[LeArc] Forecast Discussion : MLI@ 10/2/02 2:17:04 AM

[learc@mailman.qth.net]

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


FXUS63 KDVN 020717
AFDMLI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
215 AM CDT WED OCT 2 2002

.OVERVIEW...HEAVY RAIN EVENT IS WELL UNDERWAY.  SLOW MOVING BOUNDARY
PRODUCING TRAINING OF SHOWERS AND STORMS WITH AREAS ALONG AND NORTH OF
INTERSTATE 80 RECEIVING 1 TO 2.5 INCHES PAST 12 HOURS.  RADARS VERY
OMINOUS WITH NEARLY CONTINUOUS BANDS OF SHOWERS AND STORMS STRETCHING
FROM NORTHERN ILLINOIS BACK TO WESTERN KANSAS.  UPPER AIR ANALYSIS
SHOWS STRONG SW FLOW WITH SMALL PERTURBATIONS WITH LITTLE MOVEMENT.
SURFACE ANALYSIS SHOWS WEAK WAVE EXTREME NW MISSOURI AND EAST WEST
BOUNDARY FROM SOUTH OF CHICAGO TO WEAK LOW.  ALL IN ALL A TEXTBOOK
EXTENDED MODERATE TO HEAVY RAIN EVENT FOR AREA.

...HEAVY RAIN AND FLOODING POTENTIAL NEAR TERM ISSUE INTO THURSDAY AND
THEN MORE HEAVY RAINS LATE THURSDAY INTO FRIDAY WITH WESTERN TROUGH AND
REMAINS AND/OR MOISTURE FROM HURRICANE LILI LONGER RANGE ISSUE...

.DIAGNOSIS AND DAYS 1-3...MODEL QPF HANDLING SYSTEM POORLY WITH NGM/AVN
SLIGHTLY BEST.  THEY DO HANDLE OVERALL FORCING WELL WHICH SUPPORTS
SHOWERS AND STORMS WITH LOCALLY HEAVY RAINS INTO MORNING ALONG AND
NORTH OF INTERSTATE 80 GRADUALLY MOVING INTO SOUTHERN SECTIONS OF
FORECAST AREA BY PM.  HEAVY RAIN WORDING NEEDED WITH LARGE AREAS OF
ADDITIONAL .5 TO 2" AMOUNTS LIKELY.  RECENT DRY PERIOD ONLY REASON NOT
GOING WITH FLOOD WATCH AND WILL MONITOR NEXT FEW HOURS BUT RIGHT PLAN
FOR ESF.  LIKELY TO CATEGORICAL POPS TONIGHT SOUTH SECTIONS WITH LOWER
POPS NORTH AS FRONT SAGS SOUTH.  THEN INCREASING POPS WITH WARM FRONT
THURSDAY AND THURSDAY NIGHT.  MAJOR WAVE WITH INTENSE TRIGGER SUPPORT
LOTS OF SHOWERS AND SOME STORMS WITH HEAVY RAINS A NEAR CERTAINTY.
WILL MAKE NORMAL ADJUSTMENTS FOR CLOUDS AND PRECIPITATION.

.EXTENDED...(SAT-TUE)...ALL INDICATIONS OF A COOLER PERIOD WITH NW
FLOW.  CHANCE OF RAIN SUNDAY WITH NEXT SHORT WAVE.  PLAN ON MINOR
CHANGES AS NEEDED.  GOOD CHANCE OF KILLING FROST AND FREEZE NEXT WEEK.

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

NICHOLS