[LeArc] Forecast Discussion : MLI@ 6/1/2002 3:36:58 PM

[learc@mailman.qth.net]

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


FXUS63 KDVN 012032
AFDMLI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
330 PM CDT SAT JUN 1 2002

SURFACE FRONT REMAINED ACROSS SOUTHERN IA INTO CENTRAL IL EARLY THIS 
AFTERNOON...ROUGHLY SOUTH OF I-80 THROUGH MLI THEN SE TO JUST NORTH 
OF KBMI. DEWPOINTS JUST SOUTH OF FRONT POOLED IN LOWER 70S WITH  
LAPS CAPES WELL ABOVE 3K J/KG. PLENY OF MID LEVEL CLOUDS AND PERHAPS 
FEW SPRINKLES IN ELEVATED INSTABILITY BEHIND SECONDARY COLD FRONT 
MOVING ACROSS N CENTRAL IA. FORECAST CHALLENGE CONTINUES TO BE 
THUNDERSTORM CHANCES WITH HEAVY RAIN AND SEVERE POTENTIAL TONIGHT 
THROUGH MONDAY AS FRONT LINGERS IN AREA AND WESTERN RIDGE COLLAPSES 
ALLOWING BETTER UPPER LEVEL DYNAMICS TO MOVE ACROSS AREA. 

MODELS HAVE NOT HAD GOOD HANDLE PAST SEVERAL DAYS ON POPS OR 
PLACEMENT OF QPF AND CONTINUES THIS RUN. ETA AND AVN HAD DECENT 
HANDLE ON FRONTAL BOUNDARY AT MIDDAY...SHOWING LOW OVER EASTERN WI 
AND WEAK FRONT DROPPING SOUTH. INITIAL CONCERN WILL BE AS THIS FRONT 
AND MID LEVEL SHORTWAVE CONVERGES AND INTERACTS WITH STATIONARY 
BOUNDARY ACROSS CENTRAL AND SOUTHERN IA ZONES LATE THIS AFTERNOON 
WITH POSSIBLY ENOUGH LOW LEVEL CONVERGENCE TO OVERCOME STRONG CAP IN 
PLACE. WILL PLACE SCATTERED POPS FOR EVENING IN SOUTH. BETTER 
POTENTIAL WILL BE WELL AFTER SUNSET AS H85 JET INTERACTS WITH FRONT 
WELL TO WEST AND FORMS MCS THAT WILL TRACK E-SE ALONG STATIONARY 
FRONT AND WILL GO WITH LIKELY POPS AFTER MIDNIGHT FOR ALL BUT FAR 
NORTH.

SEVERE STORMS TRAINED AND BROUGHT HEAVY RAINFALL LAST NIGHT WITH 88D 
STP AMOUNTS OF 2-3 INCHES AND WET GROUND EVIDENT ON VISIBLE IMAGERY 
FROM KEOKUK THROUGH HENRY...MONROE AND HENRY COUNTY IL. FRONT IS 
LINGERING JUST NORTH OF THIS AREA...BUT WITH ROUGHLY 1 COUNTY WIDE 
AREA SATURATED...AND NOT CONFIDENT ON WHERE BANDS WILL SET UP 
TONIGHT...WILL HOLD OFF ON ANY HYDRO WATCHES AND CONTINUE TO MONITOR 
THIS EVENING. QUICK LOOK AT 18Z META SHOWS HEAVIEST RAIN WITH MCS 
PASSING TO SOUTH OF THIS NARROW AREA OF CONCERN.  

FRONT LINGERS SUNDAY WITH H5 FLOW BECOMING MORE ZONAL AS RIDGE 
COLLAPSES. MAIN QPF AND SEVERE POTENTIAL SHIFTS A BIT NORTHWARD AS 
H85 FRONT PUSHES NORTH. WITH WEAKER CAP TO OVERCOME AND SYNOPTIC AND 
LIKELY MESOSCALE BOUNDARIES...KEPT SCATTERED POPS GOING ALL DAY. 
LIKELY POPS KEPT FOR MOST OF AREA MONDAY AND TUESDAY UNTIL LOW OUT 
WEST AND SURFACE FRONT KICKS THROUGH TUESDAY NIGHT. AVN AND UKMO 
HAVE POS TILTED H5 TROUGH MOVES THROUGH LATE WEDNEDAY NIGHT OR 
THURSDAY MORNING AND WILL KEEP SCATTERED SHOWERS IN WED PERIOD. 
BEYOND...ZONAL H5 FLOW INDICATED THROUGH SATURDAY AND WILL KEEP 
DRY. 

COORD WITH STL...THANKS.

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

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