[LeArc] Forecast Discussion : MLI@ 12/10/02 2:45:45 AM

[Richard R. Sample]

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


FXUS63 KDVN 100859
AFDMLI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
250 AM CST TUE DEC 10 2002

CONCERNS IN NEAR TERM INCLUDE TEMPS...AND POTENTIAL FOR STRATUS AND
FOG NEXT FEW NIGHTS...THEN PCPN CHCS/TYPE LATE WEEK WITH 
UPPER TROUGH.

SHORT TERM TRANQUIL WITH SURFACE HIGH WELL EAST INTO THE OHIO VALLEY AND
LIGHT LLVL S/SE WIND. TROUGH LIES IN PLAINS WITH 11-3.9 MICRON 
SATELLITE AND OBS REVEALING STRATUS AND FOG WITH LLVL MOISTURE POOLING
AHEAD OF TROUGH INTO NORTHERN KS AND SOUTHEAST NE...NOT WIDESPREAD AS FORCING 
NOT SUPPORTIVE. FOR TODAY...WILL SEE LOTS OF SUNSHINE WITH 
SOME PASSING CIRRUS. BOUNDARY LAYER GRADUALLY MOISTENING THUS SHOULD SEE LITTLE
BIT SMALLER DIURNAL SWING BUT STILL NEAR 25 TO 27 DEGS OR SO. 
TRAJECTORIES SUGGEST EASTERN KS SOURCE REGION FOR SOUTHERN IA TODAY...WHERE
READINGS YESTERDAY TOPPED OUT INTO THE UPPER 40S...SO OVERALL THIS
SUPPORTS FORECAST AND TREND OF GOING AT OR JUST ABOVE WARMEST MET GUIDANCE.

TONIGHT...UPPER LEVEL LOW PASSES TO OUR SOUTH. MODEL TSECTS AND RELH PROGS
SUGGEST SOME INCREASE IN CIRRUS OVER S/E SECTIONS. 
MEANWHILE...SURFACE TROUGH IN PLAINS IN NEARLY SAME LOCATION SO NOT QUITE
SOLD ON LOW CLOUDS. FORCING SUPPORTIVE OF POCKETS OF ST/FG 
MAINLY JUST WEST OF CWA INTO WESTERN AND CENTRAL IA...BUT CLOSE PROXIMITY
SO OVERALL TO HANDLE CIRRUS S/E AND POTENTIAL FOR SOME LOW CLOUDS
WEST WILL BROADBRUSH BECOMING PC IN ZONES. DAY CREW CAN RE-EVALUATE BASED
ON TRENDS. UNFORTUNATELY CLOUDS WILL HAVE IMPACT ON LOWS TONIGHT.
IF LOW CLOUDS FAIL TO MATERIALIZE THEN WESTERN SECTION LIKELY COLDEST WITH
HIGH CLOUDS KEEPING TEMPS A BIT WARMER EAST. MODEL BLEND FAIRLY CLOSE
ON MINS WHICH SEEMS BEST ROUTE TO TAKE AT THIS POINT. 

WED NIGHT-THU MODEL TSECTS AND RELH PROGS INDICATE THIS IS PERIOD WHERE
LLVL MOISTURE WILL INCREASE GREATLY...PRODUCING EXTENSIVE
STRATUS DECK WITH AREAS OF FOG AND EVEN DRIZZLE WITH DRY MID LEVELS AND
LACK OF FORCING. WILL REMOVE POPS ON THU...OTHERWISE TEMPS LOOK GOOD 
ALREADY ACCOUNTING FOR CLOUDS. WILL MAINTAIN CHC POPS THU NIGHT-FRI WITH
BETTER POTENTIAL FOR MEASURABLE PCPN WITH INCREASE IN FORCING.
THERMAL TEMP PROFILE SUPPORTIVE MAINLY OF RAIN THOUGH CAN/T RULE OUT SOME
WET FLAKES ESP NORTH/WEST LATE FRI WITH PASSAGE OF SURFACE TROUGH.
MODELS STILL OFFERING WIDE ARRAY OF SOLUTIONS WITH SYSTEM...WITH GFS/AVN
DEEPEST AND SLOWER AND ODD MAN OUT WITH REGARD TO ENSEMBLE SOLUTIONS.
IF GFS/AVN WERE TO VERIFY THEN FRI NIGHT-EARLY SAT WOULD BE BEST SHOT AT
MEASURABLE PCPN WITH CONFLUENT LLVL FLOW. UKMET MORE PROGRESSIVE
AND SHOWS LLVL RIDGING ON SAT. GIVEN UNCERTAINTIES WILL LEAVE EXTENDED
ALONE. DID BUMP UP MINS THU NIGHT WITH TROUGH STILL WEST OF THE REGION AND
CLOUDS AND LLVL SOUTHWEST WINDS. 

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


M^2