Area Forecast Discussion
Issued by NWS Marquette, MI

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000
FXUS63 KMQT 311926
AFDMQT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MARQUETTE MI
326 PM EDT THU JUL 31 2014

.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 326 PM EDT THU JUL 31 2014

NOT MUCH OVERALL PATTERN CHANGE IN THE LAST 24 HOURS AS AN UPPER LOW
SPINS NEAR JAMES BAY...SENDING SHORTWAVE ENERGY THROUGH THE REGION
ON A FAIRLY REGULAR BASIS. PREDOMINANT SHORTWAVE RIGHT NOW IS JUST
SW OF THE CWA AND HAS SPARKED SOME LIGHT RAIN SHOWERS NEAR LAKE
MICHIGAN WHERE THE LAKE SUPERIOR AND LAKE MICHIGAN BREEZES HAVE
COLLIDED. NOW THAT MUCH OF THE ERN CWA IS BEING DOMINATED BY THE
COOLER AIR BEHIND THE LAKE BREEZES...MOST DIURNAL SHOWERS HAVE
FADED. OTHERWISE...ANOTHER WEAKER SHORTWAVE IS JUST N OF THE MN
ARROWHEAD...BUT NOTHING MORE THAN A CU FIELD IS OCCURRING WITH
THAT...AND NO ADDITIONAL PRECIP DEVELOPMENT IS EXPECTED AS IT MOVES
ACROSS THE CWA THIS EVENING AND TONIGHT.

THAT SHORTWAVE DOES LOOK TO PRODUCE SOME CLOUD COVER OVER THE ERN
CWA TONIGHT...BUT THE REST OF THE CWA WILL SEE MOSTLY CLEAR SKIES.
AS SUCH...LOWS WILL BE IN THE MID 40S TO LOW 50S. COULD SEE SOME FOG
FORM INLAND TONIGHT AS WELL.

YET ANOTHER SHORTWAVE...A LITTLE MORE POTENT THAN THE ONE CURRENTLY
SW OF THE CWA...WILL MOVE AGAIN ACROSS OR SLIGHTLY SW OF THE CWA FRI
AFTERNOON/EVENING. THIS SHOULD ALLOW FOR GREATER DEVELOPMENT OF
CONVECTION THAN WHAT WE HAVE SEEN TODAY DUE TO A PLUME OF HIGHER
MOISTURE THAT WILL MOVE IN. BEST AREA FOR CONVECTION APPEARS TO BE
OVER THE SCENTRAL AND ALONG LAKE MICHIGAN WHERE LAKE BREEZE
CONVERGENCE WILL PROVIDE ADDITIONAL FORCING FOR ASCENT. MLCAPE
VALUES LOOK TO BE 400-800J/KG OVER THE AFOREMENTIONED FAVORED AREAS
AND 0-6KM BULK SHEAR SHOULD BE 20-25KTS. WITH THIS...COULD SEE SOME
STORM ORGANIZATION...BUT SHOULD ONLY BE TO THE POINT OF SOME PEA
SIZED HAIL AT WORST.

.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 426 AM EDT THU JUL 31 2014

DECENT AGREEMENT THAT UPPER LOW CENTERED VCNTY OF JAMES BAY
DEAMPLIFIES BY THIS WEEKEND. OTHER THAN ON SATURDAY THOUGH...TROUGHING
PERSISTS FM WESTERN CANADA ACROSS THE GREAT LAKES THROUGH MOST OF
NEXT WEEK. MEDIUM RANGE MODELS CONTINUE TO POINT TOWARD A COUPLE
PERIODS OF SHRA/TSRA. THE FIRST IS ON FRIDAY AFTN WITH THE SECOND
COMING IN LATER SUNDAY.

THE CHANCES ON FRIDAY ARE MAINLY INLAND OVER THE WEST HALF OF UPR
MICHIGAN. NAM AND ECMWF INDICATE SHORTWAVE/Q-VECTOR CONVERGENCE AND
POCKET OF H7-H5 MOISTURE CROSSES IN THE AFTN OVER NORTHERN WI AND
WESTERN UPR MICHIGAN WHILE GFS AND GEM ARE FARTHER SOUTHWEST WITH
THIS FORCING. TEMPS RISING WELL INTO THE 70S RESULTS IN MLCAPES INTO
INTERIOR WEST CWA PUSHING TOWARD 500J/KG...BUT GREATER INSTABILITY
SHOULD BE RESTRICTED BY AFTN DWPTS ONLY INTO THE UPR 40S/LWR 50S. NAM
DWPNTS INTO THE LOWER 60S SEEM WAY OVERDONE AND RESULT IN MLCAPES
WELL OVR 1000 J/KG. CONTINUED TO HIGHLIGHT HIGHER CHANCE POPS OVER
THE CNTRL CWA WHERE BEST INSTABILITY MATCHES UP WITH LAKE BREEZE
CONVERGENCE. ANY SHOWERS AND STORMS WILL MOVE TO THE ESE AT 20-25 MPH
BASED ON H7 WINDS. LOWER INSTABILITY AND WEAKISH SHEAR UP TO 20 KTS
SHOULD RESULT IN HEAVY DOWNPOURS AS MAIN HAZARD FM ANY STORMS.
YET...SINCE WBZERO HEIGHTS ARE ONLY IN THE 8-9KFT AGL RANGE ANY ISOLD
STRONGER STORMS COULD CERTAINLY PRODUCE PEA SIZED HAIL. LACK OF
STRONGER LARGER SCALE FORCING WILL ALLOW ANY SHOWERS OR STORMS TO END
EARLY ON FRIDAY NIGHT WITH LOSS OF HEATING.

HIGH PRESSURE RIDGE SETTLES ACROSS FOR LATE FRIDAY INTO SATURDAY.
PWATS FALL TOWARD 50 PCT OF NORMAL...INDICATING GOOD RADIATIONAL
COOLING FRIDAY NIGHT WITH LIGHT WINDS. MINS SHOULD FALL INTO LOW TO
MID 40S. SHOULD SEE PATCHY TO AREAS OF FOG IN THE INLAND AREAS.
THIKN THE NAM IS UP TO ITS TRICKS AGAIN ON SATURDAY...BY SHOWING TOO
MOIST OF LOW-LEVELS RESULTING IN TOO HIGH OF MLCAPES. TOOK OUT ANY
MENTION OF SHRA ON SATURDAY EVEN WITH SOME LAKE BREEZE CONVERGENCE.
INLAND AREAS AROUND 80 BASED ON MIXING TO H85 AND ONLY SCT CU.

ATTN LATER SATURDAY NIGHT INTO SUNDAY IS ON STRONGER SHORTWAVE
DROPPING THROUGH IN WNW FLOW ALOFT AS LARGER SCALE TROUGH DEEPENS
YET AGAIN. THE SHORTWAVE AND ASSOCIATED SFC COLD FRONT WORKS ACROSS
UPPER LAKES LATER SUNDAY INTO SUNDAY NIGHT AND IT SEEMS THAT MODELS
ARE MORE LOCKED IN ON MOST SHRA/TSRA OCCURRING DURING THIS TIME.
DRYING TREND THEN DEVELOPS LATE SUNDAY NIGHT INTO MONDAY. EXPECT
MLCAPES TO BE MORE TOWARD 1000J/KG DURING PEAK HEATING ON SUNDAY AS
DWPNTS SURGE UP TO AROUND 60 OVER NORTHERN WI AND PERHAPS WEST CWA
CLOSER TO WI BORDER. DEEP LAYER SHEAR TOWARD 30 KTS ALONG WITH THE
FORECAST INSTABILITY WOULD SUPPORT RISK OF STRONGER STORMS. LOW-LEVEL
CONVERGENCE ALONG THE FRONT MAY BE HELPED ALONG BY LAKE BREEZES AS
WELL. AGREE WITH DAYSHIFT FM WEDNESDAY... THAT COULD SEE SOME STRONGER
STORMS SUNDAY AFTN AND EVENING. BASED ON LACK OF OVERWHELMING EVIDENCE
THOUGH...WILL NOT HIGHLIGHT THIS TIME FRAME IN THE HAZARDOUS WEATHER
OUTLOOK JUST QUITE YET.

FRONT SHOULD BE SOUTH AND EAST OF UPR MICHIGAN TO START THE DAY ON
MONDAY SO EXPECT MINIMAL CHANCES OF SHRA/TSRA MONDAY INTO TUESDAY AS
HIGH PRESSURE BEHIND THE TROUGH EXPANDS ACROSS THE REGION. AFTER
TEMPS NEAR NORMAL THIS WEEKEND...TEMPS EARLY NEXT WEEK WILL RETURN
TO BLO NORMAL VALUES YET AGAIN. MOST NOTABLE COOLING WILL BE OVER
THE NORTHERN U.P. WITH GRADIENT NORTH FLOW OFF LK SUPERIOR.
&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 136 PM EDT THU JUL 31 2014

VFR CONDITIONS EXPECTED THROUGH THE TAF PERIOD. ISOLATED SHOWERS MAY
DEVELOP IN THE NEXT FEW HOURS NEAR SAW ALONG THE LAKE BREEZE WHICH
IS NEAR THE AIRFIELD...BUT COVERAGE WILL BE LIMITED ENOUGH TO KEEP
VCSH IN THE TAF.
&&

.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 326 PM EDT THU JUL 31 2014

WITH A WEAK PRESSURE GRADIENT TYPICAL OF SUMMER DOMINATING THIS
FORECAST PERIOD...EXPECT WINDS UNDER 15 KTS THROUGH MONDAY.

THERE IS THE POTENTIAL FOR PATCHY FOG OVER THE NEXT SEVERAL
DAYS FOR PORTIONS OF LAKE SUPERIOR...BUT DON/T EXPECT ANY
WIDESPREAD DENSE FOG AT THIS TIME.
&&

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

$$

SHORT TERM...TITUS
LONG TERM...JLA
AVIATION...TITUS
MARINE...TITUS






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