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000
FXUS63 KMQT 170841
AFDMQT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MARQUETTE MI
441 AM EDT MON JUN 17 2013

.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 411 PM EDT SUN JUN 16 2013

THE MAIN CONCERN FOR THE SHORT TERM FORECAST WILL BE THE ONGOING
SHOWERS AND THUNDERSTORMS AND ADDITIONAL SHOWERS WITH THE TROUGH
DROPPING SOUTH ACROSS THE AREA TONIGHT. INITIAL CONVECTION WAS OVER
EASTERN UPPER MICHIGAN...WHERE THERE WAS INCREASED MOISTURE FROM THE
FOG EARLIER TODAY AND CONVERGENCE FROM WEAK LAKE BREEZES. THESE
INITIAL SHOWERS HAVE SHIFTED TO THE SOUTHEAST AND OUT OF THE
CWA...BUT ARE SEEING SOME SHOWERS IN CENTRAL UPPER MICHIGAN ALONG
THE LAKE SUPERIOR LAKE BREEZE. THESE SHOWERS HAVE BEEN LIMITED THUS
FAR DUE TO THE DRY MID LEVEL AIR EVEN THOUGH THERE IS STRONG
LOW LEVEL LAPSE RATES AND RAP ANALYZED SB CAPE VALUES OF
500-1000 J/KG. BUT WITH THE INVERTED V LOOK TO THE RAP
SOUNDINGS...ML CAPES ARE STRUGGLING TO GET MUCH ABOVE 250-500 J/KG.
THIS DRY AIR CAN ALSO BE SEEN IN THE DEWPOINTS /UPPER 40S/ AWAY
FROM THE INFLUENCE OF THE GREAT LAKES. THERE HAVE EVEN BEEN SOME
SIGNIFICANT JUMPS IN THE DEWPOINTS OVER THE EASTERN CWA...AS THE
LAKE BREEZES HAVE MOVED IN AND OUT OF SOME OF THE SITES. FARTHER
WEST...A PERSISTENT SHOWER/THUNDERSTORM CLUSTER MOVED INTO WESTERN
GOGEBIC COUNTY OVER THE LAST HOUR AND DID PRODUCE SOME GUSTS UP TO
40KTS EVEN THOUGH THE CLUSTER IS DIMINISHING. THIS ISN/T TOO
UNREASONABLE WITH CURRENT DCAPE VALUES OVER MUCH OF UPPER MICHIGAN
AROUND 800-1000 J/KG AND THE INVERTED V SOUNDINGS. WOULD EXPECT
THIS TO BE THE PRIMARY CONCERN FOR ANY SHOWERS/THUNDERSTORMS LATE
THIS AFTERNOON AND EVENING. FINALLY...ADDITIONAL
SHOWERS/THUNDERSTORMS HAVE BEEN ONGOING JUST NORTHEAST OF LAKE
SUPERIOR...DUE TO ONE PIECE OF SHEARED OFF UPPER LEVEL ENERGY
DROPPING SOUTHEAST ALONG THE TROUGH. THESE SHOWERS WILL CONTINUE
QUICKLY SOUTHEAST AS THE STORM MOTION IS AROUND 40KTS.

THE AREA THAT WILL BRING THE BEST CHANCE FOR SHOWERS IS THE
REMNANT SHORTWAVE FROM THE UPPER LOW THAT WAS IN CENTRAL
SASKATCHEWAN YESTERDAY. THIS SHORTWAVE HAS STARTED TO MOVE TOWARDS
THE CANADA/ND/MN BORDER AND HAS SPARKED SHOWERS AND THUNDERSTORMS
ALONG THE SURFACE TROUGH WHERE THERE IS DEEPER MOISTURE. WITH THE
STORM MOTION TO THE SOUTHEAST AROUND 30-35KTS AND THE TROUGH SLOWLY
SAGGING SOUTHEAST...WOULD EXPECT THOSE SHOWERS TO MOVE SOUTHEAST
ACROSS WESTERN/CENTRAL UPPER MICHIGAN LATE THIS AFTERNOON AND INTO
THE EVENING HOURS. NOT ENTIRELY CONFIDENT ON THE EASTERN CWA...AS
IT WILL DEPEND ON THE THUNDERSTORMS CURRENTLY MOVING SOUTHEAST
FROM THUNDER BAY AND HOW FAR SOUTHEAST THEY WILL MAKE IT BEFORE
DIMINISHING. WILL HAVE LOWER POPS THAN OVER THE WEST...BUT STILL
IN THE LOW END CHANCE CATEGORY. AN EARLIER UPDATE COVERED THE
TIMING WELL OVER THE WEST AND HAVE JUST MADE MINOR TWEAKS TO
MATCH THE CURRENT CONDITIONS...WITH MOST AREAS IN THE HIGHER REACHES
OF THE SCATTERED/CHANCE CATEGORY. THINK THERE IS A DECENT SHOT MOST
LOCATIONS WILL SEE RAIN...BUT THE COVERAGE/TIMING WOULD BE BETTER
REFLECTED IN THE SCATTERED WORDING. AS MENTIONED ABOVE...THE DRY
AIR AND LIMITED INSTABILITY WILL BE THE MAIN LIMITING FACTORS TO
THE THUNDERSTORMS AND THEIR SEVERE POTENTIAL. BEST THREAT WILL BE
WEST-SOUTHWEST OF THE CWA WHERE THE 850-700/500MB LAPSE RATES ARE
THE STEEPEST...BUT THERE COULD BE SOME STRONGER STORMS OVER THE
SOUTHWEST THIRD OF THE CWA. HAIL POTENTIAL WILL BE LIMITED DUE TO
THE LIMITED INSTABILITY AND TALL/SKINNY CAPE. AS MENTIONED
ABOVE...GUSTY WINDS WILL BE THE BIGGEST THREAT OVER THE SW
HALF OF THE CWA...AS THEY HAVE THE STEEPER MID LEVEL LAPSE
RATES...COMBINED WITH THE DRY LOW LEVELS TO PRODUCE THE HIGHER
DCAPE VALUES.

THEN...AS THE SHORTWAVE TRACKS SOUTHEAST INTO NORTHWEST WISCONSIN
TONIGHT AND THE REST OF NORTHERN WISCONSIN ON MONDAY
MORNING...WOULD EXPECT SCATTERED SHOWERS TO CONTINUE THROUGH THE
NIGHT OVER THE SOUTHWEST HALF OF THE CWA. THAT IS ALSO WHERE
THE BEST 850-500MB Q-VECTOR CONV IS LOCATED EVEN THOUGH THE DEEPER
MOISTURE IS OVER EASTERN UPPER MICHIGAN. HAVE SLOWLY DIMINISHED THE
THUNDER THREAT OVERNIGHT AND INTO MONDAY MORNING TO BE OVER THE
SOUTHERN PART OF THE CWA...WHERE THE BETTER FORCING IS LOCATED. WILL
HOLD ON TO SOME LIGHT RAIN SHOWERS OVER NORTHERN UPPER MICHIGAN
OVERNIGHT TONIGHT AND INTO TOMORROW MORNING...AS LOW LEVEL
CONVERGENCE INCREASES WITH THE WINDS SHIFTING TO THE
NORTH-NORTHEAST. WITH DECENT MOISTURE BELOW 10KFT AS THAT
CONVERGENCE OCCURS...THINKING THERE WILL BE ENOUGH TO PRODUCE SOME
SHOWERS...ESPECIALLY OVER SOME OF THE HIGHER TERRAIN LOCATIONS OF
NORTH CENTRAL UPPER MICHIGAN WHERE THE WINDS BECOME UPSLOPE FOR A
PERIOD OF TIME.

THE LARGER SCALE FORCING SHOULD DEPART THE SOUTHWEST AND SOUTH
CENTRAL CWA AROUND DAYBREAK AND THEY WILL BE LEFT WITH ANY SHOWERS
DROPPING SOUTH ALONG THE ENHANCED CONVERGENCE. BEHIND THE
TROUGH...LOW CLOUDS SEEN IN CENTRAL ONTARIO/MANITOBA THIS MORNING
WILL MOVE SOUTH ACROSS THE CWA LATE TONIGHT INTO TOMORROW MORNING.
MODELS STRUGGLING WITH HOW LOW THE CLOUDS WILL BE...BUT EITHER WAY
A CLOUDY START TO THE WORK WEEK IS EXPECTED. CANADIAN HIGH PRESSURE
IS EXPECTED TO BUILD OVER THE AREA ON MONDAY AFTERNOON...BRINGING
DRIER AIR AND SUBSIDENCE TO THE AREA IN THE AFTERNOON. THIS WILL
PRODUCE DECREASING CLOUDS FROM NORTH TO SOUTH. HIGHS WILL BE MUCH
COOLER TOMORROW...WITH 60S IN MOST LOCATIONS EXCEPT NEAR LAKE
SUPERIOR WHERE NORTHERLY FLOW OFF THE LAKE WILL KEEP HIGHS IN THE
UPPER 50S.

.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 411 PM EDT SUN JUN 16 2013

THROUGH THE MIDDLE OF THE WEEK...NW FLOW WILL PREVAIL INTO THE UPPER
GREAT LAKES BTWN A RIDGE DRIFTING FROM THE ROCKIES TO THE PLAINS AND
A BROAD TROF OVER ERN NAMERICA. AS THE RIDGE SHIFTS TO THE
MISSISSIPPI VALLEY/GREAT LAKES LATE WEEK...IT WILL LOOSE AMPLITUDE
AS SHORTWAVE ENERGY EJECTING E FROM A TROF OVER THE NW CONUS BEGINS
TO SUPPRESS THE RIDGE. THE NW FLOW EARLY ON WILL SUPPORT DRY WEATHER
FOR UPPER MI. MOVING INTO THE LATE WEEK PERIOD...PATTERN SHOULD
BECOME ACTIVE WITH DECENT PCPN PROSPECTS AS SHORTWAVES TRACK E
ACROSS THE NRN PLAINS TO THE GREAT LAKES. AS FOR TEMPS...COOLEST
WEATHER WILL OCCUR OVER THE NEXT DAY OR TWO BEHIND SHORTWAVE PASSING
TONIGHT/MON. THEN...DESPITE NW FLOW...TEMPS THRU THE MIDWEEK PERIOD
SHOULD BE CLOSE TO NORMAL OR EVEN A LITTLE ABOVE NORMAL SINCE ERN
TROF WILL NOT HAVE SIGNIFICANT AMPLITUDE INTO THE ERN CONUS...
RESULTING IN COOLER AIR STAYING E AND NE OF THE AREA. TEMPS LATE
WEEK INTO THE WEEKEND WILL BE ABOVE NORMAL WITH WARMER/MORE HUMID
CONDITIONS. COULD BE UNCOMFORTABLY HUMID FOR A DAY OR TWO.

BEGINNING MON NIGHT...A CHILLY NIGHT IS ON THE WAY AS HIGH PRES
BUILDS INTO THE UPPER LAKES. WITH VERY DRY COLUMN (PRECIPITABLE
WATER 30-50PCT OF NORMAL) AND WINDS DIMINISHING TO LIGHT/CALM...WILL
CONTINUE TO FAVOR THE LOW END OF MODEL GUIDANCE FOR MIN TEMPS...
ESPECIALLY OVER THE W WHERE SFC HIGH PRES CENTER WILL BE ARRIVING
DURING THE NIGHT. WITH IDEAL RADIATIONAL COOLING CONDITIONS...THERE
IS A GOOD POTENTIAL FOR SOME FROST IN THE USUAL COLDER AREAS.
SOME OF THE TRADITIONAL COLD SPOTS COULD FALL TO NEAR FREEZING.
RECORD LOW FOR NWS MQT SITE ON THE 18TH IS 38F. NOT OUT OF THE
QUESTION THAT RECORD COULD BE TIED OR BROKEN.

SFC HIGH PRES WILL BE SETTLED OVER THE UPPER LAKES TUE...PROVIDING A
DRY/PLEASANT MID JUNE DAY WITH ABUNDANT SUNSHINE UNDER LINGERING
VERY DRY COLUMN. LAKE BREEZES WILL BE THE RULE...KEEPING LAKESIDE
LOCATIONS COOLER IN THE AFTN. GIVEN AVBL DRY AIR TO MIX DOWN...DWPTS
SHOULD FALL TO THE MID 30S...POSSIBLY LOWER...IN THE INTERIOR...
RESULTING IN MIN RH DOWN AROUND 25PCT. WOULDN`T BE SURPRISED TO SEE
SOME LOCATIONS FALL TO AROUND 20PCT. FORTUNATELY...LIGHT WINDS WILL
KEEP FIRE WX CONCERNS IN CHECK.

MEDIUM RANGE GUIDANCE HAS AND STILL CONTINUES TO HINT THAT A
SHORTWAVE WILL DROP SE...PASSING JUST N OF UPPER MI LATE WED/WED
NIGHT. GIVEN THE FAIRLY CONSISTENT SIGNAL FROM ALL MEDIUM RANGE
GUIDANCE...IT STILL APPEARS THERE MAY BE SOME PCPN AT SOME POINT
LATE WED/WED NIGHT. NOTHING MORE THAN SCHC/LOW CHC POPS ARE
WARRANTED SINCE BETTER FORCING PASSES BY TO THE N AND SINCE COVERAGE
WILL BE LOW IF PCPN DOES OCCUR. IF WAVE IS FASTER AND ARRIVES DURING
PEAK HEATING WED...PCPN CHC WILL BE GREATER...BUT WOULD STILL NOT
EXPECT ANYTHING MORE THAN SCT COVERAGE.

ON THU...THERE IS THE POTENTIAL FOR SUBTLE BOUNDARY ASSOCIATED WITH
THE SHORTWAVE PASSING BY THE AREA WED NIGHT TO HANG UP OVER/NEAR
UPPER MI...AND THAT COULD BE THE FOCUS FOR SOME CONVECTION THU AFTN.
MAINTAINED SCHC/LOW CHC POPS IN FCST.

AS MENTIONED EARLIER...THE LATE WEEK PERIOD INTO THE WEEKEND COULD
BECOME ACTIVE AS SHORTWAVES TRACK ACROSS THE NRN CONUS TO THE GREAT
LAKES...SUPPRESSING THE RIDGE THAT WAS SHIFTING ACROSS THE PLAINS
TOWARD THE AREA. SIGNAL LOOKS STRONG ENOUGH TO WARRANT AT LEAST MID
RANGE CHC POPS FOR SHRA/TSRA FOR PORTIONS OF FRI/SAT. SFC HIGH PRES
MAY BEGIN TO BUILD S TOWARD THE UPPER LAKES SUN IN THE WAKE OF A
SHORTWAVE SWINGING ACROSS HUDSON BAY/QUEBEC...SO PCPN CHANCES MAY
DIMINISH ON SUN. OVERALL...THERE APPEARS TO BE DECENT POTENTIAL THAT
MOST LOCATIONS WILL SEE SOME RAIN AT SOME POINT BTWN FRI AND SUN.
&&

FOR THE EXTENDED...
ISSUED AT 440 AM EDT MON JUN 17 2013

MODELS ARE STILL IN FAIRLY GOOD AGREEMENT IN THE PLACEMENT OF A
MID/UPPER LEVEL RIDGE OVER THE PLAINS THROUGH THE DAY FRIDAY...WITH
THE ASSOCIATED SURFACE HIGH PRESSURE DOMINATING THE UPPER GREAT
LAKES REGION THROUGH SATURDAY. THIS WILL KEEP DRY WEATHER WITH
PREDOMINATE LIGHT N/NERLY WINDS THROUGH THIS TIME PERIOD.
SUNNY/PARTLY CLOUDY SKIES WILL KEEP TEMPERATURES FAIRLY STEADY /AT
OR SLIGHTLY BELOW NORMAL/...WITH COOLEST TEMPERATURES NEAR LAKE
SUPERIOR DUE TO NORTHERLY WINDS OFF THE LAKE.

MODEL CONSENSUS ALSO SHOWS A SHORTWAVE DEVELOPING ON THE BACKSIDE OF
THE RIDGE...HOWEVER DISAGREEMENTS COME IN TO PLAY ON THE PATH THIS
SHORTWAVE WILL TAKE. GFS AND GEM SOLUTIONS HAVE THE SHORTWAVE
DEVELOPING OVER THE PLAINS ON SATURDAY...THEN GETTING PUSHED TO THE
SOUTHEAST UNDER THE INFLUENCE OF THE HIGH PRESSURE RIDGE AND DRY AIR
ALREADY IN PLACE. THIS SOLUTION SEEMS THE MOST REASONABLE. ECMWF
SOLUTION ON THE OTHER HAND CONTINUES TO BE MORE AGGRESSIVE WITH THIS
SYSTEM...MOVING IT NORTHEAST ALONG THE BACKSIDE OF THE RIDGE AND
REACHING THE UPPER GREAT LAKES BY SATURDAY AFTERNOON. WITH THE
GFS/GEM...UPPER MI SHOULD REMAIN DRY. HOWEVER WILL KEEP SLIGHT
CHANCES NEAR THE WI BORDER SATURDAY AFTERNOON...SPREADING FURTHER
INLAND SATURDAY NIGHT AND SUNDAY TO ACCOUNT FOR ECMWF SOLUTION. WITH
THE INCREASE IN CLOUD COVER ASSOCIATED WITH THIS SYSTEM...EXPECT LOW
TEMPERATURES SAT NIGHT TO BE SLIGHTLY WARMER THAN PREVIOUS...BUT
STILL HOVERING ON THE FREEZING LINE...SO SNOW COULD MIX IN WITH RAIN
IN AFFECTED AREAS. PRECIP SHOULD DISSIPATE BY SUNDAY NIGHT AS
SHORTWAVE MOVES TO THE SOUTHEAST AND HIGH PRESSURE BEGINS TO BUILD
IN FROM CANADA THROUGH THE DAY MONDAY.

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 141 AM EDT MON JUN 17 2013

AN UPPER LEVEL DISTURBANCE WILL PRODUCE SHOWERS FOR KIWD AND POSSIBLY
KSAW OVERNIGHT. LIFR CLOUD DECK HAS ALREADY FORMED AT KCMX AND IT
LOOKS LIKE IT/S BEGINNING TO FORM AT KSAW IN UPSLOPE NE FLOW SO WILL
INCLUDE LIFR CLOUDS IN AT BOTH SITES FOR THE OVERNIGHT. BELIEVE IFR
TO LIFR CLOUD DECK WILL ALSO FORM AT KIWD BY 10Z AS WINDS SHIFT
TO ONSHORE NE DIRECTION. LOW CLOUDS WILL GRADUALLY LIFT BY LATE MON
MORNING BRINGING VFR CONDITIONS TO ALL TAF SITES.
&&

.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 411 PM EDT SUN JUN 16 2013

WINDS ARE EXPECTED TO STAY BELOW 20KTS THROUGH THE PERIOD. A TROUGH
WILL DROP SOUTH ACROSS LAKE SUPERIOR THIS EVENING...LEADING TO WINDS
SHIFTING TO THE NORTH TONIGHT. AS THE TROUGH CONTINUES SOUTHEAST ON
MONDAY...HIGH PRESSURE WILL BUILD OVER THE UPPER GREAT LAKES AND
REMAIN THROUGH WEDNESDAY. A WEAK TROUGH WILL THEN APPROACH THE AREA
FROM THE NORTHWEST FOR THURSDAY. THERE IS A POCKET OF FOG OVER
EASTERN LAKE SUPERIOR /NEAR AND EAST OF GRAND MARAIS MI/ THAT HAS
BEEN DIMINISHING AND MOVING AROUND TODAY. WOULD EXPECT THE DRY AIR
TO CONTINUE TO EAT AWAY AT IT THIS EVENING...BUT THERE IS SOME
CONCERN IT COULD EXPAND WITH RAIN OCCURRING OVER CENTRAL LAKE
SUPERIOR THIS AFTERNOON/EVENING AND LINGER THROUGH THE NIGHT. IF FOG
DOES LINGER TONIGHT...IT WILL CLEAR OUT MON MORNING AS MUCH DRIER AIR
SURGES S INTO THE UPPER LAKES.
&&

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

$$

SHORT TERM...SRF
LONG TERM...ROLFSON
EXTENDED...
AVIATION...07/JV
MARINE...SRF