FXUS63 KMQT 120510
AFDMQT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MARQUETTE MI
1210 AM EST FRI MAR 12 2010

.SHORT TERM /TONIGHT AND FRIDAY/...ISSUED AT 422 PM

RAIN BAND EXTENDING FROM MINNEAPOLIS BACK INTO SOUTH CENTRAL LOWER
MICHIGAN IS STEADILY PUSHING NORTH. EVEN HAD A FEW ISOLATED
LIGHTNING STRIKES ALONG THE WISCONSIN BORDER DESPITE NO SIGNIFICANT
INSTABILITY. LIGHTNING THREAT APPEARS TO BE OVER ESPECIALLY GIVEN
DAYTIME HEATING LOSS. LATEST RADAR TRENDS SHOW RAIN WILL MOVE INTO
FAR SOUTHERN MENOMINEE COUNTY JUST AFTER SUNSET...THEN TO THE
REMAINDER OF THE BORDER COUNTIES JUST AFTER 00Z. BASED ON MODEL
TRENDS DECIDED TO SPEED UP OVERALL PROGRESSION OF RAIN...WITH
HEAVIER RAIN ENDING LATE TOMORROW MORNING FROM SOUTH TO NORTH. LEFT
ONLY A CHANCE FOR RAIN IN THE AFTERNOON AS BROAD ASCENT PER DIV Q
FIELDS EXITS TO THE NORTHWEST BY 18Z. AIRMASS IN PLACE OVER UPPER
MICHIGAN TONIGHT IS VERY MOIST WITH PWAT/S AROUND 200-250% OF
NORMAL. WITH THIS ABUNDANT MOISTURE EXPECT WIDESPREAD PRECIPITATION
OVERNIGHT...THOUGH NOT ANTICIPATING RAINFALL TO BE HEAVY GIVEN LACK
OF STRONG LIFT. MAIN FORCING IS AN EMBEDDED DISTURBANCE ROTATING
AROUND THE PARENT LOW IN IOWA...ALONG WITH MARGINAL 500MB HEIGHT
FALLS SLOWLY OVERSPREADING THE FA. GIVEN THIS LIFT...FOR TONIGHT
INTO FRIDAY MORNING EXPECT AROUND A QUARTER INCH OF RAINFALL WEST
AND CENTRAL TO AROUND AN TENTH IN THE EAST. SOUTH CENTRAL AREAS MAY
SEE A BIT MORE RAINFALL WHERE CONVECTIVE RAINFALL LATE THIS
AFTERNOON COULD BOOST TOTALS A BIT. AS THIS LOW MOVES FROM IOWA THIS
EVENING TO SOUTHERN ILLINOIS BY TOMORROW EVENING EXPECT
PRECIPITATION TO TAPER OFF TOMORROW AFTERNOON. EXPECT FOG TO BE A
PROBLEM AGAIN TONIGHT INTO FRIDAY AS LOW LEVEL MOISTURE REMAINS.

.LONG TERM (FRIDAY NIGHT THROUGH NEXT THURSDAY)...

NO MAJOR STORM SYSTEMS FOR THE EXTENDED PERIOD. SOME HINTS FROM
MEDIUM RANGE GUIDANCE THAT MORE SIGNIFICANT SYSTEM COULD AFFECT
CNTRL PORTION OF THE CONUS BY THE NEXT WEEKEND AND PERHAPS IN
ITS WAKE TEMPS COULD TREND BACK BLO NORMAL TOWARD THE END
OF THE MONTH. PLENTY OF TIME TO SORT THAT OUT. FOR THE DAYS 4-7
FCST...INITIAL FOCUS IS ON HOW QUICK UPPER LOW THAT IS CURRENTLY
NEARBY WILL HEAD OFF INTO THE ATLANTIC. SLOWER SOLUTION SEEMS
REASONABLE CONSIDERING EXTENT OF BLOCKING DOWNSTREAM FM EASTERN
CANADA INTO GREENLAND.

GENERALLY...FLAVOR OF ONGOING FCST FOR FRIDAY NIGHT THROUGH
SATURDAY NIGHT WAS KEPT IN TACT. BEST CHANCE OF RAIN FIRST PART OF
THIS PERIOD IMPACTS SCNTRL AND SW UPR MI AS THAT AREA IS ON FRINGE
OF LIFT FM SHORTWAVE ROTATING AROUND UPR LOW TO THE SOUTH. INITIALLY
THOUGHT OF GOING WITH LIKELY POPS FOR THE SCNTRL BUT KEPT AT HIGH
CHANCE SINCE NAM/GFS MOS POPS AT MNM ARE CHANCY AT BEST AND MAJORITY
OF GUIDANCE OVR MULTIPLE MODEL RUNS IS PERSISTENT INDICATING SRN CWA
STAYS ON FRINGE OF WEAK LIFT/Q-VECTOR CONVERGENCE AND PROGGED QPF.
INCREASED COVERAGE OF FOG FRIDAY NIGHT INTO SATURDAY WITH MAINLY LGT
ERLY WINDS AND LWR 40S DWPNTS OVR MUCH OF WI TRYING TO ADVECT INTO
UPR MI. ADDITIONAL LOW-LEVEL MOISTURE COMES FM RAINFALL TONIGHT INTO
FRIDAY. PROVIDING WINDS ON NORTH EDGE OF THE SFC LOW DO NOT BECOME
TOO STRONG/MIXING BECOMES MORE OF AN ISSUE...SETUP SEEMS VERY GOOD
FOR WIDESPREAD DENSE FOG AND MAYBE EVEN A DENSE FOG ADVY FRIDAY
NIGHT INTO SATURDAY AM.

MOST RAIN WITH THE UPPER LOW SHOULD BE DONE BY SATURDAY NIGHT. MAIN
IMPACT WITH SLOWER SOLN INTO EARLY THIS WEEK IS A PERSISTENT/WEAK
NRLY WIND IN THE LOW-LEVELS BTWN HIGH PRESSURE RIDGE OVR MN AND LOW
PRESSURE OVR THE WESTERN ATLANTIC OCEAN. PRESSURE PATTERN RESULTS IN
TEMPS ALONG LK SUPERIOR REMAINING IN THE LOWER 40S WHILE READINGS
INLAND TOP OUT IN THE 50S. COULD ALSO BE SOME LINGERING CLOUDS
AROUND IN THE WEAK CYCLONIC FLOW. WEAK FRONT PUSHES THROUGH ON
TUESDAY...BUT SINCE MAJORITY OF LARGE SCALE FORCING PASSES WELL TO
THE NORTH ACROSS HUDSON BAY...HAVE JUST INCREASED CLOUDS AND WENT
WITH NO POPS. BY WEDNESDAY...UPPER RIDGING AND SFC RIDGE BUILD
ACROSS UPR LAKE LEADING TO CLEARING SKIES AND TEMPS WARMING UP IN
THE NORTHERN TIER OF CWA COMPARED TO EARLIER IN THE WEEK. DRY
WEATHER CONTINUES INTO THURSDAY.

SFC HIGH SETTLING TO THE SOUTH...A FRONT SLIDING BY TO THE NORTH
ACROSS ONTARIO...AND DEVELOPING LOW PRESSURE IN THE CANADIAN
PRAIRIES YIELD INCREASING WRLY WIND WITH WARMING 925-850MB TEMPS. AS
IS THE CASE MOST OF THE DAYS 4-7 PERIOD...925MB TEMPS FM THE GFS ARE
AT LEAST 4C COOLER THAN THE ECMWF. LOCAL VERIFICATION SHOWS ECMWF
HAS BEEN PERFORMING VERY WELL FOR TEMPS IN CURRENT WARM PATTERN...
AND THE 12Z GFS SEEMS TO BE TRENDING WARMER...SO TILTED TOWARD THE
ECMWF. A BIT EARLY...BUT TEMPS NEXT THURSDAY COULD BE INTO THE 60S
FOR MANY AREAS. LOW TEMPERATURES THROUGH THE PERIOD REMAIN ABOVE
CLIMATOLOGY (NORMAL LOW TEMPS AT KMQT IN THE LOW-MID TEENS)...BUT
WILL STILL LIKELY FALL BLO FREEZING IN THE INTERIOR TUE-THU AS THE
HIGH PRESSURE IS IN CLOSE PROXIMITY.
&&

.AVIATION /FOR THE 06Z TAFS/...

VFR CONDITIONS ARE EXPECTED TO DETERIORATE TO IFR OVERNIGHT AS AN
AREA OF RAIN MOVES THROUGH UPPER MICHIGAN OVERNIGHT INTO EARLY FRI
MORNING. SOME IMPROVEMENT IS EXPECTED BY MIDDAY WITH DAYTIME MIXING.
HOWEVER...MOIST ERLY FLOW SHOULD STILL FAVOR IFR OR LOWER END MVFR
CIGS UNTIL AFTERNOON WITH UPSLOPE FLOW INTO BOTH TAF SITES. ANY
BREAKS IN THE LOWER CLOUDS ARE EXPECTED TO FILL BACK IN FRI EVENING.
&&

.MARINE /FOR THE 4 PM LAKE SUPERIOR FORECAST/...

LOW PRESSURE CENTERED NEAR THE MID MISSISSIPPI VALLEY WILL ALLOW FOR
EAST TO NORTHEAST WIND OVER THE LAKE THROUGH THE WEEKEND. TONIGHT
AND INTO FRIDAY MORNING WINDS MAY EXCEED 25 KNOTS...OTHERWISE EXPECT
WINDS BELOW 20 KNOTS. HIGH PRESSURE WILL SLOWLY MOVE OVER THE LAKE
DURING NEXT WEEK ALLOWING WINDS TO BE LIGHT BUT REMAIN NORTHERLY.
&&

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

$$

SHORT TERM...PEARSON
LONG TERM...JLA
AVIATION...PEARSON
MARINE...PEARSON





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