Alert archive / Illinois / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 28, NWS Chicago, IL

August 19, 2002Ford County, Illinois

NWS Chicago, IL issued this severe thunderstorm warning at Aug 19, 2002, 1:10 AM CDT for Ford County, Illinois. It was in force for 55 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Aug 19, 2002, 1:10 AM CDT (06:10 UTC)
Expired
Aug 19, 2002, 2:05 AM CDT
In force
55 min
Issued by
NWS Chicago, IL
Area
Counties, with a storm outline in the text

County Ford County, IL

The radar

The Lincoln radar (KILX), 87 km from the middle of the area, began a volume at 06:12 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

Did it verify

Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this severe thunderstorm warning while it was in force. That is not proof nothing happened: reports are thin where few people live.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The nearest sounding before it

Lincoln, IL (KILX), launched 00:00Z, 6.2 hours before the alert went out and 45 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Lincoln, IL at 00:00Z on 2002-08-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 523 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Lincoln, IL at 00:00Z on 2002-08-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 172 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
523 J/kg
Mixed-layer CIN
-272 J/kg
Mixed-layer LCL
743 m above ground
0-6 km bulk shear
42 kt
0-1 km storm-relative helicity
172 m²/s²
0-3 km storm-relative helicity
282 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.1

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

133 
WUUS53 KLOT 190610
SVRCHI
ILC053-190705-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE CHICAGO IL
107 AM CDT MON AUG 19 2002

THE NATIONAL WEATHER SERVICE IN CHICAGO HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  FORD COUNTY IN EAST CENTRAL ILLINOIS

* UNTIL 205 AM CDT

* AT 105 AM CDT...DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM 17
  MILES WEST OF GIBSON CITY...MOVING EAST AT 35 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...

  GIBSON CITY AROUND 130 AM CDT.

THE SEVERE THUNDERSTORMS ARE CAPABLE OF PRODUCING
 HAIL UP TO THE SIZE OF QUARTERS.
 VERY HEAVY RAINFALL...WHICH MAY CAUSE LOCALIZED FLOODING.

GET INDOORS AND STAY AWAY FROM WINDOWS.

REPORT SEVERE WEATHER TO THE NEAREST LAW ENFORCEMENT AGENCY. THEY
WILL RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE.

LAT...LON 4060 8865 4046 8865 4042 8814 4060 8814

BRUMER

NNNN

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, 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 this severe thunderstorm warning went out at Aug 18, 2:05 PM CDT, 11 hours 5 minutes earlier.

Area forecast discussion, Aug 18, 2:05 PM CDT, 11 hours 5 minutes before
AREA GRIDDED FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHICAGO IL
205 PM CDT SUN AUG 18 2002

VAPOR IMAGERY SUPPORTING A STRONG VORT CROSSING INTO WESTERN DAKOTAS
FORECAST TO TRACK ACROSS WISCONSIN TONIGHT. THUS LATEST AVN/ETA RUNS
HAVE ABOUT AS MUCH LIFT IN NORTHERN PART OF CWFA DURING THE NIGHT AS
TO THE SOUTH. SO MOS BLEND YIELDING LIKELY POPS EVEN FAR NORTH IS
ACCEPTABLE.  MORE OF THIS LIFT WILL PROBABLY NEED TO GO INTO
SATURATION WHICH MAY DELAY ONSET OF PRECIP A BIT.  GOES SOUNDER
DATA, WHERE NOT OBSCURED BY CLOUDS, STILL SHOWING BEST PWS
APPROACHING 2 BOTTLED UP OVER SOUTHERN KANSAS. AS DISCUSSED
EARLIER, HEAVY RAIN THREAT (TREAT?) SUCH AS IT IS, APPEARS CONFINED
TO SOUTHERN COUNTIES. AND IN AMOUNTS EXPECTED TO FALL, IT SHOULD BE
VERY WELCOME. LINGERING MORNING SHOWERS A THREAT OVER ALL BUT FAR
NORTHWEST COUNTIES.  ETA SLOWER TO DRY THINGS OUT BUT WILL GO WITH
FASTER AVN/NGM SOLUTION THAT SHOULD YIELD ABUNDANT SUNSHINE BY
AFTERNOON IN THE NORTHWEST HALF OF THE CWFA.

ETA/AVN/NGM MOS BLEND GENERALLY USED FOR TEMPS.

DELIGHTFUL DAY EXPECTED TUESDAY BEFORE RETURN SOUTHERLY FLOW
BEGINS.  TUESDAY NIGHT INTO WEDNESDAY PRIMARY FOCUS OF 850 JET IS
NORTHWARD THROUGH THE PLAINS AND INTO UPPER MIDWEST.  SUPPOSE SOME
OF THIS DECAYING ACTIVITY COULD BLEED SOUTHEAST ALONG THICKNESS
CONTOURS INTO OUR NORTHERN COUNTIES, BUT FOR NOW WILL STICK WITH
GOING DRY FORECAST.  LATEST AVN RUN IN AGREEMENT WITH EARLIER HPC
GUIDANCE AND GOING FORECAST ON A SMALL THREAT OF PRECIP EARLY ON
THURSDAY NORTHERN CWA. PERHAPS AIDED BY A BOUNDARY LEFTOVER FROM THE
DAY BEFORE.

OTHERWISE FOR DAYS 4-7 MADE SMALL, MOSTLY UPWARD CHANGES TO HPC TEMP
GUIDANCE TO BLEND TOWARD PREVIOUS LOCAL FORECAST.  PRECIP GUIDANCE
ACCEPTED.

.CHI...NONE

KAPLAN

In the hours before

Local storm report, Aug 18, 7:40 PM CDT, 5 hours 30 minutes before
PRELIMINARY LOCAL STORM REPORT TEST TEST TEST TEST
NATIONAL WEATHER SERVICE CHICAGO IL
740 PM CDT SUN AUG 18 2002

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

0740 PM    TEST                     IN    TEST
08/18/02   TEST                           TEST

TEST TEST TEST TEST TEST TEST

The office that day

Everything else NWS Chicago, IL issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 19, 2:12 AM CDTFlash Flood WarningLOTFord, Iroquois4 hr
Aug 19, 6:12 AM CDTFlash Flood WarningLOTFord, Iroquois3 hr

Nearby

Severe Thunderstorm Warnings in Illinois, 2002Every severe thunderstorm warning in 2002

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.