Flash Flood in Missouri, August 20, 2002

AREA FORECAST DISCUSSION...CORRECTED HEADLINE BLOCK
NATIONAL WEATHER SERVICE ST LOUIS MO
400 AM CDT TUE AUG 20 2002

FCST PROB FOR THE MRNG PACKAGE IS PCPN CHCS AND THEIR EFFECT ON
TEMPS TDA.

00Z MODELS CLUELESS IN THE NR-TERM ON LRG COMPLEX OF TSTMS ROLLING
ACRS MO AND PRTNS OF SRN IL ATTM.  THIS COMPLEX SEEMS TO BE THE
RESULT OF LOW-MID LVL FRONTOGEN IN STILL RATHER MOIST AND ELEVATED
UNSTABLE AMS.  STMS WERE MOST EFFICIENT OVR SRN MO WHERE HIGHEST
PWATS WERE FOUND NR SFC FNT.  OVERALL MODELS ARE IN AGRMT ON UPR LVL
RDG BLDG ACRS MO/IL THE NXT 24-36HRS AND THEN PREVAILING INTO LATE
WK.  ON SFC FEATURES...PREFER AVN/NGM HANDLING OF FNTL POSN
TDA...WHERE MID-LVL HI PRES WL KP FNT FM SAGGING MUCH MORE TO THE
S.  FNT XPCTD TO GO FM W-E ORIENTED ACRS SRN MO TO MORE NW-SE
ORIENTED ACRS SRN/WRN SXNS OF FA LATE TDA...AND THEN RIDE THRU FA AS
WRMFNT TNGT.

FOR TDA...PLAN TO GO AOA HIGHER FWC POPS.  FRONTOGEN FORCING XPCTD
TO CONT TO SAG SWD INTO SRN/WRN PRTNS OF FA...AND WITH MOIST/INSTAB
AXIS XPCTD TO PERSIST ACRS SRN/WRN SXNS OF FA ALSO TDA...XPCT
CURRENT COMPLEX ACRS FA TO SAG INTO THESE AREAS...SO WL GO HI POPS
THERE.  OTR PROBLEM IS NEW CONVECTION FIRING FURTHER NWWD AND JUST
AHD OF MCS IN NEB/SWRN IA.  MN FLO WL WANT TO PUSH THIS AREA EWD
INTO NRN FA...SO PLAN ON GOING HI POPS THERE AS WELL.  RMNDR OF FA
(STL AREA AND SWRN IL) WL SEE CHC POPS THIS MRNG AS PCPN BCMS MAINLY
STRATIFORM IN NATURE.  C-VECS AND MN FLO WL WANT TO PUSH MCS IN ERN
NEB/SWRN IA ESEWD...WHILE BEST FORCING SHOVES OFF TO THE N.  THIS
COMPLEX MAY AFFECT AN ALREADY SATURATED MID-MO DURG LTR MRNG
HRS/MIDDAY...BUT LIKELY IT WILL TAKE A MORE NLY ROUTE TWDS NRN FA.
DON/T XPCT MUCH IN REDVLPMT DURG AFTN HRS AFT THINGS SETTLE DOWN
SOMEWHAT...BUT MOST LIKELY AREA TO SEE IT WL BE SRN/WRN PRTNS OF FA
AGAIN CLOSEST TO MOIST/INSTAB AXIS AND FNTL BDRY SLOLY RTRNG NEWD AS
WRMFNT.  BEING N OF FNT AND WITH PCPN AND CLDS DURG MRNG HRS...XPCT
TEMPS TO MOV VERY LTL TIL AFTN WHEN SOME SUNSHINE IS XPCTD.  FAIRLY
DP ELY FLO WON/T HELP TEMPS WRMUP EITHER.  GENERALLY WENT MAV/FWC
BLEND...BUT LEANED COOL IN N FURTHEST FM FNT.

PLAN TO EXTEND FLOOD WATCH ACRS CURRENT GRPG AND ADD TO IT NRN FA.
RAFL HAS TAPERED OFF IN CURRENT WATCH AREA...BUT PSBL REDVLPMT IN
MRNG HRS OVR ALREADY SATURATED GRNDS WL REMAIN THREAT.  TRAINING OF
CELLS ACRS NRN FA ALSO A PSBLTY SO WL ADD THIS TO FFA.

FOR TNGT...WRMFNT WL MOV THRU FA...MAINLY DURG EVNG HRS.  SOME
FORCING AT LLVLS XPCTD ALG/AHD OF WRMFNT...WITH STGST XPCTD OVR NRN
FA.  FORCING SHD BE WK ENUF NOT TO WARRANT ANY POPS THO WL PLACE LOW
CHC IN NRN ZONES.

FOR WED...MUCH WRMR.  SLY LLVL FLO WITH H850 TEMPS 20 C OR HIR WL
RESULT IN WDSPRD 90S FOR MAXES.  THIS TENDS TO FAVOR MAV NUMBERS.
DWPTS IN MID 70S WITH TEMPS IN LOW-MID 90S WL PUSH HEAT ADVSRY
CRITERIA IN STL CITY.  FOR NOW WITH NR-TERM CONCERNS DOMINATING
FCST...WL HOLD OFF TIL OTR THINGS BCM CLEARER.

WED NGT INTO THU...CONTINUATION OF HOT/WRM TEMPS WITH SFC FNT
SETTLING NR MO/IA BORDER LATE WED NGT AND CONTG INTO THU AS IT
/RUNS/ INTO UPR LVL HI.  AMS SHD BE WELL CAPPED ACRS MOST OF
FA...XCPT FOR NRN FA.  THIS AREA MAY SEE SOME SPILLOVER CONVECTION
FM LIKELY MCS TO THE N WED NGT AND CONT INTO THU.

PRELIMINARY NUMBERS FOR COORDINATION PURPOSES ONLY...

UIN TB 078/069 092/073 088 04732
COU TB 086/071 092/073 092 04822
JEF TB 086/071 092/073 092 04822
STL BG 085/073 094/078 094 04422
SLO BB 083/068 092/073 091 04322
FAM TB 086/071 092/073 093 04722

.STL...FLOOD WATCH NE/CNTRL/SE MO/W CNTRL IL THIS MRNG.
TES

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
333 AM CDT TUE AUG 20 2002

TIME(CDT)  .....CITY LOCATION..... STATE  ...EVENT/REMARKS...
           ....COUNTY LOCATION....

1020 PM    STEELVILLE                MO   WIND DAMAGE
08/19/02   CRAWFORD                       NUMEROUS TREES AND POWER
                                          LINES DOWNED. REPORTED BY
                                          CRAWFORD COUNTY SHERIFFS
                                          DEPARTMENT.