[LeArc] Forecast Discussion : MLI@ 6/11/2003 3:13:41 AM

[learc@mailman.qth.net]

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


FXUS63 KDVN 110809
AFDMLI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
300 AM CDT WED JUN 11 2003

ZONAL FLOW NOW IN PLACE OVER U.S. STRONGEST FLOW IS LOCATED ALONG 
THE CANADIAN BORDER WITH HEIGHT FIELDS RELAXING FURTHER SOUTH.  AT 
THE SURFACE A WEAK SURFACE LOW WAS LOCATED OVER NRN MICHIGAN WITH A 
COLD FRONT TRAILING TO THE SW THROUGH NRN IL AND NRN MO.  MID LEVEL 
S/W OVER THE SRN PLAINS WAS INTERACTING WITH UNSTABLE AIRMASS AHEAD 
OF FRONT RESULTING A COUPLE OF THUNDERSTORM COMPLEXES ACROSS SRN MO 
AND IL. 

MODELS HAVE COME INTO BETTER AGREEMENT ON OVERALL SYNOPTIC PATTERN 
FOR THE NEXT COUPLE OF DAYS.  COLD FRONT PROGGED TO STALL OVER 
CENTRAL/SRN MO BY THIS AFTERNOON AND REMAIN THERE THROUGH FRIDAY 
MORNING.  S/W ENERGY MOVING THE WEAK MID LEVEL FLOW OVER THE 
SOUTHERN PLAINS AND LOWER MS VALLEY WILL SPIN UP SURFACE WAVES ALONG 
THE STALLED BOUNDARY.  MODELS ARE IN GOOD AGREEMENT WITH THE INITIAL 
WAVE...MOVING IT THROUGH EAST CENTRAL MO AND SRN IL FROM LATE THIS 
AFTERNOON INTO THURSDAY MORNING.  BY FRIDAY MORNING MODELS START TO 
DIVERGE AS THEY HAVE TROUBLE HANDLING S/W ENERGY MOVING THROUGH WEAK 
FLOW OVER THE SOUTHERN HALF OF THE COUNTRY.  GFS OBVIOUSLY HAVING 
FEEDBACK ISSUES BY 12Z FRIDAY.  UKMET/ETA LOOK MORE REASONABLE.  

FOR THE SHORT TERM THE MAIN CONCERN WILL BE CLOUD TRENDS AND TEMPS 
FOR TODAY.  LIGHT NORTHERLY FLOW OVER UPPER MS VALLEY WAS PUSHING 
STRATUS DECK SOUTH THROUGH NORTHEAST IOWA AND SOUTHERN WI EARLY THIS 
MORNING.  AS OF 07Z LEADING EDGE OF STRATUS WAS ALONG AN 
KAXA...KCCY...KEFT LINE.  IN ADDITION PATCHY SC HAS BEEN PERSITENT 
OVER THE NORTHERN HALF OF CWA SO FAR THIS MORNING...AND DEBRIS CI 
FROM MO CONVECTION HAS BEEN SKIRTING THE SOUTHEASTERN COUNTIES.  
EXPECT STRATUS TO SPREAD OVER AT LEAST THE NORTHERN THIRD OF THE CWA 
THIS MORNING BEFORE LOW LEVEL FLOW BECOMES MORE EASTERLY.   STRONG 
JUNE SUN SHOULD THEN ERODE THE STRATUS DECK QUICKLY EARLY THIS 
AFTERNOON. REST OF CWA SHOULD SEE CU DEVELOPING BY EARLY AFTERNOON 
PER MODEL SOUNDINGS. FWC NUMBERS LOOK REASONABLE FOR TODAYS MAXES.
WILL ALSO CONTINUE SLGT CHC WORDING SOUTH THIS AFTERNOON...WITH 
POSSIBILITY OF MO CONVECTION BRUSHING SOUTHERN MOST CWA.  

OTHER THAN LOW POPS SOUTH THIS EVENING WILL KEEP FCST DRY OVERNIGHT.
THURSDAY WILL LIMIT POPS TO WESTERN CWA LATE IN THE DAY AS TAIL OF 
NRN STREAM S/W SWINGS THROUGH. OVERNIGHT THURSDAY INTO FRIDAY 
MORNING WILL KEEP CHANCE POPS OVER SOUTHERN HALF OF CWA IN RESPONSE 
TO SURFACE WAVES MOVING ALONG BOUNDARY TO THE SOUTH.  FOR THE REST 
OF THE WEEKEND WILL KEEP CHANCE WORDING OVER THE CWA WITH 
UNCERTAINTY OF LOCATION OF FRONTAL BOUNDARY.  

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

$$
DLF