[LeArc] Forecast Discussion : MLI@ 6/10/02 2:52:29 AM

[learc@mailman.qth.net]

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


FXUS63 KDVN 100752
AFDMLI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
252 AM CDT MON JUN 10 2002

LATEST ANALYSIS INDICATING SURFACE LOW OVER NE COLORADO...WITH STRONG
SOUTHERLY FLOW ACROSS FORECAST AREA.  GOOD PRESSURE FALLS OVER SE MT
WHERE THERE IS SOME THUNDERSTORM ACTIVITY. STRONG UPPER LEVEL LOW AT
UPPER LEVELS QUITE WOUND UP...WITH FALLS AT 500 MB TO ITS WEST.
SHORTWAVE MOVING ACROSS MO TOWARDS CWA NOT VERY STRONG...BUT SHOWS BEST
ON SATELLITE IMAGERY RATHER THAN 00Z UPPER LEVEL SOUNDINGS.

MAIN CONCERN IS THE MOVEMENT OF THE SURFACE FRONT TUESDAY AND TUESDAY
NIGHT.  MODELS CONTINUE TO HAVE BIG DIFFERENCES IN THE POSITIONING OF
THIS FRONT...WITH LITTLE CHANGE FROM PREVIOUS RUNS.

00Z MODELS APPEAR TO HAVE INITIALIZED FAIRLY WELL...PLACING THE SURFACE
LOW FAIRLY WELL AT 06Z...THOUGH PRECIP TRENDS OVER CWA COULD BE BETTER
HANDLED.   ETA DOING BEST WITH SFC DEWPOINTS...AVN TOO DRY OVER THE
HIGH PLAINS AND TOO WET HERE.

TODAY...WILL HAVE TO DEPEND ON SHORT TERM FORECASTING TECHNIQUES TO
DETERMINE LOCATION/TIMING OF PRECIPITATION TODAY.  MODELS ARE
CONSISTENT IN BRINGING THE SHORTWAVE RESPONSIBLE FOR THE CURRENT
SHOWERS SOUTH ACROSS CWA OVERNIGHT...THEORETICALLY ONLY AFFECTING THE
NORTH HALF AFTER 12Z.  ON SUNDAY THE CWA WAS CAPPED BY WARM TEMPS AT
700 MB...WHICH ARE COOLED AFTER THE PASSAGE OF THIS SHORTWAVE...SO
THERE SHOULD BE SCATTERED DEVELOPMENT IN THE AFTERNOON ONCE SUNSHINE
BREAKS THROUGH CLOUD COVER AFTER THE WAVE PASSES.

TONIGHT...DURING THE EVENING THERE SHOULD BE SOME LINGERING TSRA
BEFORE SUNSET...AND THEN AS THE FRONT APPROACHES TSRA/SHRA SHOULD MOVE
BACK OVER CWA.  CHANCE POPS STILL LOOK GOOD FOR NOW...THOUGH WILL LOWER
POPS A LITTLE IN THE SOUTHEAST.  ALL IS DEPENDENT ON THE MOVEMENT OF
THE SURFACE FRONT.

TUESDAY AND TUESDAY NIGHT...LIKELY POPS STILL LOOK GOOD...WITH THE FRONT
IN THE VICINITY AND PLENTY OF INSTABILITY TO THE SOUTH.  BETTER POPS ARE
LIKELY TO BE TOWARDS THE NORTH...BUT FOR NOW DUE TO THE UNCERTAINTY OF
THE MODEL SOLUTIONS WILL NOT LOWER POPS IN SOUTHEAST.

DUE TO SENSITIVITY OF THE RIVERS IN THIS AREA...WILL HAVE TO KEEP A
CLOSE EYE ON QPF VALUES.  HOWEVER...FOR NOW IT LOOKS AS IF
THUNDERSTORMS SHOULD KEEP MOVING FAIRLY WELL...SO FLASH FLOOD THREAT
FAIRLY LOW. DESPITE SLOW MOVEMENT OF FRONT...QPF IN ANY ONE AREA SHOULD
NOT BE MORE THAN A HALF INCH FOR A BASIN AVERAGE.  THIS WILL SLOW DROP
OF RIVERS...BUT HOPEFULLY NOT CAUSE FURTHER FLOODING.

WEDNESDAY...EARLIER IT APPEARED THAT THE FRONT WOULD SCOOT SOUTH
FAIRLY QUICKLY ONCE IT GOT THROUGH CWA.  HOWEVER...LATEST MODELS
KEEPING IT AROUND AND WILL EXPAND POPS TO ALL DAY...THOUGH BEST POPS
ACROSS SOUTH.

NO CHANGES TO MAKE TO EXTENDED ATTM.

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

LRE