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000
FXUS63 KMQT 061019
AFDMQT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MARQUETTE MI
519 AM EST THU MAR 6 2014

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 458 AM EST THU MAR 6 2014

MAIN FOCUS IS WITH WINDS AND PRECIP CHANCES TODAY INTO TONIGHT AS A
COUPLE OF SHORTWAVES PASS NEARBY.

CURRENTLY...THE CWA IS BETWEEN A 1040MB HIGH CENTERED OVER SRN
QUEBEC AND A DEVELOPING 1006MB LOW LEEWARD OF THE MT ROCKIES. A
COUPLE OF SHORTWAVES ARE MODELED TO MOVE THROUGH THE REGION THROUGH
TONIGHT. THE FIRST IS WELL AGREED ON BY THE MODELS AS MOVING N OF
LAKE SUPERIOR TODAY...KEEPING ALMOST ALL OF THE ASSOCIATED PRECIP N
OR THE CWA. THIS SHORTWAVE...HOWEVER...MAY HELP TO MOISTEN THE VERY
DRY MID LEVEL AIRMASS CURRENTLY IN PLACE OVER THE CWA. THE SECOND
SHORTWAVE IS ASSOCIATED WITH THE DEVELOPING NRN PLAINS LOW AND WILL
MOVE /ALONG WITH THE SFC LOW/ TO NWRN LAKE SUPERIOR BY 12Z FRI. THIS
IS THE GENERAL CONSENSUS WITH THE EXACT PLACEMENT/TIMING...AS MODELS
ARE DISAGREEING WITH THE EXACT TRACK AND SPEED. GIVEN THE DRY
AIRMASS IN PLACE...WILL UTILIZE DRIER MODELS THAT ARE SLOWER TO
BRING PRECIP IN...MAINLY THE NAM AND REGIONAL GEM. BY 12Z
FRI...BARRING THE GFS /WHICH IS FASTEST WITH THE PRECIP AND COVERS
MUCH OF THE CWA/ CONSENSUS OF OTHER MODELS HAS PRECIP GETTING INTO
NW AND NCENTRAL UPPER MI. PRECIP SHOULD BE MAINLY SNOW...BUT THERE
IS A CHANCE SOME SLEET COULD OCCUR GIVEN A SHALLOW WARM LAYER ALOFT
THAT WOULD BE JUST ABOVE 0C. DECREASED MIXED PRECIP WORDING AND WENT
WITH PRIMARILY SNOW GIVEN THE MINIMAL MAGNITUDE TO THE WARM LAYER.

IT WILL BE WINDY TODAY INTO TONIGHT AS 925MB WINDS WILL BE GREATER
THAN 40KTS THROUGH MUCH OF THE SHORT TERM. THE MAXIMUM GUST
POTENTIAL IS AROUND 40KTS...BUT MOST LIKELY GUSTS OVER LAND WILL BE
IN THE 20-35KT RANGE...WHICH MAY REQUIRE AN INCREASE TO FORECAST
WIND GUSTS WHICH ARE ONLY AT 25-30KTS.

.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 518 AM EST THU MAR 6 2014

OVER THE NEXT 7 DAYS...VERY COLD AIR WILL CONTINUE TO LINGER ACROSS
MUCH OF CANADA...ESPECIALLY IN THE VCNTY OF HUDSON BAY. HOWEVER...
SINCE THE FLOW REGIME ACROSS THE CONUS WILL BE LOWER AMPLITUDE...
THIS VERY COLD AIR WILL STAY TO THE N OF UPPER MI THRU THIS FCST
PERIOD. THERE CONTINUES TO BE A TENDENCY FOR VARYING DEGREES OF
RIDGING OVER WRN NAMERICA WHICH RESULTS IN A MEAN TROF FROM THE
UPPER MISSISSIPPI VALLEY TO NEW ENGLAND. DURING THE EARLY PORTION OF
NEXT WEEK...THIS WILL SET THE STAGE FOR A TIGHT THERMAL GRADIENT
ROUGHLY ACROSS THE UPPER MISSISSIPPI VALLEY/UPPER GREAT LAKES
REGION. SHORTWAVES MOVING ALONG IN THIS WNW FLOW PATTERN WILL THEN
PROVIDE THE PROSPECT FOR PERIODIC PCPN ACROSS THE UPPER LAKES. WHILE
NO SIGNIFICANT PCPN APPEARS TO BE IN THE OFFING...SHORTWAVES
TRACKING ALONG THE TIGHT THERMAL GRADIENT SUCH AS WILL BE OVER/NEAR
THE AREA CAN SOMETIMES PRODUCE VERY NARROW BANDS OF MDT OR EVEN HVY
PCPN. WILL BE SOMETHING TO WATCH. OTHERWISE...THE RETREAT OF ARCTIC
AIR WILL RESULT IN TEMPS RETURNING CLOSER TO NORMAL THRU THE FIRST
HALF OF NEXT WEEK...AND THERE MAY BE A DAY OR TWO OF ABOVE NORMAL
TEMPS. HOWEVER...TEMPS COULD VARY RATHER DRAMATICALLY FROM FCST IF
THERMAL GRADIENT EARLY NEXT WEEK IS SHIFTED ONLY SLIGHTLY FARTHER N
OR S. DURING THE LAST HALF OF NEXT WEEK...IT LOOKS LIKE THE ERN TROF
WILL AMPLIFY...BRINGING TEMPS MORE SOLIDLY BLO NORMAL AGAIN...BUT
NOWHERE NEAR WHAT HAS BEEN EXPERIENCED IN THE LAST WEEK AND A HALF.

BEGINNING FRI...SHORTWAVE OVER SRN MANITOBA/NRN ONTARIO EARLY IN THE
MORNING WILL SHIFT E...CROSSING THE UPPER LAKES FRI EVENING.
STRONGEST DEEP LAYER FORCING PER QVECTORS WILL PASS N OF UPPER MI
DURING THE MORING AND EARLY AFTN. MEANWHILE...ISENTROPIC ASCENT WILL
ALREADY BE SHIFTING OUT OF WRN UPPER MI AT 12Z AND WILL EXIT THE E
BY AFTN. AS A RESULT...THERE SHOULD BE 2 MAIN AREAS OF PCPN FRI...
ONE MOSTLY OVER THE ERN FCST AREA IN THE MORNING WITH ISENTROPIC
ASCENT AND THE OTHER MAINLY N OF UPPER MI DURING THE MORNING TIED
MORE CLOSELY TO SHORTWAVE DYNAMICS PASSING N OF THE AREA. FCST
SOUNDINGS SHOW SOME POSSIBILITY OF MIXED PTYPES...MAINLY ACROSS THE
S. FORTUNATELY...PCPN WILL BE LIGHT WHERE IT OCCURS. AT THE
SFC...COLD FRONT ARRIVING OVER WRN LAKE SUPERIOR EARLY IN THE
MORNING WILL SHIFT E...EXITING THE ERN FCST AREA LATE IN THE
AFTN/EARLY EVENING. WILL CONTINUE WITH PCPN CHANCES UNTIL FROPA.
AFTER FROPA...WOULD NORMALLY HAVE TO DEAL WITH LES/LAKE ENHANCED
SNOW IN CYCLONIC CAA REGIME...BUT SINCE LAKE SUPERIOR IS MOSTLY ICE
COVERED...POTENTIAL IS MINIMIZED. HOWEVER...WITH THE STRONG WINDS
TODAY/TONIGHT AND AFTER FROPA...EXPECT SOME LARGER BREAKS IN THE ICE
COVER TO OPEN UP. AS WE`VE SEEN MANY TIMES THIS WINTER...IT TAKES
VERY LITTLE OPEN WATER OR BKN ICE COVER TO GET THE LAKE EFFECT
GOING. SO...AFTER FROPA...WILL CARRY LOW POPS FOR -SHSN FRI AFTN AND
THEN FLURRIES FRI NIGHT FOR AREAS FAVORED BY N TO NW WINDS AS 850MB
TEMPS FALL TO AROUND A MARGINALLY COLD ENOUGH -14C. AS FOR TEMPS...
BEFORE THE COLD FRONT ARRIVES FRI...EXPECT TEMPS TO RECOVER TO ABOVE
FREEZING OVER A GOOD PORTION OF UPPER MI. TEMPS FRI NIGHT WILL FALL
BACK TO THE SINGLE DIGITS AND LWR TEENS. A FEW SPOTS IN THE INTERIOR
COULD SLIP BLO 0F IF SKIES CLEAR OUT AND WINDS DECOUPLE COMPLETELY.

A FEW FLURRIES/CLOUDS MAY LINGER OFF LAKE SUPERIOR SAT MORNING...BUT
OTHERWISE...EXPECT A DRY DAY AS HIGH PRES OVER THE NRN PLAINS EARLY
IN THE MORNING BUILDS INTO THE UPPER MISSISSIPPI VALLEY AND WRN
GREAT LAKES REGION DURING THE DAY. WITH DAYTIME HEATING AND A LITTLE
MOISTURE OFF THE LAKE...EXPECT SOME STRATOCU TO DEVELOP FOR A TIME
WHERE SKIES ARE MOSTLY CLEAR TO START THE DAY. WHERE WINDS ARE OFF
THE ICE COVERED LAKE...TEMPS WILL STRUGGLE TO GET OUT OF THE TEENS
SAT. SHOULD REACH THE LOW AND MID 20S INLAND. GEM/GFS HAVE WEAKENED
THE SHORTWAVE TRACKING SE INTO THE UPPER LAKES LATE SAT
AFTN/EVENING...MORE INLINE WITH WHAT THE ECMWF/UKMET HAD BEEN
SHOWING. SO...IT WON`T BE A CONCERN FOR PCPN HEADING INTO SAT
EVENING.

SAT NIGHT/SUN...GFS/ECMWF ARE IN GOOD AGREEMENT SHOWING A
SHORTWAVE/SFC LOW TRACKING ESE THRU NRN ONTARIO/UPPER LAKES. WITH
SHORTWAVE/SFC LOW FCST TO PASS N OF UPPER MI...MAIN AREA OF PCPN
WILL ALSO PASS BY TO THE N OF HERE. GFS HAS BEEN AND CONTINUES TO BE
A LITTLE MORE AGGRESSIVE WITH THE SRN EXTENT OF PCPN...AFFECTING
MOST OF UPPER MI. THAT APPEARS TO BE TIED TO OVER GENERATION OF
PCPN OUT OF A VERY SHALLOW MOIST LAYER PER ITS FCST SOUNDINGS.
MEANWHILE...THE ECMWF HAS BEEN EXTREMELY CONSISTENT IN ONLY BRUSHING
MAYBE THE KEWEENAW AND FAR NE UPPER MI WITH PCPN. WILL FAVOR ITS
SOLUTION...AND KEEP MOST OF THE FCST AREA DRY AS SHORTWAVE/SFC LOW
PASS BY TO THE N. BEING ON THE WARM SIDE OF THE DISTURBANCE...SFC
TEMPS WILL LIKELY RISE AOA 32F...PERHAPS EVEN INTO THE LOW/MID 40S
SW/SCNTRL.

ANOTHER SHORTWAVE/SFC LOW TRACKS ESE ACROSS THE UPPER LAKES/NRN
ONTARIO MON. LOOKS LIKE THIS DISTURBANCE MAY TRACK A LITTLE FARTHER
S THAN ITS PREDECESSOR...RESULTING IN A BETTER CHC OF PCPN. STILL...
THERE IS ENOUGH UNCERTAINTY GIVEN THE LAST FEW DAYS OF MEDIUM RANGE
MODEL RUNS TO KEEP POPS LOW. MUCH WARMER AIR WILL BE CARRIED ALONG S
OF THE SFC LOW TRACK. BIAS CORRECTED ECMWF/GEM TEMPS ARE QUITE WARM
ACROSS PORTIONS OF UPPER MI (UP TO 50F ECMWF AND IN THE 50S GEM).
SO...BIG TEMP BUST POTENTIAL IS THERE ON MON DEPENDING ON TRACK OF
SFC LOW. FCST FOR NOW TAKES A CONSERVATIVE APPROACH WITH HIGHS LWR
30S E TO LWR 40S TOWARD WI BORDER.

TUE/WED...SEVERAL PIECES OF ENERGY MOVING OUT OF THE ROCKIES AND SE
FROM CANADA WILL LEAD TO THE AFOREMENTIONED LATER WEEK TROF
AMPLIFICATION OVER THE E. THERE IS SIGNIFICANT SPREAD REGARDING HOW
THESE WAVES MAY INTERACT. THE GEM/UKMET DEVELOP A MORE CONSOLIDATED
SFC LOW OVER THE PLAINS THAT MOVES E ACROSS THE SRN GREAT LAKES...
POSSIBLY CLOSE ENOUGH TO BRING A DECENT SNOW TO SRN UPPER MI. THE
GFS/ECMWF ARE MORE SUPPRESSED AND WEAKER. WILL BE A TIME PERIOD TO
MONITOR. IN ANY EVENT...TREND WILL BE TOWARD COLDER WEATHER MID TO
LATE WEEK AS TROF BEGINS TO AMPLIFY.
&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1232 AM EST THU MAR 6 2014

EXPECT VFR CONDITIONS AT ALL TAF SITES THROUGH THIS FCST PERIOD.
LLWS WILL CONTINUE OVERNIGHT AT ALL SITES AS WARMER AIR BEGINS
ADVECTING OVER THE COOLER SURFACE LAYER. SURFACE TEMPS WILL WARM ON
THURSDAY ALLOWING ENOUGH MIXING TO TRANSITION LLWS TO GUSTY WINDS
THROUGH THE ENTIRE LAYER. LLWS WILL RETURN AT IWD THU EVENING AGAIN.
&&

.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 458 AM EST THU MAR 6 2014

SOUTHERLY WINDS WILL INCREASE THURSDAY AS HIGH PRESSURE SHIFTS EAST
AND LOW PRESSURE APPROACHES FROM THE WEST. WINDS WILL INCREASE TO
20-30KT OVER EASTERN LAKE SUPERIOR LATE TODAY THROUGH TONIGHT. THE
TROUGH WILL CROSS THE UPPER GREAT LAKES FRIDAY...BRINGING A WIND
SHIFT TO THE NORTHWEST. WHILE THERE MAY BE A PERIOD OF 15-25KT WINDS
BEHIND THE TROUGH...WINDS WILL DIMINISH INTO THE WEEKEND AS HIGH
PRESSURE MOVES OVER THE REGION. WINDS WILL REMAIN AT 20 KNOTS OR
LESS MONDAY AND TUESDAY.
&&

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

$$

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