[LeArc] Forecast Discussion : MLI@ 8/10/02 2:14:10 AM

[learc@mailman.qth.net]

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


FXUS63 KDVN 100711
AFDMLI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
205 AM CDT SAT AUG 10 2002

IMPRESSIVE CLOSED UPPER LOW SPINNING OVER NORTHERN PLAINS WITH CIRCULATION
CENTER LOCATED JUST NORTH OF MINOT ND. MODELS SHOW SYSTEM 
OPENING UP JUST A BIT WHILE LIFTING NORTHEAST INTO ONTARIO NEXT 36 HRS
AND ANALYSIS SUPPORTS THIS WITH JET ENERGY ON EAST SIDE OF CIRCULATION. 
AT SURFACE...WEAK FRONTAL ZONE DRAPED FROM WESTERN MN SOUTHWARD
THROUGH EASTERN NE AT 06Z WITH FAIRLY NARROW BAND OF CONVECTION MOVING
QUICKLY EASTWARD THROUGH MN AND NORTHWEST IA WITH AID OF PVA...AND
UPPER DIVERGENCE ASSOCIATED WITH LFQ OF JET.

MANY CONCERNS THIS FORECAST CYCLE. NEAR TERM CONCERNS ARE WITH MAX TEMPS
TODAY AND PCPN CHCS WITH WEAK FRONTAL ZONE...THEN TEMPS...PCPN CHCS 
AND POTENTIAL FOR HEAVY RAIN AND POSSIBLY SOME SEVERE WX LATE SUN/SUN NIGHT
WITH FRONT LIFTING BACK NORTH. SAME CONCERNS AGAIN MON THROUGH EARLY TUE
WITH STRONG COLD FRONT AND UPPER TROUGH. 

MODELS IN DECENT AGREEMENT ON MASS FIELDS NEXT 48 HOURS...WITH SOME
DIFFERENCES IN QPF. FOR TODAY...WEAK FRONTAL ZONE APPROACHES
BUT BECOMES DIFFUSE AS FLOW SURFACE TO H85 BECOMES INCREASINGLY WESTERLY.
BEST FORCING TO SHIFT FROM MN AND NORTHERN IA INTO WI DURING DAYTIME
WITH GLANCING BLOW TO CWA...ESPECIALLY NORTHERN ZONES. ALL OF THIS COUPLED 
WITH LIMITED MOISTURE SUGGESTS LOW CHC PCPN AND MAINLY ACROSS NORTHERN
SECTIONS ON TAIL END OF DYNAMICS. NEXT CONCERN IS MAX TEMPS...AS POTENTIAL
FOR BUST. NGM SFC PARCEL TRAJECTORIES SUGGEST SOURCE REGION OVER SOUTHERN
IA FROM NORTHEAST KS...WHERE READINGS ON FRIDAY TOPPED OUT IN THE U80S.
ETA 2M TEMPS CONTINUE WAY OVERDONE...DEPICTING 95 DEGS IN FAR SOUTHWEST ZONES.
HAD TO GO DOWN INTO OKLAHOMA BEFORE SEEING READINGS THIS HOT ON FRI!
LACK OF STRONG LLVL FLOW SAYS NO WAY JOSE. SO...WITH FILTERED SUNSHINE AND
SOUTHWEST SFC WINDS WILL SIDE TOWARD BLEND OF MAV/FWC GUIDANCE.

FRONTAL ZONE TO STALL SOUTH OF AREA ON SUN WITH RIDGING SHIFTING QUICKLY ACROSS
AREA DURING 1ST HALF OF DAY. H85 TEMPS FEW DEGS WARMER AND WITH
AMPLE SUNSHINE...EXPECT READING SIMILAR TO TODAY...IF NOT A FEW DEGS WARMER.
CONCERN THEN SHIFTS TO PCPN CHCS IN AFTERNOON. FRONTAL ZONE STALLED
JUST SOUTH OF CWA BEGINS TO EDGE NORTHWARD AND WITH AMPLE HEATING CAN/T RULE
OUT FEW STORMS DEVELOPING IN THE SOUTH. SUNDAY NIGHT...LOW LEVEL JET AND
MOISTURE TRANSPORT STRENGTHEN AND WITH FRONTAL ZONE LIFTING NORTH
EXPECT BETTER COVERAGE OF CONVECTION...THOUGH DISCREPANCIES WITH TIMING 
OF FRONT SO WILL HAVE TO SIDE WITH HIGH CHC POPS AND LET NEXT SHIFT RE-EVALUATE.
SUSPECT LIKELY POPS WILL BE NEEDED BUT DIFFICULT TO PINPOINT LOCATION GIVEN
TIMING ISSUES. GIVEN STRENGTH OF MOISTURE TRANSPORT...SOME 
LOCALLY HEAVY RAINS POSSIBLE. SEVERE THREAT AS WELL AND MAINLY HAIL.

STRONG COLD FRONT PROGGED TO SHIFT ACROSS REGION MONDAY NIGHT AND EARLY TUE.
PCPN ON MON WILL FOCUS ON TWO TIME PERIODS...MORNING WITH FRONT
LIFTING THROUGH...THEN AGAIN LATE IN THE DAY AHEAD OF APPROACHING COLD FRONT. 
LOTS OF MOISTURE AND STRONG DYNAMICS FAVORABLE FOR SOME HEAVY RAIN.
LIKELY POPS REASONABLE. TEMPS VERY DIFFICULT ON MON AS FORECAST MAY BE A BIT
OPTIMISTIC GIVEN CLOUDS AND PCPN.


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