[LeArc] Forecast Discussion : MLI@ 6/28/2003 5:02:57 PM

[learc@mailman.qth.net]

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


FXUS63 KDVN 282143
AFDMLI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
430 PM CDT SAT JUN 28 2003

MESOSCALE VORT MAX SHIFTING INTO MI ATTIM. SCATTERED CONVECTION HAS
DEVELOPED ALONG OUTFLOW ARCING FROM ROUGHLY CLINTON IA TO
PRINCETON IL TO SOUTH OF CHICAGO. MID LEVEL FORCING ABSENT...WHICH
SUPPORTS PULSE TYPE STORMS WITH ISOLATED HAIL/WIND.
SCATTERED CONVECTION ALSO DEVELOPING ALONG WEAK SURFACE TROUGH 
EXTENDING FROM NEAR DUBUQUE TO NEWTON. 12Z UPPER AIR ANALYSIS SHOWS
NORTHWEST FLOW CONTINUING TO DOMINATE NATION/S MIDSECTION.
NEXT DISTURBANCE IN THE FLOW DIVING THROUGH EASTERN MT AND WESTERN ND
POSES A CONCERN LATER IN SHORT TERM.

TONIGHT...CONVECTION WILL GRADUALLY DIMINISH WITH LOSS OF HEATING.
DISTURBANCE DIVING THROUGH MT WILL INTERACT WITH 
TAIL OF SURFACE TROUGH/FRONT AND LLJ TO GENERATE CONVECTIVE 
COMPLEX IN THE CENTRAL PLAINS. CORFIDI VECTORS YIELD S/SE MOVEMENT 
WHICH WOULD TAKE COMPLEX INTO SOUTHERN PLAINS. JET MAX
PROGGED TO DIVE THROUGH UPPER MIDWEST WITH LEFT EXIT REGION AND
OMEGA BRUSHING FAR NORTH...SO KEPT SLIGHT CHANCE POPS IN NORTH 
OF U.S. HIGHWAY 30

SUNDAY...DIFFUSE BOUNDARY IN VICINITY OF THE FAR SOUTHERN ZONES.
MID LEVEL FORCING WELL TO OUR NORTH AND SOUTH WITH
AREA IN BETWEEN...SO LITTLE IN THE WAY OF UPPER SUPPORT TO AID PCPN 
DEVELOPMENT. HOWEVER...WITH BOUNDARY HANGING NEARBY CAN/T 
RULE OUT AND ISOLATED SHOWER OR STORM IN FAR SOUTH...SO KEPT PREVIOUS
SHIFTS TOKEN 20 POP. 

SUNDAY NIGHT...NEXT SHORTWAVE IN NORTHWEST FLOW TO INTERACT WITH TAIL
END OF DIFFUSE FRONT TO GENERATE CONVECTIVE COMPLEX AGAIN
IN THE PLAINS. MODELS SPAWN MESOSCALE CONVECTIVE VORTEX AND SHIFT 
THIS EASTWARD ACROSS NORTHERN MO AND WEST CENTRAL IL BY 12Z MON.
GFS APPEARS WAY OVERDONE ON QPF AND TOO FAR NORTH...THUS
FAVOR FURTHER SOUTH ETA. HAVE POPS IN ACROSS THE SOUTHERN 1/2 OF THE 
CWA WITH HIGHEST...ALBEIT STILL CHANCE POPS...IN THE FAR SOUTH.
MID CREW WILL WANT TO TAKE ANOTHER LOOK AND RE-EVALUATE THE 
POTENTIAL. LOT/S OF UNCERTAINTY WITH MESOSCALE DETAILS TO PRECLUDE
GOING ANY HIGHER ON POPS ATTIM. 

SURFACE RIDGING BUILDS IN MON AND TUE PROVIDING TRANQUIL CONDITIONS WITH
TEMPS NEAR NORMAL. BULK OF THE HEAT AND HUMIDITY WILL BE FOCUSED IN 
THE PLAINS BENEATH BUILDING UPPER LEVEL RIDGE. 

EXTENDED (WED-SAT)
NO MAJOR CHANGES. HEAT AND HUMIDITY FROM PLAINS WILL SHIFT INTO THE 
AREA BY THURS AS UPPER RIDGE SHIFTS INTO MID MISSISSIPPI VALLEY.
NEXT SYSTEM APPROACHES LATE WEEK WITH CHANCE OF SHOWERS AND 
THUNDERSTORMS. 

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

$$