Tornado Safety Week - Local Tornadoes

UPDATE: Friday March 8, 2012:  From the "best laid plans of mice and men" category (thanks to Robert Burns for writing the poem and John Steinbeck for making the phrase famous), snowfall took up two days this week and recovery one. As a result I did not get as much done as I had hoped. I did get time to plot these maps of Cincinnati area tornadoes, despite corrupt files and the usual challenges. Note the 2012 tornadoes are NOT included in the maps of tornadoes by F/EF scale. The Storm Prediction Center is finalizing their work on the 2012 data. I will update these when the data is available.

In honor of tornado safety week each night  I will post information on severe weather and tornadoes. This is a map showing all tornadoes in and around the FOX19 viewing area since 1950. Prior to 1950 data is scarce and not reliable and official digital records of tornadoes begin in 1950.

The only F5/EF5 tornadoes in our region occurred during the April 3-4, 1974 Super Outbreak.  All tornadoes since 1950 around here are shown in the maps above. Click on the image for a larger view.

F/EF5 Torndoes are fairly rare. All the F/EF5 in the U.S. are show below, courtesy of NOAA SPC.

List of all F5/EF5 Tornadoes in the U.S. 1950 - 2012

State with the most F/EF5s - Oklahoma - 8
Month With the Most F/EF5s - May with 21)
Single Day with the most F/EF5s - April 3, 1974 - 7
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#       DATE                    LOCATION
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No EF5 Tornadoes Touched Down in 2012

60      May 31, 2013        El Reno, OK (at 2.6 miles the widest tornado on record)
59      May 20, 2013        New Castle - Moore, OK
58      May 24, 2011        El Reno/Piedmont OK
57      May 22, 2011        Joplin MO
56      Apr 27, 2011         Rainsville/Sylvania AL
55      Apr 27, 2011         Preston MS
54      Apr 27, 2011         Hackleburg/Phil Campbell AL
53      Apr 27, 2011         Smithville MS

No EF5 Tornadoes Touched Down 2009 - 2010

52      May 25, 2008        Parkersburg IA
51      May 4, 2007          Greensburg KS

No EF5 Tornadoes Touched Down 2000 - 2006

50      May 3, 1999          Bridge Creek/Moore OK
49      Apr 16, 1998         Waynesboro TN
48      Apr 8, 1998           Oak Grove/Pleasant Grove AL
47      May 27, 1997        Jarrell TX
46      Jul 18, 1996          Oakfield WI

No EF5 Tornadoes Touched Down 1993 - 1995

45       June 16, 1992       Chandler MN
44       Apr 26, 1991        Andover KS
43       Aug 28, 1990        Plainfield IL
42       Mar 13, 1990        Goessel KS
41      Mar 13, 1990         Hesston KS

No EF5 Tornadoes Touched Down 1986 -1989

40      May 31, 1985        Niles OH
39      Jun 7, 1984            Barneveld WI

No EF5 Tornadoes Touched Down in 1983

38      Apr 2, 1982           Broken Bow OK

No EF5 Tornadoes Touched Down 1978 - 1981

37      Apr 4, 1977           Birmingham AL
36      Jun 13, 1976          Jordan IA
35      Apr 19, 1976         Bownwood TX
34      Mar 26, 1976        Spiro OK

No EF5 Tornadoes Touched Down in 1975

33      Apr 3, 1974          Guin AL
32      Apr 3, 1974          Tanner AL
31      Apr 3, 1974          Mt. Hope AL
30      Apr 3, 1974          Sayler Park OH
29      Apr 3, 1974          Brandenburg KY
28      Apr 3, 1974          Xenia OH
27      Apr 3, 1974          Daisy Hill IN


26       May 6, 1973           Valley Mills TX

No EF5 Tornadoes Touched Down in 1972

25      Feb 21, 1971           Delhi LA
24      May 11, 1970          Lubbock TX

No EF5 Tornadoes Touched Down in 1969

23      Jun 13, 1968           Tracy MN
22      May 15, 1968         Maynard IA
21      May 15, 1968         Charles City IA
20     Apr 23, 1968           Gallipolis OH

No EF5 Tornadoes Touched Down in 1967

19      Oct 14, 1966           Belmond IA
18      Jun 8, 1966             Topeka KS
17      Mar 3, 1966            Jackson MS
16      May 8, 1965            Gregory SD
15      May 5, 1964            Bradshaw NE
14      Apr 3, 1964            Wichita Falls TX

No EF5 Tornadoes Touched Down 1961 - 1963

13      May 5, 1960             Prague OK

No EF5 Tornadoes Touched Down in 1959

12      Jun 4, 1958              Menomonie WI
11      Dec 18, 1957           Murphysboro IL
10      Jun 20, 1957            Fargo ND
9       May 20, 1957           Ruskin Heights MO
8       Apr 3, 1956              Grand Rapids MI
7       May 25, 1955            Udall KS
6       May 25, 1955            Blackwell OK

No EF5 Tornadoes Touched Down in 1954

5        Dec 5, 1953            Vicksburg MS
4        Jun 27, 1953            Adair IA
3        Jun 8, 1953              Flint MI
2        May 29, 1953           Ft. Rice ND
1        May 11, 1953           Waco TX

No EF5 Tornadoes Touched Down 1950 - 1952

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The Long Life of the March 2, 2012 Supercells

Supercell thunderstorms are special animals.  They represent a balance between expending energy and taking energy in.  The imported energy is mainly water vapor. It condenses when lifted.  The heat liberated helps drive the supercell, sometimes for hours.

A non-descript thunderstorm has an updraft that is vertical. The lifted water vapor, condenses, raindrops grow then fall as torrential rain right  through the updraft. It's like pouring water down a chimney - the fire will go out. In the case of a non-descript thunderstorm the rain drops push  against the updraft and that toe-to-toe battle limits  the storm's life to between 15 and 45 minutes.

The supercell lives to be a senior citizen in t he world of thunderstorms. They have been known to persist for 12 hours because their updraft is tilted and the rain falls out ahead of the updraft. There is no battle between the rising air and the falling rain in a supercell. So ... it lives a long time.

The animation is from the Wilmington NWS NEXRAD Doppler Radar.  The arrow points to where the cells that would cause the tornadoes are first visible, then follows the storms.  The Paducah, KY radar saw the cells born in southeast Missouri. In the second time lapse the three supercells that caused the Holton, IN, the Crittenden-Piner-Fiskburg-Morning View and the Peach Grove - Moscow - Hammersville tornadoes are circled and magnified.

The total track length  was about 550 miles.

Satellite Loop of March 2, 2012 Tornadoes

March 2, 2012 Satellite Loop (NASA Earth Observatory)

The above video is from the NASA Earth Observatory. It shows the Satellite Loop from the line of supercells that swept through the Midwest, spawning deadly tornadoes on March 2, 2012. You can see the exit region of the jet stream very clearly when the cloud cover begins to form a funnel shape. This is where the tornadoes formed in the warm sector across the Midwest.

The image you see here is the surface analysis of March 2, 2012 at 4:00pm. You can see very clearly the warm sector (the area of mild air) between the cold and the warm front. This warm raising air is one of the many factors acting as fuel which allowing the tornadoes to spin up within their supercells.

The image you see here is a still from the satellite loop video at the top of the page. Just like in the first video, you can see the funnel shape the cloud cover has taken on. This is the exit region of the jet stream, and is where the supercells are located. You can very clearly a few individual supercells at the narrow region of the funnel (cloud patches)

The Tornadoes of March 2, 2012

From Birth to final hours the cells travelled from Missouri into West Virginia. Individual
cells could be identified on radar for more than 550 miles. Times are USA EST (UTC -5 hrs).

The Crittenden-Piner-Morning View EF4 tornado just after touchdown before it struck Piner, KY. Taken from south of Crittenden.

The chaos that ensues with the touchdown of a major tornado or three of them in the case of March 2, 2012 is a heartbreaking testament to the power of Nature. Chaos pretty much says it all, nearly total disorder and the end of daily routines until lives and homes can be rebuilt.

That chaos ripples down to the weather office. Unlike the victims of the storms, for us of course, it is a matter of a minor inconvenience and catching up with tasks put off for storm coverage. This is one of  those tasks.

EF3, 4 and 5 tornadoes are classified as major tornadoes. There was one EF4, two EF3s in the Cincinnati tristate region, 2 - EF2s, 2 - EF1s and 5 - EF0s for a total of 12.

High resolution Doppler radars like the TDWR (Terminal Doppler Weather Radar) often incorrectly called  - Turbulence Detecting Doppler Radar - were located near major airports to detect wind shear, wind shifts and turbulence so aircraft can avoid the dangers associated with these  on takeoff and landing. There is a TDWR in Kenton County south of CVG.

Here is what TCVG,  the Terminal  Doppler Weather Radar near CVG in Kenton County, KY at 4:21:26:57 PM EST (21:26:57 UTC) Friday 2 March 2012.

The well defined hook echo is attenuated by heavy rain at the radar site (blank circle north of the hook). A debris ball is visible near the end of the hook.  Just what is a debris ball? It is parts of houses, trees, peoples memories and prized possesions abducted and pirated away by the 160 mph winds of the EF4 Crittenden-Piner-Fiskburg-Morning View tornado.

Tornadoes With Hook Echoes

Take a look at the 6 radar images below. They are from the EF4 and EF3 tornadoes that struck the  FOX19 viewing area 2 March 2012. The top image is from the Crittenden-Piner-Fiskburg-Morning View tornado, the second is from the Peach Grove-Moscow-Hamersville tornado and the third through sixth are from the Holton, IN tornado.

The supercell that casued the Holton, IN EF3 tornado has no obvious hook at the lowest elevation angle scan on the KIND NEXRAD.

One scan elevation up the hook is visible but not pronounced. The tornado looks to have formed as an RFD inflow jet formed (notice the notch in reflectivity at the tip of the arrow) and began to invade the mesocyclone causing the break in reflectivity southwest of the tornado icon.

The base velocity (slightly wider view than above) shows the inflow jet as a darker shade of pale red flowing into the mesocyclone. Velocities near Westport are typically 20-25 kts. As the air converges and accelerates into the mesocyclone veloities are typically 40 - 50 kts near the tip of the arrow.

GRLevel 2 Analyst display of NROT (normalized rotation at the same scale as the image above). The role of the RFD Inflow Jet is not completely understood but it appears to be an important factor in intensifying the spin of a tornado cyclone by increasing the available air than can be evacuated up through the funnel and by "squeezing" the funnel into a smaller radius thus increasing the rate of spin.

The lesson is that here, 1 EF4 and 2 EF3s touched down. The Holton, IN tornado lacked a well defined hook echo at the lowest elevation scan but at the next higher antenna elevation (.9°) the hook is visible. Using normalized rotation the tornado is evident.

Tornadoes Without Hook Echoes

Now take a look at the Berlin, KY EF0 radar images. The red square dot northwest of Brooksville is the location of the Berlin, KY tornado.

Radar reflectivity of  flanking line thunderstorms entering and moving through northwest Bracken Co. KY at

5:05:15 PM (22:05:15z) March 2, 2012. the black dot west of Brooksville is Berlin, KY and the approximate location

of the brief touchdown of an EF0 tornado. 

This is a leading edge vortex sometimes called a gustnado due to its location along the gust front. These are mostly EF0 and EF1 funnels and many meteorologists feel tornado warnings should NOT be issued for these small, insignificant, short-lived funnels.  

Since 1950, the beginning of the Storm Prediction Center tornado database no one has been killed by an EF0 tornado and only 1 person has been killed by and EF1 tornado in what is now the County Warning Area of NWS Wilmington, OH. This calls into question the wisdom of NWS tornado warning policy which does nothing to distinguish between monster tornadoes and weak, insignificant leading whirlwinds.,

Close up of above, note the "cupping" of the leading edge east of the area of heavy rain in red. The small square dot represents the location of the tornado.

De-aliased velocity display. Because the storms were moving to the northeast at 30 - 40 kts the green everywhere indicates flow towards KILN NEXRAD. The strong lovlevel jet supplies rapidly moving air and induces cyclonic rotation. As it gets lifted over the gustfront and gets pulled into the updraft it is tilted to nearly vertical and is str4etched increasing therate of rotation.

Same as above but with base reflectivity in the background.  The cupping at the leading edge of the moderate to heavy rain (yellow) indicates the circulation creating the leading edge whirlwind.

Normalized rotation from GRLevel2 Analyst.

Close up of above, tornado at small red square dot.

Spectrum width, the range of velocities in a sample volume (specifically the standard deviation of the velocity distribution in a sample volume) is more easily understood as turbulence. 

Close up of the above image. The small square red dot is the location of the tornado. The spectrum width is greatest along the gust front.


The Berlin, KY tornado, an EF0, was a different type of tornado than the EF3s and EF4 which were mesocyclone tornadoes.

Berlin, KY was a leading edge tornado. Leading edge tornadoes are difficult to detect because almost all leading edge vorticies are weak, small and are usually around for only a minute or two, maybe less. They form from air that gains spin outside the thunderstorm. The rotating air is pulled into the thunderstorm and tilted to nearly vertical and can cause a small tornado.

There is mounting evidence from Doppler on Wheels investigations that many large tornadoes may be caused by continual importation of rotation which is tilted to the vertical and stretched by the updraft. Stretching a rotating "tube" of air has the same effect as an ice skater pulling his or her arms towards the body, the rotation is concentrated in a smaller area and the rotation rate increases. When the tube is stretched the diameter shrinks and the rotation rate increases.

Take a look at the images I have produced to explain the importation of rotation:

Development of horizontal rotation from vertical wind shear

Rotation caused by vertical wind shear increases as air streams towards the thunderstorm through the

environment with large vertical shear values.

Wide view of rotation being imported into a thunderstorm. Rotation can be imported over a large area.

An additional source of rotation involves the cold pool that develops under a thunderstorm. As air is lifted up and over the cold pool horizontal rotation is converted to rotation around a vertical axis.

When the rotating tubes of air are tilted to the vertical by the thunderstorm updraft and stretched vertically they can spin up enough to cause a leading edge tornado.

Leading edge tornadoes only live a very short time and the radar signatures are weak so they are much harder to warn for than a mesocyclone tornado.

These elements can also become a significant source of rotation that help maintain large tornadoes as the super cell travels across the landscape.

I'm Back!

It has been a busy year and I have not blogged since March 20, 2012.  With so many projects  going on something had to give and this was it.

Tomorrow, March 2, 2013 is the one-year anniversary of the deadly tornadoes that struck Holton, IN, Crittenden, Piner, Fiskburg and Morning View, KY and  from Peach Grove, KY  to  Moscow, OH  to Hamersville, OH.

I am completing a re-write of my blog entries on those tornadoes with new material for the anniversary. It will all be online by 10 PM Friday March 1.