Forecast Discussion for MQT NWS Office
000
FXUS63 KMQT 311748
AFDMQT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MARQUETTE MI
148 PM EDT SAT JUL 31 2010

UPDATED AVIATION DISCUSSION FOR 18Z TAFS

.SYNOPSIS...

WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A NW FLOW OVER THE UPPER
GREAT LAKES BTWN A TROF OVER ERN CANADA AND A RIDGE OVER THE
ROCKIES. A WELL-DEFINED SHORTWAVE MOVING THROUGH ONTARIO AND THE
UPPER GREAT LAKES BROUGHT THE HEAVY RAINS TO WEST AND CENTRAL UPPER
MI LAST EVENING AND OVERNIGHT. THE HEAVY RAIN THIS MORNING HAS LEAD
TO AREAS OF FOG OVER THE GREAT LAKES AND PATCHY FOG OVER INLAND
AREAS.
&&

.DISCUSSION...

THE SHORTWAVE NOW OVER THE AREA WILL EXIT LAKE SUPERIOR AND UPPER MI
LATER THIS MORNING.  Q-VECT DIV AND SUBSIDENCE SPREADING IN BEHIND
IT SHOULD PROMOTE DRIER CONDITIONS...ALTHOUGH LINGERING HIGH
DEWPOINTS IN THE LOWER TO MID 60S AND THE EXISTENCE OF A WEAK SFC
BOUNDARY INTERACTING WITH DEVELOPING LAKE BREEZES COULD TRIGGER SOME
ISOLATED CONVECTION THIS AFTERNOON. WILL LEAVE IN SLIGHT CHC TO LOW
CHC POPS.

FOLLOWED A BLEND OF THE BIAS-CORRECTED MAV AND MOS GUIDE WHICH
YIELDED HIGHS IN THE 70S WARMEST OVER INLAND AREAS ALONG THE WI
BORDER.

ANY LINGERING SHRA OVER THE INTERIOR CENTRAL AND EAST WILL DIMINISH
EARLY SATURDAY EVENING WITH LOSS OF DAYTIME HEATING. UPPER HEIGHTS
WILL BEGIN TO RISE AND SURFACE HIGH PRESSURE WILL BUILD INTO THE
AREA. WITH LGT WINDS AND LINGERING LOW LEVEL MOISTURE UNDER SOME MID
LVL SUBSIDENCE AND DRYING...PATCHY FOG WILL BE POSSIBLE SAT
NIGHT.

5H HEIGHTS WILL CONTINUE TO BUILD ACROSS THE UPPER GREAT LAKES ON
SUNDAY AS A S/WV BEGINS TO EJECT OUT OF THE NORTHERN INTERMOUNTAIN
WEST AND INTO THE NORTHERN PLAINS. AS THE CENTER OF SFC HIGH
PRESSURE SHIFTS EAST OF THE GREAT LAKES...WINDS WILL BECOME
SOUTHERLY. NAM DEVELOPS SHOWERS AND UP TO .25 INCH OF QPF OVER
CENTRAL COUNTIES WHILE GFS SHOWS A FEW HUNDREDTHS OVER THE SAME
GENERAL AREA. LOOKING AT THE DRIER GFS MODEL SNDGS AND THE FACT THAT
MID-LVL RDG HEIGHTS WILL BE BUILDING I AM INCLINED TO LEAVE PCPN OUT
OF THE SUNDAY FCST AT THIS TIME. EXPECT PARTLY CLOUDY SKIES AND HUMID
CONDITIONS WITH HIGHS GENERALLY IN THE LOWER TO MID 80S.

SHORTWAVE EMERGING FROM THE NRN ROCKIES AND NRN PLAINS IS PROGGED TO
RIDE OVER THE MID-UPR LVL RIDGE INTO THE UPPER GREAT LAKES LATE
SUNDAY NIGHT AND MONDAY. EXPECT CONVECTION DEVELOPING AT NOSE OF
30-40 KT LOW-LVL JET AND THETA-E RDG OVER THE NRN PLAINS TO SLIDE
INTO UPR MI LATE SUNDAY NIGHT INTO MONDAY. FAVORED HIGHER CHC POPS
OVER THE NRN TIER COUNTIES ALONG AND NORTH OF SFC-850 MB WARM FRONT
WITH LIKELY POPS OVER THE KEWEENAW PENINSULA AND OVER LAKE SUPERIOR.
KEPT IN CHC POPS ACROSS THE FCST AREA MONDAY NIGHT AS SLOW-MOVING
COLD FRONT WITH SYSTEM ADVANCES EAST ACROSS THE REGION. MLCAPE
VALUES INCREASING TO 1000-1500 J/KG AND DEEP LYR SHEAR INCREASING TO
40-45 KT BY MONDAY COULD RESULT IN SEVERE STORM DEVELOPMENT WITH
BOWING SEGMENTS AND DAMAGING WINDS THE MAIN THREAT. SPC CONVECTIVE
OUTLOOK HAS ENTIRE CWA IN SLIGHT RISK FOR DAY 3.

MODELS INDICATE COLD FRONT CLEARING THE AREA BY TUESDAY WITH DRIER
AIR AND HIGH PRESSURE RIDGING INTO THE AREA BY MID-WEEK. HIGH TEMPS
WILL CONTINUE TO RUN SEVERAL DEGREES ABOVE NORMAL INTO MID-WEEK.
&&

.AVIATION /FOR THE 18Z TAF ISSUANCE/...

EXPECT MAINLY MVFR CIGS WITH SCT SHRA TO IMPACT KSAW INTO LATE
AFTN...WITH SKIES SLOWLY CLEARING AT KCMX. LINGERING LOW-LEVEL
MOISTURE WITH DRYING ALOFT SHOULD RESULT IN FOG TONIGHT AT BOTH
SITES. HAVE FCST LIFR CONDITIONS AT KSAW WITH IDEAL RADIATIONAL
COOLING AND WITH RECENT RAINFALL THIS AFTN/EARLY EVENING. AT
KCMX...HAVE WENT WITH MVFR CONDITIONS AS WINDS ARE EXPECTED TO
REMAIN MORE WRLY. LOCAL CLIMATOLOGY AT KCMX FOR JUL/AUG INDICATES
THAT IF WINDS SET UP MORE SE/E TONIGHT...THEN CONDITIONS COULD GO
MUCH LOWER. CONDITIONS TRANSITION BACK TO VFR BY MID MORNING
SUNDAY AT BOTH SITES.
&&

.MARINE /FOR THE 4 AM LAKE SUPERIOR FCST ISSUANCE/...

WITH HIGH PRES GENERALLY DOMINATING THE UPPER GREAT LAKES THROUGH
SUNDAY AFTERNOON...ASSOCIATED WEAK PRESSURE GRADIENT WILL KEEP WINDS
BELOW 20KT. A LOW PRESSURE TROUGH EXPECTED TO MOVE ACROSS THE UPPER
GREAT LAKES MONDAY NIGHT WILL RESULT IN A PERIOD OF STRONGER SOUTH
TO SOUTHWEST WINDS OF 15-25KT LATE SUN NIGHT THROUGH MONDAY.
&&

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

$$


SYNOPSIS...VOSS
DISCUSSION...VOSS
AVIATION...JLA
MARINE...DLG

NWS MQT Office Area Forecast Discussion

Courtesy National Weather Service