000
FXUS63 KMQT 071758 AAB
AFDMQT
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE MARQUETTE MI
100 PM EST SAT NOV 7 2009
UPDATED AVIATION DISCUSSION FOR 18Z TAFS
SYNOPSIS /ISSUED AT 415 AM EST/
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A LOW AMPLITUDE FLOW
ACROSS THE CONUS AND SRN CANADA...FEATURING A RIDGE OVER SE CANADA
AND BROAD TROFFING FROM THE GULF OF ALASKA INTO WRN NAMERICA. RESULT
IS PACIFIC AIR SPREADING ACROSS THE CONUS AND SRN CANADA. IN
RESPONSE TO A SHORTWAVE AND ASSOCIATED SFC LOW OVER MANITOBA...SRLY
WINDS NEAR THE SFC HAVE BROUGHT SFC DWPTS WELL INTO THE 40S TO
AROUND 50F INTO ERN MN AND WRN WI. DESPITE THE SURGE OF SHALLOW
LOW-LEVEL MOISTURE...STRATUS HAS FAILED TO MATERIALIZE AS EXPECTED.
ABOVE THE SHALLOW NEAR SFC MOISTURE...AIRMASS REMAINS VERY DRY PER
00Z SOUNDINGS. THUS...THERE HAS BEEN NO PCPN IN THE WAA PATTERN.
UPSTREAM...AIRMASS WAS VERY WARM YESTERDAY WITH SOME RECORD HIGHS
TIED/BKN IN THE CNTRL/WRN DAKOTAS WHERE TEMPS SOARED WELL INTO THE
70S.
DISCUSSION /ISSUED AT 415 AM EST/
OVERALL...TEMPS WILL AVERAGE ABOVE NORMAL THRU THIS FCST PERIOD AS
PACIFIC AIR DOMINATES UNDER GENERALLY LOW AMPLITUDE/PROGRESSIVE
FLOW. IN FACT...EVEN OUT TO 2 WEEKS...CPC 8-14DAY OUTLOOK INDICATES
TEMPS WILL LIKELY CONTINUE TO AVERAGE ABOVE NORMAL.
SHORTWAVE OVER MANITOBA WILL MOVE ACROSS NRN ONTARIO TODAY. WITH
VERY DRY AIRMASS DOMINATING UPSTREAM PER 00Z SOUNDINGS...PCPN IS NOT
A CONCERN. STRATUS/FOG STILL HAS A CHANCE TO DEVELOP OVER THE
NEXT FEW HRS AS HIGHER DWPTS ADVECT N INTO SHALLOW SLIGHTLY COOLER
AIRMASS OVER THE FCST AREA. EVEN IF STRATUS/FOG DOES DEVELOP...GOOD
PUSH OF DRY AIR PER 00Z KBIS SOUNDING ON WRLY WINDS BEHIND SFC TROF
PROGRESSING ACROSS THE FCST AREA THIS MORNING THRU EARLY AFTN WILL
BRING CLEARING FROM W TO E. GIVEN THE WARMTH OBSERVED UPSTREAM
YESTERDAY...INHERITED FCST APPEARS ON TRACK...BUT DID BUMP UP HIGHS
A FEW DEGREES SINCE LOW CLOUDS MAY NOT BE AN ISSUE AT ALL DURING THE
MORNING...ALLOWING TEMPS TO BEGIN RISING QUICKER. EXPECT HIGHS WELL
INTO THE 50S/LWR 60S WITH SOME MID 60S CERTAINLY POSSIBLE IN THE
SCNTRL DOWNSLOPE AREAS. NOT OUT OF THE QUESTION THAT RECORD HIGH OF
61F HERE AT THE OFFICE COULD BE REACHED...MAYBE BKN TODAY IF SKIES
END UP MOSTLY SUNNY THRU THE DAY.
QUIET NIGHT EXPECTED TONIGHT WITH SFC HIGH PRES RIDGE SHIFTING TO
THE WRN GREAT LAKES. WITH MOSTLY CLEAR SKIES/DRY AIRMASS...WILL LEAN
TO THE LOW END OF MOS GUIDANCE TONIGHT (MID/UPPER 20S IN THE
INTERIOR).
MID LEVEL FLOW BECOMES A LITTLE MORE SW SUN AS HEIGHTS GRADUALLY
RISE OVER THE ERN CONUS. IN THE MORE CONFLUENT FLOW TO THE N AND
NE...GRADUAL RISE IN HEIGHTS RESULTS IN STRENGTHENING UPPER JET FROM
NRN ONTARIO TO MAINE WHICH PLACES RIGHT ENTRANCE REGION DIVERGENCE
OVER THE UPPER LAKES SUN AFTN. IN RESPONSE...VERY WEAK SFC LOW TAKES
SHAPE IN SRN MN WITH ISENTROPIC ASCENT AND BAND OF LOW-MIDLEVEL
FRONTOGENESIS LIFTING NE INTO UPPER MI. GFS/UKMET ARE MOST
AGGRESSIVE DEVELOPING A STREAK OF PCPN INTO WRN UPPER MI/LAKE
SUPERIOR ASSOCIATED WITH FORCING. HAVE SOME DOUBT WHETHER FORCING
AND MOISTURE RETURN WILL BE SUFFICIENT TO OVERCOME ANTECEDENT
LOW-LEVEL DRY AIR THAT QUICKLY. HOWEVER...SINCE INHERITED FCST HAD
SLIGHT CHC POPS GOING FOR WRN UPPER MI...WILL LEAVE THAT IN PLACE
FOR THIS FCST ISSUANCE AS CONFIDENCE IS NOT HIGH ENOUGH TO PULL
POPS. WHILE AIRMASS IS STILL MILD WITH 850MB TEMPS IN THE 4-7C
RANGE...LIGHT/VRBL WINDS BECOMING ERLY AND INCREASING MID CLOUDS
WILL MAKE FOR A COOLER DAY THAN TODAY. STILL...HIGHS SHOULD TOP OUT
WELL ABOVE NORMAL IN THE 50S.
WEAK SFC LOW SHIFTS THRU THE UPPER GREAT LAKES SUN NIGHT. WITH
MODEST FORCING AND LACK OF STRONG MOISTURE RETURN...CHC POPS LOOK
FINE FOR NOW.
WEAK SFC WAVE/FRONTAL BOUNDARY WILL GET KICKED EWD MON AS NEXT
SHORTWAVE MOVES FROM THE DAKOTAS/SCNTRL CANADA MON INTO THE GREAT
LAKES TUE. WITH EXITING BOUNDARY...OPTED TO END PCPN QUICKER FROM W
TO E MON. ALTHOUGH FLOW WILL BEGIN TO AMPLIFY WITH SHORTWAVE DIGGING
INTO THE GREAT LAKES MON NIGHT...CAA ONLY DROPS 850MB TEMPS TO
AROUND -2C WHICH WON'T BE SUFFICIENT FOR ANY LAKE EFFECT PCPN.
SO...DRY WEATHER IS EXPECTED MON NIGHT.
IN THE WAKE OF THE DEPARTING AMPLIFYING TROF...MID/UPPER RIDGE WILL
BUILD INTO THE WRN GREAT LAKES TUE/TUE NIGHT...PROVIDING DRY
WEATHER. RIDGE WILL LOSE AMPLITUDE AND SHIFT E WED AS NEXT
SHORTWAVE TRACKS E THRU CNTRL CANADA. WITH SHORTWAVE WELL N AND NW
OF THE AREA PER ALL MEDIUM RANGE GUIDANCE...EXPECT DRY WEATHER TO
CONTINUE INTO WED.
AVIATION /FOR THE 18Z TAF ISSUANCE/
KCMX HAS GOTTEN QUITE GUSTY BEHIND THE FRONT THAT PASSED THROUGH THE
AREA THIS MORNING. THE GUSTS WIND SHOULD CONTINUE THROUGH THE
AFTERNOON HOURS. KSAW WAS LAST TO GET RID OF FOG THIS MORNING AND
HAS NOT HAD THAT MUCH MIXING AS OF YET. THE WIND SHOULD INCREASE
THROUGH THE AFTERNOON HOURS WITH DAYTIME HEATING AND THEN DIMINISH
AFTER SUNSET. WITH THE WIND BECOMING ALMOST CALM AT KSAW SHORTLY
AFTER SUNSET AND A STRONGER WIND CORE REMAINING JUST ABOVE THE
SURFACE THROUGH 6Z...MENTIONED WIND SHEAR THROUGH THAT TIME. WIND
WILL REMAIN HIGHER AT KCMX OVERNIGHT SO DID NOT MENTION WIND SHEAR.
WITH MOSTLY CLEAR SKIES EXPECTED TONIGHT...EXCELLENT RADIATIONAL
COOLING MAY LEAD TO SOME GROUND FOG DEVELOPMENT AT KSAW.
MARINE /FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE/
WINDS HAVE DIMINISHED OVER MOST OF LK SUPERIOR THIS MORNING.
EXCEPTION IS OVR FAR SE SECTIONS BTWN CARIBOU ISLAND AND WHITEFISH
POINT...WHERE A SRLY FEW GALE GUSTS MAY STILL OCCUR THROUGH SUNRISE.
DIMINISHING TREND OVR THE LAKE IS BRIEF AS PASSAGE OF LOW PRESSURE
TROUGH THIS MORNING WILL KICK UP WEST WINDS TOWARD 30 KTS LATE THIS
MORNING INTO THIS EVENING. WINDS DIMINISH LATER TONIGHT WITH ARRIVAL
OF A WEAKER PRESSURE GRADIENT. BEYOND TONIGHT...EXPECT WINDS TO STAY
BELOW 25 KTS INTO THE MIDDLE OF NEXT WEEK AS AN OVERALL WEAK PRES
GRADIENT DOMINATES.
MQT WATCHES/WARNINGS/ADVISORIES
UPPER MICHIGAN...NONE.
LAKE SUPERIOR...NONE.
LAKE MICHIGAN...NONE.
SYNOPSIS/DISCUSSION...ROLFSON
AVIATION...AJK
MARINE...JLA
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