000 
FXUS63 KDMX 220834
AFDDSM

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DES MOINES IA
300 AM CST FRI FEB 22 2002

FORECAST CHALLENGES IN SHORTER TERM MAINLY WITH TEMPS AND CLOUDS AS 
STRONG WAA TAKES OVER.  PRECIPITATION...ALBEIT LIGHT...BECOMES MORE 
OF A CONCERN INTO THE WEEKEND AS COLD AIR MOVES INTO THE REGION.  
CURRENTLY...RIDGE AXIS IS SLIDING INTO THE STATE WITH WINDS TAPERING 
OFF NICELY.  LAST REMNANTS OF LOW CLOUDS HAVE FINALLY EXITED THE FAR 
SOUTHEAST AS CYCLONIC FLOW SUBSIDES.  

MODELS REMAIN CONSISTENT WITH STRONG WARM ADVECTION BEGINNING THIS 
AFTERNOON AS SFC RIDGE MOVES EAST OF IA.  SOME HIGH CLOUDINESS ARE 
EXPECTED THIS MORNING BUT SHOULD THICKEN BY AFTERNOON AS MID 
LEVELS START TO SATURATE.  TEMPERATURES SHOULD INITIALLY BE SLOW TO 
REBOUND WITH LIGHT WINDS BUT AS WINDS INCREASE FROM THE SOUTH... 
READINGS SHOULD TAKE OFF BY THIS AFTERNOON.  HAVE GONE WITH WARMER 
MAV TODAY AS FWC COOLER THAN THURSDAY/S HIGHS WHEN CAA WAS 
OCCURRING.  GOOD Q-G FORCING OVERNIGHT AS WAA PERSISTS.  LACK OF 
MOISTURE WILL LIMIT ANY WEATHER TO CLOUDINESS...POSSIBLY A FEW 
SPRINKLES OR FLURRIES NORTH.  HAVE GONE ON HIGH END OF GUIDANCE 
OVERNIGHT AS CLOUDS AND WAA SHOULD KEEP READINGS FROM TAILING OFF 
MUCH.

THERMAL RIDGE TO PASS OVER STATE ON SATURDAY AS STRONG SOUTHERLY 
FLOW PERSISTS.  AMOUNT OF CLOUDINESS WILL PLAY BIG INTO EVENTUAL 
HIGHS FOR THE DAY WHICH COULD NEAR RECORD LEVELS IN SOME LOCATIONS.  
IT APPEARS NOW THAT NORTHERN IOWA SHOULD SEE THE MOST CLOUDINESS 
DURING THE DAY WITH MORE SUN FARTHER SOUTH.  WL CONT ON THE HIGH 
SIDE OF GUIDANCE AS CONDITIONS FAVORABLE FOR DECENT WARMUP. CHANGES 
BEGIN TO OCCUR ON SATURDAY NIGHT AS COLD FRONT MOVES INTO STATE.  
TIMING DIFFERENCE DEVELOP BETWEEN ETA/AVN IN MOVEMENT OF FRONT AND 
WILL AVERAGE THE DIFFERENCES THIS FAR OUT.  SHOULD SEE INCREASING 
CHANCES FOR PRECIPITATION LATE SAT NIGHT INTO SUNDAY...ESPECIALLY 
ACRS THE NORTH AS WAVE PASSES ALONG THE FRONT THROUGH IA.  TEMPS WL 
CRASH BEHIND THE FRONT WITH ONLY MINOR REBOUND ON SUNDAY AS ANY 
SOLAR HEATING WL BE FIGHTING STRONG COLD ADVECTION.  LITTLE CHANGE 
TO EXTENDED AS BROAD CYCLONIC FLOW SHOULD CONTINUE TO PRODUCE 
CLOUDINESS ALONG WITH SCATTERED FLURRIES.  TEMPS SHOULD ACTUALLY BE 
WELL BELOW NORMAL FOR THE FIRST TIME IN QUITE A WHILE EARLY NEXT 
WEEK. 

.DSM...NONE

COGIL