Area Forecast Discussion
Issued by NWS Marquette, MI

Home | Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary Off
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 280709
AFDMQT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MARQUETTE MI
309 AM EDT SUN JUN 28 2015

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 308 AM EDT SUN JUN 28 2015

UPPER AIR PATTERN CONSISTS OF A 500 MB CLOSED LOW OVER LAKE ERIE
EMBEDDED IN A TROUGH OVER THE LOWER GREAT LAKES...A SHORTWAVE ACROSS
MN AND A STRONG 500 MB RIDGE ACROSS THE ROCKIES THIS MORNING. THIS
SHORTWAVE WILL CONTINUE TO HEAD SSE AND PASS TO THE WEST OF THE AREA
THIS FORECAST PERIOD.

NAM SHOWS SOME WEAK 850-500 MB Q-VECTOR CONVERGENCE REMAINING OVER
THE U.P. THIS FORECAST PERIOD WITH DEEPER MOISTURE REMAINING OFF TO
THE WEST OF THE CWA. GFS AND ECMWF SHOW ABOUT THE SAME THING AS
WELL.

OVERALL...DID NOT MAKE TOO MANY CHANGES TO THE GOING FORECAST AS
LAKE BREEZE CONVERGENCE WILL HELP TO KICK OFF SOME SHOWERS AND
THUNDERSTORMS LATE THIS MORNING INTO THIS EVENING AND THIS WAS
COVERED IN THE FORECAST EXCEPT DID EXTEND LAKE BREEZE CONVECTION
INTO THE EVENING HOURS. KEPT THE POPS IN THE CHANCE CATEGORY.
STUBBORN SHOWER THIS MORNING HAS CONTINUED ACROSS IRON COUNTY AND
HAD TO KEEP ADJUSTING THE ISOLATED POP GRID TO LONGER AS THIS SHOWER
REFUSES TO DISSIPATE. DEFINITELY NOT DIURNALLY DRIVEN...BUT LATEST
TRENDS HAVE BEEN FOR IT TO SHRINK AND HAVE IT DISSIPATING SHORTLY.
MADE VERY FEW CHANGES TO THE TEMPERATURE FORECAST.

.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 334 PM EDT SAT JUN 27 2015

MAIN FCST CONCERNS IN THE MEDIUM/EXTENDED RANGE WL FOCUS ON
POTENTIAL FOR/STRENGTH OF TS ON MON AND POPS AGAIN LATE IN THE
COMING WEEK TOWARD JULY 4TH. AN UPR TROF OVER THE E HALF OF NAMERICA
DOWNSTREAM OF A HI AMPLITUDE RDG OVER THE ROCKIES WL BE THE
DOMINATING WX PATTERN THRU MOST OF THIS FCST PERIOD. ALTHOUGH THERE
ARE HINTS THE PATTERN MAY DEAMPLIFY A BIT LATER NEXT WEEK...TEMPS
OVERALL SHOULD RUN AOB NORMAL THRU THIS FCST PERIOD.

SUN NGT...SHRTWV RESPONSIBLE FOR POPS OVER MAINLY WRN UPR MI ON SUN
IS FCST TO DIG SSEWD INTO IL DURING THE NGT...LEAVING A WEAK SFC RDG
AXIS ACROSS THE UPR LKS. BEST CHC FOR SOME POPS WL BE OVER THE W
EARLY AND AGAIN LATER AT NGT WITH ARRIVAL OF SOME DPVA/DEEP LYR
QVECTOR CNVGC/DEEPER MSTR IN ADVANCE OF NEXT SHRTWV DIGGING SSEWD
TOWARD THE UPR LKS. EXPECT THE LOWER MIN TEMPS OVER THE E...CLOSER
TO LINGERING DRIER AIR/PWAT UNDER AN INCH.

MON/MON NGT...APRCH OF SHRTWV EMBEDDED IN NW FLOW ALF/POCKET OF
LOWER H5 TEMPS ARND -14C/ATTENDANT SFC COLD FNT AS WELL AS DPVA/SOME
DEEP LYR QVECTOR CNVGC/AREA OF DEEPER MSTR WITH H85-5 MEAN RH UP TO
80 PCT WL BRING THE BEST CHC FOR SHOWERS/TS IN THE MEDIUM RANGE...
ESPECIALLY DURING PEAK HEATING ON MON AFTN/EVNG. MAIN LIMITING
FACTOR FOR MORE WDSPRD POPS WL BE LACK OF DEEP MSTR INFLOW THAT WL
BE DISRUPTED BY CIRCULATION ARND DEPARTING SHRTWV/SFC LO TO THE S.
LOOKS LIKE THE BEST CHC FOR HIER POPS WL BE OVER THE W HALF UNDER
AXIS OF HIER H85 THETA E ALREADY IN PLACE NEARBY AT 12Z MON. MODELS
VARY ON THE POTENTIAL FOR STRONGER STORMS. THE 12Z GFS REMAINS THE
MODEL THAT SHOWS THE GREATEST DESTABILIZATION...WITH MUCAPE AS HI AS
2000-2500 J/KG NEAR THE WI BORDER IN THE AFTN UNDER STEEPER MID LVL
LAPSE RATES AS HI AS 6.5-6.8C/KM AND HIER H85 DEWPTS NEAR 10C. THE
MORE CONSERVATIVE 00Z/12Z ECMWF SHOWS MUCAPE NO HIER THAN ABOUT 1000
J/KG NEAR THE WI BORDER. FAIRLY LO WBZ HGT FCST ARND 9K FT AND
POTENTIAL FOR SOME LK BREEZE INTERACTION WITHIN WEAK SFC GRADIENT
FLOW AHEAD OF THE INCOMING COLD FNT INDICATE THE POTENTIAL FOR SOME
LARGE HAIL UNDER THE STRONGER STORMS...ESPECIALLY IF THE HIER CAPE
VALUES ARE CORRECT. LIMITING FACTORS FOR STRONG/SEVERE TS WL BE
DEGREE OF DESTABILIZATION RELATED TO MORE WIDESPREAD CLD COVER AND
WEAKER SFC-6KM SHEAR IN THE 10-20 KT RANGE TO THE E OF RIBBON OF
STRONGER NW FLOW ALOFT FCST OVER MN. SOME OF THE SLOWER MODELS SHOW
SFC COLD FNT NOT PASSING UNTIL CLOSE TO 12Z TUE...SO SOME POPS WL
LINGER THRU MON NGT DESPITE LOSS OF DAYTIME HEATING AND FCST ARRIVAL
OF LARGER SCALE QVECTOR DVGC/SUBSIDENCE BY THE FASTER MODEL RUNS THAT
SHOW QUICKER PASSAGE OF STRONGER SHRTWV.

TUE...THERE COULD STILL BE SOME SHOWERS IN THE MRNG IF THE MODELS
SHOWING THE SLOWER COLD FROPA ARE CORRECT. THEN STEADY NNE WIND
BEHIND DEPARTING COLD FNT AND IN ADVANCE OF SFC HI PRES SINKING INTO
NW ONTARIO IS LIKELY TO BRING SOME LO CLDS/SPRINKLES/DRIZZLE TO
MAINLY THE HIER TERRAIN OF THE NRN TIER INTO THE AFTN BEFORE THE
CLOSER APRCH OF THE SFC HI/EVENTUAL ARRIVAL OF DRIER AIR/DAYTIME
HEATING CAUSE A RETURN OF AT LEAST PARTIAL SUNSHINE BY LATER IN THE
AFTN. EXPECT WELL BLO NORMAL MAX TEMPS NO HIER THAN THE 50S NEAR LK
SUP.

TUE NGT INTO THU...HI PRES WITH PWAT FCST AS LO AS 0.25 INCH WL
BRING A PERIOD OF DRY WX TO UPR MI. FCST H85 TEMPS IN THE 8-10C
RANGE WL ALLOW HI TEMPS IN THE 70 TO 75 RANGE AWAY FM LK MODERATION.
WITH LGT WINDS/MOCLR SKIES UNDER THE SFC HI PRES/DRY AIRMASS...MIN
TEMPS WL FALL WELL INTO THE 40S AND PERHAPS EVEN INTO THE 30S AT
SOME OF THE INTERIOR COLD SPOTS ON TUE AND WED NGTS.

THU NGT INTO JULY 4TH...MOST OF THE LONGER RANGE MODELS SHOW ANOTHER
SHRTWV APRCHG THE UPR LKS LATE IN THE COMING WEEK...WITH PCPN IN
ADVANCE OF THIS DISTURBANCE ARRIVING AS EARLY AS LATE THU. MODEL
CONSENSUS HINTS ATTENDANT COLD FROPA WL OCCUR LATE FRI OR FRI
NGT...WITH COOLER AND DRIER AIR ARRIVING ON SAT/JULY 4TH. BUT
AGREEMENT IS NOT UNIVERSAL...SO WL RELY ON MODEL CONSENSUS FOR NOW.
&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 117 AM EDT SUN JUN 28 2015

VFR CONDITIONS SHOULD PREVAIL AT KIWD/KCMX/KSAW THRU THIS FCST
PERIOD. ONLY POSSIBLE EXCEPTION WILL BE IF SHRA AFFECT ANY OF THE
TERMINALS. DAYTIME HEATING AND RESULTING INSTABILITY MAY TRIGGER
ISOLD/SCT -SHRA/TSRA THIS AFTN/EVENING...MAINLY NEAR LAKE BREEZE
BOUNDARIES. THERE IS THE NORMAL UNCERTAINTY IN LOCATION/COVERAGE OF
CONVECTION...BUT AT THIS POINT...IT APPEARS POTENTIAL IS SUFFICIENT
TO WARRANT A VCSH MENTION AT ALL TERMINALS...THOUGH KIWD/KSAW
PROBABLY HAVE A BETTER POTENTIAL FOR VCSH DUE TO LAKE BREEZE
BOUNDARIES PROGRESSING INTO BETTER INSTABILITY.
&&

.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 308 AM EDT SUN JUN 28 2015

LIGHT WINDS BELOW 20 KNOTS ARE EXPECTED THROUGH THE ENTIRE FORECAST
PERIOD. PATCHY FOG WILL PERSIST ACROSS THE LAKE THROUGH TUE MORNING
AS A RELATIVELY MOIST AIRMASS REMAINS OVER THE REGION.
&&

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

$$

SHORT TERM...07
LONG TERM...KC
AVIATION...ROLFSON
MARINE...07


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