000
FXUS63 KMQT 160542
AFDMQT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MARQUETTE MI
142 AM EDT SUN JUN 16 2013

.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 432 PM EDT SAT JUN 15 2013

WEAKENING UPPER RIDGE AXIS IS STILL OVER THE WESTERN GREAT
LAKES...WHILE A LARGE UPPER LOW IS SPINNING OVER CENTRAL
SASKATCHEWAN. THERE AREA A COUPLE SUBTLE DISTURBANCES ROUNDING THE
RIDGE. THE FIRST ONE IS CURRENTLY EXITING EASTERN UPPER MICHIGAN.
THIS WAVE COMBINED WITH BROAD WARM AIR ADVECTION TO PRODUCE
THE SHOWERS THIS MORNING OVER THE WEST AND THEN THE DIMINISHING
SHOWERS OVER THE EAST THIS AFTERNOON. THE NEXT WAVE IS CURRENTLY
ASSOCIATED WITH THE CONVECTION IN NORTHERN IOWA AND SOUTHERN
MINNESOTA AND MOVING TO THE EAST-NORTHEAST. AT THE SURFACE...A
TROUGH IS CURRENTLY STRETCHING SOUTH ACROSS EASTERN MINNESOTA FROM
THE LOW IN CENTRAL SASKATCHEWAN. POCKET OF MLCAPE VALUES AROUND
1000 J/KG IS LOCATED AHEAD OF THIS TROUGH IN WESTERN WISCONSIN AND
STARTING TO NOSE NORTHEAST INTO WESTERN UPPER MICHIGAN. SHOWERS AND
THUNDERSTORMS HAVE STARTED TO DEVELOP NORTH OF THE TWIN CITIES...AS
HINTED AT BY MORNING RUNS OF THE HRRR...AND HAVE BEEN LIFTING
NORTHEAST.

FOR THE REST OF THIS AFTERNOON AND TONIGHT THE FORECAST DEPENDS ON
TWO FEATURES...THE TROUGH MOVING THROUGH THE U.P. THIS EVENING AND
THE SHORTWAVE ASSOCIATED WITH THE DECAYING CONVECTION IN SOUTHEAST
MN. THEY BOTH SEEM TO BE INTERACTING OVER THE LAST COUPLE OF HOURS
WITH THE DEVELOPMENT OF THUNDERSTORMS NORTH OF THE TWIN CITIES AND
INTO WEST CENTRAL WISCONSIN. AS INDICATED BY THE HRRR THIS
MORNING...WOULD EXPECT THESE THUNDERSTORMS TO CONTINUE DEVELOP AND
PUSH NORTHEAST INITIALLY BEFORE THE STORM MOTIONS TAKE THEM MORE
EASTERLY AS IT ROUNDS THE RIDGE. ML CAPES SHOULD CONTINUE TO PUSH
NORTHEAST TOWARDS THE WISCONSIN BORDER...AS THE LOW CLOUDS BEGIN TO
THIN AND INCREASE HEATING. THE ONE CONCERN WILL BE THE THICKENING
HIGH CLOUDS ON THE NORTH SIDE OF THE CONVECTION MAY BE ENOUGH TO
LIMIT THE NORTHWARD EXTENT OF THE INSTABILITY. WITH THE SHORTWAVE
ALSO ROUNDING THE RIDGE...THAT SHOULD FOCUS THE BEST FORCING ACROSS
CENTRAL WISCONSIN. THEREFORE...WOULD EXPECT THE BEST CHANCE FOR
SHOWERS AND THUNDERSTORMS LATE THIS AFTERNOON AND EVENING OVER THE
SOUTHERN HALF OF THE CWA...ESPECIALLY NEAR THE WISCONSIN BORDER
WHERE THE BEST INSTABILITY WILL BE LOCATED AND STORM MOTION WOULD
TRACK THE THUNDERSTORMS. AT THIS POINT...WOULD EXPECT HEAVY RAIN TO
BE THE MAIN THREAT SINCE NCAPE SHOULD REMAIN BELOW 0.1 AND DCAPE
VALUES STRUGGLE TO RISE ABOVE 700 J/KG AS THE LOW CLOUDS OVER THE
SOUTHWEST DISSIPATE.

FARTHER NORTHWEST...THE UPPER LOW SPINNING IN CENTRAL SASKATCHEWAN
WILL LIKELY SPARK SOME SHOWERS AND THUNDERSTORMS ALONG THE
MN/ND/CANADA BORDER THIS AFTERNOON WHICH WILL TRACK EAST THIS
EVENING. WITH THE LOSS OF DIURNAL HEATING...WOULD EXPECT THEM TO
DIMINISH AS THEY APPROACH NORTHERN LAKE SUPERIOR. BUT WITH THE
CLOSE PROXIMITY OF THE UPPER LEVEL SHORTWAVES...DEEPER MOISTURE AND
STEEPER LAPSE RATES...WILL HOLD ONTO SLIGHT CHANCE POPS AS THAT
MOVES ACROSS THE NORTHERN LAKE TONIGHT.

OTHERWISE...ONCE THE THE TROUGH AND CONVECTION SLIDE THROUGH...DRY
MID LEVEL AIR WILL SURGE OVER THE AREA AND LEAD TO A FAIRLY QUIET
NIGHT WITH DECREASING CLOUDS FROM WEST TO EAST. WITH THE MOIST
SOUTHERLY FLOW OFF LAKE MICHIGAN AND THE POTENTIAL FOR SOME FOG OFF
THE LAKE WITH THE SHOWERS UPSTREAM...HAVE ADDED IN FOG OVER EASTERN
UPPER MICHIGAN. ALSO ADDED A MENTION OVER CENTRAL/EASTERN LAKE
SUPERIOR...ALONG WITH THE KEWEENAW...SINCE THERE IS A DENCENT
CONSISTENCY IN THE MODELS AND THERE ARE 50S AND LOW 60S DEWPOINTS
MOVING OVER WESTERN/CENTRAL LAKE SUPERIOR THIS AFTERNOON.
UNFORTUNATELY...CLOUDS HAVE OBSCURED THE LAKE TO SEE IF ANY FOG IS
GOING...BUT SHIP OBS HAVE YET TO REPORT FOG.

EXPECT SUNDAY TO START OFF ON THE NICE SIDE WITH A DECENT AMOUNT OF
SUNSHINE...AS THE AREA IS STILL UNDER THE 900-500MB DRY AIR. THIS
DRY AIR WILL SLIDE EAST-SOUTHEAST THROUGH THE DAY AS THE UPPER
LOW WEST OF LAKE WINNIPEG SHEARS OFF AND STARTS TO SEND PIECES OF
ENERGY ACROSS THE AREA. THE ABUNDANT SUNSHINE TO START THE DAY WILL
ALLOW TEMPERATURES TO QUICKLY RISE INTO THE 70S...WITH A FEW
VALUES IN THE LOWER 80S OVER THE SOUTH CENTRAL.

AS FOR FORCING FEATURES...SURFACE LOW ASSOCIATED WITH THE ELONGATED
TROUGH WILL BE RE-FOCUSING EAST OF LAKE SUPERIOR SUNDAY MORNING AND
THEN PUSHING EAST INTO SOUTHEASTERN ONTARIO ON SUNDAY AFTERNOON...AS
THE MAIN AREA OF SHORTWAVE ENERGY FOLLOWS THAT SAME TRACK. THIS WILL
LEAVE A SURFACE TROUGH OR COLD FRONT BACK ACROSS LAKE
SUPERIOR...WHICH WILL START TO DROP SOUTH OVER UPPER MICHIGAN DURING
THE AFTERNOON HOURS. AS THAT OCCURS...THE INCREASING 850-750MB
MOISTURE SHOULD SPARK SOME HIGH BASED DIURNAL CU. WITH MODEL
CONSENSUS ML CAPE VALUES AROUND 400J/KG...QUESTION COMES TO IF THERE
WILL BE ENOUGH MOISTURE FOR SHOWERS TO DEVELOP. MARGINAL MID-LEVEL
MOISTURE AND DECENT DRY AIR ABOVE 650MB WILL LIKELY
LIMIT THINGS...BUT DID INCLUDE SLIGHTS AND LOW END CHANCES FROM MID
AFTERNOON ON IN CASE THE DEEPER MOISTURE WITH THE TROUGH ARRIVES A
LITTLE QUICKER. IF THERE WASN/T THE INVERTED V LOOK TO THE
SOUNDINGS WITH THE MIXING TO 800-700MB WOULD HAVE CONSIDERED THE
HIGHER INSTABILITY VALUES SEEN IN THE NAM...ML CAPE VALUES AROUND
1000 J/KG...AND BOOSTED POPS UP MORE. EXPECT THE SEVERE THREAT TO BE
LIMITED WITH THESE SHOWERS/THUNDERSTORMS UNLESS THE NAM SOLUTION
VERIFIES. THIS IS DUE TO THE CAPE IS FAIRLY TALL/SKINNY WITH NCAPE
VALUES BELOW 0.1 ALTHOUGH EFFECTIVE SHEAR VALUES ARE IN THE 30-40KT
RANGE. GUSTY WINDS COULD BE A CONCERN WITH THAT INVERTED V
LOOK...DCAPE VALUES OVER 750 J/KG OVER THE SOUTH CENTRAL...AND
EXISTING WINDS GUSTING TO 20-25KTS OVER THE WESTERN CWA.

.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 432 PM EDT SAT JUN 15 2013

THE FIRST HALF OF THE UPCOMING WEEK WILL FEATURE NW FLOW INTO THE
UPPER GREAT LAKES BTWN A RIDGE DRIFTING FROM THE ROCKIES TO THE
PLAINS AND A BROAD TROF OVER ERN NAMERICA. LATER IN THE WEEK...RIDGE
PROGRESSING INTO THE PLAINS WILL BE SUPPRESSED BY SHORTWAVE ENERGY
EJECTING E FROM A TROF OVER THE PACIFIC NW. WHILE THERE MAY BE SOME
LIMITED OPPORTUNITIES FOR PCPN...NW FLOW WILL NOT SUPPORT
WIDESPREAD/SIGNIFICANT RAINFALL THRU MID WEEK. THE LATE WEEK PERIOD
COULD THEN BECOME ACTIVE WITH BETTER PCPN PROSPECTS AS SHORTWAVES
EJECT E ACROSS THE NRN PLAINS TO THE GREAT LAKES. AS FOR TEMPS...
COOLEST WEATHER WILL OCCUR EARLY IN THE WEEK BEHIND SHORTWAVE
PASSING SUN NIGHT/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 WILL BE ABOVE NORMAL WITH WARMER/MORE HUMID
CONDITIONS.

BEGINNING SUN NIGHT/MON...CURRENTLY WELL-DEFINED MID-LEVEL LOW OVER
SASKATCHEWAN WILL BE WEAKENING CONSIDERABLY/OPENING UP AS IT GETS
SHEARED ESE IN THE FLOW BTWN RIDGE OVER THE ROCKIES AND AMPLIFYING
ERN CANADA TROF. DESPITE THE CURRENT VIGOROUS APPEARANCE/RELATIVELY
LARGE CIRCULATION OF MID-LEVEL LOW...RECENT MODEL TRENDS POINT
TOWARD A WEAKER REMNANT DROPPING THRU THE UPPER MISSISSIPPI
VALLEY/WRN GREAT LAKES WITH BULK OF DEEP LAYER FORCING PER QVECTORS
PASSING BY TO THE SW AND S OF UPPER MI SUN NIGHT/MON. AS SUCH...WILL
ONLY CONTINUE CHC POPS FOR SHRA/TSRA SUN NIGHT INTO MON MORNING.
WITH SHORTWAVE SWINGING BY TO THE S OF UPPER MI MON AND WITH
VIGOROUS LOW/MID LEVEL DRYING SURGING INTO THE AREA FROM THE N IN
THE WAKE OF SHORTWAVE ROTATING THRU NRN ONTARIO...EXPECT ANY SHRA TO
END FROM NW TO SE DURING THE DAY WITH CLEARING FOLLOWING. IT WILL BE
A COOLER DAY...ESPECIALLY NEAR LAKE SUPERIOR...DUE TO BREEZY N WINDS
AND CLOUDS DOMINATING INTO AT LEAST EARLY AFTN. A CHILLY NIGHT IS
THEN ON THE WAY FOR MON NIGHT 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 OUR RECENT TREND
OF LOWERING MIN TEMPS FOR MON NIGHT. WILL FAVOR LOWER END OF MODEL
GUIDANCE...ESPECIALLY OVER THE W WHERE SFC HIGH PRES CENTER WILL BE
ARRIVING DURING THE NIGHT. WITH IDEAL RADIATIONAL COOLING
CONDITIONS...FROST IS CERTAINLY POSSIBLE IN THE USUAL COLDER
AREAS...AND A MENTION OF FROST WILL BE INCLUDED IN FCST. 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 POSSIBLY BROKEN.

IN THE WAKE OF THE SHORTWAVE PASSAGE MON...SFC HIGH PRES WILL SETTLE
INTO 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.
UTILIZING MIXING HEIGHTS TO DETERMINE POSSIBLE DWPT CRASH IN THE
AFTN SUGGESTS DWPTS COULD DROP INTO THE 20S IN THE INTERIOR...BUT
DID NOT GO THAT LOW JUST YET. EVEN WITH MID 30S DWPTS...RH WILL
BOTTOM OUT AROUND 25PCT. FORTUNATELY...LIGHT WINDS WILL KEEP FIRE WX
CONCERNS IN CHECK. MEDIUM RANGE GUIDANCE HAS AND CONTINUES TO HINT
THAT A SHORTWAVE MAY DROP SE...PASSING JUST N OF UPPER MI WED/WED
NIGHT. GIVEN THE FAIRLY CONSISTENT SIGNAL FROM ALL MEDIUM RANGE
GUIDANCE...IT APPEARS THERE MAY BE SOME PCPN AT SOME POINT LATER
WED/WED NIGHT. NOTHING MORE THAN SCHC POPS ARE WARRANTED AT THIS
TIME GIVEN THE UNCERTAINTY AND WHAT SHOULD BE LOW COVERAGE 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.

IT WOULD APPEAR THU SHOULD BE DRY. HOWEVER...THERE IS THE POTENTIAL
FOR SUBTLE BOUNDARY ASSOCIATED WITH 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. SCHC/LOW CHC POPS WERE INCLUDED IN FCST.

AS MENTIONED EARLIER...THE LATE WEEK PERIOD COULD BECOME ACTIVE AS
SHORTWAVES TRACK ACROSS THE NRN CONUS TO THE GREAT LAKES...
SUPPRESSING THE RIDGE THAT WAS SHIFTING ACROSS THE PLAINS TO THE
MISSISSIPPI VALLEY. SIGNAL LOOKS STRONG ENOUGH TO WARRANT AT LEAST
MID RANGE CHC POPS FOR SHRA/TSRA FOR MUCH OF FRI AND SAT.
&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 133 AM EDT SUN JUN 16 2013

FOG AND LOW CLOUDS WILL MAKE THE FCST A CHALLENGE THIS MORNING. TEMPO
IFR VIS WILL OCCUR OVERNIGHT AT IWD AND SAW WITH FOG AND THEN VFR
CONDITIONS ARE EXPECTED THROUGH THE REST OF THE PERIOD WITH MIXING
TAKING PLACE DURING THE DAY. AT CMX EXPECT LIFR TO VLIFR VSBY IN FOG
AS IT ADVECTS IN OFF THE LAKE. THIS SHOULD MIX OUT BY MORNING WITH
VFR CONDITIONS EXPECTED THEN THROUGH REST OF PERIOD AT CMX. &&

.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 432 PM EDT SAT JUN 15 2013

EXPECT WINDS LESS THAN 20KT ACROSS LAKE SUPERIOR THRU THE FCST
PERIOD AS PRES GRADIENT WILL REMAIN GENERALLY WEAK...TYPICAL OF THE
WARM SEASON. THERE MAY BE SOME FOG PATCHES THRU SUN EVENING BEFORE
DRIER AIR BEGINS TO SURGE S INTO THE AREA. IF SOME RAINFALL OCCURS
OVER THE LAKE...FOG WILL BE MORE LIKELY TO FORM AND BECOME MORE
WIDESPREAD/DENSE.
&&

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

$$

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