[LeArc] Forecast Discussion : MLI@ 6/24/02 2:43:55 PM

[learc@mailman.qth.net]

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


FXUS63 KDVN 241945
AFDMLI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
245 PM CDT MON JUN 24 2002

PERSISTANCE FORECAST FOR ONE MORE NIGHT BEFORE CHANGES TAKE PLACE TO 
BRING BACK PRECIP CHANCES LATE TUESDAY INTO WEDNESDAY. UPPER RIDGE 
REMAINS FROM SE CONUS INTO MID MISSISSIPPI VALLEY. UPPER LOW 
CONTINUES TO CHURN WEST ALONG TEX/LA AREA WITH INCREASING LOW TO MID 
LEVEL MOISTURE SEEN ON 12Z UPPER ANALYSIS AND LATEST WATER VAPOR 
IMAGERY PROPAGATING INTO NORTHERN MO AND CENTRAL IL. MAIN PRECIP 
MAKER IN VICINITY CONTINUES TO BE FRONT FROM SE CO TO NW MN AT 18Z.
FORECAST CHALLENGE IS TSRA POPS AS FRONT TO WEST FINALLY PUSHES 
SOUTHEAST THROUGH CWFA TUESDAY NIGHT AND WED.

NO BIG DIFFERENCES NOTED IN SHORT TERM MODEL INTIALIZATION OR 
HANDLING OF MAJOR FEATURES. ALL HAD QPF OVERDONE OVER IL/MO THIS 
MORNING...WHERE CAP JUST BEGINNING TO BREAK THIS AFTERNOON AND MAY 
BE OVERDONE IN THAT AREA FOR TUES AS WELL WITH NO BIG CHANGES IN 
VERTICAL THERMAL PROFILES. BIGGEST DIFFERENCE IS TIMING OF FRONT 
TUESDAY NIGHT WITH AVN FASTER TUESDAY NIGHT...THEN BOTH AVN AND ETA 
SETTLING ON NW IL TO E CENTRAL IA AXIS BY 18Z WED. WILL GO ALONG 
WITH BLEND OF TWO.

STRONG CAP WILL KEEP TSRA OUT OF FORECAST AREA TO SOUTH THIS 
EVENING. GUIDANCE SHOWS SOME WEAKENING OF CAP AS GULF MOISTURE 
PUSHES INTO FAR SOUTH TUESDAY AFTERNOON AND HAVE INTRODUCED SLIGHT 
CHANCE FOR AFTERNOON PULSE STORMS. BETTER CHANCES ARRIVE TUESDAY 
NIGHT AS FRONT APPROACHES FROM NORTH AND ANTICIPATE CONVECTION THAT 
DEVELOPS ON FRONT TO BE IN WEAKENING STATE AS IT DRIFTS ACROSS 
EASTERN IA AND NW IL...WITH BEST POPS NORTH OF I-80. KEPT 40 PERCENT 
POPS BLANKETED ACROSS ENTIRE AREA ON WEDNESDAY AS SLOW MOVING FRONT 
SAGS ACROSS AREA. THURSDAY AND BEYOND...UPPER RIDGE TO WEST 
CONTINUES TO BUILD AND PRODUCES WEAK NW FLOW INTO FORECAST AREA FOR 
DRY AND CONTINUED WARM WEATHER FRIDAY AND SAT. SOME DISAGREEMENT IN 
GUIDANCE WITH MRF TRYING TO BRING WEAK UPPER SHORTWAVE THROUGH RIDGE 
LATE SAT INTO SUNDAY...WHICH IS NOT SUPPPORTED BY UK OR ECMWF AND 
WILL KEEP DRY WITH TEMPS CLOSE TO GUIDANCE.
 
IA...NONE.
IL...NONE.
MO...NONE.

DLS