[LeArc] Forecast Discussion : MLI@ 4/4/2003 4:39:02 AM

[learc@mailman.qth.net]

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


FXUS63 KDVN 041035
AFDMLI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
434 AM CST FRI APR 4 2003

WEAK LOW NORTHEAST OF KBRL WITH FRONT EXTENDING EAST TO KIKK. NEXT
SYSTEM MOVING NORTHEAST FROM PLAINS. LIKE THE 06Z RUC DEPICTING
PRECIP THROUGH FORCING FIELDS...NOT QPF FIELDS. OMEGA FIELDS
INDICATE THAT PRECIP BREAKING OUT OVER THE WESTERN HALF AROUND 12Z...
AND CURRENT RADAR TRENDS INDICATE THIS TO BE ON TRACK. PRECIP THEN
BREAKS OUT ACROSS REMAINDER OF CWFA BY LATE MORNING. CAA TO
CONTINUE DURING THE DAY WITH TEMPERATURES STEADY OR SLOWLY FALLING
MOST AREAS. CONVECTIVE PRECIP TO REMAIN ROUGHLY SOUTH OF A KFFL TO
KSQI LINE. PARTIAL THICKNESS FIELDS INDICATE PRECIP TO MIX AND
LIKELY CHANGE OVER TO SNOW DURING THE AFTERNOON OVER ABOUT THE
NORTHWEST HALF OF CWFA. PER OMEGA FIELDS PRECIP TO LINGER INTO THE
EVENING HOURS BEFORE ENDING.

QUIET WX THEN FOR SATURDAY/SATURDAY NIGHT AS HIGH PRESSURE MOVES
THROUGH. SHOULD BE CLOUDY MOST OF THIS TIME WITH A BRIEF BREAK IN
CLOUDS DURING THE DAY SATURDAY.

ATTENTION THEN TURNS TO NEXT MAJOR SYSTEM FOR LATE IN THE
WEEKEND/EARLY NEXT WEEK. UKMET PAINTS AN OMINOUS PICTURE AND ECMWF
IS IN FAIR AGREEMENT AS WELL WITH 00Z AVN COMING IN LINE AS WELL.
NEGATIVELY TILTED SYSTEM TO COME OUT OF THE ROCKIES WITH ANOTHER
NEGATIVE SYSTEM MOVING ONTO THE WEST COAST. THERE SHOULD BE AN
INTERACTION BETWEEN THE TWO SYSTEMS (ALA FUJIWARA) TO SPIN UP THE
FIRST SYSTEM. NET RESULT IS CWFA IS IN A DEEP COLD CONVEYOR BELT WITH
COLD SURFACE TEMPERATURES ALREADY IN PLACE. UKMET INDICATES SURFACE
LOW TO OCCLUDE IN SOUTHERN KANSAS AND MOVE TOWARD KSTL WHILE A NEW
LOW DEVELOPS IN THE LOWER OHIO VALLEY. MODELS SHUNT MOST OF THE
PRECIP TO THE SOUTH...HOWEVER THE COLD CONVEYOR BELT IS OF SUCH SIZE
AND STRENGTH THAT THIS IS NOT CONCEPTUALLY SOUND. MORE MOISTURE
SHOULD WRAP UP AROUND ON THE COLD CONVEYOR BELT AND INTO THE CWFA.

THE QUESTION THEN IS NOT IF IT WILL SNOW...BUT HOW MUCH. MODELS
CURRENTLY SHOW NOT MUCH SNOW...BUT ARE PLAYING CATCH UP AND WILL
LIKELY DO THIS FOR ANOTHER 2-3 MODEL RUNS. POTENTIAL IS THERE FOR
SIGNIFICANT SNOW WITH H7 AND H5 LOWS PASSING THROUGH THE CWFA AND H85
LOW TO THE SOUTH AND EAST. CONCEPTUAL MODELS MODELS INDICATE
SIGNIFICANT FORCING AND MOISTURE WILL BE IN PLACE ACROSS THE CWFA
STARTING SUNDAY AFTERNOON AND CONTINUING INTO MONDAY MORNING. THESE
CONCERNS TO BE PASSED ON TO THE DAY SHIFT WITH HEADLINES LIKELY TO BE
ISSUED EITHER LATER TODAY OR SATURDAY MORNING. ADVISORY CRITERIA WILL
EASILY BE MET...BUT COMBINATION OF SNOW AND WIND ARGUES THAT A WATCH
WOULD BE MORE APPROPRIATE.

REMAINDER OF EXTENDED (TUE TO THU) HAS NOT BEEN CHANGED. HOWEVER IF
SIGNIFICANT SNOW AMOUNTS OCCUR SUN/MON...TEMPS FOR TUESDAY ON WOULD
NEED TO BE LOWERED.

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

$$

SF