[LeArc] Forecast Discussion : MLI@ 6/12/02 2:56:13 AM

[learc@mailman.qth.net]

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


FXUS63 KDVN 120755
AFDMLI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
255 AM CDT WED JUN 12 2002

BUSY WEATHER THIS MORNING WITH THE MCS ACROSS SOUTHERN CWA AND 
FURTHER SOUTH.  THIS MCS HAS CAUSED SOME FLOODING PROBLEMS ACROSS 
THE SOUTH...WITH A PORTION HAVING RECEIVED MORE THAN 6 INCHES IN THE 
LAST 24 HOURS.  SURFACE FRONT LINGERS OVER NORTHWESTERN PORTIONS OF 
THE CWA...EXTENDING FROM JUST NORTH OF KMCI...TO BETWEEN KCID AND 
KALO TO NEAR KMSN.  UPPER LEVELS CONTINUE TO SHOW 850 MB FRONT 
ACROSS THE MIDWEST...EXTENDING FROM SOUTH OF KLBF...TO CENTRAL 
MICHIGAN.   STRONG SOUTHERLY FLOW/LLJ AT 850MB HELPING TO FUEL 
STORMS.  UPPER LEVEL LOW CONTINUES TO MOVE VERY SLOWLY...WITH ONLY 
MODERATE HEIGHT FALLS TO ITS EAST.  

MAIN CONCERNS THIS MORNING ARE WHERE SHOWERS AND THUNDERSTORMS WILL 
OCCUR OVER THE NEXT 36-48 HOURS.  MODELS AGAIN SHOWING HIGH 
VARIABILITY OVER PLACEMENT OF PRECIPITATION...WITH PROBLEMS WITH 
PLACEMENT OF SURFACE FRONT.

00Z MODELS APPEAR TO HAVE INITIALIZED FAIRLY WELL...BUT BY 12Z THERE 
ARE BIG PROBLEMS AT THE SURFACE WITH WHERE PRECIPITATION IS.  AVN 
APPEARS TO BE BADLY AFFECTED BY CONVECTIVE FEEDBACK...ESPECIALLY 
TONIGHT.  ETA TOO LOW ON QPF...AND APPEARS TO HAVE SURFACE LOW TOO 
FAR NORTH.  LIKE SOLUTION THAT AVN...UKMET AND NGM FAVOR WITH A 
SURFACE WAVE MOVING ACROSS NORTHERN MO INTO CENTRAL IL BETWEEN KUIN 
AND KSTL.  THIS SURFACE PATTERN IS FAVORABLE FOR HEAVY RAIN OVER THE 
SOUTHERN HALF OF THE CWA.  FOR NOW WILL HOLD OFF ON FFA...THOUGH DAY 
SHIFT MAY HAVE TO ISSUE WHEN IT BECOMES MORE CERTAIN WHERE HEAVY 
RAIN AXIS WILL FALL.  

TODAY...FEEL THAT MUCH OF CWA WILL BE DRY FOR AT LEAST THE MORNING 
HOURS.  CURRENT MCS SHOULD BE OUT OF CWA BY OR SHORTLY AFTER 
ISSUANCE OF PACKAGE...SO NO NEED FOR MENTION OF MORNING PRECIP.  ANY 
NEW DEVELOPMENT SHOULD BE LIMITED TO THE LATE AFERNOON...AND IS MORE 
LIKELY TO AFFECT AREAS IN THE FAR SOUTH.  WILL KEEP CHANCE 
POPS...BUT LIMITED TO SOUTHERN TWO THIRDS OF CWA.  TEMPS WILL BE 
NEARLY AS COOL AS YESTERDAY...AND GOING FCST LOOKS FAIRLY GOOD. 

TONIGHT...MAIN SHOW OF SHOWERS AND THUNDERSTORMS OCCURRS...WITH MAIN 
AXIS OF PRECIPITATION SOMEWHERE ACROSS SOUTHERN HALF OF CWA.  AS 
EARLIER DISCUSSED...WILL BE HOLDING OFF ON FFA...MAINLY DUE TO LACK 
OF CONFIDENCE IN MODEL QPF AND POSITIONING. COOLER AIR BEGINS TO 
FILTER INTO THE REGION...AND WILL BE GOING WITH COLDER MAV 
TEMPS...AND SLIGHTLY WARMER THAN GOING TEMPS.

THURSDAY AND THURSDAY NIGHT...THE UPPER LEVEL COLD POOL MOVES ACROSS 
THE AREA...CAUSING SHOWERS AND THUNDERSTORMS DURING THE AFTERNOON 
AND EARLY EVENING HOURS.  THE ACTUAL COLD POOL COMES ACROSS CLOSER 
TO MIDNIGHT...SO WILL LINGER SHOWERS INTO EVENING HOURS.  WILL KEEP 
POPS IN SLIGHT CHANCE CATEGORY.  TEMPS TO BE VERY COOL WITH GOOD 
NORTHWEST FLOW.  GOING FORECAST IS COOLER THAN GUIDANCE AND WILL 
CONTINUE THIS TREND.

FRIDAY...SIMILAR OCCURRENCE TO THURSDAY...BUT WITH LESS ENERGY TO 
IT...AND WILL LEAVE JUST SHOWERS IN GOING FORECAST.

NO CHANGES PLANNED TO LATER PERIODS.

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

LRE