000
FXUS63 KMQT 141745
AFDMQT

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

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 529 AM EDT FRI JUN 14 2013

QUIET ACROSS THE UPPER LAKES THIS MORNING AS HIGH PRESSURE NORTH OF
LK SUPERIOR DRIFTS SOUTH. CLOSEST SHRA/TSRA ARE OVER WESTERN AND
SOUTHWEST MINNESOTA AS JUST UPSTREAM OF MID-LEVEL RIDGE AXIS AND
IN AREA OF ADVANCING H7-H5 MOISTURE/EDGE OF 2-7KM MUCAPE OVER
DAKOTAS. BACK ACROSS THE CWA...WEAK TROUGH IS PRESENT OVER SCNTRL LK
SUPERIOR SO NORTH WINDS HAVE STAYED UP OVR NCNTRL UPR MICHIGAN AND
TEMPS FM MQT TO SAW HAS STAYED IN THE LOWER 50S. MUCH DIFFERENT OVER
INTERIOR WEST CWA WHERE KENTON RAWS SITE HAS DIPPED TO 37 DEGREES AS
OF 07Z. MOST TEMPS ACROSS CWA ARE IN THE 40S. MAIN ISSUE FOR TODAY
IS TEMPS AND EXTENT OF DAYTIME MIXING/LOWERING HUMIDITY. 00Z CWPL
SOUNDING UPSTREAM IN ONTARIO SHOWED LARGE DWPNT DEPRESSIONS THROUGH
H7. FORECAST SOUNDINGS OVR UPR MICHIGAN INDICATE MIXING TO H85-H8
WHICH WILL TAP INTO THE VERY DRY AIR ALOFT. GIVEN NEARLY FULL
SUNSHINE AND BASED ON UPSTREAM OBS TRENDS BENEATH DRY AIR ALOFT
EXPECT MOST AREAS TO SEE DWPNTS FALL AT LEAST 10F FM THOSE THIS
MORNING. RESULT WILL BE VERY LOW RH AWAY FM THE GREAT LAKES SHORES.
WINDS WILL BE LIGHT...MITIGATING ANY FIRE WEATHER ISSUES. LAKE
BREEZES MAY BECOME GUSTY THOUGH. LOWER RH VALUES WILL PERSIST
INTO THE EVENING.

ATTN TONIGHT IS ON H85-H7 MOISTURE ADVECTION PUSHING IN FROM
MINNESOTA AS H85 RIDGE MOVES EAST OF UPPER LAKES. HIGHER H7 DWPNT
ON EDGE OF EML /H65-H5/ MOVING ACROSS NORTHERN PLAINS AND ISENTROPIC
ASCENT 305-310K /H8-H65/ SHOULD SUPPORT AT LEAST ISOLD SHRA MOVING
INTO WEST CWA AFT 06Z AND POSSIBLY AS FAR EAST AS MQT-IMT BY
SUNRISE. ALREADY HAVE SEEN A NARROW BAND OF SHRA/TSRA DEVELOP THIS
MORNING OVER WESTERN MINNESOTA JUST OUT AHEAD OF HIGHER H7 DWPNT.
TSRA CHANCES TONIGHT OVR UPR MICHIGAN ON THE LOWER SIDE BUT NOT
COMPLETELY OUT OF PICTURE AS 2-7KM MUCAPE GRADIENT UPSTREAM AND H7
WINDS FM WEST COULD RESULT IN ISOLD TSRA MOVING INTO WESTERN CWA
LATE TONIGHT. BETTER CHANCES FOR SHRA/TSRA WILL BE FARTHER SOUTH
OVER SOUTHERN MINNESOTA AND INTO WESTERN WISCONSIN ALONG SFC WARM
FRONT/TROUGH AND TIGHT H85 TEMP GRADIENT AND ALSO ON EDGE OF STEEP
H7-H5 LAPSE RATES.

FINALLY...EXPECT SHARP CONTRAST IN TEMPS OVR UPR MICHIGAN FROM
WEST TO EAST TONIGHT. TEMPS OVER FAR WEST WILL LIKELY STAY IN THE
LOW-MID 50S...BUT READINGS OVER THE INTERIOR EAST MAY DROP INTO THE
UPPER 30S AS THAT AREA IS CLOSER TO DEPARTING SFC RIDGE AND DRY AIR
WITH PWATS LESS THAN 50 PCT OF NORMAL.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 529 AM EDT FRI JUN 14 2013

MODELS SHOW A SHORTWAVE MOVING THROUGH NRN MN AND NRN ONTARIO WHICH
WILL PUSH A WARM FRONT ACROSS THE FCST AREA ON SAT. INITIAL PUSH OF
ISENTROPIC ASCENT WILL SHIFT ACROSS THE AREA SAT MORNING INTO EARLY
AFTERNOON...FOLLOWED BY A SURGE OF MIDLEVEL DRYING. WILL SPREAD
DIMINISHING POPS EASTWARD IN THE MORNING/EARLY AFTN AS OVERALL PCPN
POTENTIAL SHOULD DIMINISH WITH PROGRESSION EWD INTO DRY AIR MASS. IN
THE AFTN...QUESTION BECOMES WHETHER THERE WILL BE SUFFICIENT
INSTABILITY FOR CONVECTION TO DEVELOP. NAM AND GFS FCST SOUNDINGS
INDICATE 600-800 J/KG OF CAPE BUT THERE IS ALSO 50-100 J/KG CIN THAT
WOULD PROBABLY PREVENT CONVECTION. HOWEVER...SINCE MODELS STILL SHOW
SHORTWAVE SWINGING THRU NRN MN/ADJACENT NRN ONTARIO IN THE AFTN
AHEAD OF MIDLEVEL LOW OVER SASKATCHEWAN...WILL KEEP SLIGHT CHC POPS
IN FCST FOR LATE AFTERNOON INTO SAT EVENING IN CASE WEAK DEEP LAYER
FORCING FM SHORTWAVE HELPS BREAK CAP AND TRIGGER CONVECTION.

SUN...THERE IS GENERAL MODEL CONSENSUS FOR WEAK SHORTWAVE RIDGING
OVER UPPER MI BTWN DEPARTING SHORTWAVE TO THE E AND SLOWLY
APPROACHING AND OPENING UP CLOSED LOW/SHORTWAVE APPROACHING NW MN.
RESULT SHOULD BE MAINLY DRY WX OVER THE FCST AREA SUN. CONTINUED SCHC
POPS IN THE INTERIOR DURING THE AFTN FOR THE POTENTIAL OF A FEW
DIURNALLY DRIVEN SHRA/TSRA. TEMPS SHOULD RISE WELL INTO THE 70S/LWR
80S WITH A DECENT AMOUNT OF SUNSHINE.

SUN NIGHT/MON...BEST CHC FOR SHRA AND SOME TSTMS LOOKS TO BE SUN
NIGHT INTO MON MORNING AS SHORTWAVE...WHICH WAS THE REMNANT OF THE
MID LEVEL LOW TO THE WNW...MOVES THROUGH THE UPPER LAKES. FOR
NOW...WILL CONTINUE HIGHER CHC POPS FOR SHRA/TSRA.

TUE LOOKS DRY WITH WEAK RDGG OVER THE FCST AREA AS ADVERTISED BY
MEDIUM RANGE MODELS. FOR WED AND THU...MODELS SHOW DIFFERENCES WHICH
MAKE FCST MORE UNCERTAIN. THE CANADIAN MODEL IS MOST AGGRESSIVE
BRINGING A NW FLOW SHORTWAVE THROUGH THE UPPER GREAT LAKES ON WED.
THE ECMWF ALSO HINTS THAT A COUPLE OF WEAK SHORTWAVES MAY MOVE
THROUGH THE AREA WED AFTERNOON INTO THU...WHILE THE GFS SHOWS RDGG
HOLDING INTO WED BUT THEN A NW FLOW SHORTWAVE MOVING THROUGH ON THU.
GIVEN MODEL UNCERTAINTY WILL FOLLOW A MODEL CONSENSUS APPROACH WITH
POPS AND CONTINUE DRY FCST FOR WED BUT WILL BRING IN SLIGHT CHC POPS
FOR SHRA/TSRA WED NIGHT INTO THU.
&&

.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 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 529 AM EDT FRI JUN 14 2013

HIGH PRESSURE OVER LAKE SUPERIOR THROUGH SUNDAY WILL KEEP WINDS
GENERALLY LESS THAN 15 KNOTS. 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...JLA
LONG TERM...VOSS
AVIATION...TITUS
MARINE...MCD