000 
TTAA00 KSTL 080950
AFDSTL

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ST LOUIS MO
345 AM CST SAT JAN 8 2000

FAST ZNL FLOW WL BE PUSHING SVRL SHTWVS ACR CNTRL U.S. NXT 48 HRS.
MDLS ARE IN PRETTY GD AGREEMENT WITH TIMING OF EACH SPCLY
CONSIDERING RPD WINDS ALFT...AND WV IMAGERY INDICATES MDLS
ARE ON THE MARK WITH FIRST 2 THAT WL BE AFFECTING AREA THRU SUN.

FIRST VORT MAX MOVING INTO RED RVR AREA ATTM GENERATING A FAIRLY
LARGE SWATCH OF PCPN FROM NE OK INTO S AR....BUT PCPN SHIELD
APRS TO BE HVG VRY DFCLT TIME EXPANDING INTO S MO.   THIS SEEMS TO
INDICATE THAT NGM/ETA 290-295K SFCS ARE CORRECT IN FCSTG BEST
MOSITURE TRNSPRT WL BE ACR AR/SE MO...WITH W-E MID LVL WNDS
HAMPERING NWD GROWTH OF RAIN AREA...SPCLY AS SYS SHRS OUT AND WKNS
WITH TIME. GOING ZNS HV POPS AS FAR N AS I-70 TDA WHICH DOESN'T LK
TOO BAD...BUT IT MAY BE ANY PCPN THAT FAR N WL BE LTL MORE THAN
SPRKLS.

AS THIS FIRST SHTWV EXITS AREA THIS EVE IT IS FCST TO TAKE DEEPER
MOISTURE WITH IT...WHILE S LO LVL FLOW WL KP AMPLE LO LVL MOISTURE
LOCKED OVR AREA FOR NXT SHTWV TO WORK ON.  MY FIRST IMPRESSION WAS
THAT LIMITED MOISTURE SHUD PREVENT MUCH IN THE WAY OF PCPN WITH
SCND SHTWV...BUT THEN I NOTED THAT ALL 3 MDLS GENERATE ANOTHER ROUND
OF PCPN TNGT AND INTO SUN AHD OF THIS SHOT OF ENERGY.  WHILE SMWHAT
DUBIOUS OF MOS POPS FOR TNGT GIVEN THE DIFFICULTY THE MDLS USUALLY
HV WITH FAST MOVG SYSTEMS...I CANT TOTALLY DISCOUNT A LO POP WITH
MODEST MOISTURE AND MODEST LFT FCST ACR AREA.

3RD TROF FCST BY AVN TO APRCH AREA LT SUN.  TIMING OF THIS FTR WULD
CAUSE MAIN IMPACT TO BE SUN NGT...DOVETAILING NICELY WITH CURRENT
ZN PKG.  NO CHGS MAJOR CHGS PLANNED TO XTNDD.

TEMP-WISE WL HEAVILY LEAN TWD COOLER FWC MAX TEMPS...AND A
LIMITED DIURNAL SWING...DUE TO CLDNS.

.STL...NONE.
TRUETT