Damaging Winds in Indiana, July 7, 2003

Name: Damaging Winds in Indiana, July 7, 2003
Start: 2003-07-07T08:09
End: 2003-07-07T08:40
Location: Indiana

July 7, 2003 · NWS LOT · 3 events in 3 counties and zones

A line of thunderstorms moved from northern Illinois into northwest Indiana during the morning of July 7th. Spotters reported wind gusts to 60 mph at Hammond, Gary, and Lowell in Lake County.

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.

A line of thunderstorms moved from northern Illinois into northwest Indiana during the morning of July 7th. Spotters reported wind gusts to 60 mph at Hammond, Gary, and Lowell in Lake County. Large tree limbs were blown down in DeMotte in Jasper County. Several trees, tree limbs and power lines were blown down across Porter county.

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 7, 5:35 AM CST, 2 hours 34 minutes earlier.

Area forecast discussion, Jul 7, 5:35 AM CST, 2 hours 34 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHICAGO IL
635 AM CDT MON JUL 7 2003

AVIATION DISCUSSION FOR 12Z TAFS

LINE OF TS AGAIN THIS MORNING PUSHING SE ACROSS EAST CENTRAL IA AND
FAR NW IL. CLOSE CALL AS TO HOW FAR EAST THIS LINE WILL MAKE IT THIS
MORNING BUT WILL TEMPO OUT TS FOR A FEW HRS THIS MORNING...THOUGH
MAIN PUSH OF THIS LINE IF IT HOLDS TOGETHER MAY GO SOUTH OF CHICAGO
TERMINALS. ATMOSPHERE VERY UNSTABLE AND WITH PLENTY OF OUT FLOW
BOUNDARIES CHANCE OF TS AGAIN THIS AFTERNOON AND THIS EVENING WITH
HELP FROM FRONT PUSHING SOUTH ACROSS UPPER MIDWEST. SO WILL MAINTAIN
TEMPO FOR LATE AFTERNOON THIS EVENING...BUT TS CAN/T BE RULED OUT AT
ANY TIME THRU THE PERIOD. WINDS SHOULD GO LIGHT WESTERLY TONIGHT AND
OUTSIDE OF ANY PRECIP CHANCES...MAY SEE SOME 3-5SM FOG.

CMS

DISCUSSION FOR MORNING GRIDS AND ZONES...

AS COLD FRONT SLOWLY APPROACHES FROM NW AND EVENTUALLY PUSHES THRU
CWFA PERIODS OF SHOWERS AND THUNDERSTORMS TO AFFLICT AREA NEXT
COUPLE DAYS WITH ONGOING SEVERE WEATHER THREAT AND PERHAPS BUILDING
THREAT OF FLOODING.  RECENT EVENTS CONTINUE TO SUGGEST ITS NOT
RELIABLE TO GET CUTE WITH TIMING BEYOND THE VERY SHORT TERM DUE TO
THOSE PESKY BOUNDARIES THAT DEVELOP AND FOCUS FURTHER CONVECTION AND
THE INABILITY OF ANY OPERATIONAL MODELS TO FORECAST THEM.

ONE SUCH BOUNDARY LAYING SE-NW ACROSS CWFA...PROBABLY SYNOPTIC SCALE
WARM FRONT...IS FOCUS OF MODEST BUT GENERALLY WEAKENING CONVECTIVE
DEVELOPMENT THIS MORNING.  HOWEVER RECENT ACTIVITY DEVELOPING
FURTHER W NORTH THIS WARM FRONT ON NOSE OF SOUTHWEST 850-925 FLOW
JET WOULD APPEAR LIKELY TO TRAVERSE THE AREA...ESPECIALLY
NORTH...THIS MORNING. PROBABLY ONE QUICK SHOT ALTHOUGH AS PER
SWOMCD, SOME STORMS MAY BE STRONG TO SEVERE. THEN EXPECT MORE
TSTORMS TO SPREAD EASTWARD FROM THE PLAINS/UPPER MS VALLEY TODAY AND
ARRIVE DURING THE AFTERNOON HOURS IN ASSOCIATION WITH A SHORT WAVE.
BASED ON SATELLITE/RADAR AND 06Z MODEL FORECASTS, BELIEVE THE MODELS
MAY BE A TAD SLOW WITH SHORT WAVE EMERGING FROM CENTRAL ROCKIES AND
SO WILL BEGIN PRECIP THREAT AFTER ABOUT 18Z IN FAR W.  AFTER THAT AS
MENTIONED...WILL NOT GET FANCY WITH TIMING. WILL JUST KEEP MENTION
OF TSTORMS IN THRU TUESDAY NIGHT WITH THE HIGHER POPS GRADUALLY
SHIFTING SOUTH WITH THE FRONT.  AT SOME POINT A FLOOD WATCH MAY BE
NEEDED IN THE SOUTH WHICH HAS HAD UPWARDS OF 6 INCHES RAIN LAST
COUPLE DAYS IN SOME SOUTHERN TIER COUNTIES.  DONT REALLY SEE A
HEAVY RAIN THREAT THERE TODAY HOWEVER....EXPECTED THE HEAVIER PRECIP
IN THE NORTH.

REGARDING WEDNESDAY>THURSDAY PRECIP.  GFS EXHIBITS SUSPICIOUS
BEHAVIOR SUGGESTING GRIDS SCALE FEEDBACK.  ALL OTHER MODELS SUGGEST
A WEAKER, MORE SOUTHERLY SURFACE WAVE TRACK.  FOR NOW WILL MAINTAIN
PRECIP FORECAST WED & WED NIGHT AND KNOCK IT OFF THURSDAY. WILL
TAPER POPS FROM MINIMAL IN NORTH TO BETTER CHANCE SOUTHERN SECTIONS.

WILL TEMPER HIGHS TODAY IN THE NORTH A COUPLE DEGREES FROM EARLIER
GRIDS IN LIGHT OF EXPECTED LONGER DURATION OF CLOUDS AND CONVECTIVE
THREAT.  STILL MAY PUSH 95 IN SOUTHERN COUNTIES.

.CHI...NONE

KAPLAN

Hazardous weather outlook, Jul 7, 5:00 AM CST, 3 hours 9 minutes before

ILZ003>006-008-010>014-019-020>023-032-033-039-INZ001-002-010-011-019
-081100-

HAZARDOUS WEATHER OUTLOOK...CORRECTED
NATIONAL WEATHER SERVICE CHICAGO IL
600 AM CDT MON JUL 7 2003

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTH CENTRAL AND NORTHEAST
ILLINOIS...NORTHWEST INDIANA...AND THE ADJACENT WATERS OF LAKE
MICHIGAN.

.DAY ONE... TODAY AND TONIGHT

THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS TODAY AND TONIGHT.
ALTHOUGH THUNDERSTORMS ARE LIKELY THIS MORNING ESPECIALLY NORTH OF I
80 MOST SHOULD REMAIN BELOW SEVERE LIMITS. THEY MAY VERY WELL
PRODUCE A LOT OF DANGEROUS CLOUD TO GROUND LIGHTNING. THE BEST
CHANCE FOR SEVERE STORMS WILL BE FROM MID AFTERNOON ON THROUGH LATE
TONIGHT. DAMAGING WINDS AND LARGE HAIL ARE THE MAIN SEVERE THREATS.

HEAT INDICES THIS AFTERNOON WILL REACH THE UPPER 90S IN MANY
AREAS...TO AROUND 105 IN SOME AREAS SOUTH OF I 80.

.DAYS TWO THROUGH SEVEN... TUESDAY THROUGH SUNDAY

THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS AGAIN TUESDAY AND
TUESDAY NIGHT FOR MOST OF THE AREA.  HEAVY RAIN IS POSSIBLE
ESPECIALLY IN SOUTHERN PORTIONS...WHICH COULD CAUSE AT LEAST SMALL
STREAM FLOODING DUE TO ALREADY SATURATED SOILS FROM THE WEEKEND
RAINS...PRIMARILY SOUTHEAST OF A BLOOMINGTON...WATSEKA...RENSSELAER
LINE.

SHOWERS AND THUNDERSTORMS WILL LINGER THROUGH WEDNESDAY...BUT ARE
NOT EXPECTED TO BE SEVERE. MORE THUNDERSTORMS COULD RETURN SATURDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTERS MAY BE NEEDED THIS AFTERNOON...FROM MID AFTERNOON ON...AND
TONIGHT.

&&

           NWS CHICAGO WEBPAGE

    HTTP://WWW.CRH.NOAA.GOV/LOT (LOWER CASE)
OR  HTTP://WEATHER.NOAA.GOV/CHICAGO (LOWER CASE)

In the hours before

Local storm report, Jul 7, 6:56 AM CST, 1 hour 13 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE CHICAGO IL
756 AM CDT MON JUL 07 2003

TIME(CDT)  .....CITY LOCATION..... STATE  ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0745 AM    2 N BYRON                 IL   WIND DAMAGE
07/07/03   OGLE                           1 TREE DOWN.  RT 2.
                                          1.5 N OF BYRON.  LIMBS
                                          DOWN IN OREGON.
                                          REPORTED BY LAW
                                          ENFORCEMENT OFFICIAL.

Local storm report, Jul 7, 6:59 AM CST, 1 hour 10 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE CHICAGO IL
759 AM CDT MON JUL 07 2003

TIME(CDT)  .....CITY LOCATION..... STATE  ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0745 AM    2 N BELVIDERE             IL   WIND DAMAGE
07/07/03   BOONE                          POWER LINES DOWN.  EST.
                                          50MPH WIND GUST.
                                          REPORTED BY EMERGENCY
                                          MANAGEMENT.

Local storm report, Jul 7, 7:16 AM CST, 53 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE CHICAGO IL
816 AM CDT MON JUL 07 2003

TIME(CDT)  .....CITY LOCATION..... STATE  ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0741 AM    GENOA                     IL   WIND DAMAGE
07/07/03   DEKALB                         TREE LIMBS DOWN. .
                                          REPORTED BY LAW
                                          ENFORCEMENT OFFICIAL.

0810 AM    GENOA                     IL   WIND DAMAGE
07/07/03   DEKALB                         MEDIUM TO LARGE TREES
                                          DOWN. REPORTED BY
                                          EMERGENCY MANAGEMENT.

Local storm report, Jul 7, 7:33 AM CST, 36 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE CHICAGO IL
833 AM CDT MON JUL 07 2003

TIME(CDT)  .....CITY LOCATION..... STATE  ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0800 AM    BELVIDERE                 IL   WIND DAMAGE
07/07/03   BOONE                          TREES AND WIRES DOWN IN
                                          BELVEDERE AND
CHERRY
                                          VALLEY.  REPORTED BY
                                          EMERGENCY MANAGEMENT.

Local storm report, Jul 7, 7:40 AM CST, 29 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE CHICAGO IL
840 AM CDT MON JUL 07 2003

TIME(CDT)  .....CITY LOCATION..... STATE  ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0800 AM    MARENGO                   IL   60 MPH TSTM GUST
07/07/03   MCHENRY                        PEA SIZE HAIL. WINDS
                                          60MPH. . REPORTED BY
                                          EMERGENCY MANAGEMENT.

0822 AM    MARENGO                   IL   70 MPH TSTM GUST
07/07/03   MCHENRY                        PEA SIZED HAIL.
                                          55-70MPH WINDS.  POWER
                                          POLES BENT OVER.
                                          NUMEROUS TREES DOWN.
                                          MARENGO UNION AREA.

Local storm report, Jul 7, 7:45 AM CST, 24 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE CHICAGO IL
845 AM CDT MON JUL 07 2003

TIME(CDT)  .....CITY LOCATION..... STATE  ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0840 AM    AURORA                    IL   WIND DAMAGE
07/07/03   KANE                           POWER LINES DOWN.  E
                                          SIDE OF HILL AVE.
                                          REPORTED BY CITY OF
                                          AURORA OFFICIAL.

The radar

The Chicago radar (KLOT), 50 km away, was scanning. The volume nearest the first event began at 14:09 UTC.

Open the radar archive at this moment

Event by event

3 thunderstorm wind. Local standard time, as filed.

Thunderstorm Wind, Lake

When: July 7, 8:09 AM CST to 8:30 AM CST
Where: Lake County, Hammond
Measured: 52 kt (60 mph) estimated gust
Reported by: EMERGENCY MANAGER
Coordinates: 41.583, -87.483

Thunderstorm Wind, Porter

When: July 7, 8:25 AM CST to 8:40 AM CST
Where: Porter County, Countywide
Measured: 57 kt (66 mph) estimated gust
Reported by: NEWSPAPER
Coordinates: 41.433, -87.067

Thunderstorm Wind, Jasper

When: July 7, 8:32 AM CST
Where: Jasper County, Demotte
Measured: 52 kt (60 mph) estimated gust
Reported by: GENERAL PUBLIC
Coordinates: 41.200, -87.200

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.

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

The same day elsewhere

Every storm in Indiana in 2003 Every state in 2003 This day in weather history Warnings in Indiana, July 2003

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: 5370271, 5370273, 5370272.