http://www.crh.noaa.gov/product.php?site=mqt&product=AFD&issuedby=MQT&format=ci&version=1 Sun, 22 Nov 2009 17:00:02 GMT Marquette Area Forecast Discussion en-us w-mqt.webmaster@noaa.gov w-mqt.webmaster@noaa.gov http://www.weather.gov/images/xml_logo.gif http://www.crh.noaa.gov/mqt http://www.crh.noaa.gov/product.php?site=mqt&product=AFD&issuedby=MQT&format=ci&version=1 350 PM EST SUN NOV 22 2009

.SYNOPSIS...

WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW AN UPPER RIDGE AXIS
OVER WESTERN QUEBEC AND A LONGWAVE TROUGH OVER THE NORTHERN AND
CENTRAL PLAINS AND INTO CENTRAL CANADA. ANOTHER TROUGH CONTINUES TO
DIG OVER THE PACIFIC NORTHWEST. A WEAK SHORTWAVE IS OVER THE EAST
END OF THE FORECAST AREA THIS AFTERNOON...WITH OTHERS OVER EASTERN
DAKOTAS AND MINNESOTA. SURFACE ANALYSIS SUGGEST A COLD FRONT
EXTENDING FROM CENTRAL HUDSON BAY SOUTH THROUGH MINNESOTA TO A WEAK
LOW OVER EASTERN NEBRASKA AND A LARGE HIGH OVER THE CANADIAN
MARITIME CAUSING A SOUTHERLY FLOW ACROSS THE FORECAST AREA. THIS
SOUTHERLY FLOW BROUGHT ABNORMALLY WARM AIR AND SOME LOW LEVEL
MOISTURE INTO THE AREA WHICH CAUSED CONSIDERABLE FOG THIS MORNING.
THIS MORNING AREA RAOBS INDICATED THE AIR MASS WAS QUITE DRY ABOVE
800MB. QUITE A BIT OF HIGH CLOUDS ARE STREAMING INTO THIS AREA AHEAD
OF OF THE FRONT. A LOW LEVEL JET OVER THE AIR CONTINUES TO MIX TO
SURFACE OVER THE LAKE.

&&

.SHORT TERM...

THE MAIN CONCERN FOR TONIGHT AND MONDAY WILL BE WITH THE POTENTIAL
FOR RAIN AND FOG.

THE MID LEVEL RIDGE WILL PUSH INTO EASTERN QUEBEC WITH THE
ASSOCIATED HIGH WEAKENING AS IT REACHES NEW ENGLAND TONIGHT. THE MID
LEVEL TROUGH OVER THE NORTHERN PLAINS WILL WEAKEN AND SETTLE OVER
HUDSON BAY TONIGHT. THE ASSOCIATED SHORTWAVE WILL WEAKEN AS WELL AS
IT STALLS OUT OVER THE UPPER MISSISSIPPI RIVER VALLEY.
MEANWHILE...THE TROUGH OVER THE PACIFIC NORTHWEST CONTINUE TO DEEPEN
AS IT MOVES INTO THE NORTHERN HIGH PLAINS. THE COLD FRONT OVER
MINNESOTA WILL REALIGN WITH THE WEAKEN SHORTWAVE OVER CANADA AND
STRETCH FROM SOUTHERN JAMES BAY SOUTHWEST THROUGH THE MINNESOTA
ARROWHEAD TO EASTERN SOUTH DAKOTA. SURFACE DEW POINT ARE IN THE LOW
TO MID 40S ACROSS THE CWA THIS AFTERNOON. AFTER SUNDOWN WITH THE
CLEARING SKIES OVER THE EAST...TEMPERATURES WILL FALL RAPIDLY WILL
BE FAVORABLE FOR FOG DEVELOPMENT OVERNIGHT. INCREASE HUMIDITY AHEAD
OF THE COLD FRONT WILL INCREASE THE POSSIBILITY OF RAIN AND FOG
THERE AS WELL. THUS WILL TENDED TO GO WITH THE A LITTLE POPS LATER
TONIGHT WITH INFLUX OF MOISTURE AND SOME ISENTROPIC ASCENT AHEAD OF
THE FRONT.

THE MID LEVEL TROUGH OVER THE HIGH PLAINS WILL DEEPEN INTO A CUTOFF
LOW OVER THE CENTRAL PLAINS ON MONDAY. WEAK SHORTWAVES EJECTED OUT
OF THE BASE OF THIS LOW WILL SWEEP ACROSS THE FORECAST AREA ON
MONDAY. THE FINAL REMNANT OF THE WEAKENING TROUGH WILL SHIFT INTO
WISCONSIN. THE NEBRASKA SURFACE LOW WILL DEEPEN AS IT INCHES INTO
EASTERN NEBRASKA. A STRONG SOUTHERLY FLOW AND THE ALIGNMENT OF THE
LOW LEVEL JET WILL HOLD THE FRONTAL SYSTEM STATIONARY JUST TO THE
NORTH OF LAKE SUPERIOR. AS WITH THIS MORNING...PATCHY FOG SHOULD
LAST THROUGH THE EARLY MORNING HOURS AFTER SUNRISE. DRY AIR
ADVECTING INTO THE AREA AHEAD OF THE NEBRASKA LOW WILL END THE FOG
AND LIMIT ANY PRECIPITATION ACROSS THE AREA ON MONDAY.

&&

LONGER TERM 00Z TUE ONWARD...

FORECAST PROBLEM CONTINUES TO BE THE UPCOMING STORM AND WHAT IT WILL
DO...PCPN TYPE AND WHEN IT WILL OCCUR. THE STORM SYSTEM IS CURRENTLY
IN THE PACIFIC NW NOW AND WILL DIG SE AND FORM A CLOSED LOW WITH IT
THIS FORECAST PERIOD. NAM BRINGS IN ANOTHER TROUGH INTO THE PACIFIC
NW MON NIGHT AND THEN MOVES IT EAST BEFORE DIGGING IT INTO THE
TROUGH ON TUE. WHAT THIS DOES THEN IS KICKS THE CLOSED LOW OUT
SLOWLY ENE AND ANOTHER CLOSED 500 MB LOW FORMS OVER THE NORTHERN
PLAINS TUE NIGHT AND DIGS SE INTO THE MISSOURI RIVER VALLEY NEAR
SIOUX CITY IA 00Z THU WHILE THE OTHER LOW IS IN CENTRAL LOWER
MICHIGAN. DEEPER MOISTURE DOES NOT ARRIVE UNTIL TUE NIGHT ALONG WITH
SOME BETTER DYNAMICS ACCORDING TO THE NAM. GFS IS FAIRLY SIMILAR TO
THE NAM EXCEPT BRINGS PCPN IN A BIT QUICKER. BASICALLY...WITH MODELS
STILL NOT CONSISTENT ON SOLUTION...WILL NOT MAKE VERY MANY CHANGES
TO THE GOING FORECAST. KEPT LIKELY POPS IN FOR WED THROUGH THU WITH
DECENT MOISTURE AROUND. ONLY CHANGE I DID MAKE WAS TO REMOVE SNOW
FROM WED AS COLD AIR DOES NOT COME IN UNTIL WED NIGHT. SYSTEM REALLY
DOES NOT HAVE MUCH COLD AIR TO WORK WITH AND WILL HAVE TO
MANUFACTURE ITS OWN COLD AIR TO DO SO.

IN THE EXTENDED...CONTINUED TO GO WITH THE 00Z ECMWF FOR THIS
FORECAST PERIOD AS IT HAS BEEN THE MOST CONSISTENT MODEL FOR THE
PAST SEVERAL DAYS. ECMWF SHOWS A TROUGH AND CLOSED LOW AFFECTING THE
AREA FOR THU AND THEN RIDGING FOR FRI AND SAT AND INTO SUN AS WELL.
DID NOT MAKE ANY CHANGES TO THE EXTENDED AT ALL. STILL HAVE LIKELY
POPS IN FOR THU AND THEN DRY FOR FRI NIGHT THROUGH SUN EVEN AS A
COLD FRONT MOVES THROUGH ON SUN. TEMPERATURES CONTINUE TO BE MILD
AND NORMAL TO SLIGHTLY ABOVE NORMAL.

&&

.AVIATION /FOR THE 18Z TAF ISSUANCE/...

THE REMAINING MIST SHOULD DISSIPATE EARLY THIS AFTERNOON. A FEW
SPRINKLES ARE SHOWING UP ON RADAR AND WERE REPORTED AT KCMX...SO
HAVE ADDED IT TO THE TAF. AFTER THE MIST DISSIPATED...BOTH SITES
WILL BE VFR UNTIL LATER TONIGHT WHEN FOG WILL LIKELY REDEVELOP AS
LOW LEVEL HUMIDITY INCREASES OVER THE AREA. AT BOTH LOCATIONS
SIMILAR CONDITIONS TO LAST NIGHT WILL AGAIN OCCUR WITH DOWNSLOPING
SOUTHERLY WINDS LIMITING LOWER VISIBILITIES AND CEILINGS TO LIFR.

LLWS CAN BE EXPECTED AT BOTH TAF SITES AFTER SUNSET UNTIL LATE
MORNING ON MONDAY WHEN THE LOW LEVEL JET SHIFT EAST.

&&

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

WITH LAKE SUPERIOR IN BETWEEN LOW PRESSURE OVER THE CENTRAL PLAINS
AND THE HIGH OVER THE NORTHEAST STATES...SOUTHERLY WINDS TO 25 KNOTS
WILL PREVAIL INTO MONDAY MORNING. A FEW WIND GUSTS TO 28 KNOTS WILL
BE POSSIBLE TONIGHT MAINLY OVER THE EASTERN LAKE. WINDS WILL REMAIN
UNDER 20 KNOTS INTO WEDNESDAY...WHEN A STORM SYSTEM APPROACHES THE
UPPER GREAT LAKES AND WINDS BEGIN TO INCREASE OUT OF THE NORTH AND
NORTHEAST WITH GALES POSSIBLE LATE WEDNESDAY THROUGH FRIDAY MORNING.
LOCALLY DENSE PATCHY FOG IS POSSIBLE TONIGHT ACROSS LAKE SUPERIOR.

&&

.MQT WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

SYNOPSIS/SHORT TERM...DLG
LONG TERM...07
AVIATION...DLG
MARINE...DLG




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