[LeArc] Forecast Discussion : MLI@ 6/29/2003 3:29:28 AM

[learc@mailman.qth.net]

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


FXUS63 KDVN 290826
AFDMLI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
325 AM CDT SUN JUN 29 2003

LATEST ANALYSIS INDICATING A WEAK SURFACE FRONT OVER EASTERN AND 
SOUTHERN IOWA...DRAPED FROM NEAR KDEH TO JUST WEST OF KCID...THEN 
DSOUTHWEST TO KICL.  SOME WEAK SHOWERS/SPRINKLE ACTIVITY TO THE EAST 
OF THIS FRONT...BUT OTHERWISE LITTLE OF INTEREST ACROSS THE CWA THIS 
MORNING.  LARGE MCS COMPLEX OVER KANSAS WELL SUPPORTED BY GOOD 850MB 
JET...AND UPPER LEVEL TROUGH AXIS ALOFT. GOOD THERMAL AND MOISTURE 
AXIS ACROSS KANSAS AND NORTHERN MISSOURI AT 00Z...WHICH SHOULD KEEP 
THIS MCS TREKKING EAST DURING THE DAY TODAY.  

12Z MODELS APPEAR TO HAVE INITIALIZED REASONABLY WELL.  AS OF 06Z 
THE AVN HAS PICKED UP A QPF BULLSEYE...PROBABLY FEEDBACK...AND 
GENERALLY LOOKS TOO STRONG WITH ITS HANDLING OF THE INVERTED SURFACE 
TROUGH NEXT 24 TO 48 HOURS.  HAVE LEANED PRETTY HEAVILY ON THE ETA 
THIS FORECAST.  

THE CURRENT SPRINKLES ACROSS THE CWA SHOULD HAVE DISSIPATED AND/OR 
MOVED EAST OUT OF THE AREA BY 6 AM...SO DECIDED TO LEAVE THEM OUT OF 
THE ZFP FOR NOW...AND WILL HANDLE WITH A NOWCAST TIL THEY 
DISSIPATE.  FRONT DROPS SOUTHEAST...AND BY 18Z IS ACROSS THE 
SOUTHERN FRINGES OF THE CWA.  SEGMENTS OF THE DECAYING MCS MAY 
MANAGE TO MAKE IT THIS FAR EAST THIS AFTERNOON ALONG THIS 
BOUNDARY...AND SOME NEW CONVECTION MAY FORM ALONG THE BOUNDARY.  
SO...HAVE A SLIGHT CHANCE OF PRECIP ACROSS FAR SOUTH DURING THE DAY 
TODAY.  TEMPS TO BE SLIGHTLY WARMER TODAY THAN THEY WERE YESTERDAY.  

TONIGHT A FRESH MCS RE-INITIATES OVER KANSAS...PROPAGATING EAST 
SLOWLY OVERNIGHT.  THE WEAK SURFACE BOUNDARY HANGS UP ACROSS 
NORTHERN MISSOURI WITH NOTHING NEW TO PUSH IT FURTHERN EAST.  ONCE 
AGAIN...THOUGH BULK OF PRECIP SHOULD STAY TO THE SOUTH AND 
WEST...HAVE DECIDED TO GO WITH A SLIGHT CHANCE ACROSS THE FAR SOUTH 
WITH THE BOUNDARY STILL IN THE VICINITY.  ...LE

THERE IS A RATHER LOW DEGREE OF CONFIDENCE IN WEATHER WE WILL SEE 
SHOWERS AND STORMS MONDAY AND TUESDAY.  THE ETA...AS WELL AS MOST 
OTHER MODELS...INITIALIZED FAIRLY WELL IN DEPICTING THE IMPRESSIVE 
MCS ACROSS THE WESTERN PLAINS. ALL SHORT TERM MODELS INDICATE THAT 
THIS FEATURE WILL BE SLOW TO DISSIPATE...AND WILL CONTINUE TO BRING 
PRECIP TO AREAS WHERE IT TRACKS. HOWEVER...AS USUAL...THE TRACKS ARE 
NOT ALIKE.  THE ETA IS THE FURTHEST NORTH WITH THE DISSIPATING VORT 
MAX...AND THE SLOWEST...LINGERING IT THROUGH TUESDAY EVENING.  THE 
NGM AND GFS ARE SLIGHTLY FASTER AND FURTHER SOUTH.  FEEL THAT WITH 
THE BOUNDARY HUNG UP JUST SOUTH OF THE CWA NOW...THE CURRENT 
FORECAST POPS OF 20S CENTRAL TO 40 SOUTH MONDAY IS ON TRACK. WILL 
ADD SLIGHT CHANCES SOUTHERN THIRD TUESDAY AFTERNOON AND EVENING 
...AS GFS ALSO SUPPORTS ISOLATED PRECIP THROUGH AFTERNOON 
INSTABILITY AND A WEAK UPPER WAVE.  

IN THE EXTENDED...(WEDNESDAY THROUGH SATURDAY)
WARM AND HUMID PATTERN CONTINUES TO BE WELL ADVERTISED BY ALL 
EXTENDED MODEL SOLUTIONS. FAIRLY GOOD AGREEMENT ALSO WITH BRINGING A 
POTENT WAVE THROUGH SOUTHERN CANADA WEDNESDAY AND THURSDAY.  THIS 
SHOULD DRIVE A COLD FRONT DOWN TOWARD THE CWA THURSDAY/NIGHT.  
SEASONALLY WEAK FLOW IS PROGGED AFTER THE THIS TIME...AND WITH THE 
BOUNDARY HUNG UP SOMEWHERE WITHIN A DEGREE OF LATITUDE OF INTERSTATE 
80...CHANCE OF THUNDER SEEMS QUITE REASONABLE.  ...ERVIN 

DVN...
IA...NONE.
IL...NONE.
MO...NONE.

$$