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 251145
AFDMQT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MARQUETTE MI
745 AM EDT MON APR 25 2016

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 422 AM EDT MON APR 25 2016

00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW CONFLUENT NW FLOW
ALF INTO THE UPR LKS BTWN NRN BRANCH CLOSED LO OVER NRN QUEBEC AND A
SRN BRANCH SHRTWV OVER THE WRN GREAT LKS AHEAD OF STRONG SHRTWV
MOVING SLOWLY ENEWD THRU THE NCENTRAL PLAINS. ALTHOUGH MOISTER
AIR...WITH 00Z PWATS AS HI AS 1.16 INCH AT MPX /ALMOST 250 PCT OF
NORMAL/ AND 0.92 INCH AT GRB /190 PCT OF NORMAL/...HAS PUSHED
FARTHER N AHEAD OF THIS SHRTWV AND SFC/H85 LO OVER ERN SDAKOTA...
DRIER AIR ON THE SRN FLANK OF BONE DRY AIRMASS IN ONTARIO /WHERE 00Z
PWAT AT YPL WAS ONLY 0.12 INCH/ MAINTAINED BY PROXIMITY OF THE
CONFLUENCE ZN BTWN THE BRANCHES SLOWED THE ARRIVAL OF HEAVIER RA
THAT HAS BEEN FCST RECENTLY. HOWEVER...LATEST RADAR IMAGERY SHOWS A
BAND OF RA N OF A NEARLY STNRY H85 WARM FNT STRETCHING FM CENTRAL MN
ACRS NCENTRAL WI IS PUSHING NE THRU UPR MI. UPR DVGC IN RRQ OF 120KT
H3 JET MAX OVER SW QUEBEC AS WELL AS SHARP H85-7 FGEN N OF THE ARPCHG
WARM FNT APPEAR TO BE SGNFT FORCING MECHANISMS. BUT THIS BAND IS
RATHER NARROW...WITH DRY SLOTTING IN ADVANCE OF THE APRCHG SHRTWV
CAUSING A SHARP SRN EDGE TO THIS BAND OF HEAVIER RA THAT IS ALREADY
PUSHING N ACRS THE WI BORDER.

MAIN FCST CONCERNS THRU TNGT FOCUS ON POPS/QPF TODAY AHEAD OF SLOWLY
APRCHG SHRTWV AND THEN DRYING TRENDS/POTENTIAL FOR SOME SN TNGT AS
LARGE SCALE SUBSIDENCE/SOMEWHAT COLDER AIR FOLLOW IN THE WAKE OF
SHEARING SHRTWV THRU WI.

TODAY...MODELS IN GOOD AGREEMENT SHOWING BAND OF HEAVIER RA
CONTINUING NE THRU THE CWA BUT TENDING TO DIMINISH AS THE FGEN
FORCING WEAKENS AS THIS BAND MOVES FARTHER N INTO LINGERING DRY AIR
MAINTAINED BY NW FLOW ALF OVER ONTARIO AND AWAY FM NEARLY STNRY FNT
LINGERING IN WI. THEN SOME DRY SLOTTING WILL IMPACT MAINLY THE
SCENTRAL BEFORE DPVA/LARGER SCALE QVECTOR CNVGC IN ADVANCE OF THE
APRCHG SHRTWV ARRIVE W-E AND CAUSE THE PCPN AREA TO EXPAND AGAIN/
INTENSIFY IN THE AFTN. WITH CLD COVER/RA...WL MAINTAIN PREVIOUS FCST
WELL BLO NORMAL MAX TEMPS NOT FAR FM 40.

TNGT...SHRTWV SLIDING ENEWD IS PROGGED TO SHEAR OUT AND MOVE MORE
QUICKLY TO THE E ACRS WI AS IT ENTERS THE UPR CONFLUENCE ZN BTWN THE
NRN AND SRN BRANCHES. WITH DIMINISHING DYNAMIC SUPPORT/MID LVL
DRYING ACCOMPANYING THE SHEARING SHRTWV...EXPECT PCPN COVERAGE/
INTENSITY TO GRDLY DIMINISH. WITH THE ARRIVAL OF COLDER AIR AS THE
LLVL FLOW BACKS MORE TO THE NE...GUIDANCE HINTS THE PCPN WL AT LEAST
MIX WITH SOME SN BEFORE ENDING ESPECIALLY OVER THE NRN TIER AS H85
TEMPS FALL AOB 0C. THE NAM INDICATES SEVERAL INCHES OF WET SN COULD
ACCUMULATE OVER THE HIER TERRAIN OF THE NCNTRL WITH LINGERING SLGTLY
CYC NE UPSLOPE FLOW AIDING COOLING/LIFT. THIS MODEL IS SLOWER THAN
MOST OF THE OTHER GUIDANCE IN SHEARING OUT THE SHRTWV/BRINGING IN
LARGER SCALE QVECTOR DVGC/HOLDING ON TO LLVL CYC FLOW. BUT SINCE
SOME OF THE OTHER HI RES MODELS INDICATE SOME PERSISTENT HIER QPF
OVER THE HIER TERRAIN OF THE NCENTRAL...WL MAINTAIN SOME HIER POPS
IN THIS AREA ALONG WITH A HIER QPF.

.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 349 AM EDT MON APR 25 2016

UPPER AIR PATTERN WILL FEATURE A COLD UPPER LEVEL TROUGH CENTERED
OVER QUEBEC MOST OF THIS WEEK WITH TROUGHING OVER WESTERN CONUS.
UPPER LAKES WILL RESIDE WITHIN CONFLUENT NW FLOW ALOFT ON EDGE OF
EASTERN CANADA TROUGH. RESULT IS HIGH PRESSURE EXPANDING OVER HUDSON
BAY EARLY THIS WEEK WILL PUSH A RIDGE OVER UPPER GREAT LAKES INTO
NEXT WEEKEND. PATTERN WILL LEAD TO DRY WEATHER WITH SEASONABLY COOL
TEMPERATURES. NO REAL SIGNIFICANT WARM UP IS IN SIGHT ATTM. IN FACT
IF ANYTHING THE 7-10 DAY PERIOD JUST BEYOND REACH OF THIS FORECAST
POINTS TO MORE COOLER AND UNSETTLED PATTERN AS TROUGHING OVER
WESTERN CONUS EVENTUALLY MAKES IT TO THE GREAT LAKES. EXTRAPOLATING
CPC DAY 8-14 OUTLOOK MADE ON APRIL 24TH SUGGESTS THAT WARMER AIR MAY
BEGIN TO MAKE ITS WAY OVER GREAT LAKES TOWARD MID MAY AND CPC 3-4
WEEK OUTLOOK GOOD THROUGH MID-LATE MAY SIGNALS A SWITCH TO ABOVE
NORMAL TEMPS. TIME WILL TELL IF THAT DOES INDEED OCCUR.

LINGERING EFFECTS FROM DEPARTING LOW PRESSURE SYSTEM ARE FEW BUT
COULD SHOW UP AS A FEW RAIN/SNOW SHOWERS EARLY ON TUESDAY...MAINLY
FOR UPSLOPE AREAS OF CNTRL CWA. AT THE LEAST...INCREASED SKY COVER
UNTIL LATE MORNING WHEN DRY AIR WITH THE HIGH BUILDING TO THE NORTH
SHOULD ERODE LOW CLOUDS STEADILY FROM NORTH TO SOUTH. SMATTERING OF
MID OR HIGH CLOUDS MAY TRY TO LINGER OVER SOUTHERN CWA...BUT OVERALL
SHOULD TURN INTO A MOSTLY SUNNY DAY FOR ALL CWA.

NO REAL SIGNIFICANT FORECAST ISSUES REST OF THIS WEEK AS THE HIGH
PRESSURE DOMINATES. SKIES SHOULD BE MOSTLY CLEAR AND WINDS NOT
PARTICULARLY STRONG/GUSTY. GRADIENT ONSHORE NORTHEAST WINDS OUT OF
THE HIGH WILL KEEP LAKE SUPERIOR SHORELINE COOLEST WITH DAYTIME
HIGHS MAINLY IN THE 40S. ELSEWHERE...TEMPS SHOULD GRADUALLY RISE
THROUGH THE 50S BY LATE WEEK. PERHAPS MAY SEE LOWER 60S WELL INLAND
FROM THE GREAT LAKES SHORES BY LATE THIS WEEK INTO NEXT WEEKEND...
BUT THAT WOULD ONLY COME FROM AIRMASS MODERATION AS THE OVERALL
TEMPS ALOFT WARM LITTLE. THE COOL AND DRY AIR MASS WITH THE HIGH
POINTS TO GOING ON LOWER END OF GUIDANCE FOR NIGHTTIME LOWS
ESPECIALLY INLAND.

CONSENSUS OF MODELS BRINGS SLIGHT CHANCES BACK OVER UPR MICHIGAN
NEXT SUNDAY. PREVIOUS ECMWF DROVE THOSE RELATIVELY HIGHER POPS...BUT
LATEST RUN HAS TRENDED FARTHER SOUTH WITH SFC-MID LEVEL LOW LIFTING
ACROSS MID MISSISSIPPI RIVER VALLEY. FARTHER SOUTH TREND WITH PRECIP
MAKES SENSE GIVEN THE STRONG/PERSISTENT/DRY HUDSON BAY HIGH THE
SYSTEM WILL BE RUNNING INTO.
&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 744 AM EDT MON APR 25 2016

WITH PERIODS OF RA AND A SHALLOW E FLOW OF CHILLY...MOIST AIR TO THE
N OF A STNRY FNT IN WI...EXPECT IFR/LIFR CONDITIONS TO DOMINATE THE
TAF SITES THIS FCST PERIOD. THE ARRIVAL OF DRIER AIR LATE TNGT AT
CMX WL BRING A RETURN OF COME CLRG AND VFR WX.
&&

.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 349 AM EDT MON APR 25 2016

WITH HIGH PRES BUILDING INTO NORTHERN ONTARIO AND WEAKENING LOW PRES
TRACKING E ALONG A STALLED FRONT S OF UPPER MI...STRONG E TO NE
WINDS WILL BE THE RULE ACROSS LAKE SUPERIOR INTO TONIGHT. OVER THE
WESTERN LAKE WHERE COASTAL CONVERGENCE/FUNNELING ENHANCE E TO NE
WINDS...GALE FORCE WINDS ARE EXPECTED THROUGH THIS EVENING. ACROSS
THE REST OF LAKE SUPERIOR...PLAN FOR WINDS OF 20-30KT. WINDS WILL
SLOWLY DIMINISH LATE TONIGHT/TUE MORNING...BUT MORE SO TUE NIGHT AS
THE NORTHERN ONTARIO HIGH PRES BUILDS INTO THE UPPER LAKES. E TO NE
WINDS GENERALLY UNDER 20KT WILL PREVAIL WED...THOUGH GUSTS TO 25 KTS
MAY OCCUR OVER WRN LAKE SUPERIOR. WINDS WILL DIMINISH TO LESS THAN
20KT THU/FRI ACROSS THE ENTIRE LAKE AS HIGH PRES SETTLES OVER THE
AREA.
&&

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
  GALE WARNING UNTIL 1 AM EDT /MIDNIGHT CDT/ TUESDAY FOR LSZ162-
     263.

LAKE MICHIGAN...
NONE.
&&

$$

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



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