000
FXUS63 KMQT 142028
AFDMQT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MARQUETTE MI
428 PM EDT FRI JUN 14 2013

.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 425 PM EDT FRI JUN 14 2013

WHILE TODAY IS QUIET WITH ONLY A FEW HIGHER CLOUDS OVER THE CWA AT
NOON...TONIGHT AND SATURDAY ARE MORE COMPLEX GIVEN CONVECTIVE
CHANCES AND RELATED CHALLENGES.

RIGHT NOW THERE IS A SFC HIGH OVER THE CWA...WITH A SFC TROUGH/COLD
FRONT OVER THE DAKOTAS AND CONVECTION BETWEEN THE TWO FEATURES IN
THE WARM AIR/MOISTURE ADVECTION REGIME OVER MN AND FAR WRN WI.
QUESTION IS TO WHAT EXTENT DOES PRECIP SPREAD ACROSS THE CWA TONIGHT
INTO SAT AS THE SFC TROUGH/COLD FRONT MOVES INTO THE WRN CWA AROUND
00Z SUN. THERE ARE THE TYPICAL PROBLEMS WHEN USING MODEL QPF IN
THESE SITUATIONS WHERE THE MODELS DO NOT HANDLE CONVECTIVE FEEDBACK
AND CONVECTIVELY WELL AT ALL. THE 12Z/14 NAMDGN...HIGH RES WRF...AND
GEM /TO NAME A FEW SELECT MODELS/ SHOW HIGHER QPF /PRESUMABLY
CONVECTIVE CLUSTERS/ FORMING OVER THE ARROWHEAD OF MN AND MOVING
INTO THE WRN AND CENTRAL CWA LATE TONIGHT INTO SAT...WHICH MAKES
SENSE WITH EXPECTED STORM MOTIONS. REALLY NOT SURE WHAT EXACTLY IS
GOING TO HAPPEN...BUT CHOOSE TO SIDE MORE WITH 12Z/14
NAM...GFS...AND 00Z/14 ECMWF WHICH SHOW DIMINISHING QPF WITH
EASTWARD MOVEMENT OF THE SYSTEM INTO THE AREA...DUE IN PART TO THESE
MODELS SHOWING MORE CONVECTION BREAKING OUT WELL TO THE S WHICH
WOULD CUT OFF SOME OF THE MOISTURE TRANSPORT INTO THE CWA. THE MORE
SRN FOCUS OF THE BEST CONVECTION MAKES THE MOST SENSE IN A
CLIMATOLOGICAL SENSE. WITH THIS IN MIND...HAVE THE GREATEST POPS
OVER WRN LAKE SUPERIOR TONIGHT...DIMINISHING TO SLIGHT CHANCE BY THE
MID AFTERNOON SAT. AS FOR INSTABILITY...IT SHOULD BE AROUND OR BELOW
500 J/KG ALONG THE WI BORDER SO MAYBE A STRONGER STORM OR TWO AT
BEST...BUT NO SEVERE WEATHER EXPECTED.

WITH PRECIP/CLOUDS MOVING INTO THE WRN CWA TONIGHT...EXPECT WRN
UPPER MI WILL ONLY SEE TEMPS DROPPING INTO THE UPPER 40S TO MID
50S....WITH THE COLDEST TEMPS OVER THE ERN CWA IN THE MID TO UPPER
30S INLAND. HIGHS ON SAT LOOK TO BE IN THE 70S AWAY FROM THE GREAT
LAKES SHORES.

.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 425 PM EDT FRI JUN 14 2013

MOST OF THE LONG TERM AFTER THIS WEEKEND WILL BE DOMINATED BY NW
FLOW INTO THE UPPER GREAT LAKES BTWN A RIDGE DRIFTING FROM THE
ROCKIES TO THE PLAINS AND A BROAD TROF OVER ERN NAMERICA. COOLEST
WEATHER WILL OCCUR EARLY NEXT WEEK BEHIND SHORTWAVE PASSING LATE
THIS WEEKEND. THEN...DESPITE NW FLOW...TEMPS BEYOND MON SHOULD
GENERALLY BE CLOSE TO NORMAL OR EVEN A LITTLE ABOVE NORMAL SINCE THE
ERN TROF WILL NOT HAVE SIGNIFICANT AMPLITUDE INTO THE ERN CONUS.
WHILE THERE WILL BE SOME OPPORTUNITIES FOR PCPN...NW FLOW WILL NOT
SUPPORT WIDESPREAD/SIGNIFICANT RAINFALL.

BEGINNING SAT NIGHT...MID LEVEL LOW OVER SRN SASKATCHEWAN WILL BEGIN
TO WEAKEN/OPEN UP AS IT DRIFTS SE. FARTHER E...SHORTWAVE WILL BE
MOVING ACROSS NRN ONTARIO JUST N OF LAKE SUPERIOR. TAIL END OF WAVE
MAY SUPPORT A FEW SHRA/TSRA MAINLY DURING THE EVENING HRS OVER THE
CNTRL/ERN FCST AREA ON THE LEADING EDGE OF A SURGE OF MIDLEVEL
DRYING. WILL ONLY UTILIZE LOW CHC/SCHC POPS.

ON SUN...FLOW LOOKS RELATIVE BENIGN WITH SUBTLE SHORTWAVE RIDGING
OVER UPPER MI AHEAD OF SLOWLY APPROACHING SHORTWAVE (REMNANT OF MID
LEVEL LOW) APPROACHING NW MN. RESULT SHOULD BE MAINLY DRY WX OVER
THE FCST AREA SUN. HOWEVER...GFS/NAM SHOW MLCAPE INCREASING TO 500
TO PERHAPS UPWARDS OF 1000J/KG IN THE AFTN. WILL MAINTAIN SCHC POPS
IN THE INTERIOR DURING THE AFTN FOR POTENTIAL OF SOME DIURNALLY
DRIVEN SHRA/TSRA. WITH DEEP LAYER SHEAR AROUND 40KT...MIGHT SEE
ISOLD SVR STORMS IF THE HIGHER SIDE OF INSTABILITY RANGE
MATERIALIZES. TEMPS SHOULD RISE WELL INTO THE 70S/LWR 80S WITH A
DECENT AMOUNT OF SUNSHINE.

WILL CONTINUE CHC SHRA/TSRA SUN NIGHT INTO MON MORNING AS SHORTWAVE
MOVES INTO THE UPPER GREAT LAKES. WITH SHORTWAVE SWINGING SE OF
UPPER MI MON...EXPECT SHRA TO END FROM NW TO SE DURING THE DAY WITH
GRADUAL CLEARING FOLLOWING FROM THE W. IT WILL BE A MUCH COOLER
DAY...ESPECIALLY NEAR LAKE SUPERIOR...DUE TO BREEZY N WINDS AND
CLOUDS DOMINATING FOR A GOOD PART OF THE DAY. COOL NIGHT THEN ON THE
WAY FOR MON NIGHT AS HIGH PRES BUILDS INTO THE UPPER LAKES. WITH DRY
AIR MASS (PRECIPITABLE WATER FALLING TO AROUND 50PCT OF NORMAL) AND
WINDS DIMINISHING TO LIGHT/CALM...FAVORED LOWER GUIDANCE FOR MINS
MON NIGHT...ESPECIALLY OVER THE W WHERE SFC HIGH PRES WILL BE
ARRIVING DURING THE NIGHT. MAY SEE SOME OF THE TRADITIONAL COLD
SPOTS FALL INTO THE UPPER 30S.

TUE/WED/THU...UPPER MI WILL BE UNDER NW FLOW. THERE CONTINUES TO BE
SOME HINTS IN MEDIUM RANGE GUIDANCE OF A SHORTWAVE OR TWO DROPPING
DOWN THE RIDGE INTO THE ERN TROF. TYPICALLY...SHORTWAVES IN NW FLOW
DURING THE SUMMER PRODUCE ISOLD/SCT CONVECTION...PARTICULARLY IN THE
AFTN. MODELS CONTINUE TO SHOW INCONSISTENCIES IN TIMING/STRENGTH AND
TRACK OF WAVES...SO CONFIDENCE IS LIMITED IN PINNING DOWN ANY MINOR
PCPN CHANCES. LATEST GUIDANCE SUGGESTS TUE SHOULD BE DRY WHILE
WED/THU MIGHT SEE A FEW SHRA. FOR NOW...WILL NOT INCLUDE EXPLICIT
MENTION OF PCPN GIVEN THE UNCERTAINTY AND PROBABLY WHAT WILL BE LOW
COVERAGE IF PCPN DOES OCCUR.

HEADING INTO FRI...THERE IS CONSIDERABLE DISAGREEMENT BTWN THE GFS
AND ECMWF ON PROGRESSION OF THE RIDGE DRIFTING INTO THE PLAINS WITH
THE ECMWF MUCH SLOWER/MORE AMPLIFIED THAN THE GFS. WILL LEAN TOWARD
THE ECMWF ENSEMBLE MEAN WHICH BRINGS A LESS AMPLIFIED RIDGE INTO THE
GREAT LAKES FRI. WILL ALSO HOLD ONTO DRY WEATHER INTO FRI WITH FRONT
ASSOCIATED WITH PROGRESSING WRN TROF STILL OVER THE WRN PLAINS.
&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 143 PM EDT FRI JUN 14 2013

HIGH PRESSURE AND DRY AIR OVER REGION WILL RESULT IN VFR CONDITIONS
AND GENERALLY LIGHT WINDS THROUGH THIS EVENING. EXPECT INCREASING
CLOUDS LATE TONIGHT WITH JUST A FEW SHOWERS WORKING INTO WESTERN UPR
MICHIGAN /VCNTY OF IWD/. STILL PLENTY OF UNCERTAINTY WITH CONVECTION
LATE TONIGHT INTO TOMORROW.
&&

.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 425 PM EDT FRI JUN 14 2013

HIGH PRESSURE OVER LAKE SUPERIOR THROUGH TONIGHT WILL KEEP WINDS
GENERALLY LESS THAN 15 KNOTS. A WEAK TROUGH OF LOW PRESSURE WILL PASS
OVER LAKE SUPERIOR LATE SATURDAY INTO SATURDAY NIGHT...BUT WINDS WILL
REMAIN RELATIVELY LIGHT. SUNDAY AFTERNOON INTO MONDAY A WEAK LOW
PRESSURE SYSTEM WILL PASS OVER UPPER MICHIGAN...HOWEVER WINDS WILL
STILL REMAIN LESS THAN 15 KNOTS. HIGH PRESSURE WILL RETURN FOR THE
END OF THE FORECAST PERIOD...WHICH WILL KEEP WINDS FAIRLY LIGHT ONCE
AGAIN.
&&

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

$$

SHORT TERM...TITUS
LONG TERM...ROLFSON
AVIATION...TITUS
MARINE...TITUS