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 130909
AFDMQT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MARQUETTE MI
509 AM EDT SUN APR 13 2014

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 508 AM EDT SUN APR 13 2014

WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH NEAR
THE WEST COAST WITH A DOWNSTREAM TROUGH FROM CNTRL CANADA INTO THE
SW CONUS RESULTING IN WSW FLOW FROM THE PLAINS INTO THE NRN GREAT
LAKES. A SHRTWV INTO SW WI NORTH OF A FRONTAL BOUNDARY FROM SW IA
INTO NRN IL AND SRN LOWER MI...AND IN AN AREA OF STRONG LOW LEVEL
MOISUTR INFLOW...SUPPORTED AN AREA OF TSRA OVER SE WI INTO SRN LAKE
MICHIGAN. ANOTHER SIGNIFICANT SHRTWV WAS LIFTING FROM ERN CO/NM
TOWARD THE CNTRL PLAINS. OTHERWISE...ONLY SOME PATCHY DRIZZLE AND
AREAS OF FOG PREVAILED OVER UPPER MI AS MID LEVEL DRYING ABOVE 850
MB HAS SPREAD OVER THE AREA.

TODAY...EXCEPT FOR THE LINGERING FOG EARLY...ESPECIALLY OVER
THE E TO NE UPSLOPE FLOW AREAS IN CNTRL UPPER MI...QUIET WEATHER IS
EXPECTED AS THE MAIN PCPN AREA WILL REMAIN CLOSER TO THE SFC FRONT
NEAR THE IL/W BORDER. NRLY WINDS AND CLOUDS WILL KEEP TEMPS NEAR THE
LOWER END OF GUIDANCE...IN THE LOWER 40S NORTH TO THE UPPER 40S
SOUTH.

TONIGHT...AS THE CNTRL PLAINS SHRTWV MOVES TOWARD THE GREAT LAKES
AND UPPER LEVEL DIV ASSOCIATED WITH THE RIGHT ENTRANCE OF THE
130-140KT JET OVER NRN ONTARIO INCREASES...PCPN WILL EXPAND FROM
FROM NRN WI INTO THE SE HALF OF UPPER MI. THE MODELS SHOW SIGNFICANT
DIFFERENCES WITH HOW FAR TO THE NW THE HEAVIER PCPN SPREADS. THE NAM
WITH THE STRONGEST 700-600 MB FGEN FCSTS HIGHER QPF AMOUNTS TO
AROUND 0.50 INCH INTO CNTRL UPPER MI. THE REGIONAL-GEM...ECMWF AND
GFS KEEP THE HEAVIER PCPN FARTHER TO THE SOUTHEAST. EVEN THOUGH THE
STRONGER MID LEVEL DYNAMICS MAY BE POSSIBLE...SUSPECT THAT THE
MOISTURE INFLOW TO THE NW PORTION OF THE PCPN SHIELD WILL BE LIMITED
BY CONVECTION AND HEAVY RAIN CLOSER TO THE 850 MB FRONT.
NEVERTHELESS QPF AMOUNTS OF 0.20 TO 0.40 INCH EAST OF A LINE FROM
IMT-P53 COULD SUPPORT WET SNOW ACCUMULATIONS OF A FEW INCHES
S COLDER AIR FILTERS INTO THE AREA BRINGING A CHANGEOVER FROM RAIN
TO SNOW BY LATE EVENING. AS TEMPS FALL AT OR BELOW 30F CNTRL...SOME
SLIPPERY AREA MAY DEVELOP ON UNTREATED ROADS.

.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 429 AM EDT SUN APR 13 2014

MOST OF THE IMPACTS FROM THE SYSTEM MOVING ACROSS THE UPPER GREAT
LAKES OCCUR JUST PRECEEDING THE LONG TERM. KEPT HIGHER LIKELY POPS
OVER EAST THROUGH 18Z ON MONDAY AS LAST PUSH OF DIVERGENCE ALOFT AND
LINGERING DEEP MOISTURE MAY GENERATE UP TO 0.10 INCH OF LIQUID PRECIP
IN THE FORM OF AROUND 1 INCH OF WET SNOW. AWAY FM THIS AREA OF
SNOW...HAVE JUST SOME SMALL CHANCES DUE TO UPSLOPE AND SOME MOISTURE
OFF THE GAPS IN WESTERN LK SUPERIOR. DEEP MOISTURE WILL BE WELL TO
THE EAST AND OVERALL WILL BE SEEING LARGER SCALE SUBSIDENCE OVER MUCH
OF CWA BY LATE MONDAY MORNING...SO PROBABLY LOOKING AT FLURRIES OR
VERY LIGHT SNOW SHOWERS.

UNSEASONABLY DEEP TROUGHING WILL SETTLE OVER THE UPPER GREAT LAKES
THE FIRST PART OF THE WEEK. QUITE COOL...WITH H85 TEMPS DOWN TO -18C
ON TUESDAY IN THE AXIS OF THE TROUGHING. EVEN WITH GAPS OF OPEN
WATER OVER ESPECIALLY WEST HALF OF LK SUPERIOR...DO NOT EXPECT MUCH
IN WAY OF LAKE EFFECT LATER MONDAY THROUGH TUESDAY AS AIR IS DRY IN
THE LARGER SCALE. SOUNDINGS FM GFS INDICATE AN INVERTED-V
LOOK...WITH DRY SUB-CLOUD LAYER UP TO THE THIN MOIST LAYER AROUND
H85. BECOMES SLIGHTLY MORE MOIST ON MONDAY NIGHT WITH NIGHTTIME
COOLING...BUT EVEN THIS AFFECT SHOULD BE MINIMAL AS LARGER SCALE
LOW-LEVELS ARE DOMINATED BY ANTICYCLONIC FLOW. MOST NOTEABLE WILL BE
THE COLD...WITH DAYTIME TEMPS ON MONDAY FALLING TO THE UPR TEENS OR
LOWER 20S BY LATE AFTN NEAR LK SUPERIOR AND WITH DAYTIME HIGHS ON
TUESDAY STRUGGLING TO REACH 32 DEGREES...EVEN OVER SCNTRL. NORMAL
HIGHS ON TUESDAY ARE IN THE UPPER 40S NEAR LK SUPERIOR AND INTO THE
LOWER 50S NEAR THE WISCONSIN BORDER. DESPITE INCREASING SUNSHINE BY
AFTERNOON...READINGS ON TUESDAY WILL END UP 20-25 DEGREES BELOW
NORMAL. COOL TEMPS FOR THE NIGHTS AS WELL. MAINLY TEENS EXPECTED
BOTH MONDAY NIGHT AND TUESDAY NIGHT...BUT SINGLE DIGITS POSSIBLE AT
ANY INTERIOR LOCATION ON MONDAY NIGHT THAT CLEARS OUT BRIEFLY AND
ALSO OVER THE EASTERN INTERIOR TUESDAY NIGHT.

LATER TUESDAY NIGHT BUT MORE SO INTO WEDNESDAY AND WEDNESDAY
NIGHT...GFS STILL SHOWING WIDESPREAD MODERATE QPF WHICH WOULD BE
IN THE FORM OF SNOW. GFS HAS SHOWN THIS OVER ITS LAST 5 RUNS BACK TO
00Z ON 12 APRIL. ECMWF RATHER INSISTENT INDICATING WIDESPREAD QPF
WILL BE MORE FROM DAKOTAS ACROSS MINNESOTA AND ACROSS FAR WESTERN
CWA TO LK SUPERIOR. GFS IDEA IS MORE OR LESS SUPPORTED BY LAST
COUPLE GEM-NH RUNS AND 12Z/12 APRIL RUN OF UKMET. DIVING IN MORE IT
APPEARS THAT ALTHOUGH THE GFS AND ECMWF IDEAS LOOK SIMILAR IN THE
LARGER SCALE /LEAD SHORTWAVE INITIALIZING SFC LOW OVER NORTHERN
PLAINS WHILE STRONGER/LARGER SHORTWAVE TROUGH DROPS ACROSS SOUTH
CENTRAL CANADA/ THEY DIFFER IN HOW MUCH PHASING OCCURS BTWN THE TWO
UPPER LEVEL FEATURES. GFS IS SLOWER TO PHASE THUS BRINGS SFC LOW
FARTHER EAST INITIALLY WHILE THE ECMWF PHASES QUICKER AND LIFTS THE
LOW MORE NORTHEAST OVER WESTERN UPR MICHIGAN. LEAD SHORTWAVE WILL
EMERGE OUT OF STRONG SHORTWAVE TROUGH CURRENTLY SHOWING UP WELL ON
WV LOOP OVER THE GULF OF ALASKA. A CONSENSUS OF PRIMARY MODELS
INDICATES HIGH CHANCES OVER CWA...BEGINNING VERY LATE TUESDAY NIGHT
OVER THE FAR WEST...SPREADING ACROSS ALL CWA ON WEDNESDAY...AND
LINGERING INTO THURSDAY MORNING MAINLY EASTERN CWA. PTYPE MAINLY
SNOW...THOUGH ENOUGH LOW-LEVEL WARMING OCCURS OVER SCNTRL BY
WEDNESDAY NIGHT TO RESULT IN MIX OF RAIN/SNOW. MODERATE SNOW
AMOUNTS POSSIBLE...ESPECIALLY NORTH AND WEST CWA PER BLEND OF
LATEST GFS/ECMWF/GEM-NH. MIXING RATIOS 2.5-3 G/KG INDICATE
MODERATE SNOW AMOUNTS AS WELL WEDNESDAY AND WEDNESDAY NIGHT. 00Z RUN
OF ECMWF HAS TRENDED CLOSER TO GFS/GEM-NH IDEAS. WILL LEAVE MENTION
OF THIS SYSTEM OUT OF HWOMQT NOW THOUGH SINCE AS THIS IS THE FIRST
ECMWF RUN TO SHOW SIMILAR SOLUTION TO GFS WITH THIS SYSTEM.

UNCERTAINTY ONLY INCREASES BY FRIDAY AS RECENT RUNS OF GFS BRING
ANOTHER  SHORTWAVE TROUGH AND WRAPPED UP LOW PRESSURE SYSTEM WITH
TOWARD 1 INCH OF QPF ACROSS UPPER LAKES. ECMWF NOT IN AGREEMENT AT
ALL WHILE THE GEM-NH SHOWS SOME IDEA THERE COULD BE SOME PRECIP...
JUST NOT AS STRONG AS GFS. CONSENSUS...WHICH IS WEIGHTED TOWARD GFS
INPUT... GIVES ANOTHER ROUND OF CHANCE POPS FOR FRIDAY. MANUALLY
TWEAKED THOSE DOWN SLIGHTLY...BUT LEFT ALONE OTHERWISE. CRITICAL
THICKNESSES AND FORECASTED TEMPS INDICATE RAIN OR SNOW IS POSSIBLE.
TEMPS FRIDAY AND INTO SATURDAY WILL BE HIGHLY DEPENDANT ON WHETHER
ANY SYSTEM IS IN THE VCNTY. IF SO...TEMPS WILL PROBABLY STAY IN THE
30S WITH THE CLOUDS AND PRECIPITATION. IF NOT...INLAND AREAS AWAY FM
THE LAKES COULD REACH LOWER 50S ONE OR BOTH OF THESE DAYS AS H85
TEMPS ARE WITHIN A FEW DEGREES OF 0C.
&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 125 AM EDT SUN APR 13 2014

WITH AN UPSLOPE E WIND WITHIN SHALLOW COOL AIRMASS N OF STNRY FNT IN
THE LOWER GREAT LKS...EXPECT VLIFR/BLO LANDING MINS TO PERSIST AT
CMX THRU SUNRISE. CONDITIONS AT SAW AND IWD SHOULD DETERIORATE TO
LIFR/IFR RESPECTIVLEY WITH THE SLOW ARRIVAL OF MORE LLVL MSTR IN THE
PRESENCE OF DIURNAL COOLING UNDER MID LVL DRYING AND LGT UPSLOPE
WIND COMPONENT AT SAW/WEAKENING DOWNSLOPE WIND AT IWD. EXPECT
GRADUAL IMPROVEMENT TO MVFR WITH SOME DAYTIME HEATING ON SUN.
DEPENDING ON THE TRACK OF A SFC LO THAT IS FCST TO MOVE FM THE
PLAINS INTO THE GREAT LKS TNGT AND THE LOCATION OF THE NW EDGE OF
THE ACCOMPANYING PCPN AREA...SOME SN/IFR CONDITIONS MAY RETURN TO
SAW THIS EVNG. BUT SINCE MOST OF THE MODELS FCST THE HEAVIER PCPN TO
REMAIN TO THE SE...WL FCST JUST MVFR CONDITIONS FOR NOW.
&&

.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 429 AM EDT SUN APR 13 2014

NORTH TO NORTHWEST GALE FORCE GUSTS TO 35 KNOTS EXPECTED ON MONDAY
IN WAKE OF LOW PRESSURE SYSTEM LIFTING ACROSS SOUTHERN QUEBEC.
PRESSURE GRADIENT WEAKENS BY MONDAY NIGHT TO RESULT IN WINDS LESS
THAN 25 KNOTS BY THAT TIME. WINDS CURRENTLY FORECAST TO STAY MAINLY
BLO 20 KNOTS REST OF THE WEEK...BUT THIS DEPENDS ON WHETHER ONE OR
TWO LOW PRESSURE SYSTEMS IMPACT THE UPPER GREAT LAKES. THE TWO TIME
FRAMES OF INTEREST WOULD BE WEDNESDAY AND WEDNESDAY NIGHT AND AGAIN
ON FRIDAY. IF EITHER OF THESE LOW PRESSURE SYSTEMS DO OCCUR...THEN
WINDS MAY END UP STRONGER THAN CURRENT FORECAST SHOWS.
&&

.HYDROLOGY...
ISSUED AT 429 AM EDT SUN APR 13 2014

RIVER HYDROGRAPHS INDICATE THAT ICE JAMS AT RKLM4/FRDM4 AND EVEN AT
MSQM4 OVER THE LAST FEW DAYS HAVE BROKEN AND RIVERS HAVE LEVELED
OFF. AS OF THIS MORNING...NO IMPACTS HAVE BEEN REPORTED FROM THE ICE
JAMS. SEEMS THAT WITH THE COOLER TEMPS SEEN ON SATURDAY AND THE
COOLER TEMPS EXPECTED FOR MUCH OF THE UPCOMING WEEK /HIGHS 20S TO
30S WITH LOWS WELL BLO FREEZING THROUGH AT LEAST WEDNESDAY/...WE
HAVE PROBABLY REACHED THE END OF THIS INITIAL PERIOD OF SNOWMELT/RUNOFF.
GIVEN ADDITIONAL OPPORTUNITIES FOR PRECIPITATION THIS WEEK AND WITH
4-9 INCHES OF SNOW WATER EQUIVALENT STILL OVER PARTS OF WESTERN AND
CENTRAL UPPER MICHIGAN...THERE WILL BE PLENTY OF WATER AVAILABLE FOR
THE SECOND PERIOD OF SNOW MELT OVER THE NEXT COUPLE OF WEEKS. APPEARS
THAT WARMER TEMPS WHICH COULD START UP THE NEXT PERIOD OF SNOWMELT/RUNOFF
WILL RETURN BY NEXT WEEKEND.
&&

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&

$$

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






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