[LeArc] Forecast Discussion : MLI@ 9/2/02 2:19:38 AM

[learc@mailman.qth.net]

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


FXUS63 KDVN 020725
AFDMLI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
223 AM CDT MON SEP 2 2002

MAIN CONCERN THIS ISSUANCE WILL BE IMPACTS OF STRONG MID LEVEL SYSTEM
AND ASSOCIATED COLD FRONT MOVING THROUGH REGION LATE THIS AFTERNOON AND
TONIGHT.

02/00Z H5 ANALYSIS SHOWED POTENT S/W  FROM WESTERN SASKATCHEWAN
INTO WESTERN MONTANA WITH 60M HGT FALLS NOTED OVER NE MONTANA.  ANOTHER
WEAK IMPULSE MOVING THROUGH CENTRAL MN WAS GENERATING WIDESPREAD TSRA
FROM EASTERN MN INTO WI.  TAIL END OF THIS SYSTEM ALSO AIDING ISOLATED
TSRA OVER NORTHERN MOST COUNTIES OF CWA.  AT THE SURFACE REGION WAS
DOMIATED BY BROAD SE FLOW.  LOW PRESSURE ASSOCIATED WITH SASK/MT
SYSTEM WAS OVER NCNTRL SD WITH COLD FRONT EXTENDING W INTO WY.  THERE
ALSO APPEARS TO BE A WEAK WARM FRONT EXTENDING E INTO MN.

MODELS SEEM TO HAVE INITIALIZED OK THIS RUN.  ALTHOUGH AVN HAS BETTER
HANDLE ON VORT MOVING THROUGH NRN MT.  MODELS ABOUT THE SAME HANDLING
MOVEMENT OF COLD FRONT THROUGH REGION TODAY/TONIGHT.  ALTHOUGH AVN
FAVORING A LITTLE FASTER MOVEMENT OF THE FRONT THROUGH THE UPPER
MISSISSIPPI VALLEY THIS AFTERNOON AND THIS EVENING.

LABOR DAY FOR MUCH OF THE CWA WILL FEATURE 4TH OF JULY LIKE TEMPS.
SOUTH TO SOUTHWESTERLY FLOW AHEAD OF APPROACHING FRONT SHOULD ALLOW GOOD
MIXING THIS AFTERNOON.  850 TEMPS AROUND 20 LEND SUPPORT TO HIGHS AROUND
90 PER MAV/FWC MOS. ON GOING TSRA BETWEEN KALO AND KDBQ IS EXPECTED TO
DISSIPATE AS FORCING WEAKENS AND RE-FOCUSES TO OUR WEST THIS MORNING.
MAIN TSRA THREAT FOR CWA WILL BE FROM LATE AFTERNOON THROUGH THE
EVENING HOURS JUST AHEAD OF THE APPROACHING FRONT.  PER SPC DAY1
DISCUSSION CONVECTIVE INITIATION ACROSS SOUTHERN PORTIONS OF CWA WILL
BE SOMEWHAT INHIBITED BY WARM MID LEVELS TEMPS NEAR THE FRONT.  CAN'T
RULE OUT TSRA COMPLETELY WITH STRENGTH OF SYSTEM...SO WILL GO WITH LOW
CHANCE POPS.  NORTHERN CWA WILL BE UNDER THE INFLUENCE OF STRONGER MID
LEVEL DYNAMICS WHICH SHOULD BE ABLE TO OVERCOME CAP AND WILL GO WITH
50 POPS LATE AFTERNOON/EVENING.  WILL ALSO MENTION SEVERE
POSSIBILITY WITH MODERATE INSTABILITY AND STRONG LOW LEVEL SHEAR...
ESPECIALLY DURING THE LATE AFTERNOON.  LOOKS LIKE PCPN THREAT WILL BE
OVER FOR MUCH OF CWA BY EARLY TUESDAY MORNING AS FRONT PUSHES WELL
SOUTH.  HIGH PRESSURE SETTLES IN WITH A DRIER AND SOMEWHAT COOLER
AIRMASS FOR MID WEEK.

NO CHANGES PLANNED FOR THE EXTENDED AT THIS TIME.  HOWEVER...NEW
MRF/UKMET ARE POINTING TOWARD WARMER TEMPS WITH UPPER RIDGE
BUILDING IN AGAIN AND ANOTHER FRONT APPROACHING REGION BY LATE WEEK.


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

DLF