPSTREAM SHORTWAVE TROUGH WAS MOVING THROUGH
SE CO. AT THE SFC...LIGHT WINDS PREVAILED ACROSS UPPER MICHIGAN AS
ARCTIC HIGH PRES EXTENDED FROM NEW ENGLAND INTO THE NRN GREAT LAKES.
A LOW PRES TROUGH STRETCHED FROM SW KS THROUGH THE OH VALLEY. A
BROAD AREA OF LIGHT SNOW SUPPORTED BY WAA/280K-290K ISENTROPIC
LIFT...HAD SPREAD FROM MN/IA/WI INTO UPPER MI. HOWEVER...SNOW HAS
BEEN VERY LIGHT WITH VSBY TO 2-4SM FROM MNM-ESC AND ABOVE 5SM FROM
IMT-IWD.

LATE THIS AFTERNOON AND TONIGHT...AS THE SHORTWAVE CONTINUES TO LIFT
TOWARD THE GREAT LAKES EXPECT THE SNOW INTENSITY TO SLOWLY INCREASE.
HOWEVER...WITH THE STRONGER 700-300 MB QVECTOR CONV REMAINING SOUTH
OF THE AREA AND ONLY 1-2 G/KG AVAILABLE...GOING QPF VALUES IN THE
0.08-0.20 RANGE REMAIN ON TRACK. EXPECT SLR VALUES FROM NEAR 20/1
SOUTH TO 15/1 NORTH AS THE DGZ IS DEEPER AND EXTENDS MORE FAVORABLY
INTO THE LAYER OF GREATER UPWARD MOTION OVER THE SOUTH COMPARED TO
THE SHALLOW DGZ FARTHER NORTH IN THE COLDER AIR.
SO...FCST SNOWFALL AMOUNTS OF AROUND AN INCH NORTH TO 1 TO 3 INCHES
SOUTH ARE INCLUDED. THE HIGHER RES MODELS SUGGEST THAT AN AREA OF
LOW LEVEL CONV OVER NRN LAKE MI AHEAD OF THE AREA OF STRONGER SE
WINDS MAY PUSH A BAND OF LAKE ENHANCED SNOW INTO LOCATIONS BORDER
THE BAY OF GREEN BAY AND LAKE MICHIGAN LATE THIS EVENING. SINCE THE
BAND IS EXPECTED TO BE TRANSIENT...ADDITIONAL SNOW AMOUNTS OF ONLY
AN INCH OR TWO ARE EXPECTED WITH THIS FEATURE. A PERIOD OF SRLY
WINDS INTO SCHOOLCRAFT COUNTY COULD ALSO BRING A PERIOD OF MODERATE
SNOW LATE TONIGHT.

MONDAY...THE FIRST OF SEVERAL EMBEDDED SHORTWAVE TROUGHS WITHIN THE
DEEP EASTERN CANADIAN TROUGH WILL BE PUSHING THROUGH THE AREA MONDAY
MORNING. THE NEXT INTRUSION OF ARCTIC AIR WILL BE PUSHING INTO THE
WESTERN CWA BEHIND A COLD FRONT AT THE START OF THE PERIOD. 850 MB
TEMPS FALLING TO -21 TO -23C BY THE AFTERNOON COMBINED WITH
INVERSION HEIGHTS RISING TO 8K-10K FT AND UNIDIRECTIONAL WESTERLY
WINDS SHOULD RESULT IN FAVORABLE LOW LEVEL CONV AND POTENTIAL FOR A
DOMINANT LES BAND INTO THE NRN KEWEENAW PENINSULA. WITH THE PASSAGE
OF THE SHRTWV...EXPECT THAT THE WINDS WOULD EVENTUALLY
VEER...PUSHING THE BAND SLOWLY TO THE SOUTH FROM NEAR EAGLE RIVER TO
CALUMET/MOHAWK AND TO HOUGHTON IN THE AFTERNOON. SNOWFALL
ACCUMULATIONS WILL GREATLY DEPEND ON HOW THE HEAVIER BAND LINGERS IN
ANY ONE LOCATION...BUT 12 HOUR ACCUMULATIONS OF AT LEAST 8 INCHES
REMAIN POSSIBLE. IN ADDITION...BLUSTERY WEST WINDS OF 20-30MPH WITH
GUSTS OVER 35 MPH WILL PRODUCE CONSIDERABLE BLOWING AND DRIFTING
SNOW AND VERY LOW VSBY. HOWEVER...SINCE THE HIGHER RES MODELS STILL
SHOW DIFFERENCES IN HANDLING WHERE THE BAND WILL DEVELOP AND HOW
LONG IT WILL LINGER...THE WATCH WAS NOT UPGRADED AT THIS TIME.

.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 400 PM EST SUN DEC 8 2013

ELOGATED AREA OF UPPER LEVEL TROUGHING STRETCHES FROM SKANDINAVIA
AND FAR NORTHWEST RUSSIA ACROSS THE NORTH POLE AND ACROSS MUCH OF
EASTERN CANADA AND AS FAR SOUTH AS THE WESTERN PORTIONS OF THE
CONUS. CORE OF COLDEST AIR RESIDES FROM NORTHERN GREENLAND ACROSS
CNTRL CANADA AND INTO THE NORTHERN PLAINS. H85 TEMP THIS MORNING
AT KINL WAS -25C WHILE IT WAS -17C AT KGRB. DECENT AGREEMENT THAT
UPCOMING WEEK WILL REMAIN CHILLY AS UPPER TROUGH BECOMES MORE
CENTERED OVER HUDSON BAY ALLOWING MULTIPLE PUSHES OF ARCTIC AIR TO
SWEEP ACROSS NORTHERN PLAINS AND GREAT LAKES IN NW FLOW ALOFT.
STILL INDICATIONS THAT COLD STARTS TO RELAX NEXT WEEKEND AS
TROUGHING REORIENTS FROM NORTH POLE TO DAVIS STRAIT AND GREENLAND
WHICH ALLOWS FOR MORE OF A ZONAL WEST-NORTHWEST FLOW ALOFT ACROSS
THE CONUS BY MIDDLE OF THE MONTH.

FIRST CONCERNING THE LK EFFECT ON MONDAY NIGHT. INITIAL SHORTWAVE IN
NW FLOW CURRENTLY OVER NORTHERN SASKATCHEWAN AND MANITOBA SWEEPS
ACROSS LK SUPERIOR REGION MONDAY AFTN. EXPECT MINIMAL SYNOPTIC
SUPPORT FOR ANY SNOW AS PVA/Q-VECTOR CONVERGENCE AT H7-H5/H85-H7
STAYS OVER LK SUPERIOR AND MAINLY NORTH. SFC LOW MOVING THROUGH ON
MONDAY DEEPENS NORTH OF LK SUPERIOR TOWARD JAMES BAY BY MONDAY
EVENING AS RESULT OF PVA/COLD AIR ADVECTION. RESULT IS INCREASING
UNSTABLE WESTERLY LOW- LEVEL FLOW ACROSS LK SUPERIOR. NAM SOUNDINGS
INDICATE VERY UNSTABLE CONDITIONS AS SHORTWAVE HELPS RAISE INVERSIONS
TO OVER 7KFT WITH LAKE EQL/S OVER 13KFT AT CMX AND P59 AND STDM4.
SFC-925MB STEERING WINDS VARY ENOUGH DURING PERIOD OF MOST FAVORABLE
INSTABILITY/MOSITURE/CONVERGENCE TO PEG WHERE HEAVIEST SNOW WILL
OCCUR. HIGH RES MODELS DO DIFFER HERE SOMEWHAT...WITH THE 12Z
REGIONAL GEM KEEPING THE STRONGEST CONVERGENCE MAINLY ALONG THE
NORTHWEST SHORE OF THE KEWEENAW THROUGH LATE AFTN...WHILE LOCAL WRF
IS MORE ON THE SOUTHERN EDGE...SETTING UP DOMINANT BAND MAINLY TO
SOUTH OF HOUGHTON AND HANCOCK. NAM AND NCEP WRF-ARW/NMM NESTS KIND OF
IN BTWN THOSE IDEAS. GIVEN THE DEGREE OF OVERWATER INSTABILITY...
POTENTIAL CERTAINTY THERE FOR TOTAL SNOW MONDAY AFTN THROUGH MONDAY
EVENING TO EXCEED A FOOT...IF THE BAND CAN PERSIST IN ONE LOCATION
FOR A WHILE. AT THE LEAST...MOST AREAS WILL SEE BURSTS OF HEAVIER
SNOW ALONG WITH STRONG/GUSTY WEST WINDS TO 40 MPH AND A LOT OF
BLOWING SNOW AND POOR VSBY. IN THE HEAVIER SNOW BAND...WHITEOUTS MAY
OCCUR MONDAY AFTN INTO MONDAY EVENING.

COORD WITH SHORT TERM FORECASTER AND DECIDED TO LEAVE GOING LK
EFFECT SNOW WATCH. NOT REALLY A QUESTION IF HEAVY LES/BLSN WILL
OCCUR...BUT MORE ONE OF WHERE THAT STRONG CONVERGENCE BAND WILL
DEVELOP. WILL LET MID SHIFT TAKE ANOTHER CRACK AT PINNING DOWN
LOCATION OF THE HEAVIER SNOW BAND.

ATTN LATER MONDAY NIGHT WILL BE ON SHORTWAVE PUSHING IN ACROSS
NORTHERN PLAINS AND ASSOCIATED SFC TROUGH. FIRST IMPACT FM THIS
WAVE WILL BE TO BACK WINDS SW...ALLOWING MOST OF HEAVIER LK EFFECT
SNOW TO PUSH OUT OVER LK SUPERIOR OFF THE KEWEENAW PENINSULA...THUS
THE ENDING TIME OF LATE MONDAY EVENING FOR LAKE EFFECT SNOW WATCH.
RIGHT AS THE LK EFFECT DIMINISHES FOR A WHILE...STILL APPEARS THAT
LGT SYNOPTIC SNOW WILL IMPACT MUCH OF CWA MAINLY IN THE MORNING.

BRIEF NOTE ABOUT WIND CHILLS FOR MONDAY NIGHT...INCREASING CLOUDS
AHEAD OF THE SYSTEM LATER MONDAY NIGHT SHOULD ALLOW TEMPS TO BEGIN TO
RISE. HAVE MINS WELL BLO ZERO...EVEN LESS THAN 10 BLO THROUGH EARLY
MORNING...THEN WITH THE ARRIVAL OF CLOUDS AND MORE WIND...EXPECT
TEMPS TO RISE TOWARD ZERO BY DAYBREAK ON TUESDAY. WILL BE CLOSE CALL
ON WIND CHILL READINGS NEAR CRITERIA BUT TEMPS MAY WARM JUST ENOUGH
TO KEEP WIND CHILLS GREATER THAN 25 BLO. AT THE LEAST...WIND CHILLS
WILL STILL BE A RATHER CHILLY 10 TO 20 BLO FOR MAJORITY OF WEST HALF
OF UPR MICHIGAN.

AS SFC LOW STRENGTHENS...MOISTURE/TEMPERATURE ADVECTION AHEAD OF
WAVE MIGHT RESULT IN MORE WIDESPREAD SNOW OVER EASTERN CWA LATE
MORNING INTO EARLY AFTN...WHERE A FEW INCHES OF SNOW COULD OCCUR.
OTHERWISE...EXPECT LESS THAN 1 INCH FOR THE CWA FROM THE SYSTEM.

ONCE THE SHORTWAVE AND SFC LOW CROSS THE AREA...SFC TROUGH ELONGATES
ACROSS SOUTHERN HALF OF LK SUPERIOR AND EVENTUALLY INTO NORTHERN
TIER OF UPR MICHIGAN. RESULT WILL BE LK EFFECT...MOSTLY OF MODERATE
INTENSITY...FOR THE WNW-NW FLOW AREAS. MOST CONCENTRATED/HEAVIER
SNOW SHOWERS LIKELY FOR THE SNOWBELTS OF ONTONAGON COUNTY FROM WHITE
PINE TO ROCKLAND AND ALSO TO THE EAST OF MUNISING AND TO THE NORTH
OF NEWBERRY...INCLUDING GRAND MARAIS. PERSISTENT LK EFFECT SETUP
CONTINUES THROUGH MUCH OF WEDNESDAY WITH INVERSIONS 5-8KFT AND
MORE THAN SUFFICIENT OVER-WATER INSTABILITY AS H85 TEMPS ARE NEAR
-25C. GIVEN SUCH COLD TEMPS THOUGH...SNOW WILL BE VERY FINE AND
MAIN ISSUE IN THE LK EFFECT AREAS WILL BE POWDERY SNOW BEING BLOWN
AROUND BY GUSTY WINDS RESULTING IN BLSN/POOR VSBY. AWAY FM THE LK
EFFECT COLD AIRMASS FIRMLY ENTRENCHED. SOME AREAS OF WESTERN CWA MAY
NOT REACH ZERO ON WEDNESDAY AFTN.

ANOTHER SYSTEM APPROACHING IN THE ACTIVE NW FLOW ALOFT COMES IN BY
THURSDAY MORNING. WINDS SHOULD BACK ENOUGH SW TO PUSH MOST OF THE LK
EFFECT OFFSHORE EXCEPT OVER THE KEWEENAW. HIGH PRESSURE RIDGE IN
VCNTY FIRST PART OF WED NIGHT WITH SUCH COLD AIRMASS SUGGESTS THAT
MINS COULD BE VERY LOW. LOWERED TEMPS TOWARD COLDER MOS NUMBERS...AND
FURTHER TWEAKED COLD SPOTS IN THE INTERIOR TOWARD 20 BLO ZERO. MAY BE
SIMILAR SETUP TO MONDAY NIGHT/TUESDAY NIGHT WHERE TEMPS RISE LATE.
MAIN CHANGE BESIDES LOWERING TEMPS WAS TO LOWER WIND SPEEDS TOO AS
WINDS MAY TRY TO GO CALM WITH THE RIDGE AROUND TO START THE NIGHT.
THUS...MAY NOT SEE WIND CHILL ISSUES UNLESS THAT INCOMING SYSTEM
TRENDS STRONGER.

IN WAKE OF THAT SYSTEM...SFC TROUGH SINKS ACROSS LK SUPERIOR AND UPR
MICHIGAN WHICH TURNS WINDS MORE NNW/N LATER THURSDAY AND FRIDAY.
KEPT IDEA OF INCREASING POPS FOR LK EFFECT ALONG MUCH OF LK SUPERIOR
COMPARED TO CONSENSUS POPS. MODELS HINT THAT WARMER AIR COULD TRY TO
WORK IN BY NEXT WEEKEND...AT LEAST RELATIVELY WARMER...AS FLOW SHOWS
SIGNS OF TRYING TO BECOME MORE ZONAL. MORE WIDESPREAD AREA OF WARM
AIR ADVECTION SNOW MAY TRY TO DEVELOP CLOSE TO THE REGION ALONG
RETREATING ARCTIC AIRMASS. THOSE TYPE OF DETAILS WILL BE HANDLED BY
LOW CHANCE POPS FOR THE TIME BEING. TEMPS THOUGH WARMER WILL STILL
BE RUNNING BLO NORMAL THROUGH THE END OF THE EXTENDED.
&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1218 PM EST SUN DEC 8 2013

A DISTURBANCE AND WIDESPREAD AREA OF LIGHT SNOW WILL MOVE FROM WI
INTO UPPER MICHIGAN THIS AFTERNOON. EXPECT -SN/MVFR CONDITIONS TO
SPREAD NE TO ALL TERMINALS DURING THE AFTERNOON...BEGINNING FIRST AT
KIWD. WITH KSAW CLOSER TO THE TRACK OF THE DISTURBANCE...IFR
CONDITIONS ARE MORE LIKELY TO DEVELOP THERE IN THE EVENING.
CONDITIONS SHOULD IMPROVE TO MVFR BY LATE TONIGHT OR MON MORNING AT
IWD AND SAW. LAKE EFFECT SNOW WITH LIFR VSBY IS EXPECTED AT CMX BY
MID MORNING AS WINDS VEER TO THE WEST.
&&

.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 400 PM EST SUN DEC 8 2013

A SERIES OF TROUGHS WILL CROSS LAKE SUPERIOR THROUGH THE UPCOMING
WEEK AND BRING MULTIPLE CHANCES OF GALES. THE FIRST WILL PASS
SOUTHEAST OF UPPER MI MONDAY MORNING. BEHIND THIS TROUGH...WINDS
WILL VEER TO THE WEST AND INCREASE TO GALES TO 35 TO 40 KNOTS ACROSS
LAKE SUPERIOR MONDAY AFTERNOON AND EVENING. AFTER A DECREASE TO 20
TO 30 KNOT SOUTHWEST WINDS TUESDAY MORNING...LOW PRESSURE WILL TRACK
EASTWARD ACROSS LAKE SUPERIOR ON TUESDAY AND PRODUCE ANOTHER ROUND
OF GALES TO 35 KNOTS BEHIND IT TUESDAY AFTERNOON AND EVENING. THE
WESTERLY WINDS WILL WEAKEN SLIGHTLY TO 20 TO 30 KNOTS FROM LATE
TUESDAY NIGHT INTO THURSDAY AS A WEAK RIDGE EXTENDING FROM HIGH
PRESSURE IN THE CENTRAL PLAINS SLOWLY BUILDS INTO THE AREA.
CONTINUED MODERATE TO HEAVY FREEZING SPRAY WILL BE POSSIBLE
THROUGHOUT THE PERIOD WITH SEVERAL PUSHES OF ARCTIC AIR ACROSS THE
LAKE. ANOTHER WEAK LOW PRESSURE SYSTEM WILL MOVE SOUTHEASTWARD
ACROSS LAKE SUPERIOR THURSDAY NIGHT INTO FRIDAY...BUT WINDS SHOULD
REMAIN UNDER 20 KNOTS THROUGH SATURDAY BEHIND THIS SYSTEM.
&&

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
  WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 9 AM EST
     MONDAY FOR MIZ007-014-085.

  LAKE EFFECT SNOW WATCH FROM MONDAY MORNING THROUGH MONDAY
     EVENING FOR MIZ001-003.

  WINTER WEATHER ADVISORY UNTIL 7 AM EST /6 AM CST/ MONDAY FOR
     MIZ012-013.

LAKE SUPERIOR...
  HEAVY FREEZING SPRAY WARNING FROM 7 PM MONDAY TO 7 AM EST
     TUESDAY FOR LSZ245-248>251-265>267.

  GALE WARNING FROM 1 PM MONDAY TO 5 AM EST TUESDAY FOR LSZ244-245-
     265>267.

  HEAVY FREEZING SPRAY WARNING FROM 1 PM EST /NOON CST/ MONDAY TO
     7 AM EST /6 AM CST/ TUESDAY FOR LSZ162-240>244-263-264.

  GALE WARNING FROM 4 PM MONDAY TO 5 AM EST TUESDAY FOR LSZ264.

  GALE WARNING FROM 1 PM MONDAY TO MIDNIGHT EST MONDAY NIGHT FOR
     LSZ263.

LAKE MICHIGAN...
NONE.
&&

$$

SHORT TERM...JLB
LONG TERM...JLA
AVIATION...JLB
MARINE...JLB