[LeArc] Forecast Discussion : MLI@ 5/25/02 3:18:20 AM

[learc@mailman.qth.net]

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


FXUS63 KDVN 250818
AFDMLI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
315 AM CDT SAT MAY 25 2002

SURFACE LOW AT 07Z OVER N CENTRAL MO WITH COLD FRONT TRAILING SW AND 
STATIONARY FRONT EAST ACROSS CENTRAL IL. MCS TRACKING AHEAD OF LOW 
SHOWING WARMING TOPS PAST COUPLE HOURS. WIDESPREAD LIGHT RAIN 
OCCURING AHEAD OF INVERTED TROF OVER CENTRAL AND EASTERN IA. SURFACE 
DEWPOINTS IN 30S ADVECTED INTO NORTHERN ZONES BY NE WINDS EATING 
AWAY AT MUCH OF STRATIFORM RAIN IN NORTH EARLY THIS MORNING...WHILE 
FAR SOUTHERN ZONES WILL BE IN HEAVIEST RAINFALL OF DECAYING SYSTEM 
AT FORECAST ISSUANCE. AFTER HANDLING ENDING OF RAIN THIS MORNING... 
MAIN FORECAST CHALLENGE IS DEGREE OF LINGERING CLOUD COVER TODAY AND 
IMPACTS ON TEMPERATURES.

TIMING DIFFERENCES CONTINUE WITH H5 SHORTWAVE AND SURFACE LOW 
TRACKING INTO SOUTHERN LOWER MI BY AFTERNOON. AVN CONTINUES MOST 
PROGRESSIVE WITH ETA AND UKMET A BIT SLOWER. WILL FOLLOW COMPROMISE 
SOLUTION WITH MAIN VORT MOVING FROM NEAR OMA TO SE WI BY 18Z. MODELS 
HAVE QPF BULLSEYE CENTERED TOO FAR INTO DRY LOW LEVEL AIRMASS AND 
ANTICIPATE HIGHEST AMOUNTS UP TO .75 INCHES OVER SE IA AND IL ZONES 
S OF I-80...BELOW FFG VALUES...BUT WILL NEED TO BE WATCHED. NOWCAST 
TOOLS TIME CENTER OF MCS INTO N CENTRAL IL BY 5 AM...WHICH WOULD 
PLACE STRATIFORM REGION OVER CWFA WITH FEW LIGHTNING STRIKES STILL 
POSSIBLE UNDER COLDEST CLOUD TOPS AND WILL INCLUDE ISOLATED EARLY 
MORNING THUNDER OVER IL ZONES. CURRENT FORECAST OF CATEGORICAL 
LIGHT RAIN FOR MORNING LOOKS GOOD FOR IA AND MO ZONES...BUT WILL 
EXTEND MAINLY SPRINKLES INTO EARLY AFTERNOON FOR N CENTRAL IL ZONES.
 
00Z META FORECAST SOUNDINGS SHOW MOIST LAYER BELOW H85 LINGERING 
WELL INTO AFTERNOON WITH ONLY WEAK COLD ADVECTION AT H85 BEHIND LOW 
OVER GREAT LAKES AND DO NOT ANTICIPATE SIGNIFICANT CLEARING UNTIL 
LATE AFTERNOON. WITH THE CLOUD COVER...COMBINED WITH ONLY LIGHT NW 
SURFACE WIND AND WET GROUND...WILL UNDERCUT A FEW DEGREES BELOW 
COOLER FWC.

WARM UP FOR SUNDAY STILL LOOKS GOOD AS RETURN FLOW DEVELOPS RAPIDLY 
IN RESONSE TO NEXT H5 WAVE MOVING INTO ROCKIES. ETA AND NGM MORE 
AGRESSIVE WITH POPS ACROSS NORTH SUNDAY NIGHT WITH NORTHERN STREAM 
WAVE PASSING TO NORTH...WITH AVN KEEPING BULK OF PRECIP TO WELL TO 
NORTH. GOING 30 PERCENT FOR NORTHERN IA ZONES LOOKS GOOD AND HAVE 
INTRODUCED SLIGHT POPS FOR MONDAY AFTERNOON WITH H85 THETA E RIDGE 
PUSHING INTO CENTRAL IA. 

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

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