Alert archive / Indiana / Tornado Warnings in 2011

Tornado Warning 35, NWS Louisville, KY

April 20, 2011Jefferson County, Indiana

NWS Louisville, KY issued this tornado warning at Apr 20, 2011, 12:35 AM EDT for Jefferson County, Indiana. It was in force for 25 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
Apr 20, 2011, 12:35 AM EDT (04:35 UTC)
Expired
Apr 20, 2011, 1:00 AM EDT
In force
25 min
Issued by
NWS Louisville, KY
Area
Storm-based polygon

County Jefferson County, IN

The radar

The Louisville radar (KLVX), 107 km from the middle of the area, began a volume at 04:36 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.

The watch it was issued in

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

IssuedProductOfficeLasted
Apr 19, 10:13 PM EDTTornado WatchSPC6 hr

The nearest sounding before it

Cncnati-Daytn, OH (KILN), launched 00:00Z, 4.6 hours before the alert went out and 144 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, Cncnati-Daytn, OH at 00:00Z on 2011-04-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1686 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, Cncnati-Daytn, OH at 00:00Z on 2011-04-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 387 square meters per square second.19395878Sfc1 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
1686 J/kg
Mixed-layer CIN
-39 J/kg
Mixed-layer LCL
1003 m above ground
0-6 km bulk shear
51 kt
0-1 km storm-relative helicity
387 m²/s²
0-3 km storm-relative helicity
474 m²/s²
Significant tornado parameter
4.3
Supercell composite
18.7

Open this sounding in Storm Lab

The text

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

029 
WFUS53 KLMK 200435
TORLMK
INC077-200500-
/O.NEW.KLMK.TO.W.0035.110420T0435Z-110420T0500Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE LOUISVILLE KY
1235 AM EDT WED APR 20 2011

THE NATIONAL WEATHER SERVICE IN LOUISVILLE HAS ISSUED A

* TORNADO WARNING FOR...
  EASTERN JEFFERSON COUNTY IN SOUTH CENTRAL INDIANA...

* UNTIL 100 AM EDT...

* AT 1232 AM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO. THIS DANGEROUS
  STORM WAS LOCATED NEAR BROOKSBURG...MOVING NORTHEAST AT 65 MPH.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IN ADDITION TO THE TORNADO...WIDESPREAD HURRICANE FORCE WINDS ARE
LIKELY. SEEK SHELTER NOW!

TAKE COVER NOW. MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
STURDY BUILDING. AVOID WINDOWS. IF IN A MOBILE HOME...A VEHICLE OR
OUTDOORS...MOVE TO THE CLOSEST SUBSTANTIAL SHELTER AND PROTECT
YOURSELF FROM FLYING DEBRIS.

TO REPORT DAMAGING WINDS...LARGE HAIL...OR FLOODING TO THE NATIONAL
WEATHER SERVICE...CALL TOLL FREE AT...1...8 7 7...6 3 3...6 7 7 2...
WHEN YOU CAN DO SO SAFELY.

&&

LAT...LON 3880 8521 3879 8520 3870 8520 3870 8522
      3874 8527 3874 8532 3883 8521
TIME...MOT...LOC 0433Z 240DEG 37KT 3878 8518

$$

DK
1 follow-up statement
683 
WWUS53 KLMK 200458
SVSLMK

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE LOUISVILLE KY
1258 AM EDT WED APR 20 2011

INC077-200508-
/O.EXP.KLMK.TO.W.0035.000000T0000Z-110420T0500Z/
JEFFERSON IN-
1258 AM EDT WED APR 20 2011

...THE TORNADO WARNING FOR EASTERN JEFFERSON COUNTY HAS EXPIRED...

THE STORMS THAT PROMPTED THE WARNING HAVE MOVED OUT OF THE WARNED 
AREA. HEAVY RAINFALL AND GUSTY WINDS WILL CONTINUE OVER THE NEXT FEW 
HOURS. PONDING OF WATER ON ROADWAYS WILL BE POSSIBLE.

TO REPORT DAMAGING WINDS...LARGE HAIL...OR FLOODING TO THE NATIONAL
WEATHER SERVICE...CALL TOLL FREE AT...1...8 7 7...6 3 3...6 7 7 2...
WHEN YOU CAN DO SO SAFELY.

LAT...LON 3880 8521 3879 8520 3870 8520 3870 8522
      3874 8527 3874 8532 3883 8521
TIME...MOT...LOC 0458Z 240DEG 37KT 3891 8489

$$

MP

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 19, 10:26 PM EDTSpecial Weather StatementLMKCrawford, Dubois, Orange, Perry49 min
Apr 19, 10:51 PM EDTSevere Thunderstorm WarningLMKCrawford, Dubois, Orange, Perry24 min
Apr 19, 10:59 PM EDTTornado WarningLMKCrawford, Dubois, Orange, Perry46 min
Apr 19, 11:29 PM EDTSevere Thunderstorm WarningLMKPerry46 min
Apr 19, 11:34 PM EDTTornado WarningLMKClark, Crawford, Floyd, Harrison, Orange, Perry and 2 more41 min
Apr 19, 11:47 PM EDTTornado WarningLMKCrawford, Perry12 min
Apr 19, 11:54 PM EDTTornado WarningLMKHarrison36 min
Apr 20, 12:04 AM EDTTornado WarningLMKClark, Floyd, Harrison56 min
Apr 20, 12:17 AM EDTTornado WarningLMKClark, Floyd, Jefferson, Scott, Washington43 min
Apr 20, 12:19 AM EDTSevere Thunderstorm WarningLMKCrawford, Floyd, Harrison, Washington11 min
Apr 20, 12:25 AM EDTTornado WarningLMKClark, Jefferson50 min
Apr 20, 10:24 AM EDTRiver Flood WarningLMKClark, Floyd15 days
Apr 20, 10:24 AM EDTRiver Flood WarningLMKClark, Floyd, Harrison49 hr
Apr 20, 10:24 AM EDTRiver Flood WarningLMKCrawford, Perry17 days

Nearby

Tornado Warnings in Indiana, 2011Every tornado warning in 2011Tornadoes in 2011

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.