Supercell thunderstorms developed in the afternoon and evening north of a warm front that ran from Southern Iowa into Central Illinois.  Three distinct supercells produced a majority of the wind, hail, and heavy rain reports from Jefferson County Iowa into Henry County Illinois.  Mercer County Illinois was under tornado warnings on a continuous basis for 2 hours.  Officials at a high school track meet in Aledo, Illinois ushered all students into the safety of the school resulting in no injuries.  The training of the supercells from Louisa County Iowa to Henry County Illinois dumped heavy rain over the Edwards River and Pope Creek basins in Illinois with radar estimating 9 inches of rain.  Actual amounts varied due to large amounts of hail with the storms.  Cambridge Illinois estimated 7 to 8 inches of rain fell in the town.  Illinois Route 17 was closed due to flooding between Aledo and Viola with Illinois Route 94 closed south of Aledo.  In Andover Illinois, two thirds of the town had basements flooded.  Toward the end of the event a bow echo developed in Henry County Illinois and raced east across Bureau and Putnam counties.  The fire department in Standard, Illinois measured a 69 knot (80 mph) wind gust when the bow echo moved through.  In Clinton, Iowa, a lightning strike started a warehouse fire at the Nestle Purnina Complex.

Hail in BENTON, IOWA
From 30-APR-03 19:20:00 to 30-APR-03 19:20:00 (CST)
Location: URBANA
Magnitude: 1.75 
Property damage: 400K
Reported by: TRAINED SPOTTER

Hail in JEFFERSON, IOWA
From 30-APR-03 16:45:00 to 30-APR-03 16:45:00 (CST)
Location: PACKWOOD
Magnitude: 1.25 
Property damage: 50K
Reported by: TRAINED SPOTTER

Lightning in CLINTON, IOWA
From 30-APR-03 21:32:00 to 30-APR-03 21:32:00 (CST)
Location: CLINTON
Property damage: 10K
Crop damage: 0K
Reported by: NEWSPAPER

Warehouse fire at Purina complex

Flash Flood in LOUISA, IOWA
From 30-APR-03 21:30:00 to 30-APR-03 23:30:00 (CST)
Location: WAPELLO
Magnitude: 5 
Property damage: 500K
Reported by: EMERGENCY MANAGER

US 61 covered with water

Hail in MUSCATINE, IOWA
From 30-APR-03 19:15:00 to 30-APR-03 19:15:00 (CST)
Location: MUSCATINE
Magnitude: 0.75 
Reported by: TRAINED SPOTTER

Hail in HENRY, IOWA
From 30-APR-03 16:59:00 to 30-APR-03 16:59:00 (CST)
Location: MT PLEASANT
Magnitude: 0.88 
Reported by: TRAINED SPOTTER

Hail in BUCHANAN, IOWA
From 30-APR-03 19:26:00 to 30-APR-03 19:26:00 (CST)
Location: AURORA
Magnitude: 0.75 
Reported by: LAW ENFORCEMENT

Hail in WASHINGTON, IOWA
From 30-APR-03 16:11:00 to 30-APR-03 16:11:00 (CST)
Location: CRAWFORDSVILLE
Magnitude: 0.75 
Reported by: LAW ENFORCEMENT

Hail in HENRY, IOWA
From 30-APR-03 19:23:00 to 30-APR-03 19:23:00 (CST)
Location: MT PLEASANT
Magnitude: 0.88 
Reported by: TRAINED SPOTTER

Hail in LOUISA, IOWA
From 30-APR-03 17:40:00 to 30-APR-03 17:40:00 (CST)
Location: MORNING SUN
Magnitude: 2.75 
Property damage: 4M
Reported by: EMERGENCY MANAGER

Hail in BENTON, IOWA
From 30-APR-03 19:26:00 to 30-APR-03 19:26:00 (CST)
Location: URBANA
Magnitude: 1.00 
Property damage: 100K
Reported by: EMERGENCY MANAGER

Hail in BENTON, IOWA
From 30-APR-03 19:09:00 to 30-APR-03 19:09:00 (CST)
Location: VINTON
Magnitude: 0.75 
Reported by: EMERGENCY MANAGER

Hail in LOUISA, IOWA
From 30-APR-03 16:45:00 to 30-APR-03 16:45:00 (CST)
Location: WAPELLO
Magnitude: 0.75 
Reported by: TRAINED SPOTTER

Funnel Cloud in LOUISA, IOWA
From 30-APR-03 17:42:00 to 30-APR-03 17:42:00 (CST)
Location: MORNING SUN
Reported by: LAW ENFORCEMENT

Hail in HENRY, IOWA
From 30-APR-03 17:30:00 to 30-APR-03 17:30:00 (CST)
Location: MT UNION
Magnitude: 1.00 
Property damage: 10K
Reported by: TRAINED SPOTTER

Jct Iowa 78 & County X23

Funnel Cloud in LOUISA, IOWA
From 30-APR-03 17:04:00 to 30-APR-03 17:04:00 (CST)
Location: WAPELLO
Reported by: TRAINED SPOTTER

Possible funnel

Hail in HENRY, IOWA
From 30-APR-03 17:03:00 to 30-APR-03 17:03:00 (CST)
Location: MT PLEASANT
Magnitude: 1.75 
Property damage: 50K
Reported by: TRAINED SPOTTER

Hail in LOUISA, IOWA
From 30-APR-03 17:40:00 to 30-APR-03 17:40:00 (CST)
Location: WAPELLO
Magnitude: 1.75 
Property damage: 1M
Reported by: EMERGENCY MANAGER

Hail in WASHINGTON, IOWA
From 30-APR-03 18:25:00 to 30-APR-03 18:25:00 (CST)
Location: RIVERSIDE
Magnitude: 1.75 
Property damage: 100K
Reported by: LAW ENFORCEMENT

Hail in LOUISA, IOWA
From 30-APR-03 17:35:00 to 30-APR-03 17:35:00 (CST)
Location: WAPELLO
Magnitude: 0.88 
Reported by: LAW ENFORCEMENT

Tornado in LOUISA, IOWA
From 30-APR-03 17:35:00 to 30-APR-03 18:20:00 (CST)
Location: MORNING SUN
Tornado F-scale: F0
Property damage: 200K
Reported by: NWS STORM SURVEY

Path narrowed to 50 yards

Heavy Rain in WASHINGTON, IOWA
From 30-APR-03 19:04:00 to 30-APR-03 19:04:00 (CST)
Location: KALONA
Magnitude: 2 
Property damage: 30K
Reported by: TRAINED SPOTTER

Street flooding

Funnel Cloud in DES MOINES, IOWA
From 30-APR-03 17:25:00 to 30-APR-03 17:25:00 (CST)
Location: YARMOUTH
Reported by: TRAINED SPOTTER

Hail in LOUISA, IOWA
From 30-APR-03 17:02:00 to 30-APR-03 17:02:00 (CST)
Location: GRANDVIEW
Magnitude: 1.00 
Property damage: 20K
Reported by: TRAINED SPOTTER

Hail in LOUISA, IOWA
From 30-APR-03 17:04:00 to 30-APR-03 17:04:00 (CST)
Location: WAPELLO
Magnitude: 0.75 
Reported by: TRAINED SPOTTER

Heavy Rain in JEFFERSON, IOWA
From 30-APR-03 19:28:00 to 30-APR-03 19:28:00 (CST)
Location: FAIRFIELD
Magnitude: 2 
Property damage: 50K
Reported by: NWS EMPLOYEE(OFF DUTY)

Funnel Cloud in LOUISA, IOWA
From 30-APR-03 16:46:00 to 30-APR-03 16:46:00 (CST)
Location: ELRICK
Reported by: TRAINED SPOTTER

Hail in HENRY, IOWA
From 30-APR-03 19:30:00 to 30-APR-03 19:30:00 (CST)
Location: MT PLEASANT
Magnitude: 1.00 
Property damage: 100K
Reported by: TRAINED SPOTTER

Hail in HENRY, IOWA
From 30-APR-03 17:00:00 to 30-APR-03 17:00:00 (CST)
Location: MT UNION
Magnitude: 0.88 
Reported by: EMERGENCY MANAGER

Hail in HENRY, IOWA
From 30-APR-03 17:04:00 to 30-APR-03 17:04:00 (CST)
Location: WAYLAND
Magnitude: 1.25 
Property damage: 100K
Reported by: TRAINED SPOTTER

Hail in IOWA, IOWA
From 30-APR-03 21:10:00 to 30-APR-03 21:10:00 (CST)
Location: VICTOR
Magnitude: 1.00 
Property damage: 50K
Reported by: LAW ENFORCEMENT

Hail in JEFFERSON, IOWA
From 30-APR-03 16:45:00 to 30-APR-03 16:45:00 (CST)
Location: FAIRFIELD
Magnitude: 1.25 
Property damage: 50K
Reported by: TRAINED SPOTTER

Sheriff car damaged

Hail in LOUISA, IOWA
From 30-APR-03 16:48:00 to 30-APR-03 16:48:00 (CST)
Location: GRANDVIEW
Magnitude: 1.00 
Property damage: 50K
Reported by: LAW ENFORCEMENT

Hail in WASHINGTON, IOWA
From 30-APR-03 16:45:00 to 30-APR-03 16:50:00 (CST)
Location: BRIGHTON
Magnitude: 0.75 
Reported by: TRAINED SPOTTER

Hail in JEFFERSON, IOWA
From 30-APR-03 16:37:00 to 30-APR-03 16:37:00 (CST)
Location: FAIRFIELD
Magnitude: 0.75 
Reported by: NWS EMPLOYEE(OFF DUTY)

Hail in LOUISA, IOWA
From 30-APR-03 16:48:00 to 30-APR-03 16:48:00 (CST)
Location: WAPELLO
Magnitude: 0.88 
Reported by: LAW ENFORCEMENT

Hail in LOUISA, IOWA
From 30-APR-03 18:50:00 to 30-APR-03 18:50:00 (CST)
Location: COLUMBUS JCT
Magnitude: 1.00 
Property damage: 50K
Reported by: EMERGENCY MANAGER

Hail in LOUISA, IOWA
From 30-APR-03 18:50:00 to 30-APR-03 18:50:00 (CST)
Location: COLUMBUS JCT
Magnitude: 1.75 
Property damage: 150K
Reported by: TRAINED SPOTTER

Pea hail covered ground

Hail in LOUISA, IOWA
From 30-APR-03 16:50:00 to 30-APR-03 16:50:00 (CST)
Location: WAPELLO
Magnitude: 2.75 
Property damage: 1M
Reported by: LAW ENFORCEMENT

Hail in JEFFERSON, IOWA
From 30-APR-03 18:39:00 to 30-APR-03 18:39:00 (CST)
Location: FAIRFIELD
Magnitude: 0.88 
Reported by: NWS EMPLOYEE(OFF DUTY)

Covered the ground

Hail in LOUISA, IOWA
From 30-APR-03 18:45:00 to 30-APR-03 18:45:00 (CST)
Location: COTTER
Magnitude: 1.75 
Property damage: 250K
Reported by: TRAINED SPOTTER

Hail in JEFFERSON, IOWA
From 30-APR-03 16:45:00 to 30-APR-03 16:45:00 (CST)
Location: BATAVIA
Magnitude: 1.25 
Property damage: 50K
Reported by: TRAINED SPOTTER

Thunderstorm Wind in LOUISA, IOWA
From 30-APR-03 16:50:00 to 30-APR-03 16:50:00 (CST)
Location: WAPELLO
Magnitude: 52 EG
Property damage: 50K
Reported by: LAW ENFORCEMENT

Power lines down

Funnel Cloud in LOUISA, IOWA
From 30-APR-03 16:56:00 to 30-APR-03 16:56:00 (CST)
Location: WAPELLO
Reported by: TRAINED SPOTTER