Damaging Wind in Illinois, March 20, 2003

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LINCOLN IL
218 PM CST THU MAR 20 2003

MAIN FORECAST CHALLENGE IS THE EXTENT OF PRECIPITATION AND
PRECIPITATION ENDING TRENDS EARLY TOMORROW...WITH THE CUTOFF LOW
SLOWLY PULLING EASTWARD TOWARD SOUTHERN ILLINOIS LATE TODAY.

MODELS HAVE BEEN SPEEDING UP THE MOVEMENT OF THE CUTOFF LOW...AS A
VIGOROUS UPPER LEVEL WAVE OVER NW MINNESOTA PULLS THE FIRST AHEAD.
CURRENT RADAR LOOP SHOWS ISOLATED THUNDERSTORMS MAINLY ALONG AND
EAST OF I-55 AT THIS TIME. STORMS SHOULD INCREASE IN AERIAL EXTENT
EAST AS THE AFTERNOON PROGRESSES. THIS FROM ENERGY WITH THE CUTOFF
LOW INTERSECTING WITH UNSTABLE AIRMASS. WILL INCLUDE MENTION OF
EVENING THUNDER IN EASTERN AREAS...WITH THE SVR THUNDERSTORM WATCH
IN EFFECT UNTIL 7 PM SOUTH OF I-70. REMAINDER OF THE AREA TO SEE
MORE GENERAL RAINS AS THE UPPER LOW PULLS EASTWARD TONIGHT. WITH THE
QUICKER MOVEMENT OF THE UPPER LOW...MODELS ARE NOW PULLING RAINS OUT
EARLIER FRIDAY. HAVE DROPPED MENTION OF RAIN WEST. SECONDARY UPPER
LOW IS EXPECTED TO PUSH ACROSS SOUTHERN WISCONSIN AND NORTHERN
ILLINOIS DURING THE DAY FRIDAY. DRYING AIRMASS AND DYNAMICS TO THE
NORTH SUPPORT NO RAINFALL THIS FAR SOUTH WITH THIS FEATURE.

NEXT RAIN EVENT SHAPING UP FOR LATER MONDAY INTO MIDWEEK. THIS WITH
A NORTHERN STREAM SHORTWAVE MOVEING ACROSS SOUTHERN CANADA AND
NORTHERN PLAINS STATES. THE ASSOC SURFACE FRONT IS EXPECTED TO DROP
INTO IL MONDAY. HAVE INTRODUCED CHANCE OF THUNDER NORTHWEST PORTIONS
OF CENTRAL ILLINOIS WITH THIS. THIS FRONT IS EXPECTED TO STALL OUT
ACROSS THE MIDWEST AS IT BECOMES PARALLEL WITH UPER LEVEL FLOW.
SOUTHERN STREAM SHORTWAVE ENERGY IN THE FLOW MAY BRING AN EXTENDED
CHANCE FOR RAIN INTO MID-WEEK. QUESTION IS EXACTLY WHERE. 12Z GFS
NOW TRENDING FARTHER SOUTH WITH THE SOUTHERN STREAM ENERGY. IF THIS
TREND CONTINUES...FRONT MAY STALL OUT FARTHER SOUTH...WITH NORTHWEST
CWA SPARED OF EXTENDED RAINFALL. FOR NOW...WILL CONTINUE MENTION OF
THUNDER MONDAY NIGHT THROUGH TUESDAY NIGHT...WITH CHANCE OF SHOWERS
WEDNESDAY AND WEDNESDAY NIGHT.

GUIDANCE TEMPERATURES LOOK REASONABLE AND MATCH WELL WITH LATEST
FORECAST. ONLY MINOR ADJUSTMENTS MADE TO TEMPERATURE FIELD.

.ILX...NONE

PLAHMER

ILZ027>031-036>038-040>057-061>063-066>068-071>073-211200-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE LINCOLN IL
1050 AM CST THU MAR 20 2003

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL AND
SOUTHEAST ILLINOIS.

.DAY ONE...TODAY AND TONIGHT

THUNDERSTORMS WILL DEVELOP ACROSS CENTRAL AND SOUTHEAST ILLINOIS
AREA THIS AFTERNOON.  SOME OF THESE STORMS MAY BECOME
SEVERE...MAINLY EAST OF THE ILLINOIS RIVER. THE MAIN THREAT FROM
THESE STORMS WILL BE LARGE HAIL AND DAMAGING WINDS. HOWEVER...AN
ISOLATED TORNADO IS ALSO POSSIBLE.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL LIKELY BE NEEDED THIS AFTERNOON AND EVENING.
STAY TUNED FOR FURTHER UPDATES ON THE POTENTIAL FOR SEVERE WEATHER.

&&
THIS PRODUCT...ALONG WITH OTHER WEATHER...HYDROLOGIC
AND CLIMATE INFORMATION...IS AVAILABLE ON THE WEB AT:

HTTP://WWW.CRH.NOAA.GOV/ILX (ALL IN LOWER CASE)

EH