Alert archive / Illinois / Severe Thunderstorm Warnings in 2001

Severe Thunderstorm Warning 121, NWS Paducah, KY

August 18, 2001Perry County, Illinois

NWS Paducah, KY issued this severe thunderstorm warning at Aug 18, 2001, 8:22 PM CDT for Perry County, Illinois. It was in force for 38 min. 1 report came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued: Aug 18, 2001, 8:22 PM CDT (01:22 UTC)
Expired: Aug 18, 2001, 9:00 PM CDT
In force: 38 min
Issued by: NWS Paducah, KY
Area: Whole counties; the outline is the Mesonet’s reconstruction

County Perry County, IL

The radar

The Paducah radar (KPAH), 125 km from the middle of the area, began a volume at 01:26 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.

What was reported inside it

Time	Report	Where	Remark
Aug 18, 8:43 PM CDT	Thunderstorm Wind 50 E	Du Quoin, IL	Numerous trees and power lines were brought down by thunderstorm winds, especially in the Du Quoin area. A four-foot wide oak tree crashed through the front of a home. Dozens of families were without power, some for more than 12 hours.

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Aug 18, 3:00 PM CDT	Severe Thunderstorm Watch	SPC	6 hr

The nearest sounding before it

Lincoln, IL (KILX), launched 00:00Z, 1.4 hours before the alert went out and 239 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 118 J/kg
Mixed-layer CIN: -21 J/kg
Mixed-layer LCL: 1117 m above ground
0-6 km bulk shear: 42 kt
0-1 km storm-relative helicity: -6 m²/s²
0-3 km storm-relative helicity: 87 m²/s²
Significant tornado parameter: -0.0
Supercell composite: -0.1

Open this sounding in Storm Lab

The text

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

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 Paducah, KY wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 18, 1:20 PM CDT, 7 hours 2 minutes earlier.

Area forecast discussion, Aug 18, 1:20 PM CDT, 7 hours 2 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PADUCAH KY
120 PM CDT SAT AUG 18 2001

MAIN FORECAST CONCERN IS POTENTIAL FOR SEVERE THUNDERSTORMS THIS
EVENING. THEREAFTER...A DRY WEEK IS SHAPING UP FOR THE FORECAST
AREA. LATEST 18Z SURFACE ANALYSIS HAD LOW PRESSURE OVER SOUTHERN
WISCONSIN WITH ANOTHER LOW DEVELOPING IN NORTHWEST ILLINOIS. FROM
THE SECOND LOW...A WARM FRONT WAS EVIDENT ACROSS CENTRAL ILLINOIS
AND INDIANA...WITH A COLD FRONT TRAILING SOUTHWEST ACROSS MISSOURI
AND SOUTHEAST KANSAS. 12Z UPPER AIR ANALYSIS HAD A 564MB LOW OVER
WESTERN WISCONSIN AND ASSOCIATED 50 KNOT JET DIVING SOUTHEAST ACROSS
THE UPPER MIDWEST.

AT MIDDAY...MOST OF THE FORECAST AREA WAS BASKING IN PLENTY OF
SUNSHINE. THIS HAS HELPED TO BOOST TEMPERATURES INTO THE LOWER AND
MIDDLE 80S...WITH MSAS LI/S OF -7 TO -9 OVER MUCH OF SOUTHERN
ILLINOIS AND SOUTHEAST MISSOURI. THROUGH THE REST OF THE
AFTERNOON...THE AIR MASS WILL CONTINUE TO DESTABILIZE. THIS COMBINED
WITH INCREASING SHEAR AHEAD OF THE APPROACHING SHORTWAVE SHOULD GIVE
THE REGION A ROUND OF STRONG AND SEVERE THUNDERSTORMS...NAMELY LATE
THIS AFTERNOON AND THIS EVENING. BY MIDNIGHT...THE SURFACE COLD
FRONT IS FORECAST TO STRETCH ACROSS SOUTHWEST INDIANA AND WESTERN
KENTUCKY...WITH ANY LINGERING CONVECTION FROM THERE ON EASTWARD.

SUNDAY LOOKS PARTLY SUNNY AS LOW-LEVEL MOISTURE LINGERS BEHIND THE
DEPARTING LOW. FOR THE REST OF THE WEEK...MRF STILL TAKES THE RIDGE
CURRENTLY OVER THE WESTERN U.S. AND SHIFTS IT EAST. SO A DRY WEEK IS
EXPECTED WITH A MODERATION TO NEAR OR JUST ABOVE SEASONAL NORMS BY
THE MIDDLE PART OF THE WEEK. DESPITE THE LATEST MRF RUN...WILL KEEP
THE LATE WEEK PERIOD PARTLY CLOUDY BUT DRY SINCE THE EVENTUAL TRACK
OF CHANTAL REMAINS UNCERTAIN AND IS SEVERAL DAYS OUT.

MOS OUTPUT FROM BOTH NGM/AVN LOOK REASONABLE AND COMPARE FAVORABLY
WELL...SO WILL FOLLOW CLOSELY. THE ONLY EXCEPTION TO THIS WOULD BE
POPS FOR THIS EVENING...WHICH APPEAR TO BE UNDERDONE BY BOTH MODELS.

FIRST-PERIOD ZONE BREAKOUT AND WORDING WILL LIKELY BE DICTATED BY
WATCH BOXES IN EFFECT AT PRESS TIME. RIGHT NOW...PLAN TO EMPHASIZE
SEVERE THREAT INCLUDING BOTH LARGE HAIL AND DAMAGING WINDS OVER THE
ENTIRE AREA FOR THE EVENING HOURS.

.PAH...NONE.

RJP

In the hours before

Local storm report, Aug 18, 6:22 PM CDT, 2 hours before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE PADUCAH KY
622 PM CDT SAT AUG 18 2001

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

0557 PM    3E WALTONVILLE            IL   1.75 INCH HAIL
08/18/01   JEFFERSON                      REPORTED BY LAW
                                          ENFORCEMENT

Local storm report, Aug 18, 6:54 PM CDT, 1 hour 28 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE PADUCAH KY
654 PM CDT SAT AUG 18 2001

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

0625 PM    INA                       IL   1.75 INCH HAIL
08/18/01   JEFFERSON                      REPORTED BY THE PUBLIC

Local storm report, Aug 18, 7:44 PM CDT, 38 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE PADUCAH KY
744 PM CDT SAT AUG 18 2001

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

0725 PM    DIX                       IL   WIND DAMAGE
08/18/01   JEFFERSON                      SEVERAL LIMBS DOWN - MOST
                                          WERE 3 TO 5 INCHES IN
                                          DIAMETER. ONE LARGE LIMB
                                          WAS 12 INCHES IN
                                          DIAMETER.  REPORTED BY A
                                          COOPERATIVE OBSERVER.

The office that day

Everything else NWS Paducah, KY issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 18, 7:18 PM CDT	Severe Thunderstorm Warning	PAH	Jefferson	42 min
Aug 18, 7:37 PM CDT	Severe Thunderstorm Warning	PAH	Franklin, Hamilton	38 min
Aug 18, 7:51 PM CDT	Severe Thunderstorm Warning	PAH	Wayne	54 min
Aug 18, 7:57 PM CDT	Severe Thunderstorm Warning	PAH	Jefferson	63 min
Aug 18, 8:09 PM CDT	Severe Thunderstorm Warning	PAH	Hamilton, White	66 min
Aug 18, 8:36 PM CDT	Severe Thunderstorm Warning	PAH	Franklin, Jackson, Williamson	54 min
Aug 18, 10:11 PM CDT	Severe Thunderstorm Warning	PAH	Williamson	49 min
Aug 18, 10:50 PM CDT	Severe Thunderstorm Warning	PAH	Pulaski, Union	40 min

Nearby

Severe Thunderstorm Warnings in Illinois, 2001 Every severe thunderstorm warning in 2001

Sources

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