431 
FXUS63 KMQT 192340
AFDMQT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MARQUETTE MI
640 PM EST TUE FEB 19 2013

.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 430 PM EST TUE FEB 19 2013

WV IMAGERY AND RUC ANALYSIS INDICATED A NEG-TILT MID/UPPER LEVEL 
TROUGH FROM HUDSON BAY THROUGH NW ONTARIO INTO WI/LOWER MI BEING 
PROPELLED SLOWLY EAST BY A 110-120 KT 300-250 JET MOVG THROUGH THE 
OHIO VALLEY TOWARD THE EASTERN LAKES IN THE BASE OF THE TROUGH. 
THE BACK EDGE OF A WELL-DEFINED WARM CONVEYOR SHIELD EXTENDS BACK 
INTO ERN LAKE SUPERIOR. MODERATE Q-VECT CONV COMBINED WITH NNW FLOW 
ACROSS ERN LAKE SUPERIOR SUPPORTING WIND-PARALLEL LES BANDS OF 
MODERATE TO HEAVY IN INTENSITY EAST OF MQT. TIGHT PRES GRADIENT ON 
BACKSIDE OF 992 MB SFC LOW EAST OF LAKE SUPERIOR STILL MAINTAINING 
HIGH GALE TO STORM FORCE WINDS OVER ERN HALF OF LAKE SUPERIOR. 
STRONG WINDS AND MODERATE SNOW RESULTING IN BLIZZARD CONDITIONS OVER 
THE KEWEENAW PENINSULA AND OVER ALGER COUNTY. STATE POLICE HAS 
CLOSED M-28 BETWEEN HARVEY AND WETMORE DUE TO BLIZZARD CONDITIONS 
AND IMPASSABLE ROAD CONDITIONS. 

THE MODERATE 700-300 QVECTOR CONV AND DEEPER MOISTURE WILL LIFT 
SLOWLY EAST WITH THE MOVEMENT OF SFC LOW TONIGHT. AS A RESULT LAKE 
ENHANCED SNOW SHOWERS OVER ERN COUNTIES SHOULD SLOWLY 
DIMINISH...ESPECIALLY OVERNIGHT INTO WEDNESDAY. DRIER AIR WORKING IN 
OVER THE WRN PORTION OF LAKE SUPERIOR AS NOTED ON VIS SATELLITE HAS 
GREATLY DIMINISHED LES OVER FAR WRN COUNTIES LATE THIS AFTERNOON. 
THUS...HAVE DOWNGRADED WARNINGS TO WINTER WX ADVISORIES THIS EVENING 
OVER GOGEBIC...ONTONAGON...BARAGA AND SRN HOUGHTON COUNTIES. WILL 
CONTINUE BLIZZARD WARNINGS INTO THIS EVENING OVER THE KEWEENAW 
PENINSULA AS WINDS GUSTING AOA 35 MPH WILL STILL CAUSE LOW 
VISIBILITY AND TRAVEL DIFFICULTIES THERE. MARQUETTE COUNTY HAS SEEN 
SNOW DIMINISH ACROSS MUCH OF THE AREA BUT LIGHT TO MODERATE LES 
BANDS AND BLOWING SNOW...ESPECIALLY EAST OF MQT...WILL CONTINUE TO 
CAUSE TRAVEL DIFFICULTIES INTO THE EVENING HRS SO KEPT WARNING GOING 
FOR MQT COUNTY. CONTINUED DRYING FROM THE WEST SHOULD LEAD TO 
IMPROVED CONDITIONS FOR MARQUETTE COUNTY WESTWARD LATE TONIGHT INTO 
WEDNESDAY.  

MOST PROLONGED HAZARDOUS CONDITIONS WILL BE FOR COUNTIES EAST OF MQT 
WHERE WINDS GUSTING OVER 40 MPH AND MODERATE LES BANDS WILL 
CONTINUE THE BLIZZARD TO NEAR BLIZZARD CONDITIONS THROUGH TONIGHT 
AND POSSIBLY INTO WED MORNING. CONTINUED THE BLIZZARD WARNING FOR 
ALGER COUNTY THROUGH MUCH OF WEDNESDAY DUE TO OCCASIONAL MODERATE 
SNOW AND EXTREME BLOWING SNOW WITH STRONG NNW WINDS TO 35-40 MPH. AS 
NOTED EARLIER...M-28 CLOSED BTWN HARVEY AND WETMORE DUE TO BLIZZARD 
CONDITIONS. FAVORABLE SNOW GROWTH WITH DGZ WITHIN AREA OF BEST MODEL 
OMEGA WILL ADD TO POOR VISIBILITY AND POTENTIAL FOR GREATER SNOWFALL 
AMOUNTS TONIGHT INTO WED MORNING. MODEL AVG QPF ALONG WITH SLR FM 
20-25/1 SHOULD YIELD 3-6 INCH SNOW AMOUNTS TONIGHT OVER ALGER AND 
NRN SCHOOLCRAFT AND 2-5 INCHES OVER LUCE COUNTY AND SRN SCHOOLCRAFT. 
DEEPER MOISTURE LEAVING THE AREA AND WEAKENING CYCLONIC NNW FLOW 
WILL ALLOW LES TO GRADUALLY TAPER OFF BY WED AFTERNOON OVER ERN 
COUNTIES WITH GENERALLY ADDITIONAL ACCUMS ON WED OF 2-4 
INCHES.

.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 430 PM EST TUE FEB 19 2013

COMPARED TO WHAT WAS OCCURRING OUTSIDE TODAY...THE LONG TERM IS 
GENERALLY QUIET THROUGH MUCH OF THE PERIOD.

LAKE EFFECT SNOW WILL BE SLOWLY DIMINISHING ON WEDNESDAY NIGHT AS
1040MB HIGH PRESSURE OVER NORTHERN ONTARIO CONTINUES TO PUSH A
SURFACE RIDGE OVER LAKE SUPERIOR. SUBSIDENCE ALOFT FROM THIS
HIGH WILL SLOWLY DROP THE INVERSION HEIGHTS OVER THE EASTERN
LAKE FROM AROUND 4KFT AT 00Z THURSDAY TO 2KFT AT 12Z. BUT...THERE
LOOKS TO BE ENOUGH MOISTURE SUB 900MB TO LEAD TO SOME LAKE EFFECT
SNOW IN THE NORTHERLY WIND LOCATIONS OF NORTH CENTRAL UPPER
MICHIGAN. NOT OVERLY IMPRESSED WITH THE THICKNESS OF THE CLOUD
LAYER...ONLY ABOUT 1-2KFT THICK...SO THERE MIGHT NOT BE MORE THAN
VERY LIGHT SNOW OR FLURRIES LATE WEDNESDAY NIGHT INTO THURSDAY
MORNING /MORE NORTHEAST WINDS THEN/ BEFORE THE DRIER AIR LOWERS THE
INVERSION AND SHOVES THE LINGERING CLOUDS TOWARDS THE SURFACE. AT
THAT POINT...IT WOULD LIKELY BE EITHER LOW CLOUDS OR MIX OUT FROM
DIURNAL MIXING INLAND. 

THIS HIGH WILL REMAIN IN PLACE INTO THURSDAY NIGHT...AS A LOW
PRESSURE SYSTEM BEGINS TO EXIT THE CENTRAL PLAINS. MODELS NOT
SHOWING MUCH IN THE WAY OF STRENGTHENING OR WEAKENING AS THIS LOW
MOVES INTO THE GREAT LAKES ON FRIDAY AND THE UPPER GREAT LAKES ON
SATURDAY DUE TO IT BECOMING DETACHED FROM THE STRONGER SOUTHERN
STREAM JET. WITH IT PRECIPITATING ON IT/S WAY UP INTO THIS
AREA...BEING CUT OFF FROM THE GULF MOISTURE...AND RUNNING INTO DRY
AIR FROM THE CANADIAN HIGH...THE IDEA THE MODELS HAVE SHOWN FOR
SEVERAL DAYS OF THE SNOW DIMINISHING AS IT MOVES INTO THE GREAT
LAKES AREA SEEMS REASONABLE. WOULD EXPECT THE LIGHT SNOW TO MOVE
INTO THE AREA ON FRIDAY MORNING AND CONTINUE INTO THE DAY ON
SATURDAY. TOTAL QPF THROUGH THE 36 HOUR PERIOD LOOKS TO BE AROUND
0.25-0.4 INCH. ESTIMATED SNOW RATIOS AROUND 15 TO 1 AT THIS POINT
WOULD LEAD TO 4-6 INCHES OF SNOW OVER MUCH OF THE AREA DURING THAT
PERIOD. THIS WOULD LIKELY BE BELOW ADVISORY CRITERIA...ALTHOUGH SOME
LOCATIONS COULD NEAR THE 3 INCH IN 12 HOUR MARK DURING THE DAY ON
FRIDAY...ESPECIALLY TOWARDS THE WISCONSIN BORDER. 

ONCE THIS SYSTEM DEPARTS TO THE EAST ON SATURDAY NIGHT...HIGH
PRESSURE AND UPPER RIDGING WILL MOVE INTO THE AREA AND LEAD TO A
QUIET AND DRY END TO THE WEEKEND AND LIKELY INTO MONDAY. 850MB TEMPS
SHOULD BE WARMER THAN -10C AND THUS WOULDN/T EXPECT ANY CONCERN FOR
LIGHT LAKE EFFECT ON SUNDAY...ESPECIALLY SINCE WINDS WILL BE BACKING
TO THE SOUTH AND PULLING WARMER AIR OVER THE AREA FOR SUNDAY NIGHT.

ATTENTION THEN TURNS TO THE NEXT WAVE EXITING THE FOUR CORNERS
REGION ON SUNDAY NIGHT AND MOVING TOWARDS THE GREAT LAKES ON MONDAY
INTO TUESDAY. AS IS TRADITIONALLY THE CASE...THE GFS IS ON THE FAST
SIDE WITH THE SYSTEM AND HAVING IT ARRIVE ON MONDAY...WHILE THE
ECMWF IS MORE TOWARDS TUESDAY/WEDNESDAY. THERE ARE ALSO DIFFERENCES
IN THE EXACT TRACK...SO WILL JUST MENTION CHANCE/SLIGHT POPS AT
THIS POINT. 

AS FOR TEMPERATURES...EXPECT TO SEE A GRADUAL WARMING TREND FOR THE
SECOND HALF OF THE WORK WEEK...WITH HIGHS THIS WEEKEND AND INTO THE
FIRST PART OF NEXT WEEK AT OR SLIGHTLY ABOVE NORMAL.
&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 639 PM EST TUE FEB 19 2013

CMX...EXPECT PREDOMINANT LIFR WITH OCNL VLIFR CONDITIONS THIS EVNG 
TO MODERATE TO IFR OVERNGT AS THE STRONG NNW WIND DIMINISHES/BLSN 
SUBSIDES A BIT FOLLOWING SLOW EXIT OF DEEP LO PRES TO THE E. THE 
ARRIVAL OF DRIER AIR/CONTINUED WEAKENING WINDS ON WED WL ALLOW 
CONDITIONS TO IMPROVE TO MVFR.

IWD...EXPECT LIFR CONDITIONS WITH SN/BLSN TO IMPROVE A BIT TO IFR BY 
MIDNGT WITH ARRIVAL OF DRIER AIR/SLOWLY WEAKENING WINDS/SUBSIDING 
BLSN. CONTINUED DRYING/WEAKENING WINDS ON WED WL ALLOW CONDITIONS TO 
IMPROVE TO MVFR.

SAW...EXPECT PREDOMINANT IFR/OCNL MVFR CONDITIONS THRU TNGT TO GIVE 
WAY TO MVFR CONDITIONS ON WED WITH ARRIVAL OF DRIER AIR/SLOWLY 
WEAKENING WINDS/DIMINISHED BLSN.
&&

.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 430 PM EST TUE FEB 19 2013

STRONG WRAPPED UP SFC LOW EAST OF LAKE SUPERIOR WILL HEAD TOWARD 
WESTERN QUEBEC TONIGHT WHILE BEGINNING TO WEAKEN. VERY TIGHT 
PRESSURE GRADIENT PRESENT THROUGH THIS EVENING COMBINED WITH COLD 
AIR ADVECTION AND STRONG WINDS ALOFT WILL MAINTAIN STRONG GALES WITH 
FREQUENT STORM FORCE GUSTS OVER THE EASTERN HALF OF LK SUPERIOR 
THROUGH THIS EVENING. EXTENDED STORM WARNINGS FOR LSZ266 THROUGH 
THIS EVENING. WINDS WILL BE SLOW TO DIMINISH WITH GALES PERSISTING 
OVER CENTRAL AND ERN LK SUPERIOR THROUGH WED. HEAVY FREEZING SPRAY 
WILL CONTINUE THROUGH THURSDAY MORNING. HIGH PRESSURE CROSSING ON 
THURSDAY WILL ALLOW WINDS TO RELAX AND HEAVY FREEZING SPRAY TO 
SUBSIDE. EXPECT EAST WINDS 20-30 KTS ON FRIDAY INTO FRIDAY NIGHT AS 
LOW PRESSURE MOVES IN FROM THE CENTRAL PLAINS. WINDS FOR THE 
UPCOMING WEEKEND NO MORE THAN 20 KTS AS WEAK PRESSURE GRADIENT 
PREVAILS.
&&

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
  WINTER WEATHER ADVISORY UNTIL MIDNIGHT EST /11 PM CST/ TONIGHT 
     FOR MIZ002-004-009-013-084.

  WINTER STORM WARNING UNTIL 5 PM EST WEDNESDAY FOR MIZ007-014-085.

  BLIZZARD WARNING UNTIL 1 AM EST WEDNESDAY FOR MIZ001-003.

  BLIZZARD WARNING UNTIL 5 PM EST WEDNESDAY FOR MIZ006.

  WINTER STORM WARNING UNTIL MIDNIGHT EST TONIGHT FOR MIZ005.

LAKE SUPERIOR...
  HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST /6 AM CST/ THURSDAY 
     FOR LSZ162-240>251-263-265-267.

  GALE WARNING UNTIL 7 PM EST WEDNESDAY FOR LSZ245>251-265-267.

  HEAVY FREEZING SPRAY WARNING UNTIL 1 PM EST THURSDAY FOR LSZ264-
     266.

  STORM WARNING UNTIL 11 PM EST THIS EVENING FOR LSZ266.

  GALE WARNING UNTIL 1 PM EST WEDNESDAY FOR LSZ243-244-264.

  GALE WARNING UNTIL 5 AM EST /4 AM CST/ WEDNESDAY FOR LSZ240>242-
     263.

LAKE MICHIGAN...
  GALE WARNING UNTIL 7 AM EST WEDNESDAY FOR LMZ248-250.

&&

$$

SHORT TERM...VOSS
LONG TERM...SRF
AVIATION...KC
MARINE...VOSS