Hail and Damaging Winds in Illinois, July 3, 2004

Name: Hail and Damaging Winds in Illinois, July 3, 2004
Start: 2004-07-03T14:00
End: 2004-07-03T14:45
Location: Illinois

July 3, 2004 · NWS LOT · 3 events in 2 counties and zones

On the afternoon of July 3, an upper-level system moving northeastward from the St. Louis, MO area, across Illinois, into southern Wisconsin.

Where it happened

Every event with a place to put it. Tap one for its entry below.

Tornadoes
Tropical storms and surge
Floods
Wind
Hail
Winter weather
Heat and drought
Cold
Fire, smoke and dust
Marine and coastal
Other

Open the live radar over this ground

The toll

Deaths: 0
Injuries: 0
Property damage: None recorded
Crop damage: None recorded
Events: 3

Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.

What happened

The episode as NWS LOT wrote it up.

On the afternoon of July 3, an upper-level system moving northeastward from the St. Louis, MO area, across Illinois, into southern Wisconsin. This system produced several bands of showers and thunderstorms, which moved northeastward across the region. One band moved through the Chicago metro area and southern Lake Michigan, producing isolated large hail and strong wind gusts.

What forecasters said that day

The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Chicago, IL wrote its last area forecast discussion before the first event at Jul 3, 1:46 PM CST, 14 minutes earlier.

Area forecast discussion, Jul 3, 1:46 PM CST, 14 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHICAGO IL
246 PM CDT SAT JUL 3 2004

.DISCUSSION...

FOCUS OF FORECAST ON SHORTER TERM WITH UPPER SYSTEM AND HOLIDAY
FESTIVITIES THROUGH MONDAY.

CLOSED UPPER LOW HIGHLY EVIDENT IN GOES VAPOR IMAGERY OVER XTRM NERN
MO THIS AFTN...WITH VORT MAX NOTED MOVING OUT OF BASE OF TROUGH AND
LIFTING NORTHEAST INTO CNTRL IL. WIDESPREAD INCRS IN DIUNAL
CONVECTION OCCURRING AS IS TYPICAL WITH THESE FEATURES IN WARM
SEASON. NWP CONSISTENT IN MOVG UPPER CIRCULATION NORTHEAST ACROSS
NRN IL TONIGHT...WITH ETA PREFERRED IN SLIGHTLY SLOWER PROGRESS
TYPICAL OF CLOSED UPPER SYSTEMS. THUS WILL CONTINUE CATEGORICAL POPS
THROUGH EVENING THEN TAPER TO CHANCE POPS ACROSS SOUTHWESTERN CWA
AFTER MIDNIGHT AS TROUGH AXIS MOVES NORTHEAST AND DIURNAL LULL IN
CONVECTION DEVELOPS. WITH SLOWER SOLUTION OF ETA PREFERRED HAVE KEPT
LOW CHC POPS INTO SUNDAY MORNING AS UPPER TROUGH SLOWLY PULLS OUT.
HAVE ELECTED TO KEEP LOW CHC POPS CWA WIDE INTO AFTN AS WELL...AS
ALL GUIDANCE BRINGING SECONDARY S/WV INTO MID/UPPER MS VLY BY AFTN.
THIS APPEARS TO HAVE CONTINUITY WITH S/WV CURRENTLY EVIDENT IN VAPOR
IMAGERY OVER WY...THOUGH GFS APPEARS TO OVERDO STRENGTH OF THIS
FEATURE THRU 24-36 HOURS AS RESULT OF CONVECTIVE FEEDBACK. ETA/META
INDICATE LLVL MOISTURE REMAINING IN PLACE ACROSS FCST AREA SUN AFTN
WITH SFC DEWPOINTS IN UPPER 60S. META FCST SOUNDINGS SHOWING
MODERATE INSTALBILITY DVLPG SBCAPE OF 2000 J/KG BY AFTN ESPECIALLY
SRN CWA...WITH UNIDIRECTIONAL WESTERLY SHEAR PROFILES. SPC HAS
INCLUDED SERN HALF OF CWA IN DAY 2 SLGT RISK. APPEARS FCST AREA TO
DRY OUT SUN NGT AS COLD FRONT SLIPS IN FROM THE NORTH AND WEAK S/WV
RIDGING DVLPS BY MONDAY MORNING.

FRONT SAGS INTO/JUST SOUTH OF FCST AREA MON MORNING...BEFORE NEXT
S/WV MOVES ACROSS CNTRL PLAINS AND LIFTS FRONT BACK NORTH LATE MON
AND MON NGT. NXT CHC POPS IN PLACE WITH NORTHWARD MOVEMENT OF THE
FRONT FAR SOUTHWEST SECTIONS MON AFTN AND ENTIRE CWA MON NGT.

TEMP WISE...HAVE RAISED MIN TEMPS A BIT TNGT WITH DEWPOINTS HANGING
IN UPPER 60S. OTHER SIG CHANGE WAS TO ACCOUNT FOR COOLER MAXES ON
MON N/NERN COUNTIES WITH NE FLOW OF LAKE MICH.

RATZER

&&

.AVIATION...

FOR 18Z TAFS...CURRENT EXPANSION OF TSRA WILL MOVE INTO THE
TERMINALS LATER THIS AFTERNOON. MFVR TO IFR CIGS/VIS IS
ANTICIPATED ASSOCIATED WITH THE STRONGEST CELLS. TSRA WILL
TRANSITION OVER TO SHRA BY 00Z AND PERSIST UNTIL NEAR 06Z.
OVC CIGS ANTICPATED TO LOWER AFTER THE PRECIP ENDS TO NEAR 1000
FT AGL OVERNIGHT GIVEN HIGH MOISTURE FIELDS. SHORTLY AFTER
SUNRISE CIGS SHOULD BECOME BKN AOA 3000 FT AGL. SFC WINDS
TONIGHT WILL PERSIST OUT OF TEH SE THEN VEER AFTER MINIGHT TO THE
SW...WESTERLY FLOW TOMORROW.

&&

.LOT...WATCHES/WARNINGS/ADVISORIES...
.IL...NONE.
.IN...NONE.
.LK MI...NONE.

Hazardous weather outlook, Jul 3, 2:00 PM CST, 0 minutes before

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE CHICAGO IL
300 PM CDT SAT JUL 3 2004

ILZ003>006-008-010>014-019>022-023-032-033-039-INZ001-002-010-011-019
-041100-
WINNEBAGO-BOONE-MCHENRY-LAKE IL-OGLE-LEE-DE KALB-KANE-DU PAGE-COOK-
LA SALLE-KENDALL-GRUNDY-WILL-KANKAKEE-LIVINGSTON-IROQUOIS-FORD-
LAKE IN-PORTER-NEWTON-JASPER-BENTON-
300 PM CDT SAT JUL 3 2004

THIS PORTION OF THE HAZARDOUS WEATHER OUTLOOK IS FOR NORTH CENTRAL
AND NORTHEAST ILLINOIS...AND NORTHWEST INDIANA.

.DAY ONE...THIS AFTERNOON AND TONIGHT

RAIN SHOWERS AND OCCASIONAL THUNDERSTORMS WILL BECOME NUMEROUS ACROSS THE
REGION THIS AFTERNOON AND INTO TONIGHT. THE MAIN CONCERN FROM THE ACTIVITY
WILL BE LOCALLY BRIEF HEAVY RAIN ASSOCIATED WITH THE STRONGER STORMS.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

THERE WILL BE A CHANCE OF SHOWERS AND THUNDERSTORMS IN THE MORNING
ON SUNDAY. THE NEXT CHANCE OF SHOWERS AND THUNDERSTORMS WILL BE LATE
MONDAY NIGHT THROUGH EARLY WEDNESDAY MORNING.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL NOT BE NEEDED TODAY AND TONIGHT.

&&

COMPLETE FORECAST INFORMATION IS AVAILABLE ON THE
NWS CHICAGO WEBPAGE: WWW.CRH.NOAA.GOV/LOT (LOWER CASE)

LMZ740>746-766-041100-
WINTHROP HARBOR IL TO NEW BUFFALO MI-
LAKE MICHIGAN-
300 PM CDT SAT JUL 3 2004

THIS PORTION OF THE HAZARDOUS WEATHER OUTLOOK IS FOR THE ILLINOIS
AND INDIANA WATERS OF LAKE MICHIGAN.

.DAY ONE...THIS AFTERNOON AND TONIGHT

RAIN SHOWERS AND OCCASIONAL THUNDERSTORMS ARE EXPECTED THROUGH TONIGHT.
SOME OF THE SHOWERS AND THUNDERSTORMS MAY PRODUCE PERIODS OF HEAVY RAIN.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

THERE WILL BE A CHANCE OF SHOWERS AND THUNDERSTORMS IN THE MORNING
ON SUNDAY. THE NEXT CHANCE OF SHOWERS AND THUNDERSTORMS WILL BE LATE
MONDAY NIGHT THROUGH EARLY WEDNESDAY MORNING.

&&

COMPLETE FORECAST INFORMATION IS AVAILABLE ON THE
NWS CHICAGO WEBPAGE: WWW.CRH.NOAA.GOV/LOT (LOWER CASE)

05

The radar

The Chicago radar (KLOT), 30 km away, was scanning. The volume nearest the first event began at 19:57 UTC.

Open the radar archive at this moment

Event by event

2 thunderstorm wind, 1 hail. Local standard time, as filed.

Thunderstorm Wind, Cook

When: July 3, 2:00 PM CST
Where: Cook County, Alsip
Measured: 50 kt (58 mph) estimated gust
Reported by: LAW ENFORCEMENT
Coordinates: 41.667, -87.733

Large limbs were torn off of trees.

Thunderstorm Wind, Cook

When: July 3, 2:30 PM CST
Where: Cook County, Lyons
Measured: 50 kt (58 mph) estimated gust
Reported by: TRAINED SPOTTER
Coordinates: 41.817, -87.800

A large tree was knocked over on Joliet Ave.

Hail, Du Page

When: July 3, 2:40 PM CST to 2:45 PM CST
Where: Du Page County, Lombard
Measured: 0.75 in hail
Reported by: TRAINED SPOTTER
Coordinates: 41.883, -88.017

What these are

Thunderstorm Wind: Winds from a thunderstorm of 50 knots (58 mph) or more, or lower winds that caused damage or casualties. Measured gusts are marked MG, estimated EG.
Hail: Hail three-quarters of an inch or larger, or smaller hail that caused damage, filed with the largest stone measured.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

Every storm in Illinois in 2004 Every state in 2004 This day in weather history Warnings in Illinois, July 2004

Sources

NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 5412811, 5412812, 5412813.