[LeArc] Forecast Discussion : MLI@ 6/9/02 2:27:28 PM

[learc@mailman.qth.net]

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


FXUS63 KDVN 091926
AFDMLI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
225 PM CDT SUN JUN 9 2002

SYNOPTIC PICTURE THIS AFTERNOON SHOWS TROF OVER ROCKIES AT 500H...WITH
552 LOW OVER SOUTHERN IDAHO...AND LARGE HIGH OVER SOUTHEAST HALF OF
U.S.  AT THE SURFACE...A 995 LOW IS OVER NORTHEAST COLORADO...AND A
HIGH OVER THE CAROLINAS...WITH MODERATE SOUTHERLY FLOW ACROSS MIDWEST...
BRINGING IN HIGHER DEW POINTS.  CONVECTION BREAKING OUT ACROSS SOUTH
CENTRAL ILLINOIS IS IN RESPONSE TO UPPER DIVERGENCE COMBINED WITH HIGH
CAPES/DEW POINTS.

THE MODELS INITIALIZED WELL AT 12Z...WITH THE AVN AND NGM DOING BEST
WITH COLORADO SURFACE LOW.  AVN IS HANDLING DEW POINTS THE BEST...WITH
ETA O.K...AND NGM TOO DRY.  THE AVN IS ALSO HANDLING ILLINOIS PRECIP
TREND THE BEST.

THE PRIMARY FORECAST CONCERN IS TROF SINKING SOUTHEAST OVER THE AREA
TUESDAY...AND ASSOCIATED PRECIP.  MODELS ARE IN SIGNIFICANT
DISAGREEMENT OVER THE HANDLING OF THIS FEATURE THRU 48 HOURS.

IN THE SHORT TERM...THE MODELS AGREE ON BRINGING A 500H SHORT WAVE OVER
THE FORECAST AREA LATE TONIGHT INTO MONDAY.  THAT'S ABOUT AS FAR AS
THEIR AGREEMENT GOES HOWEVER.  THE AVN BRINGS THE SURFACE TROF THRU THE
FORECAST AREA TUESDAY...WHILE THE NGM AND ETA HOLD IT BACK WEST THRU 48
AND 60 HOURS RESPECTIVELY. CONTRARY TO THIS THE MEDIUM RANGE MODELS
AGREE WITH THE AVN.  HIGH SURFACE DEW POINTS...AROUND 70...MONDAY AND
TUESDAY...COMBINED WITH MODERATE CAPES AND LI'S...ESPECIALLY TUESDAY...
WILL PROVIDE TRIGGER FOR SCATTERED CONVECTION.

WILL INCREASE POP'S TONIGHT FOR 500H SHORT WAVE.  WILL ALSO INCREASE
MONDAY'S POP'S...PER HIGHER FWC/MAV GUIDANCE.  WILL CONTINUE TREND OF
STAYING ABOVE GUIDANCE ON TEMPS MONDAY AND TUESDAY.

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

REA