Thursday, March 8, 2012

Major Severe Outbreak of Early March 2012


In Wake of Morgan County EF-3 Tornado
Aerial Photograph Of West Liberty, Kentucky

West Liberty, Ky., was one of many communities devastated by the greatest tornadoes ever documented in modern times in the foothills and western slopes of the Appalachians ( * ).

*Since 1950 when the best USA tornado record keeping started
( not including tornadoes along and north of the Ohio River or west of the Kentucky foothills ).

[ Since tornado fatality record keeping began in Virginia, during 1916, the deadliest twister to ever strike the Commonwealth remains the monster funnel which devastated Rye Cove in Scott County on May 2, 1929 ( 13 killed ) ].

March 2, 2012 Tornado Outbreak
Multi-Radar & Sensor Indicated Rotational Signatures
 Image Courtesy of National Severe Storms Laboratory

A swarm of rotating supercell thunderstorms tore across the Ohio & Tennessee valleys into western slopes of the Appalachian Mountains during March 2, 2012 ( marking the second outbreak in 3 days ).

March 4, 2008
Warm Sector Setting Just Before Big Stone Gap EF-1

The Big Stone Gap EF-1 tornado represents the more typical type found in the Appalachians, with rapid spin up of often rain-wrapped funnels possessing short damage tracks.

March 2, 2012
West Liberty, Ky., Tornado Video
By lKevinadkins West Liberty EF-3 Tornado

The Great Plains-like nature of tornadoes that ripped a gash into eastern Kentucky foothill terrain was in part driven by extreme shear which tilted the supercells in such a way to keep their spinning updrafts separated from downdrafts.

[ This updaft-downdraft separation allowed the supercells to be long-lived, with amazing on ground tornado tracks, by keeping low energy downdraft air away from their inflow.  It also allowed the occasionally 1 mile WIDE funnels to be clearly visible and isolated from falling rain and hail ( like many on the Plains ) ].

( Updated But Still Preliminary )
Eastern Kentucky Tornado Tracks - March 2, 2012
Courtesy of the Jackson, Ky., NWS Forecast Office

The West Liberty tornado was on the ground for an incredible 86 miles, with an adjacent EF-3 that traveled 49 miles along a path which devastated the Salyersville community in Magoffin County.

[ A deadly EF-4 rated tornado was also on the ground for 49 miles across southern Indiana, as surveyed by the Louisville, Ky., NWS Forecast Office ].

( Updated: March 23, 2012 )
The Kentucky death toll from this March 2 tornado outbreak reached 24 with loss of a Laurel County woman ( 37-year old Mary A. Pruitt ) on March 23, according to the Lexington Herald-Leader.

March 2, 2012
Tornado Track In Lee & Claiborne Counties

Two confirmed tornadoes impacted rolling, open expanses of the Powell River Valley, amid southwest portions of the High Knob Landform, with EF-1 and EF-2 rated areas of damage surveyed in southern Lee County and northern Claiborne County along the VA-TN stateline.

[ Note that photographs submitted by Melissa Mullins revealed another area of concentrated damage in the Jonesville area of
Lee County ].

( Updated - March 9, 2012 )
An EF-1 tornado was found to have caused the damage reported by Melissa Mullins some 3 miles SE of Jonesville, in Lee County, to mark the third official tornado to have occurred amid this episode in the High Knob Landform & Cumberland Block.

March 2, 2012
Tornado Track SE of Jonesville In Lee County


( Specific Atmospheric Details )
Severe Thunderstorm Outbreak
of March 2, 2012

This severe weather outbreak was predicted well in advance of the first thunderstorms, with the Storm Prediction Center in Norman, Ok., issuing a rare moderate risk across a large portion of the Ohio and Tennessee valleys.

[ Rare for early March in this section of the USA where cold weather and snow are more likely ( much of the moderate risk region was later upgraded to a HIGH RISK prior to the main event in afternoon hours of March 2 ) ]. 

1:45 AM - March 2, 2012
Doppler Radar-Precipitable Water-SPC Risk Regions

A dry air mass covered much of the moderate risk region of the Storm Prediction Center ( SPC ) at 1:45 AM March 2, with significant temperature drops generated in mountain valleys.

Most Unstalbe CAPE at 7:00 AM - March 2, 2012

Temperatures early on March 2 were below freezing in the City of Norton and in Clintwood, such that formation of active storms after sunrise took many by surprise!

However, in fact, supercell thunderstorms are actually relatively common in elevated settings when there is significant upstream CAPE and streamwise vorticity amid a warm air advection and moisture transport regime.

[ Note on the above graphic that MUCAPE ( Most Unstable Convective Available Potential Energy ) values of 1000-2000 J/kg were upstream of southwestern Virginia amid a developing warm air advection and moisture transport pattern ( below ) ].

Most Unstalbe CAPE at 9:00 AM - March 2, 2012

[ Note on the above graphic that the Lifted Parcel Level ( LPL ) was more than 1000 meters across Wise, Scott, and Lee counties to indicate that CAPE was elevated in nature above a chilly, stable boundary layer above which supercell development began ].

9:00 AM - March 2, 2012
850 MB Moisture Transport & Vector Magnitudes

Elevated convection developing above decoupled boundary layers can be benign if upstream CAPE and streamwise vorticity are weak. One of the best parameters to help determine this is the Effective Storm Relative Helicity ( ESRH ), not shown for this hour, which tends to confine storm relative helicity to that portion of the atmosphere in which air parcels are buoyant and not strongly capped.

Storm Prediction Center PDF
Richard Thompson, Roger Edwards, Corey Mead

9:00 AM - March 2, 2012
Mean Sea Level Pressure & Doppler Composite

[ An already strong surface low over Missouri at 1400z was tightening the regional pressure gradient as it began lifting northeast toward Lake Huron with rapid deepening by 1200z March 3 ( i.e., core pressure drops in the bombogenesis realm ) ].

While showers with local downpours developed by around sunrise it was mid-morning into mid-day when booming storms on the Virginia side of the stateline intensified to strong-severe levels.


Doppler Base Reflectivity
Slide Show of Elevated Convection
( 10:16 AM to 2:08 PM )

The following can be looked at as individual frames or clicked through in the picture viewer to generate a moving loop over time ( applies to all slide shows ).

Doppler Base Reflectivity at 10:16 AM - March 2, 2012

Doppler Base Reflectivity at 10:21 AM - March 2, 2012

Doppler Base Reflectivity at 10:25 AM - March 2, 2012 

Doppler Base Reflectivity at 10:29 AM - March 2, 2012

Doppler Base Reflectivity at 10:33 AM - March 2, 2012

Doppler Base Reflectivity at 10:37 AM - March 2, 2012

Doppler Base Reflectivity at 10:42 AM - March 2, 2012

Doppler Base Reflectivity at 10:50 AM - March 2, 2012

Doppler Base Reflectivity at 10:55 AM - March 2, 2012

Doppler Base Reflectivity at 10:59 AM - March 2, 2012

[ Note the thunderstorm moving across the VA-TN border into southern Scott County, Va., became a significant hail producer over Gate City.  While many elevated storms do not produce large hail they can generate large quantities of hail, as this storm did to cover the ground & roads ( beneath its high reflectivity core ) ].

Doppler Base Reflectivity at 11:03 AM - March 2, 2012

Doppler Base Reflectivity at 11:08 AM - March 2, 2012

Doppler Base Reflectivity at 11:12 AM - March 2, 2012

Doppler Base Reflectivity at 11:20 AM - March 2, 2012

Doppler Base Reflectivity at 11:29 AM - March 2, 2012

Doppler Base Reflectivity at 11:33 AM - March 2, 2012

Doppler Base Reflectivity at 11:43 AM - March 2, 2012

This marked the end of the first main wave of elevated convection, with a second wave rapidly forming by 12:17 PM.

Doppler Base Reflectivity at 12:17 PM - March 2, 2012

Doppler Base Reflectivity at 12:25 PM - March 2, 2012

Doppler Base Reflectivity at 12:34 PM - March 2, 2012

Doppler Base Reflectivity at 12:38 PM - March 2, 2012

Doppler Base Reflectivity at 12:46 PM - March 2, 2012

Doppler Base Reflectivity at 12:51 PM - March 2, 2012

Doppler Base Reflectivity at 12:59 PM - March 2, 2012

Doppler Base Reflectivity at 1:08 PM - March 2, 2012

Doppler Base Reflectivity at 1:16 PM - March 2, 2012

Doppler Base Reflectivity at 1:20 PM - March 2, 2012

Doppler Base Reflectivity at 1:25 PM - March 2, 2012

Doppler Base Reflectivity at 1:29 PM - March 2, 2012

Doppler Base Reflectivity at 1:39 PM - March 2, 2012

Doppler Base Reflectivity at 1:47 PM - March 2, 2012

Doppler Base Reflectivity at 1:56 PM - March 2, 2012

Doppler Base Reflectivity at 2:08 PM - March 2, 2012

A final batch of showers & embedded downpours forming over Wise, Scott, and Lee counties at 2:08 PM marked the end of this elevated convective period ( with attention now shifting west ).

[ While every single tornado that impacted any life was significant during this outbreak, the following slide shows will document atmospheric conditions during the main event time leading up to eastern Kentucky EF-3 tornadoes ( with a specific focus upon the West Liberty EF-3 around 2300 UTC ) ].


Major Tornado Outbreak
The Main Event

USA Water Vapor Satellite Image At 2:45 PM - March 2, 2012

Many important ingredients were clearly present on early afternoon water vapor imagery, with a distinct V-shaped divergence signature associated with explosive convective development seen ahead of a cold pocket pushing into mid-level drying.

Being early March this was an anomalous setting in which there was a steady, eastward shift of best thermodynamics ahead of supercell development, as low-levels that were cool and stable gave way to conditions capable of supporting surface based storms ( helicity and other parameters to follow ).

[ Surface based thunderstorms became most widespread across western-central portions of the warm sector into the afternoon, as eastern portions struggled to recover from stable surface conditions and elevated morning to early afternoon convective activity ].

This process was signaled by positive 3-hour changes in Theta-E, with max changes occurring ahead of monster supercell initiation and storm propagation.


Slide Show Of Theta-E Changes
And Composite Doppler Reflectivity
( 1500z to 2300z on March 2, 2012 )

Equivalent Potential Temperature ( Theta-E ) increases over time show where the atmosphere is becoming more buoyant, with the positive changes occurring as a result of increases in temperature and/or moisture ( in this case with increases in both ). 

10:00 AM ( 1500z ) - March 2, 2012
Composite Doppler and 3-Hour Theta-E Change

11:00 AM ( 1600z ) - March 2, 2012
Composite Doppler and 3-Hour Theta-E Change

12:00 AM ( 1700z ) - March 2, 2012
Composite Doppler and 3-Hour Theta-E Change

[ In this case MAX changes in Theta-E over southern Illinois & Indiana into western Kentucky indicated in advance where the strongest supercells developed, with these max changes moving ahead of the convection into eastern Kentucky and zeroing in on the area around West Liberty and Salyersville by 2100-2200z ].

1:00 PM ( 1800z ) - March 2, 2012
Composite Doppler and 3-Hour Theta-E Change

2:00 PM ( 1900z ) - March 2, 2012
Composite Doppler and 3-Hour Theta-E Change

3:00 PM ( 2000z ) - March 2, 2012
Composite Doppler and 3-Hour Theta-E Change

4:00 PM ( 2100z ) - March 2, 2012
Composite Doppler and 3-Hour Theta-E Change

5:00 PM ( 2200z ) - March 2, 2012
Composite Doppler and 3-Hour Theta-E Change

6:00 PM ( 2300z ) - March 2, 2012
Composite Doppler and 3-Hour Theta-E Change



Slide Show of 850 MB Moisture Transport
 ( Supplying Energy for Storm Development )

10:00 AM ( 1500z ) - March 2, 2012
850 MB Moisture Transport & Vector Magnitudes

At 1500z the strongest 850 MB transport of richest moisture was feeding into convection of the warm advection regime from Tennessee & Kentucky into the local mountains, as highlighted by the previous Doppler slide show ( * ).

*Locally severe elevated storms in warm advection were also occurring well north and west of the mountains early in the day, as noted by the SPC Day 1 Discussions later in this section.

The elevated convective focus presented above being upon the local mountains ( this is the High Knob Landform website which typically has a local focus, however, the historic nature of this event demands a broader perspective ).

1:00 PM ( 1800z ) - March 2, 2012
850 MB Moisture Transport & Vector Magnitudes

During the afternoon strong 850 MB transport expanded across the warm sector and HIGH RISK region of the SPC, driven in part by the increasing surface-850 MB convergence along & ahead of a strong cold front acting as a low-level lifting mechanism triggering the main band of convection.

2:00 PM ( 1900z ) - March 2, 2012
850 MB Moisture Transport & Vector Magnitudes

3:00 PM ( 2000z ) - March 2, 2012
850 MB Moisture Transport & Vector Magnitudes

4:00 PM ( 2100z ) - March 2, 2012
850 MB Moisture Transport & Vector Magnitudes

5:00 PM ( 2200z ) - March 2, 2012
850 MB Moisture Transport & Vector Magnitudes

6:00 PM ( 2300z ) - March 2, 2012
850 MB Moisture Transport & Vector Magnitudes

Slide shows above give a very basic view of some thermodynamics, with a more detailed analysis below looking into some of the reasons why the SPC correctly upgraded to a rare HIGH risk prior to the main event.


SPC Changes In Risk Regions
( From Moderate to HIGH )

SPC Day 1 Outlook At 0542z - March 2, 2012

SPC Day 1 Update At 1630z - March 2, 2012

SPC Day 1 Tornado Probability At 0532z - March 2, 2012

SPC Updated Tornado Probability 1630z - March 2, 2012

SPC Day 1 Discussion 0542z - March 2, 2012

SPC Updated Discussion 1630z - March 2, 2012



Mesoscale Analysis
Afternoon Conditions
( March 2, 2012 )

Analysis reveals that surface based instability by 2000 UTC had greatly increased from southern Indiana into western-central portions of Kentucky, amid extreme wind shear, with much more surface stability over northeastern Kentucky.

[ Note that the following slide shows begin around the time of the Henryville, Indiana EF-4 and end at the time of the West Liberty, Ky., EF-3 over Morgan County ].


Slide Show of Surface Based CAPE
+ Surface Based Convective Inhibition

3:00 PM ( 2000z ) - March 2, 2012
SB CAPE & SB CIN + Surface Winds & Reflectivity

4:00 PM ( 2100z ) - March 2, 2012
SB CAPE & SB CIN + Surface Winds & Reflectivity

Observe that significant surface based CAPE values were collapsing southeastward and dropping over time in advance of approaching surface-850 MB troughs and lowering late afternoon sun angles.

5:00 PM ( 2200z ) - March 2, 2012
SB CAPE & SB CIN + Surface Winds & Reflectivity

6:00 PM ( 2300z ) - March 2, 2012
SB CAPE & SB CIN + Surface Winds & Reflectivity


Slide Show of Most Unstable CAPE
and Lifted Parcel Levels

3:00 PM ( 2000z ) - March 2, 2012
MUCAPE + Lifted Parcel Levels & Doppler Reflectivity

Reference the SPC for more information on CAPE and MUCAPE, with values in this case being on the low end for significant tornado potential.

Rich Thompson

4:00 PM ( 2100z ) - March 2, 2012
MUCAPE + Lifted Parcel Levels & Doppler Reflectivity

5:00 PM ( 2200z ) - March 2, 2012
MUCAPE + Lifted Parcel Levels & Doppler Reflectivity

MUCAPE charts show the Henryville, Indiana EF-4 formed in an atmosphere having moderate Convective Available Potential Energy that was surface based, with eastward propagation of the supercells into an environment where the most unstable CAPE remained elevated 750 to 1000 meters above ground level over West Liberty, Ky., at 2300z ( dropping from over 1000 meters at 2000z ).

6:00 PM ( 2300z ) - March 2, 2012
MUCAPE + Lifted Parcel Levels & Doppler Reflectivity


Slide Show of Energy Helicity Index
( 0-1 KM Using Mixed Layer CAPE )

Generalized EHI Value Guide:

EHI = 1
Tornadoes Possible

EHI = 1 to 2
Moderate to Strong Tornadoes Possible

EHI > 2
Significant Tornadoes Possible


EHI = CAPE x Storm Relative Helicity
160,000


3:00 PM ( 2000z ) - March 2, 2012
Surface to 1 KM EHI & Doppler Base Reflecitivty

4:00 PM ( 2100z ) - March 2, 2012
Surface to 1 KM EHI & Doppler Base Reflecitivty

5:00 PM ( 2200z ) - March 2, 2012
Surface to 1 KM EHI & Doppler Base Reflecitivty

6:00 PM ( 2300z ) - March 2, 2012
Surface to 1 KM EHI & Doppler Base Reflecitivty

These charts show exceptional EHI values in place over the SPC HIGH RISK region with an east to southeast propagation of the highest EHI into the Cumberland Plateau & Cumberland Mountains 
( including Lee County, VA ) by 2300 UTC.


Slide Show of Energy Helicity Index
( 0-3 KM Using Mixed Layer CAPE )

3:00 PM ( 2000z ) - March 2, 2012
Surface to 3 KM EHI & Doppler Base Reflecitivty

4:00 PM ( 2100z ) - March 2, 2012
Surface to 3 KM EHI & Doppler Base Reflecitivty

5:00 PM ( 2200z ) - March 2, 2012
Surface to 3 KM EHI & Doppler Base Reflecitivty

6:00 PM ( 2300z ) - March 2, 2012
Surface to 3 KM EHI & Doppler Base Reflecitivty

Given the SB CAPE and MUCAPE charts already highlighted it is clear that these exceptional EHI values are being driven by extreme storm relative helicity, so lets take a closer look at this aspect.

[ Note that the following two slide shows extend through the evening hours of March 2 to also include the time period of Claiborne County, Tn., and Lee County, Va., tornadoes ].


Slide Show of Storm Relative Helicity
( 0 to 3 KM and Storm Motion Vectors )


Generalized SRH Value Guide:

SRH = 150 to 299
Supercells Possible with Weak Tornadoes

SRH > 250
Increasing Threat of Tornadoes

SRH = 300 to 499
Very Favorable for Supercells & Strong Tornadoes

SRH > 450
Violent Tornadoes Possible


4:30 PM ( 2130z ) - March 2, 2012
0-3 KM Storm Relative Helicity & Storm Motion

5:00 PM ( 2200z ) - March 2, 2012
0-3 KM Storm Relative Helicity & Storm Motion

At 2300z the 1250 m2/s2 value of SRH over West Liberty, Ky., was three times what was needed to have violent tornadoes!

6:00 PM ( 2300z ) - March 2, 2012
0-3 KM Storm Relative Helicity & Storm Motion

7:00 PM ( 0000z March 3 ) - March 2, 2012
0-3 KM Storm Relative Helicity & Storm Motion

8:00 PM ( 0100z March 3 ) - March 2, 2012
0-3 KM Storm Relative Helicity & Storm Motion

9:00 PM ( 0200z March 3 ) - March 2, 2012
0-3 KM Storm Relative Helicity & Storm Motion

10:00 PM ( 0300z March 3 ) - March 2, 2012
0-3 KM Storm Relative Helicity & Storm Motion


Slide Show
Effective Storm Relative Helicity - ESRH
( Including Effective Inflow Base & Storm Motion )

4:30 PM ( 2130z ) - March 2, 2012
Effective SRH & Inflow Base With Storm Motion Vectors

5:00 PM ( 2200z ) - March 2, 2012
Effective SRH & Inflow Base With Storm Motion Vectors

Since the Most Unstable CAPE at 2300z over West Liberty, Ky., was shown to be elevated well above ground level, Effective SRH should be looked at to see what value it gives for helicity relative to the storm.

6:00 PM ( 2300z ) - March 2, 2012
Effective SRH & Inflow Base With Storm Motion Vectors

At 2300z the Morgan County EF-3 is amid a tight ESRH gradient that is advecting along with the supercells, with values between 200-900 m2/s2 that jump to 1000 m2/s2 by 0000z ( 7 PM local time ).

Outrageous values!

No wonder EF-3 tornado paths which devastated West Liberty, Salyersville, and many other places in both Kentucky and western West Virginia were so long-tracked and wide.

[ The concept being analogous to spinning a top, the faster you spin it the longer it takes to wind down, which in a simplistic way explains part of the reason why these were such long-track tornadoes ].

7:00 PM ( 0000z March 3 ) - March 2, 2012
Effective SRH & Inflow Base With Storm Motion Vectors

It was also during this time that a supercell with a Doppler indicated hook echo & TVS signature had prompted tornado warnings for Bell and Harlan counties in southeast Kentucky and Wise County in southwestern Virginia ( detailed in later section ).

8:00 PM ( 0100z March 3 ) - March 2, 2012
Effective SRH & Inflow Base With Storm Motion Vectors

9:00 PM ( 0200z March 3 ) - March 2, 2012
Effective SRH & Inflow Base With Storm Motion Vectors

10:00 PM ( 0300z March 3 ) - March 2, 2012
Effective SRH & Inflow Base With Storm Motion Vectors

For more information reference:

RICHARD L. THOMPSON, COREY M. MEAD, AND ROGER EDWARDS



Slide Show of Effective Bulk Shear
 ( 6:00 PM to 10 PM Local Time )


Generalized Guide:

Effective Bulk Shear = 25 to 40+ knots
Supercells Become Increasingly Likely


6:00 PM ( 2300z ) - March 2, 2012
Effective Bulk Wind Shear Vector ( Knots )

7:00 PM ( 0000z March 3 ) - March 2, 2012
Effective Bulk Wind Shear Vector ( Knots )

8:00 PM ( 0100z March 3 ) - March 2, 2012
Effective Bulk Wind Shear Vector ( Knots )

9:00 ( 0200z March 3 ) - March 2, 2012
Effective Bulk Wind Shear Vector ( Knots )

10:00 PM ( 0300z March 3 ) - March 2, 2012
Effective Bulk Wind Shear Vector ( Knots )


Afternoon Changes On 
NASA Visible Imagery

NASA Visible At 1710z ( 12:10 PM ) - March 2, 2012

Extensive mid-day cloudiness gave way to notable breaks in the overcast west of the Appalachians and High Knob Landform into early afternoon.

NASA Visible At 1925z ( 2:25 PM ) - March 2, 2012

NASA Visible At 1940z ( 2:40 PM ) - March 2, 2012

NASA Visible At 2025z ( 3:25 PM ) - March 2, 2012

Towering tops of supercell thunderstorms were illuminated by low sun angles in late afternoon, complete with rippling gravity waves.

NASA Visible At 2125z ( 4:25 PM ) - March 2, 2012

NASA Visible At 2210z ( 5:10 PM ) - March 2, 2012

NASA Visible At 2240z ( 5:40 PM ) - March 2, 2012



Focus Upon The West Liberty
EF-3 Tornado - 5:58 PM
( March 2, 2012 )

Family's Surveillance Cameras Catch Tornado
Video Courtesy of YouTube

A home security system with 7 different camera angles caught the West Liberty, Ky., EF-3 as it passed by.  One must note that this home did not take a direct hit but was close with tremendous inflow noted into the tornado.

[ There is no sound on this video.  The funnel of the tornado can be seen in upper right corner during the 0:57-1:15 time period.  A direct hit would not have left the car sitting upright, or the house most likely, and this video probably would have been lost ].

6:00 PM ( 2300z ) - March 2, 2012
Theta-E Ridge ( Axis of Available Potential Energy )

Although CAPE values were relatively low during this event, supercells fired within and propagated along with a Theta-E ridge and more than made up for limitations of thermodynamics with very strong fluid dynamics ( especially in northeastern Kentucky ).

6:00 PM ( 2300z ) - March 2, 2012
Jet Stream Level Divergence At 300 MB

Low-level convergence was aided by upper-level divergence and splitting of high altitude jet stream wind fields, allowing the tilted supercells plenty of room for growth as air was exhausted out their tops like in a chimney.

6:00 PM ( 2300z ) - March 2, 2012
850 MB to 500 MB Wind Crossover Angles

While the helicity vector component of speed shear was greatest in magnitude, the directional portion was not trivial with significant veering of vertical wind profiles from SE-SSE at the surface to SSW-WSW aloft.

Terrain Surrounding West Liberty, Kentucky

Since most hills around West Liberty are below 1200 feet above sea level and only 200 to 400 feet taller than valley floors the effective inflow base and lifted parcel levels were elevated enough that terrain likely had little impact upon inflow with the separation of the rotating updraft from downdrafts, due in part to storm tilt, combining to generate a Great Plains tornado setting amid the Appalachian foothills.

[ Just over 15 air miles to the southeast this same type of horror played out for residents of Salyersville, Ky., in Magoffin County.  While these communities are highlighted, many were impacted by a combined on the ground path of 135 miles for just these two tornadoes ( as surveyed by NWS Forecast Offices in Jackson, Ky., and Charleston, Wv. ) ].

6:00 PM ( 2300z ) - March 2, 2012
Current Lifted Parcel Levels & 3 Hour MUCAPE Change


Doppler Radar Base Reflectivity
Slide Show of West Liberty EF-3
( Frames Centered At Huntington, West Virginia )

A classic tornadic supercell presentation was displayed by this storm with V-shaped divergence and a tremendous hook that upon tearing through West Liberty took on the appearance of a ball of debris ( some of which would be carried more than 90 air miles and dropped upon the state capitol of West Virginia in Charleston. Simply incredible! ).

Storm Statistics from JKL NWSFO

EVENT DATE: MARCH 2 2012 
EVENT TYPE: EF-3
 TORNADO ESTIMATED PEAK WINDS: 140 MPH 
INJURIES/FATALITIES: 
2 FATALITIES IN MENIFEE COUNTY 
6 FATALITIES IN MORGAN COUNTY
 EVENT START TIME/LOCATION: 539 PM EST AT 37.905022N/83.614639W 
EVENT END TIME/LOCATION: 618 PM EST AT 37.9921N/82.9198W 
DAMAGE PATH LENGTH:  APPROX 86 MILES TOTAL
( 60 MILES IN KENTUCKY & 26 MILES IN WEST VIRGINIA
DAMAGE WIDTH: MAXIMUM 1 MILE WIDTH

*EVENT END TIME IN THE NWS JACKSON KY FORECAST AREA.

2247z - March 2, 2012
Doppler Radar Base Reflectivity at 5:47 PM

2252z - March 2, 2012
Doppler Radar Base Reflectivity at 5:52 PM

2256z - March 2, 2012
Doppler Radar Base Reflectivity at 5:56 PM

2301z - March 2, 2012
Doppler Radar Base Reflectivity at 6:01 PM

2305z - March 2, 2012
Doppler Radar Base Reflectivity at 6:05 PM

2310z - March 2, 2012
Doppler Radar Base Reflectivity at 6:10 PM

[ Note another supercell with a distinctive hook coming into view northwest of the West Liberty EF-3 was an EF-1 tornado producer in Bath County, Kentucky ].

2314z - March 2, 2012
Doppler Radar Base Reflectivity at 6:14 PM 

2319z - March 2, 2012
Doppler Radar Base Reflectivity at 6:19 PM 

2324z - March 2, 2012
Doppler Radar Base Reflectivity at 6:24 PM 

2328z - March 2, 2012
Doppler Radar Base Reflectivity at 6:28 PM 

Chief meteorologist Tony Cavalier, of WSAZ-TV in Huntington, Wv., writes about his emotional visits to Morgan & Lawrence counties in wake of this destructive and historic Kentucky tornado.

Meteorologist Tony Cavalier ( WSAZ-TV )

Killer Tornado Part II - Lawrence County




Doppler Radar Base Reflectivity
Slide Show of Salyersville EF-3
( Frames Centered At Pikeville, Kentucky )

Another classic supercell developed just southeast of the West Liberty storm track with a devastating strike on Salyersville, Ky., just after 7:00 PM.  It also formed a tremendous hook.

Storm Statistics from JKL NWSFO

EVENT DATE: MARCH 2, 2012
EVENT TYPE: EF-3
TORNADO ESTIMATED PEAK WINDS: 160 MPH 
INJURIES/FATALITIES: 2 FATALITIES IN JOHNSON COUNTY
EVENT START TIME/LOCATION: 650 EST AT 37.703883N/83.2728W 
EVENT END TIME/LOCATION: 738 PM EST AT 37.832617N/82.403883W 
DAMAGE PATH LENGTH: 49 MILES IN TOTAL
( 48 MILES IN KENTUCKY & 1 MILE IN WEST VIRGINIA )      
DAMAGE WIDTH: MAXIMUM WIDTH 0.75 MILES

*EVENT END TIME IN THE NWS JACKSON KY FORECAST AREA

2347z - March 2, 2012
Doppler Radar Base Reflectivity at 6:47 PM

2351z - March 2, 2012
Doppler Radar Base Reflectivity at 6:51 PM

2356z - March 2, 2012
Doppler Radar Base Reflectivity at 6:56 PM

( 0001z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 7:01 PM

( 0005z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 7:05 PM

( 0010z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 7:10 PM

( 0014z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 7:14 PM

( 0019z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 7:19 PM

( 0024z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 7:24 PM

( 0028z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 7:28 PM

( 0033z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 7:33 PM

( 0037z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 7:37 PM

[ NOTE:  It takes time to pick out these individual frames for a slide show presentation so I have only included Base Reflectivity and not Velocities.  For a loop of base velocities ( showing RED-GREEN couplets, reference the following NEXRAD loops which can also be found on YouTube ].


Nexrad Level II LOOPS
Base Reflectivity & Base Velocity
( West Liberty & Salyersville Tornadoes )


For more details please reference:






Monster Supercell Threatens
The Cumberland Overthrust Block

As tornadic supercells were ravaging northeastern Kentucky a new thunderstorm developed and moved across the I-75 corridor into mountains of the Cumberland Block.

[ This rapidly developed into a high reflectivity supercell with a hail core and TVS signature on Doppler that formed a notable hook by around 2330z ( 6:30 PM ) ].

2310z - March 2, 2012
Doppler Radar Base Reflectivity at 6:10 PM

2319z - March 2, 2012
Doppler Radar Base Reflectivity at 6:19 PM

2328z - March 2, 2012
Doppler Radar Base Reflectivity at 6:28 PM

2337z - March 2, 2012
Doppler Radar Base Reflectivity at 6:37 PM

2347z - March 2, 2012
Doppler Radar Base Reflectivity at 6:47 PM

This supercell was moving into an atmosphere with greater available potential energy but less total storm relative helicity ( but very significant in this setting ) than supercells over northeast Kentucky, thus the surface to 3 km Energy Helicity Index on this storm was higher as CAPE added more to its total value ( reference previous EHI definition ).

7:00 PM ( 0000z March 3 ) - March 2, 2012
Surface to 1 KM Storm Relative Helicity & Storm Motion

7:00 PM ( 0000z March 3 ) - March 2, 2012
Mean Sea Level Pressure & Surface Wind Pattern

This supercell was isolated out by itself in advance of the surface cold front with excellent inflow of moist, relatively high energy and highly sheared air.

The Bottom Line...
This was a very worrisome storm given the terrible destruction ongoing to the north!



Doppler Radar Reflectivity
Slide Show of Storm Evolution
( 6:51 PM to 8:01 PM )

2351z - March 2, 2012
Doppler Radar Base Reflectivity at 6:51 PM

2356z - March 2, 2012
Doppler Radar Base Reflectivity at 6:56 PM

Hail of 2.00" to 2.75" in diameter was reported with the supercell as it passed over the Lenarve and Grays Knob communities in Harlan County, Ky., with trees downed in the Putney area.

( 0001z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 7:01 PM

( 0005z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 7:05 PM

This supercell underwent a dramatic change in structure upon reaching the Virginia-Kentucky border during the 0010-0020z period to suggest orographics and frictional drag became significant factors in its propagation and intensity across the Black Mountain-High Knob Massif corridor.

( 0010z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 7:10 PM

( 0014z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 7:14 PM

( 0019z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 7:19 PM

( 0024z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 7:24 PM

( 0028z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 7:28 PM

( 0033z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 7:33 PM

[ This was a very powerful storm even at its far northern periphery where ROARING outflow was observed in Clintwood as its core passed well to the south along northern slopes of the High Knob Massif into southern Wise & Dickenson counties ].

( 0037z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 7:37 PM

( 0043z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 7:43 PM

( 0048z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 7:48 PM

( 0052z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 7:52 PM

( 0057z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 7:57 PM

( 0101z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 8:01 PM

The section where this supercell began to change is shown below, with 3000 to 4000+ feet mountain ridges and sprawling highcountry that is dramatically different from the foothill terrain of northeastern Kentucky.

( Dramatically Different Terrain From NE Kentucky )
Black Mountain - Upper High Knob Landform Corridor
Terrain Map Courtesy of Google

The upper portion of the High Knob Landform includes its remnant massif of highcountry, a portion of which is visible above, and its Little Stone Mountain arm, the Powell Valley of Wise County, the upper part of the Powell River Valley, and the northwestern & southeastern mountain flanks of its extended landform that rest adjacent to the Black Mountains.

While there is no place completely safe from a destructive tornado, odds are excellent that IF the above supercell had not run across lofty mountain terrain that it would have become another long-track, violent tornado producer given atmospheric conditions present and the activity ongoing at that time northwest of the mountains!



EF-1 & EF-2 Tornadoes
Evening of March 2, 2012
( Claiborne County, Tn., and Lee County, Va. )


Storm Statistics from MRX NWSFO
March 2, 2012 Tornado Outbreak

HARROGATE, TN
EVENT DATE: MARCH 2, 2012
EVENT TYPE: EF-2
TORNADO ESTIMATED PEAK WINDS: 120 MPH 
EVENT TIME: 829 PM 
DAMAGE PATH LENGTH: 2.7 MILES IN TOTAL     
DAMAGE WIDTH: 250 YARDS

EWING, VA
EVENT DATE: MARCH 2, 2012
EVENT TYPE: EF-1
TORNADO ESTIMATED PEAK WINDS: 110 MPH 
EVENT TIME: 842 PM 
DAMAGE PATH LENGTH: 4.8 MILES IN TOTAL     
DAMAGE WIDTH: 200 YARDS

JONESVILLE, VA
EVENT DATE: MARCH 2, 2012
EVENT TYPE: EF-1
TORNADO ESTIMATED PEAK WINDS: 95 MPH 
EVENT TIME: 910 PM 
DAMAGE PATH LENGTH: 1.0 MILE IN TOTAL     
DAMAGE WIDTH: 100 YARDS


Reference above graphics for this period:
Effective Storm Relative Helicity
Effective Bulk Shear Vectors
0-3 KM Storm Relative Helicity

High values of effective SRH and bulk shear dropped significantly during the 8:00 to 10:00 PM period of March 2, but not before several more tornadoes formed.

8:00 PM ( 0100z March 3 ) March 2, 2012
Surface to 1 KM Storm Relative Helicity & Storm Motion

9:00 PM ( 0200z March 3 ) - March 2, 2012
Surface to 1 KM Storm Relative Helicity & Storm Motion

Extreme values of 0-1 km storm relative helicity, suggestive of more than enough for violent tornadoes, are modified some by ESRH with its constraints on CAPE & CIN ( refer to previous slide show ).

However, values over western Lee and Claiborne counties remained very high into the 8:00 to 9:00 PM period with a notable increase in upper level divergence shown on 300 MB jet stream charts.

8:00 PM ( 0100z March 3 ) - March 2, 2012
300 MB Height - Divergence - Wind Vectors

9:00 PM ( 0200z March 3 ) - March 2, 2012
300 MB Height - Divergence - Wind Vectors

8:00 PM ( 0100z March 3 ) - March 2, 2012
Mean Sea Level Pressure & Surface Wind Vectors

9:00 PM ( 0200z March 3 ) - March 2, 2012
Mean Sea Level Pressure & Surface Wind Vectors

A drop in supercell and tornado parameters after 9:00 PM along the surface-850 mb troughs did not eradicate severe threats as a line echo wave pattern took shape with activity pushing across the High Knob Landform and western Appalachians into the Great Valley.

10:00 PM ( 0300z March 3 ) - March 2, 2012
Mean Sea Level Pressure & Surface Wind Vectors



Doppler Radar Reflectivity
Slide Show of Evening Activity
( Frames Centered At Jacksboro, Tennessee )

( 0115z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 8:15 PM

( 0120z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 8:20 PM

( 0125z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 8:25 PM

At the time of the Harrogate EF-2 there was a TVS and red-green couplet on storm relative mean radial velocity scans ( not shown ) but no more than a weak echo region on the base reflectivity below, in dramatic contrast to earlier supercells with major hooks.

[ Signs that the atmosphere was changing back toward the more typical, rain-wrapped and much shorter lived and track tornadoes of the Appalachians ( climatological mean type ) ].

( 0129z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 8:29 PM

( 0134z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 8:34 PM

( 0138z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 8:38 PM


Doppler Radar Reflectivity
Slide Show of Evening Activity
( Frames Centered At Wise, Virginia )

A large rounded supercell centered over the Powell River Valley of western Lee County was observed on Doppler at the time of the Ewing EF-1 tornado, with broken but developing line segments to the northwest near the western edge of the mountains.

( 0143z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 8:43 PM 

( 0148z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 8:48 PM 

( 0152z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 8:52 PM 

( 0157z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 8:57 PM 

( 0201z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 9:01 PM 

( 0206z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 9:06 PM  

( 0211z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 9:11 PM  

( 0215z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 9:15 PM  

( 0220z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 9:20 PM  

( 0225z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 9:25 PM  

( 0229z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 9:29 PM  

( 0234z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 9:34 PM  

( 0238z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 9:38 PM  

( 0244z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 9:44 PM  

( 0249z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 9:49 PM  


Line Echo Wave Pattern 
( LEWP ) Formation

Beyond the 9:10 PM time of the final EF-1 tornado just southeast of Jonesville in Lee County, Va., a trend toward wavy line formation occurred with LEWP taking shape along and just east of the western front range of the mountains. 

( 0253z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 9:53 PM  

( 0253z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 9:53 PM   

( 0253z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 9:53 PM   

A major bow in the line developed just leeward of the High Knob Massif in a climatologically favored zone of formation documented many times in the past as squall lines pass lee of the massif.

( 0258z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 9:58 PM   

( 0302z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 10:02 PM   

( 0307z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 10:07 PM   

( 0312z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 10:12 PM   

( 0316z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 10:16 PM 

( 0321z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 10:21 PM 

( 0325z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 10:25 PM 

( 0330z March 3 ) - March 2, 2012
Doppler Radar Base Reflectivity at 10:30 PM 

Finally, this terrible day was ending!


Heavy Rainfall Totals
( February 29 to March 3, 2012 )

Active storms with an initial outbreak of severe weather during February 29 combined with this event to generate 3.00" to 4.00"+ rainfall totals across the High Knob Landform, from the City of Norton and High Knob Massif southwest through Lee County & Cumberland Gap National Park.

Ending At 2:57 AM ( 0757z ) March 1, 2012
Doppler Storm Rainfall Totals For First Event

Ending At 12:26 AM ( 0526z ) March 3, 2012
Doppler Storm Rainfall Totals For Second Event

Minor flooding was reported in:
Big Stone Gap
East Stone Gap
City of Norton
Tacoma
Coeburn
( Parts of Lee & Scott counties )

USGS river gages featured significant rises during this stormy period.

Powell River At Big Stone Gap In Wise County

The first peak was in the wake of rain and snow melt following the heavy snowfall of February 19.


Powell River Near Jonesville In Lee County

Clinch River At Speers Ferry In Scott County


Significant NW to SE Rainfall Gradient 
Across Southwestern Virginia
( February 29-March 3, 2012 )

Woolwine: 0.34"

Galax WTP: 0.57"

Independence 1.3 S: 0.72"

Danville: 0.79"

Meadows of Dan 5 SW: 0.94"

Trout Dale 3 SSE: 1.19"

Wytheville 1 S: 1.25"

Tri-Cities ( TN ): 1.43"

Grayson Highlands State Park: 1.52"
( Elevation 4000 feet )

Grundy: 1.54"

Marion 4.4 WSW: 1.67"

Roanoke: 1.70"

Abingdon 3 S: 1.86"

Blacksburg: 1.95"

Richlands: 2.11"

Clintwood 1 W: 2.15"

Saltville 1 N: 2.20"

Burkes Garden: 2.38"

Lebanon: 2.42"

Nora 4 SSE: 2.67"
( Long Ridge of Tennessee Valley Divide )

Robinson Knob of High Knob Massif: 3.28"
( 5.5 air miles SE of Norton WP )

Norton Water Plant: 3.53"
( Northern base of High Knob Massif )

Jonesville 3.1 WSW: 3.56"
( Northern edge of The Cedars )


Some Final Thoughts

What I have covered above is strictly for historical documentation of atmospheric conditions which generated the greatest tornadoes ever observed in my life time from the Cumberland Mountains west across the Kentucky foothills.

While tornadoes are atmospheric marvels they are BEASTS.  Just as one would never lock old people, children, and babies inside a cage with hungry Lions, Tigers & Bears, they would not put homes & lives in the path of tornadoes who ravage anything in their way!

[ In a perfect world Tornadoes would only roam the high, open Plains where no one lives and we who are interested could study, photograph & film these incredible monsters at safe distances ].

Since the world is far from perfect there are points for learning and investigation presented above.

1 ).  That elevated convection will turn strong to severe can be anticipated under certain atmospheric conditions ( such as those documented in this case where many were surprised ).

2 ).  Extreme shear can compensate for a lack of surface based thermodynamics to drive long-track, violent tornadoes across Appalachian foothill terrain during astronomical winter.

3 ).  Highly visible, Great Plains-like tornadoes can occur in this region, even during winter, when vertical tilting of storms act to keep rotating updrafts separated from low energy downdrafts ( going against the rain-wrapped, short-lived twisters which are the climatological norm in rough Appalachian terrain ).

4 ).  The elevation of inflow bases and the best MUCAPE above relatively low foothill terrain appeared to minimize effects of crossing rough surface topography which rested well below these parameters for eastern Kentucky EF-2 to EF-3 tornadoes ( e.g., the powerful West Liberty and Salyersville tornadoes ).

5 ).  Lower inflow bases and better CAPE which formed a strong hook and TVS signature on a preferred, isolated supercell over far southeastern Kentucky during the same time period had much different results as it interacted with lofty mountain terrain upon crossing into Virginia [ i.e., no reported damage and a radical change in storm structure ( * ) ].

*Hail of 1" to 2.75" in diameter, and localized tree damage, was reported in Bell and Harlan counties with the supercell.

6 ).  An early evening transition back toward more typical Appalachian tornadoes occurred amid the rolling, open Powell River Valley at the southwestern end of the High Knob Landform and Cumberland Block during a atmospheric transitional period featuring significant gradients on various parameters.

7 ).  A supercell mode gave way to line echo wave pattern formation with a large bow developing within a climatologically favored position in which it has been documented many times in past cases ( i.e., with a relationship to orographics and air flow ).

In wake of the Big Stone Gap EF-1 tornado of March 4, 2008 I reminded everyone that current technology is simply not good enough to keep you safe in all conditions.

It is up to each of us to take responsibility for our own safety and the safety of family, friends and others whom we might be able to warn ( even before official warnings may or may not be given ).

The Great Plains-like tornadoes of March 2 were a rare departure from more typical, rain-wrapped, sudden and short-lived twisters most common in the Appalachians
( which are much harder to warn for in advance ).

The Storm Prediction Center, local NWS Forecast Officies out of Jackson, Ky., Charleston, Wv., and Morristown, Tn., as well as the TOR:CON of Dr. Greg Forbes, all did outstanding jobs during this historic severe weather outbreak ( as did local TV stations who remained on-air for hours during threatening conditions with many local thanks ).

With the above in mind, I recently found a blog by storm chaser, writer, and meteorologist Jon Davies that essentially echoed what I wrote in newspapers following the Big Stone Gap EF-1 of March 2008.

It is well worth a read!

Jon Davies - Meteorologist & Storm Chaser


NOTE: This website is set up to be best viewed using Internet Explorer 9 and Google Chrome web browsers ( text may be out of alignment using other browsers ).


Follow-Up Safety Note
The single common denominator that most tornado victims find simply shocking is how FAST it comes and goes.

The terror of a ROARING freight train 
that destroys in a flash of time!

It is very important for everyone to have a pre-designated safe place or room with head helmets and some type of body protection there now since when a tornado strikes there is NOT enough time to gather up needed items.

Tornado Safety - Storm Prediction Center

Reference this link to important information from experts at the Storm Prediction Center.

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