[LeArc] Forecast Discussion : MLI@ 10/29/02 1:42:58 PM

[learc@mailman.qth.net]

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


FXUS63 KDVN 291952 AAA
AFDMLI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
150 PM CST TUE OCT 29 2002

OPERATIONAL MODEL RUNS NOT BACKING UP CONCEPTUAL THINKING OF THE LAST SEVERAL
DAYS...AND SUGGEST BASICALLY NIL EVENT FOR REGION WED-THU WITH
GUIDANCE POPS AROUND 20% MOST LOCATIONS. EXPECTED TO SEE PRONOUNCED SURFACE
WAVE DEVELOP ALONG BAROCLINIC ZONE IN SOUTHERN PLAINS 
LIFT E/NE THROUGH MID MISSISSIPPI VALLEY WED-THU. SURFACE WAVE ATTIM IN
SOUTHEAST CO...BUT MODELS WEAKEN IT AS IT TRANSLATES E/SE THROUGH
OK/TX PANHANDLES. NEG TILT UPPER WAVE LIFTING OUT OF ROCKIES INTO THE PLAINS
TO SHEAR EASTWARD AS IT ENCOUNTERS CONFLUENT UPPER FLOW.
SO...EXPECT LOTS OF PCPN IN THE PLAINS WITH STRONG UPPER FORCING AND UPSLOPE
WITH PCPN SHIELD SHIFTING EAST AND WEAKENING WITH TIME. OMEGA FIELDS 
ARE WIMPY. SO...WITH ALL THIS BEING SAID...WILL BE TONING FORECAST DOWN EVEN
MORE FROM PREVIOUS SHIFT. SENT UPDATE HWO INCORPORATING THESE THOUGHTS.
BACK TO THE NEAR TERM...SHORTWAVE AND ASSOCIATED SURFACE LOW PASSING SOUTH AND
EXPECT TO SEE PCPN DIMINISH INTO EVE...WITH SOME LINGERING DZ INTO THE
EARLY OVERNIGHT. CLOUDS BREAKING UP ATTIM OVER GREAT LAKES ALLOWING SOME 
SUNSHINE. MODELS LATCH ONTO THIS DRYING IN THE H925-H85 LAYER AND ROTATE 
IT SOUTH FROM WI INTO REGION...SO CAN/T RULE OUT SOME BREAKS LATER TONIGHT NORTH
AND CENTRAL...AND OVER ENTIRE AREA ON WED. THIS MAKES TEMP FORECAST
A BIT TRICKY. WITH POTENTIAL FOR BREAKS IN THE CLOUDS...WILL LEAN TOWARD THE
COOLER END OF GUIDANCE NORTH TONIGHT WITH BLEND ELSEWHERE. 
WILL BE OPTIMISTIC AND GO WITH BECOMING P/SUNNY ON WED. THEREFORE...WILL GO 
A CAT OR SO WARMER THAN TODAY...WHICH IS CLOSE WITH BLEND OF FWC/MAV GUIDANCE.
WED NIGHT...SHEARED WAVE APPROACHES AND DESPITE WEAKENING WHICH MAY BE
STILL BIT OVERDONE BY MODELS...WILL GO WITH CHC POPS -SN. 
REAL BLAST OF COLD AIR TO ARRIVE LATE THU-FRI AS PIECE OF ENERGY FROM HUDSON
BAY POLAR VORTEX DIVES SOUTH. WILL KEEP MENTION OF FLURRIES.

EXTENDED (SAT-TUE)...
NO BIG CHANGES. UPPER TROUGH SHIFTS EAST WITH HEIGHTS RISING LEADING TO
GRADUAL WARMUP. DIFFERENCES ON TIMING WITH NEXT SYSTEM. 
UKMET REMAINS QUICKEST AND SUGGESTS SMALL THREAT PCPN LATE SUN-EARLY MON AND
AGAIN LATE TUE WITH FAST MOVING SYSTEMS. FOR NOW...WILL KEEP MENTION 
TO EARLY NEXT WEEK.  
 
 
.DVN...
IA...NONE.
IL...NONE.
MO...NONE.