[LeArc] Forecast Discussion : MLI@ 2/13/03 3:04:27 AM

[learc@mailman.qth.net]

The following weather message is provided by McDonough County E.S.D.A.


FXUS63 KDVN 130913
AFDMLI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
315 AM CST THU FEB 13 2003

BUSY BUSY MORNING WITH LITTLE ONGOING IN THE NEAR TERM...BUT LOTS TO 
THINK ABOUT IN THE 24 TO 60 HR TIME FRAME.  SURFACE RIDGE STILL 
SITTING TO THE SOUTHWEST OF THE CWFA THIS MORNING...AND WINDS HAVE 
DROPPED OFF QUITE A BIT TO ALLOW TEMPS TO DROP OFF...ESPECIALLY IN 
THE NORTHEASTERN PARTS OF THE CWA.  SOUTHWEST AREAS STILL IN THE 
UPPER 20S...WITH DUBUQUE DOWN TO 11 AS OF 08Z.  ALOFT...STRONG 
NW-SE ORIENTED JET PASSING OVER THE AREA...WITH A RIDGE OVER THE 
WESTERN ROCKIES.  850 MB SHOWING THAT LOW LEVEL MOISTURE BEGINNING 
TO GET DRAWN NORTHWARD IN SOUTHERLY FLOW.  SATELLITE SHOWING OUR 
FRIDAY SYSTEM JUST NOW BEGINNING TO MOVE ON SHORE...WITH UA NETWORK 
ONLY BEGINNING TO SAMPLE IT.  AIRCRAFT REPORTS HAVE DELINEATED THE 
FLOW AROUND THE DEVELOPING SYSTEM FAIRLY WELL.  

MAIN CONCERN THIS FORECAST IS THE FRIDAY/FRIDAY NIGHT SYSTEM.

00Z MODELS FINALLY COMING IN LINE WITH THE FORECAST OF THIS 
SYSTEM...AND ETA SOLUTION APPROACHING AVN SOLUTION WHICH HAS HAD 
BEST CONTINUITY ALL ALONG.  STILL PREFER THE AVN SOLUTION BIG 
PICTURE...THOUGH THINK THAT THERMAL PARAMETERS ON THE ETA MAY BE 
MORE IN LINE WITH WHAT WILL HAPPEN.  AVN IS COLDER...AND 
DE-EMPHASIZES THE WARM LAYER THAT DEVELOPS ALOFT...WHERE THE ETA 
BRINGS THE WARM LAYER MUCH FARTHER NORTH AND IS SIGNIFICANTLY 
DEEPER.  QPF VALUES ON AVN LOOK MUCH BETTER THAN ETA...SO WILL GO 
CLOSER TO THAT. 

TODAY WEATHER IS QUIET...THOUGH SOME CLOUDS WILL MOVE INTO THE FAR 
NORTH...AND THEN THIN OUT DURING THE DAY.  SNOW ACROSS THE FAR NORTH 
SHOULD FINALLY DISAPPEAR...THOUGH WILL KEEP TEMPS COOL WHERE SNOW IS 
STILL ON GROUND...JUST ABOVE AVN MOS GUIDANCE.  ELSEWHERE...WILL BE 
GOING PRETTY WARM...AND CLOSER TO FWC/ETA MOS GUIDANCE OR JUST ABOVE.

TONIGHT CLOUDS MOVE IN FROM DEVELOPING SYSTEM...LOTS OF CIRRUS 
DURING THE EVENING AND THICKENING AND LOWERING BY MORNING.  HAVE 
DOUBTS ABOUT PRECIP MANAGING TO MAKE IT INTO ALL BUT THE FAR 
SOUTHWEST BY MORNING...AND WILL DELAY PRECIP IN GOING FCST.  TEMPS 
SHOULD BE PRETTY WARM...AND WILL GO UPPER 20S AT WARMEST FAR SOUTH.  

FRIDAY THE PRECIP REALLY MOVES IN...WITH WARM AIR ALOFT AND 
SUB-FREEZING TEMPS AT THE SURFACE TO CAUSE A PERIOD OF RAIN/FREEZING 
RAIN MIX IN THE MORNING FROM ABOUT CID-MLI AND SOUTH.  LOCATIONS 
ALONG HWY 34 AND SOUTH WITH THEN CHANGE OVER TO ALL RAIN FOR A FEW 
HOURS...THEN THEN BEGIN SWITCHING BACK TO ZR/IP/RAIN MIX BY LATE 
AFTERNOON...AND THE SLOWLY SWITCH TO SNOW FROM MID EVENING ON FROM 
NORTHWEST TO SOUTHEAST.  LOCATIONS BETWEEN HIGHWAY 34 AND HIGHWAY 
30...INCLUDING THE INTERSTATE 80 CORRIDOR...ARE LOOKING AT STARTING 
OUT MORE MIXED WITH ZR/IP/SN. DON'T THINK WILL SWITCH TO ALL RAIN AT 
ALL...BUT WILL BEGIN CHANGING TO SN BY AFTERNOON AROUND CID...AND 
THEN DURING THE EVENING CONTINUE TO BECOME ALL SNOW.  ALL IN 
ALL...IT'S GOING TO BE A MESSY SITUATION FOR THIS AREA.  HAVE GONE 
WITH A WINTER STORM WATCH FOR LOCATIONS ALONG AND SOUTH OF HIGHWAY 
30...OR CID-SQI AND SOUTH.  FRIDAY NIGHT AFTER MIDNIGHT THERE SHOULD 
BE SNOW EVERYWHERE...BUT DYNAMICS DROP OFF QUICKLY AND NOT MUCH QPF 
EXPECTED.  SNOW AMOUNTS FRIDAY EVENING AND OVERNIGHT FROM ABOUT 
WASHINGTON TO MONMOUTH AND NORTH COULD BE IN THE 1 TO 3 INCH RANGE.

NOT MUCH TO SAY FOR THE REMAINDER OF THE PERIOD...WILL BE INCREASING 
CLOUDS FOR SUNDAY AS A WEAK LITTLE CLIPPER SYSTEM MOVES ACROSS WI.  
NO OTHER CHANGES ARE EXPECTED.

.DVN...
IA....WINTER STORM WATCH FOR FRIDAY AND FRIDAY NIGHT ALONG AND SOUTH 
OF A LINE FROM VINTON TO CLINTON.
IL...WINTER STORM WATCH FOR FRIDAY AND FRIDAY NIGHT ALONG AND SOUTH 
OF A LINE FROM CLINTON TO STERLING/ROCKFALLS.
MO...WINTER STORM WATCH FOR FRIDAY AND FRIDAY NIGHT.

$$

LRE