Severe Thunderstorm Warning 147, NWS Lincoln, IL

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LINCOLN IL
230 PM CDT THU AUG 12 1999

CONCERNS FOR THIS EVENING AND TONIGHT ARE PCPN DVLPMNT AND TIMING.

18Z SFC ANALYSIS SHOWS WRM FNT BEING HELD UP ON ITS FCSTD NORTHERN
MIGRATION. THIS IS DUE TO LEFTOVER MCS OUTFLOW BOUNDARY FM THIS AM.
OUTFLOW BOUNDARY RUNS FROM ABOUT STL TO HUF WHERE TSRA HAVE BEEN
FIRING FM LATE MRNG TIL PRESENT FM EFG TO SOUTH OF HUF. WRM FNT IS
STIL SOUTH OF THIS LINE AS PER EAST WINDS AND TEMPS STRUGGLING IN
THE 80S.  2PM SFC RPTS SHOW SOUTH WINDS IN EXTRM W IL FROM MACOMB TO
UIN.

PREFER ETA MODEL FOR THIS FCST PACKAGE. ALL MODELS INITIALIZED VERY
SIMILAR. SFC PRESS FALL BULLSEYE AT 18Z WAS OVER NW CRNR OF IL WITH
POOLING OF MOISTURE CONVERGENCE IN ERN IOWA WEST OF MOLINE PRODUCING
TSRA FM MONMOUTH TO NE HENRY COUNTY.

THIS IS THE FOCUS OF DVLPMNT FOR TSRA TO SPREAD SOUTHEAST ACROSS ILX
CWFA ALG NORTH MOVING WRM FRNT THIS EVE AND TNGT. WILL INCREASE PCPN
FROM NW TO SE THRU THE EVE AND TNGT.

PSBLTY STILL EXISTS FOR THIS DVLPMNT ALG WRM FNT TO PRODUCE BOW ECHO
AND PRODUCE DMGG WINDS TNGT. LIS PEAK ACROSS AREA AT -6 TO -8 FM
ARND 9PM TNGT THROUGH 6AM FRI WITH MAX OMEGA AND MOSTURE CONVERGENCE.

TRLG COLD FRONT EXPTCD TO MOVE ACRS C-IL ARND MIDDAY FRI WITH WND
SHFT TO W AND THEN NW. 8H PROFILER SHOWS SHARP WSHFT ALFT.

EXTDD CHARTS SHOW HIGH PRESS DOMINATE WITH DRY WX. MAX TEMPS WRM
FROM AROUND 80 SUN TO 90-93 BY TUE AS HI CENTR PASSES AND WINDS
BECOME SOUTH AGAIN MON NGT AND TUE ON BACK SIDE OF HIGH.

.ILX...NONE.