Tornado Warning 109, NWS Lincoln, IL

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LINCOLN IL
200 PM CDT MON JUN 29 1998

18Z SFC CHART SHOWED A LOW PRSS AREA IN WRN IA WITH FRONT EXTENDING INTO
WRN KS.  STNRY FRONT ALSO EXTENDS FROM LOW IN IA ACRS NRN IA INTO SRN
WI.  BASED ON PRSS TRENDS IN ADAP...SFC LOW SHOULD PROGRESS SE INTO NRN
MO AND THEN INTO WCNTRL IL.  SAT TRENDS ALSO SHOW SEWRD MOVEMENT INTO
SRN IA.  AIR MASS OVER CNTRL IL IS RECOVERING NICELY.  TEMPS HAVE
CLIMBED INTO UPPER 80S WITH DEWPOINTS IN MID TO UPPER 70S ACRS CNTRL IL
INTO MO.  SPECIAL 18Z SOUNDING IS IN AND SHOWS WEAK CAP OF 3.5
DEGS...HOWEVER MODIFIED TO CRNT TEMPS OF 88 AND DEWPOINT OF 74...
AIRMASS IS NO LONGER CAPPED AND CAP VALUES EXCEED 4000 J/KG.  MODIFING
18Z HODOGRAPH WITH SPEED AND MOVEMENT OF STORMS IN IA...HELICITY IS OVER
100 WITH SUFFICIENT SHR.  ETA MDL FROM THIS MORN APPEARS TOO FAST WITH
MOVEMENT OF SFC BNDRIES...SO WILL SLOW IT DOWN A BIT.  ALL-IN-ALL SEVERE
WEATHER CONTS TO LOOK LIKELY WITH STRONG STORMS PRODUCING DAMAGING WINDS
AND ISOLATED TORNADOES POSSIBLE.  PW VALUES OVER 1.4 INCHES AND
SATURATED GROUND ALSO POINTS TO POSSIBLE FLASH FLOODING AND LOCALLY
HEAVY RAINS...JUSTIFING CONTUANCE OF FFA. ANOTHER ROUND LIKE LAST NIGHT
IS POSSIBLE ACROSS PORTIONS OF THE CWA SO WOULD RECOMMEND WORDING THAT
REFLECTED SUCH.

MDLS INDICATE FRONT MAKES IT THROUGH CWA BY MORNING...SO RELIEF AND DRY
WEATHER SHOULD RESULT TOMORROW WITH WINDS OUT OF NW.

RAIN WILL COOL TEMPS TONIGHT.  NW FLOW AND LOWER DEWPOINTS WILL PROVIDE
WELCOMED RELIEF TOMORROW.  GUIDANCE LOOKS REASONABLE...ESPECIALLY FAN.

FIRST PERIOD INPUT TO ARRIVE SHORTLY.

PIA  68/82  61
SPI  68/84  61
DEC  68/84  61
CMI  68/83  62
LWV  70/86  63

AUTEN

ILZ027>031-036>038-040>057-061>063-066>068-071>073-301100-

SEVERE WEATHER OUTLOOK
NATIONAL WEATHER SERVICE LINCOLN IL
1120 AM CDT MON JUN 29 1998

A STATIONARY FRONT ACROSS NORTHERN ILLINOIS AND SOUTHERN IOWA WILL
SLOWLY DRIFT SOUTH INTO CENTRAL ILLINOIS THIS AFTERNOON. THUNDERSTORMS
WILL DEVELOP ALONG THIS FRONT AS A WARM...MOIST AND UNSTABLE AIRMASS
REMAINS IN PLACE ACROSS THE AREA THIS AFTERNOON AND INTO TONIGHT.

THERE IS A MODERATE RISK THAT SOME OF THESE THUNDERSTORMS WILL BECOME
SEVERE...SO SPOTTER ACTIVATION WILL PROBABLY BE NEEDED LATER THIS
AFTERNOON AND INTO TONIGHT FOR ALL OF CENTRAL AND SOUTHEAST ILLINOIS.

AUTEN