[LeArc] Forecast Discussion : MLI@ 5/15/2003 2:04:58 PM

[learc@mailman.qth.net]

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


FXUS63 KDVN 151902
AFDMLI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
155 PM CDT THU MAY 15 2003

.OVERVIEW...UPPER LOW MOVING EAST WITH REGION UNDER NORTHEAST LAKE
EFFECT WITH LOTS OF CLOUDS KEEPING TEMPERATURES COOL.  DIURNAL
HEATING ALSO SUPPLYING ENERGY FOR CUMULUS CLOUDS WITH SLIGHT CHANCE
OF SOME VERY LIGHT SHOWERS FAR NORTH SECTIONS LATE TODAY.  LARGE SCALE
FEATURES SHOW SURFACE AND UPPER LEVEL RIDGING WITH NORTHEAST TO
NORTH FLOW TO CONTINUE ALLOWING FOR SOME CLEARING NEXT 12-24 HOURS.
SOUTHWEST SYSTEM SUGGESTED TO PASS SOUTH AREA PER HEIGHT FALLS AND
JET ORIENTATION OVERLAYED WITH THERMAL FIELDS.  UPPER FLOW INDICATIONS
SUGGEST JET MOVING NORTH AS IT SHOULD AS MOVE INTO MID TO LATE SPRING.

...CLEARING TREND AND TEMPERATURES NEAR TERM ISSUE WITH NEXT SYSTEM
NEXT WEEK LONGER TERM CHALLENGE...

.DIAGNOSIS (DAYS 1-3)...LOW LEVEL MOISTURE TO SLOWLY EBB SOUTHEAST
TONIGHT PER NOWCAST TOOLS...ALSO SUGGESTED BY MOST MODELS.  WILL USE
PERSISTENCE WHICH SUGGEST LOTS OF FAIR WEATHER CUMULUS BY MID DAY
TOMORROW WITH HIGH CLOUDS...MAINLY ALONG AND SOUTH OF HIGHWAY 34. SLIGHT
CHANCE OF SOME WEAK SHOWERS OR SPRINKLES MID PM WITH LAKE ENHANCED
CONVERGENCE ZONE ALONG AND EAST OF MISSISSIPPI RIVER BUT LEAVE FOR NIGHT
SHIFT TO LOOK CLOSER AT.  LOWS WILL GO ON LOW SIDE WHERE WE CLEAR OUT
AND NEAR TO ABOVE SOUTHEAST WHERE MORE CLOUDS LIKELY TO HANG ON DESPITE
OVERALL DOWNWARD MOTION...DUE TO FLOW OFF LAKE MICHIGAN.  SOUTHWEST
SYSTEM...ALL SUGGESTIONS TO GO SOUTH EXCEPT FOR SOME HIGH CLOUDS. GFS-
AVN QPF FIELDS NOT REASONABLE AND OUT OF PLACE WITH OVERALL FORCING...SO
FAIRLY CERTAIN QPF NOT TO HAPPEN...KEEP THINGS DRY AS STAY UNDER SURFACE
HIGH NORTH OF GREAT LAKES WHICH WE SEE A LOT OF CLIMATOGICALLY THIS TIME
OF YEAR.  PUTS AREA IN QUIET AND SEASONABLY NICE EAST TO NORTHEAST FLOW
THROUGH SUNDAY WITH SLOWLY MODERATING TEMPERATURES...LOWS NEAR TO
SLIGHTLY BELOW SATURDAY AND HIGHS NEAR BLEND INTO SUNDAY.

EXTENDED (MON-THU)...ALL SOLUTIONS SUPPORT MODERATE TO STRONG COLD FRONT
LATE MONDAY AND EARLY TUESDAY...GO LIKELY POPS LATE MONDAY AND CHANCE
EARLY TUESDAY WITH DECENT TO EXTENSIVE SQUALL LINE PROBABLE.
TEMPERATURES...GO AT LEAST 2 CATEGORIES ABOVE GUIDANCE MONDAY AHEAD OF
FRONT AND THIS LIKELY TOO LOW AS EXPECT TEMPERATURES TO PUSH UPPER 80S
INTO LOWER 90S...MEX HAS "ONLY 77"...GET REAL!  THEN...GOOD COOL DOWN
WITH TEMPERATURES ON COOL SIDE OF MEX AFTER FRONT...POSSIBLY WINDY NW
WINDS.  BETTER HANDLE BY TOMORROW PM ALONG WITH HOW WIDESPREAD SEVERE
THREAT LATE MONDAY INTO TUESDAY. LOTS OF ENERGY WITH SYSTEM...ONLY
QUESTION IS PHASING AND TIMING.

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

$$

NICHOLS