Area Forecast Discussion
Issued by NWS Marquette, MI

Home | Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS63 KMQT 192134
AFDMQT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MARQUETTE MI
434 PM EST WED NOV 19 2014

.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 426 PM EST WED NOV 19 2014

MODERATE TO HEAVY LAKE EFFECT SNOW WILL AFFECT THE WNW TO NW WIND
SNOW BELTS THROUGH THURSDAY AS WELL-BELOW AVERAGE TEMPERATURES
CONTINUE.

LATE THIS AFTERNOON...QUITE A MESS ON RADAR TO SAY THE LEAST. A
PORTION OF A DISORGANIZED MID-LEVEL TROUGH IS CONTINUING TO INDUCE
LIGHT SNOW ACROSS THE EAST HALF OF THE CWA. THE OVERALL SYNOPTIC
FORCING SHOULD CONTINUE MOVING EAST OUT OF THE AREA THROUGH THIS
EVENING. AS THIS OCCURS...LAKE-ENHANCED SNOW BANDS ARE STREAMING OFF
LAKE MI EAST OF US 41...AND A HYBRID SYNOPTIC/MESO LOW IS DEVELOPING
OVER NORTHERN LAKE MI. THESE FEATURES SHOULD MOVE EASTWARD WITH THE
MAIN SYNOPTIC FORCING...BUT AN ADDITIONAL 1-3 INCHES COULD QUICKLY
FALL. THIS IS ESPECIALLY TRUE FOR SE SCHOOLCRAFT COUNTY...WHERE A
SPECIAL WX STATEMENT IS IN EFFECT THROUGH 6PM EST.

A SFC TROUGH THAT HAS BEEN LINGERING ACROSS WESTERN LAKE SUPERIOR
FOR MUCH OF THE DAY IS NOW PROGRESSING EASTWARD AS THE SECOND
PORTION OF THE MID-LEVEL TROUGH BEGINS TO DIG SOUTHEASTWARD ACROSS
THE AREA. THIS HAS RESULTED IN BURSTS OF HEAVY SNOW ALONG THE
WESTERN SHORE DUE TO FRONTAL LIFT AND LAKE INFLUENCE.

TONIGHT AND THURSDAY...MAIN CHALLENGES IN THIS PERIOD WILL BE THE
POSITION AND OVERALL INTENSITY OF LES. AS THE MID-LEVEL TROUGH AXIS
PASSES OVER THE CWA TONIGHT...CAA WILL ALLOW FOR INCREASING COVERAGE
OF LAKE EFFECT SNOW SHOWERS. LAKE-INDUCED EQUILIBRIUM LEVELS
SURPASSING 10KFT COMBINED WITH DECENT ASCENT IN THE DGZ WILL LEAD TO
VERY FLUFFY /20 OR 25 TO 1/ SNOW RATIOS. LES REGIME TYPE ACROSS THE
WEST HAS BEEN DIFFICULT TO PIN DOWN AS SOME WEAK DIRECTIONAL SHEAR
IS BEING INTRODUCED IN THE UPPER THIRD OF THE CLOUD-BEARING WINDS.
HIGH-RES MODEL GUIDANCE IS SPLIT BETWEEN SEVERAL RAGGED TRANSIENT
BANDS AND FEWER STRONGER/STATIONARY BANDS. HAVE OPTED TO LEAN TOWARD
FEWER STRONGER BANDS...BUT AM NOT COMPLETELY CONVINCED THEY WILL
REMAIN STATIONARY ENOUGH ACROSS THE WEST TO PRODUCE WARNING CRITERIA
/8IN IN 12 HRS/ SNOWFALL. HAVE THUS OPTED TO KEEP LES ADVISORY GOING
FOR ALL WESTERN COUNTIES...THOUGH WOULD NOT BE SURPRISED TO SEE
ISOLATED AMOUNTS REACHING WARNING CRITERIA IN THE PORKIES BETWEEN
IRONWOOD AND WHITE PINE. SHADOWING FROM ISLE ROYALE/LESS FETCH
SHOULD KEEP AMOUNTS LOWER ACROSS THE KEWEENAW...THOUGH GUSTY WINDS
AS HIGH AS 35-40 MPH ALONG THE SHORE WILL CREATE SOME BRIEF WHITEOUT
CONDITIONS.

ACROSS THE EAST...LES INTENSITY SHOULD PICK UP LATE THIS EVENING.
SOME OF THE SAME CONCERN ABOUT THE LES REGIME EXISTS ACROSS THE
EAST...BUT ENHANCED CONVERGENCE OFF THE KEWEENAW AND LONGER FETCH
SHOULD FOCUS A MORE PERSISTENT BAND INTO EASTERN ALGER AND NORTHERN
LUCE COUNTIES. WARNING CRITERIA SNOWFALL MAY JUST BE MET
OVERNIGHT...BUT THE POOR CONDITIONS DUE TO STRONGER WINDS JUSTIFY
THE NEED FOR THE LES WARNING.

HEADING INTO THURSDAY...A SECOND SFC TROUGH AXIS WILL PUSH SOUTHWARD
ACROSS THE CWA. THIS SHOULD SHOVE THE EASTERN LES BANDS FARTHER
SOUTHWEST ACROSS THE EASTERN PORTIONS OF THE CWA. ATTM...WOULD NOT
BE SURPRISED TO A STRONG LES BAND SET UP OVER OR JUST EAST OF
MUNISING BY MID MORNING. WITH THE ASSISTANCE OF THE TROUGH AND
CONTINUING CAA...SNOWFALL RATES OF 1 TO 2 INCHES PER HOUR WILL BE
POSSIBLE. ALONG THE WEST...THE SFC TROUGH WILL BE MUCH LESS
INFLUENTIAL. HOWEVER...MODERATE SNOW SHOWERS SHOULD CONTINUE INTO
THE AFTERNOON BEFORE QUICKLY BACKING WINDS BY EARLY EVENING BEGIN TO
PUSH THE LES NORTHWARD.

.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 442 AM EST WED NOV 19 2014

MAIN FCST CONCERNS IN THE LONG TERM ARE ONGOING LES ON THU INTO
EARLY FRI WITHIN THE COLD...CYC NW FLOW LEFT IN THE WAKE OF
DEPARTING LO PRES IN QUEBEC. FOCUS FOR THE WEEKEND WL TURN TO
WARMING TEMPS AND THE POTENTIAL FOR SOME MIXED PCPN SAT/SUN AS A LO
PRES IN THE PLAINS MOVES NNE AND NEAR UPR MI. COLDER AIR AND SOME
LES ARE LIKELY TO RETURN EARLY NEXT WEEK BEHIND THIS LO.

THU...STRONG SHRTWV OVER THE UPR LKS AND ACCOMANYING SFC LO PRES
OVER FAR SW QUEBEC ON THU MRNG ARE FCST TO SHIFT STEADILY TO THE E.
LINGERING DEEP LYR QVECTOR CNVGC OVER THE E ON THU MRNG IS FCST TO
EXIT BY 18Z AND GIVE WAY TO SOME DEEP LYR QVECTOR DVGC UNDER RISING
H5 HGTS UP TO 100-120M IN THE 12Z THU-00Z FRI PERIOD. DESPITE THE
ONSET OF THE NEGATIVE DYNAMICS THAT ARE FCST TO LOWER INVRN BASE W-E
THRU THE DAY...SHARP CYC NW FLOW IN THE PRESENCE OF H85 TEMPS
FALLING TO S LO AS ABOUT -21C WITHIN THE THERMAL TROF MOVING ACRS
THE UPR LKS WL BE FAVORABLE FOR MODERATE TO HEAVY LES. THIS PCPN
SHOULD BE HEAVIEST IN THE MRNG OVER THE E HALF WITH ARRIVAL OF THE
TROF AXIS/SHARP LLVL CNVGC WHILE ABUNDANT MSTR TO H5 IS STILL
PRESENT AND FCST SDNGS SHOW DEEP INSTABILITY WITH EQUILIBRIUM LVL AS
HI AS H55 OR SO. FAVORABLE SN GROWTH RELATED TO SHARP UVV FCST
WITHIN DGZ FM ABOUT 3-6K FT MSL AND A POSSIBLE LK NIPIGON CONNECTION
WL ALSO ENHANCE SN TOTALS. GUSTY NW WINDS WL ALSO RESULT IN
CONSIDERABLE BLSN. ALTHOUGH THE DYNAMIC FORCING WL BE GONE BY 12Z
OVER THE W AND FCST SDNGS SHOW THE ONSET OF MID LVL
DRYING...LINGERING CYC NW FLOW ESPECIALLY IN THE MRNG WL ALLOW FOR
AT SOME MODERATE TO HEAVY LES. BUT AS THE SUBSIDENCE INVRN
STRENGTHENS AND SINKS TOWARD H85 IN THE AFTN... THERE SHOULD BE A
DIMINISHING TREND IN THE SN IN THOSE AREAS. THE BEST CHC FOR DRY WX
WL BE IN THE DOWNSLOPE AREAS OF THE SCENTRAL DURING THE AFTN
FOLLOWING THE EXIT OF THE DEEPER MSTR. HI TEMPS WL RUN WELL BLO
NORMAL AGAIN UNDER THE ARRIVING H85 THERMAL TROF AND MAY SET MORE
DAILY RECORD LO MAX TEMP RECORDS.

THU NGT...SFC HI PRES RDG MOVING E UNDER THE RISING HGTS IS FCST TO
MOVE INTO WI BY 12Z FRI...RESULTING IN A BACKING/MORE ACYC FLOW
ESPECIALLY OVER THE W. THESE BACKING WINDS...ENHANCED BY SFC LAND
BREEZE FLOW...SHOULD ALLOW THE LES OVER THE W TO SHIFT AWAY FM
IRONWOOD AND INTO THE KEWEENAW THRU THE NGT. WHILE THE MORE SLOWLY
BACKING H925 FLOW MAY LIMIT THE RESIDENCE TIME OF THE BANDS OVER THE
E...SOME OF THE MODELS ARE SHOWING A REINFORCING SHRTWV DIGGING SEWD
JUST TO THE NE OF LK SUP. ALTHOUGH THE DPVA/DYNAMIC FORCING IS
PROGGED TO STAY TO THE NE OF UPR MI...A SLOWING OF THE BACKING WIND
TREND ASSOCIATED WITH THIS SHRTWV PASSAGE IN CONCERT WITH INCRSG
LAND BREEZE CNVGC MAY RESULT IN CONTINUED HEAVY LES...ESPECIALLY
NEAR LK SUP E OF GRAND MARAIS. OVER THE INTERIOR W AND SCENTRAL...
EXPECT A VERY CHILLY NGT WITH SOME BLO ZERO MINS WITH PWAT AS LO AS
0.10 INCH. STEADY WNW H925 WINDS UP TO 20 KTS MAY LIMIT THE DIURNAL
TEMP DROP A BIT.

FRI...AS THE UPR TROF OVER ERN CANADA DRIFTS TO THE E...THE FLOW
ALOFT WL TREND MORE ZONAL IN ADVANCE OF AN INCOMING SHRTWV RDG THAT
WL BRING ABOUT 12HR H5 HGT RISES UP TO 150-200M. DESPITE THESE HGT
RISES...DVLPG ISENTROPIC ASCENT IN THE SW FLOW TO THE NW OF SFC HI
PRES MOVING TOWARD THE MID ATLANTIC STATES WL BRING ABOUT INCRSG
MID/HI CLDS. LINGERING LES  OVER THE KEWEENAW AND NEAR LK SUP OVER
THE FAR E SHOULD SHIFT OUT INTO LK SUP.BY 00Z SAT...H85 TEMPS ARE
FCST TO RISE TO NEAR -5C ALONG THE WI BORDER...SO DAYTIME TEMPS
SHOULD MODERATE. BUT FCST HI STABILITY SHOWN ON FCST SDNGS WITH LO
SUN ANGLE INDICATES MAX TEMPS WL REMAIN WELL BLO NORMAL. A STEADY
SSW WIND WL MAKE THE AIR FEEL EVEN COLDER.

FRI NGT THRU SAT NGT...WITH INCRSG ISENTROPIC ASCENT IN THE
STRENGTHENING SW FLOW BTWN HI PRES MOVING OFF THE E COAST AND LO
PRES MOVING ACRS SCENTRAL CANADA...SOME OF THE MEDIUM RANGE MODELS
ARE GENERATING SOME LGT PCPN...MAINLY LATE FRI NGT INTO SAT AFTN
OVER THE ERN CWA WHERE LONGER DURATION OF ISENTROPIC ASCENT WL FAVOR
DEEPER MOISTENING SHOWN ON FCST SDNGS. BUT MARGINAL NATURE OF THE
DEEP MOISTENING JUSTIFIES NO MORE THAN CHC POPS EVEN OVER THE E.
SINCE THE MOISTENING MAY BE RATHER LO BASED AND THIS WARMING SFC
BASED MOIST LYR WL BE WARMER THAN -10C...MAINTAINED MENTION OF
FREEZING DZ LATE FRI NGT THRU SAT NGT WHERE TEMPS REMAIN
SUFFICIENTLY CHILLY. EXPECT A RELATIVELY MODEST DIURNAL TEMP DROP ON
FRI NGT WITH THE MIN TEMPS OCCURRING RELATIVELY EARLY. INCRSG SSW
WINDS AND CLDS ACCOMPANING THE WAD WL PROBABLY CAUSE TEMPS TO RISE
THRU MOST OF THE NGT. TEMPS ON SAT SHOULD RISE ABOVE 32 EVERYWHERE.

SUN THRU TUE...IN GENERAL THE LASTEST LONG RANGE GUIDANCE IS SHOWING
A FARTHER W TRACK FOR SFC LO THAT WL BE DVLPG IN THE MID MS RIVER
VALLEY ON SUN AS ASSOCIATED NEGATIVELY TILTED SHRTWV LIFTS NEWD IN
ADVANCE OF DEEPENING UPR TROF IN THE PLAINS. AS THIS SHRTWV RIDES TO
THE NNE...EXPECT STEADIER PCPN TO DVLP FM THE S ON SUN. SINCE THE LO
IS PROGGED TO TRACK N THRU UPR MI...WITH THE 00Z GFS/ECWMF
INDICATING A TRACK THRU THE CENTRAL CWA...EXPECT THE BULK OF THE
PCPN ON SUN TO FALL AS RA AS H85 TEMPS SURGE TO 2 TO 4C IN THE WARM
SE FLOW AHEAD OF THE NEGATIVELY TILTED SHRTWV. FCST SDNGS INDICATE
THE WARMING BE SFC BASED AS WELL WITH NO SGNFT FREEZING RA. ONCE THE
LO SHIFTS TO THE NNE OF UPR MI...WRAP ARND DEEP CYC W-NW FLOW WL
DRAW COLDER AIR BACK INTO THE UPR LKS AND CHG LINGERING PCPN BACK TO
SN ON MON. LES THEN LOOKS TO BE A GOOD BET ON TUE AS COLDER AIR
SURGES BACK INTO THE AREA ON THE HEELS OF GUSTY NW WINDS LEFT IN THE
WAKE OF THE DEPARTING LO MOVING THRU SE CANADA.
&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1236 PM EST WED NOV 19 2014

LIGHT SNOW AHEAD OF A SURFACE TROUGH CURRENTLY PASSING THROUGH IWD
WILL CONTINUE AT ALL SITES THIS AFTERNOON. THE TROUGH WILL TRACK
EASTWARD ACROSS CMX BY 21Z. LAKE EFFECT SNOW SHOWERS WILL BECOME
MORE WIDESPREAD ALONG AND BEHIND THIS TROUGH...BRINGING SOME
BLSN...MVFR CIGS...AND IFR VIS TO IWD AND CMX. COVERAGE SHOULD BE
WIDESPREAD ENOUGH TO AVOID THE NEED FOR TEMPO GROUPS. EXPECT SHSN TO
CONTINUE THROUGH THURSDAY MORNING...WITH THE POTENTIAL FOR A
MODERATE TO HEAVY SNOW BAND AFFECTING IWD LATE TONIGHT INTO THURSDAY
MORNING. AT SAW...LIGHT SNOW WILL DIMINISH THIS EVENING AND GIVE WAY
TO ISOLATED SHSN UNDER HIGH-END MVFR CONDITIONS THROUGH THE REST OF
THE PERIOD.
&&

.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 426 PM EST WED NOV 19 2014

EXPECT WNW GALES TO 35 KNOTS ACROSS MUCH OF LAKE SUPERIOR THROUGH
TONIGHT AS A SURFACE TROUGH OVER CENTRAL LAKE SUPERIOR THIS AFTERNOON
CONTINUES TO TRACK EASTWARD. WINDS WILL SLOWLY DIMINISH TO 10 TO 20
KNOTS THURSDAY NIGHT WHILE BACKING TO THE SOUTHWEST AS HIGH PRESSURE
PASSES TO THE SOUTH. THEN...AS LOW PRESSURE FORMS OVER THE NORTHERN
PLAINS AND SOUTHERN CANADA...EXPECT SW WINDS TO INCREASE TO 20 TO 30
KNOTS FOR FRIDAY AFTERNOON THROUGH SATURDAY. SOME GALES TO 35 KNOTS
WILL BE POSSIBLE FOR THE WESTERN LAKE DURING THIS TIME. HIGH PRESSURE
WILL QUICKLY MOVE OVER THE AREA SUNDAY AHEAD OF STRONG LOW PRESSURE
FORMING OVER THE UPPER GREAT LAKES SUNDAY NIGHT INTO MONDAY. NW GALES
WILL BE POSSIBLE MONDAY INTO TUESDAY AS THE LOW PASSES NEAR LAKE
SUPERIOR. &&

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
  LAKE EFFECT SNOW WARNING FROM 10 PM THIS EVENING TO 10 AM EST
     FRIDAY FOR MIZ006-085.

  LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST /6 PM CST/ THURSDAY FOR
     MIZ001>004-009-084.

  LAKE EFFECT SNOW WARNING UNTIL 10 AM EST FRIDAY FOR MIZ007.

LAKE SUPERIOR...
  GALE WARNING FROM 10 PM THIS EVENING TO NOON EST THURSDAY FOR
     LSZ248>250-265-266.

  GALE WARNING FROM 10 PM THIS EVENING TO 7 AM EST THURSDAY FOR
     LSZ264.

  GALE WARNING UNTIL 1 AM EST THURSDAY FOR LSZ263.

  GALE WARNING FROM 10 PM THIS EVENING TO 11 AM EST THURSDAY FOR
     LSZ244-245.

LAKE MICHIGAN...
NONE.
&&

$$

SHORT TERM...
LONG TERM...KC
AVIATION...KLUBER
MARINE...KLUBER






USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.