Killer Tornado in Evansville, Indiana

[Jay Barnes]

Fox news is saying there was little to no warning for *most* of the towns in the storms path...from what I have been reading/hearing I'm not so sure that's what really happened....

In any case if there was ever a good example of why folks should have a NOAA WX radio this would be it.

 

[Dan Cook]

There was a tornado warning out:

http://kamala.cod.edu/offs/KPAH/0511060747.wfus53.html

 

[Andrea Griffa]

Originally posted by Brett Adair

That is a strong indication of a tornado. Folks, we had plenty of ingredients for tornadic activity and I was just telling a friend before I went to sleep that these storms were just entering the area of highest favorable shear with many different level jet maxes converging. Sad situation.

Brett,
Did you save the base reflectivity of the supercell?

 

[Jeff Snyder]

Here's a loop (from http://www.rap.ucar.edu/weather/radar/) : http://www.rap.ucar.edu/weather/radar/disp...me=9&duration=2

KVWX was likely closer, but RAP/UCAR isn't working for that...

 

[Darin Brunin]

CNN reported that the residents had 30 minutes of warning time.

The National Weather Service had issued warnings for the area about 30 minutes before the tornado struck, but many people were asleep and were not aware of them.

 

[Mike Smith]

While I'll grant that there were embedded supercells, so much for the theory "solid lines don't produce tornadoes."

 

[David Schuttler]

Originally posted by Mike Smith
While I'll grant that there were embedded supercells, so much for the theory \"solid lines don't produce tornadoes.\"

May 22nd 2004 Neb.

 

[Mike Smith]

David,

What is your point?

Respectfully,

Mike

 

[Aaron Kennedy]

Tornado occurences are documented pretty well in QLCSs (quasi-linear convective systems).

http://ams.allenpress.com/amsonline/?reque...175%2FWAF-835.1

Of the 3828 tornadoes in the database, 79% were produced by cells, 18% were produced by QLCSs, and the remaining 3% were produced by other storm types, primarily rainbands of landfallen tropical cyclones. Geographically, these percentages as well as those based on tornado days exhibited wide variations. For example, 50% of the tornado days in Indiana were associated with QLCSs.

Aaron

 

[rdale]

"CNN reported that the residents had 30 minutes of warning time."

That would be wrong, and probably too much even if true given the number of FAR's that resulted from this event... The warning was issued at 1:47am, tornado touchdown was reportedly 1:59am CT.

 

[Mike Smith]

Aaron,

Still not sure of the point.

The following is from a University of Illinois online course:

"This supercell, north-northwest of the radar, developed within an east-west oriented solid squall line. It produced severe weather and funnel clouds, but no known tornadoes. Subjective experience suggests that such storms are not as likely to produce strong to violent tornadoes as are more isolated storms."

The same abstract you were quoting goes on to say:

"In an examination of other tornado attributes, statistically more weak (F1) and fewer strong (F2–F3) tornadoes were associated with QLCSs than with cells."

Because this study includes bow echoes (well known to produce tornadoes), the number of solid line tornadoes is low. And, as indicated above, solid lines (on the rare cases where they produce tornadoes) are thought to produce much weaker tornadoes than what occurred during the night.

The PAH NWS did a fine job on what was a rare situation.

My point is that "conventional wisdom" in meteorology can be wrong and was in this case.

Mike

 

[Glen Romine]

I'm not sure I would even classify this as a QLCS event - cells were fairly discrete at the time of the tornado. Within that segment of the line, it was more a line of discrete cells. Racy was on duty at SPC and noted this as well in the 2:13 am MCD:

SRN PORTION OF THE SQUALL LINE HAS EVOLVED INTO DISCRETE SUPERCELLS THIS MORNING. THE 2-6KM MEAN WIND HAS LARGELY REMAINED NORMAL TO THE LINE THROUGH THE LAST SEVERAL HOURS...SUGGESTING A MIXED-MODE OF LINE SEGMENTS AND INDIVIDUAL CELLS. VWP/S SUGGEST VERY STRONG LOW-LEVEL WIND FIELDS OWING TO A STRONG AGEOSTROPHIC RESPONSE TO PRESSURE FALLS ACROSS THE LWR GRTLKS REGION. 0-1KM SRH IN EXCESS OF 340 M2/S2 HAVE BEEN OBSERVED AT LOUISVILLE. GIVEN NEARLY 70 KTS OF H85-H7 FLOW...MODEST BOUNDARY LAYER MOISTURE AND PRESENCE OF SUSTAINED DISCRETE SUPERCELLS...THERE WILL BE THE THREAT FOR AN ISOLD TORNADO OR TWO ACROSS SRN IND AND WRN KY.

I grabbed an image from NCAR for the reflctivity around the time of the event:

http://www.atmos.uiuc.edu/~romine/ims/refl_0757.png

The cell of interest does has a large gap to the north, and a few lessor cells to it's SSW. The surface flow was roughly aligned the same - note shortly before the cells reached EVV that the conditions were 70/63 with a SSW wind at 15 kts. Looks like there may have been a weak pre-frontal trough leading the line - will probably do a pressure analysis later to see if there is more to be found on why this particular cell was so intense.

Expect that SPC will take a close look at this case - they never like to have a significant killer tornado without a tornado watch box out.

Glen

 

[Aaron Kennedy]

Just went through the data again.... they do look pretty discrete, so I'll agree with Glen. The more linear portion was well up towards KIND (I should check the damage locations next time ) The discrete cells then transition into more of a line a bit down the road...

With one of the cells, you can see what appears to be a hook on it for a period of time. That said, the storms were still in pretty close proximity to each other.

Mike:

Not sure of your point....

My point is that \"conventional wisdom\" in meteorology can be wrong and was in this case.

statistically more

This does not imply that they can't produce strong tornadoes.


Next rant:

This case reeks of the typical tornado that happens to hit a few mobile home parks late at night syndrome...

Considering a tornado warning was out... not sure what else you could of done. Even if it was a tornado watch, mobile home park residents should KNOW that even severe thunderstorm winds can and do kill people.

Aaron

 

[mikegeukes]

Links to the media sites in Evansville, IN

WTVW Channel 7 FOX Evansville, IN
http://www.wtvw.com/

WFIE Channel 14 NBC Evansville, IN
http://www.14wfie.com/

WEHT Channel 25 ABC Evansville, IN
http://www.abc25.com/

WEVV Channel 44 CBS Evansville, IN
http://www.wevv.com/default.asp

Evansville Courier & Press
http://www.courierpress.com/

National Weather Service Paducah
http://www.crh.noaa.gov/crnews/display_sto...id=110&source=0
http://www.crh.noaa.gov/product.php?site=p...at=ci&version=1

Mike
http://mgweather.com

 

[mikegeukes]

Other notable killer tornado days in Indiana history 1950-2005

The April 11, 1965 and April 03, 1974 were big outbreak days,
with many tornadoes being reported in the state of Indiana.

April 11, 1965 137 people killed, 1702 people injured
April 03, 1974: 47 people killed, 665 people injured

Source: NCDC Storm Events

Mike
http://mgweather.com