4/27-4/28 Tornado Outbreak Damage Assessment Thread

[Memphis Weather]

HUN has upgraded the Dekalb County Tornado to EF5. However...their assignment of 200mph is still EF4 range (Operationally...5 begins at 201mph). They should correct that information to 205mph if they intend EF5 to make it absolutely clear. This would make the 6th EF5 of the year now...tying the record of 1974.

...ADDITIONAL INFORMATION LEADS TO AN UPGRADE OF DEKALB COUNTY

TORNADO FROM APRIL 27TH TO AN EF-5...

AN ADDITIONAL GROUND SURVEY BASED ON NEW INFORMATION WAS CONDUCTED

ON JUNE 15TH ALONG A NARROW CORRIDOR OF DEKALB COUNTY EAST AND

NORTHEAST OF DOWNTOWN RAINSVILLE. THIS STORM SURVEY WAS UTILIZED

ALONG WITH AERIAL IMAGERY FROM A NOAA OVERFLIGHT ON MAY 4TH,

INTERVIEWS WITH RESIDENCES IN THE AREA, AND ADDITIONAL PRE-EVENT

IMAGERY TO UPDATE THE PREVIOUS RATING FOR THE LONG TRACK TORNADO THAT

IMPACTED DEKALB COUNTY ON APRIL 27TH.

FINDINGS INCLUDING THE UPDATED SURVEY INFORMATION ARE AS FOLLOWS:

* EVENT TYPE: TORNADO

* EVENT DATE: 04/27/11

* EVENT TIME: 6:19 PM TO 6:56 PM

* ESTIMATED PEAK WIND: 200.0 MPH

* PRELIMINARY RATING: EF-5

* PATH LENGTH: 33.8 MILES

* MAXIMUM PATH WIDTH: 0.75 MILES

* BEGINNING POINT: 34.90708 / -85.978378

* MID POINT:34.507738/ -85.790106

* ENDING POINT: 34.733306 / -85.557820

* UPDATED SURVEY INFORMATION GATHERED ON JUNE 15TH:

FOR THE PURPOSES OF FURTHER STUDY, THE NATIONAL WEATHER SERVICE

FOCUSED PRIMARILY ON A NARROW CORRIDOR OF INTENSE DAMAGE EXTENDING

FROM SKAGGS ROAD TO LINGERFELDT ROAD (ALSO KNOWN AS COUNTY ROAD 180)

EXTENDING TOWARD COUNTY ROAD 514. ALONG SKAGGS ROAD, A STONE HOUSE

WAS COMPLETELY OBLITERATED WITH MUCH OF THE INTERIOR DEBRIS STREWN

WELL AWAY FROM THE STRUCTURE. A SUPPORTING LARGE CEMENT AND STONE

PILLAR WAS RIPPED COMPLETELY OUT OF THE GROUND. ANOTHER HOME ALONG

SKAGGS ROAD WAS ALSO LEVELED COMPLETELY TO THE GROUND. THE NOAA

OVERFLIGHT SHOWED SIGNIFICANT GROUND SCARRING IN THIS AREA AND A WALK

THROUGH THE NEARBY FIELDS SHOWED LARGE POT MARKS AND OTHER SECTIONS

OF DISTURBED GROUND.

SLIGHTLY NORTHEAST ALONG LINGERFELDT ROAD, NUMEROUS HOMES WERE LEVELED

COMPLETELY TO THEIR FOUNDATION WITH VEHICLES AND DEBRIS STREWN FOR

HUNDREDS OF FEET. OVERHEAD PHOTOS AND FOLLOW-UP VISUAL CONFIRMATION

REVEALED A MANGLED VEHICLE TOSSED WELL INTO A RAVINE AND RESTING UP

IN THE REMAINDER OF TREES. AT 1608 LINGERFELDT ROAD/CR 180 A LARGE

TWO STORY BRICK HOME WAS COMPLETELY OBLITERATED WITH SEVERAL OF THE

SUPPORTING ANCHORS RIPPED OUT OF THE GROUND. A CONCRETE PORCH WAS

RIPPED OFF WITH PIECES STREWN UP TO 150 YARDS. A SECTION OF THE

ASPHALT DRIVEWAY WAS PULLED UP. IN ADDITION, AN ANCHORED LIBERTY SAFE

WEIGHING 800 POUNDS WAS PULLED OFF ITS ANCHORAGE AND THROWN INTO A

WOODED AREA 600 FEET AWAY. WHEN FOUND, THE SAFE'S DOOR HAD BEEN RIPPED

OPEN AND COMPLETELY OFF. A LARGE PICK-UP TRUCK AT THIS RESIDENCE WAS

FOUND MANGLED IN PIECES OVER 250 YARDS AWAY IN THE SAME WOODED AREA.

THE RESIDENTS OF THE HOME SURVIVED IN A NEARBY STORM PIT. OF NOTE THE

STORM PIT WAS PARTIALLY EXPOSED BY THE TORNADO WITH DIRT BEING SUCKED

UP AND PULLED AWAY AROUND THE OPENING. NEXT DOOR A MOBILE HOME WAS

COMPLETELY DISINTEGRATED. THE RESIDENTS OF THE MOBILE THERE ALSO

SURVIVED IN A STORM PIT.

THIS SECTION OF DAMAGE FROM SKAGGS ROAD TO LINGERFELT ROAD NEAR THE

INTERSECTION WITH CROW LANE WAS DEEMED TO BE EF-5 IN INTENSITY.

IT SHOULD ALSO BE NOTED THAT SEVERE DAMAGE, NEAR EF-5 IN INTENSITY WAS

NOTED IN A CORRIDOR FROM CR 515 THROUGH A NEIGHBORHOOD ALONG COUNTY

ROAD 441. IN THE EAST AND SOUTH ENDS OF THE NEIGHBORHOOD, MANY ONE

AND TWO STORY HOMES WERE LEVELED TO THEIR FOUNDATION WITH DEBRIS

SCATTERED SOME DISTANCE. SEVERAL CARS WERE THROWN A LARGE DISTANCE IN

THIS AREA. THERE WAS EVIDENCE OF GROUND SCARRING AS WELL AS SOME

SIDEWALK PAVEMENT PULLED UP IN THIS LOCATION. HOWEVER, SOME OF THE

HOMES IN THIS AREA APPEARED TO BE PUSHED OFF THEIR FOUNDATION

INITIALLY WITH LIMITED ANCHORAGE. THUS, THE DAMAGE WAS DEEMED HIGH

END EF-4 IN THIS AREA.

THESE FINDINGS ARE STILL PRELIMINARY AND ARE SUBJECT TO ADJUSTMENT

BEFORE A FINAL REPORT IS COMPLETED. ALSO NOTE THAT THE FINAL REPORT

MAY INCLUDE A SLIGHT ADJUSTMENT TO THE BEGINNING POINT OF THE TRACK.

PICTURES AND SUMMARY MATERIALS WILL BE MADE AVAILABLE ON OUR WEB PAGE

AT WEATHER.GOV/HUNTSVILLE /ALL LOWER CASE/.

[ArtRosen]

This is the second worst tornado season on record as far as the number of recorded EF5s are concerned and concerning how difficult it is to obtain an EF-5 rating today compared with 35 years ago, I'd probably say this is the most severe season ever recorded due to more accurate readings, and better built homes and buildings.

[Memphis Weather]

Good job HUN! Already corrected

* ESTIMATED PEAK WIND: >200.0 MPH

* PRELIMINARY RATING: EF-5

[thewxmann]

:DDDDDDDDDDDDDDD

I knew that if one of the tornadoes was to be upgraded (besides Tuscaloosa), it'd be the DeKalb County one.

EDIT: on a more solemn note, this part was really amazing:

IN ADDITION, AN ANCHORED LIBERTY SAFE

WEIGHING 800 POUNDS WAS PULLED OFF ITS ANCHORAGE AND THROWN INTO A

WOODED AREA 600 FEET AWAY. WHEN FOUND, THE SAFE'S DOOR HAD BEEN RIPPED

OPEN AND COMPLETELY OFF. A LARGE PICK-UP TRUCK AT THIS RESIDENCE WAS

FOUND MANGLED IN PIECES OVER 250 YARDS AWAY IN THE SAME WOODED AREA.

[blackjack123]

:DDDDDDDDDDDDDDD

I knew that if one of the tornadoes was to be upgraded (besides Tuscaloosa), it'd be the DeKalb County one.

EDIT: on a more solemn note, this part was really amazing:

IN ADDITION, AN ANCHORED LIBERTY SAFE

WEIGHING 800 POUNDS WAS PULLED OFF ITS ANCHORAGE AND THROWN INTO A

WOODED AREA 600 FEET AWAY. WHEN FOUND, THE SAFE'S DOOR HAD BEEN RIPPED

OPEN AND COMPLETELY OFF. A LARGE PICK-UP TRUCK AT THIS RESIDENCE WAS

FOUND MANGLED IN PIECES OVER 250 YARDS AWAY IN THE SAME WOODED AREA.

Just reading the description of what this tornado blows my mind completely proportion. Concrete steps ripped off the foundation or concrete slab pulled upward. You know what they mean when they say incredible phenomena will occur.

[ineedsnow]

some of the damage i saw from springfield tornado should have been rated as EF4 but thats my opinion!! Amazing that i was so close to it! Scariest thing i ever been threw!

[thewxmann]

Bump, NWS BMX updated the survey info for the TCL-BHM tornado for Pleasant Grove and points east:

http://www.srh.noaa.gov/bmx/?n=event_04272011tuscbirm

The tornado continued northeastward out of the Concord area and into the Pleasant Grove community. EF-4 damage was prevalent here, with slabs wiped clean, though the debris from each home had not been removed by the winds. The majority of it remained within a couple of yards of the home. It was here in Pleasant Grove where evidence of vehicles being moved by the winds become obvious, though most were only tossed 10 to 15 yards if they were picked up at all. Additionally, wind rowing of debris was evident throughout the Pleasant Grove community which is characteristic of a storm of thismagnitude.

The tornado quickly moved out of the Pleasant Grove area and into the McDonald Chapel community. It was here in McDonald Chapel where evidence of a slight weakening of the tornado became clear. No vehicles were tossed, only pushed slightly from their original position. Many homes in this area were constructed by the method of pier and beam foundation, which led to some of the major destruction, as this construction will not withstand winds of this magnitude. A four-sided brick home in the same area only lost a roof and no exterior walls, which is indicative of EF-2 damage. At least one death occurred here.

After moving through the McDonald Chapel area the tornado moved into the area of Smithfield Estates, with significant home damage along Cherry Avenue between Daniel Payne Drive and Veterans Memorial Drive. Numerous homes sustained damage in this area, and a 2-story apartment complex had a large portion of its roof lifted and removed. The Bethel Baptist Church also sustained significant damage to its roof, though the main structure of the Building was still intact. The damage sustained in this area is consistent with EF-2 wind damage. Although not a main damage indicator, there was also evidence of vehicles being moved, but only a couple of feet.

By the time the tornado reached Interstate 65, it was evident that the storm was losing its energy. The damage in the Fultondale area included folded highway light poles along the Interstate, and roof damage to the Days Inn on U.S. Highway 31. To the east of US-31, the damage quickly diminished from EF-2 intensity to EF-1 and EF-0. The tornado lifted just to the west of Alabama Highway 79, about 2 miles north of the city of Tarrant, though the storm was not done. The storm did regenerate itself and eventually put down the EF-4 tornado in the Ohatchee area.

[thewxmann]

Bump.

BMX has finalized their surveys from April 27th (and also April 15th).

Their AL tornado database includes now all tornadoes through May 2011: http://www.srh.noaa.gov/bmx/?n=tornadodb_2011. Updates in the database include an upgrade of Hackleburg damage from 205 to 210 mph, and exclusion of 7 indirect fatalities from the Tuscaloosa-Birmingham tornado death toll.

Finally, the relevant BMX PNS that summarizes it all:

000

NOUS44 KBMX 271307 CCA

PNSBMX

ALZ011>015-017>050-280100-

PUBLIC INFORMATION STATEMENT

NATIONAL WEATHER SERVICE BIRMINGHAM AL

200 PM CDT FRI AUG 26 2011

...DATA FINALIZED FOR THE APRIL 2011 HISTORIC TORNADO OUTBREAKS...

THE MONTH OF APRIL 2011 BROUGHT WITH IT AN UNPRECEDENTED AMOUNT OF

SEVERE WEATHER. BESIDES MULTIPLE DAYS WITH DAMAGING STRAIGHT LINE

WIND EVENTS, THERE WERE TWO DAYS WHICH USHERED IN A RECORD NUMBER OF

TORNADOES WHICH INCLUDED SEVERAL VIOLENT TORNADOES.

AS PART OF A SYSTEM WHICH WREAKED HAVOC ON THE EASTERN HALF OF THE

UNITED STATES FROM APRIL 14TH TO APRIL 16TH, WIDESPREAD SUPERCELLS

BROUGHT A RECORD NUMBER OF TORNADOES TO ALABAMA ON APRIL 15TH. ON

THIS DAY ALONE, ALABAMA EXPERIENCED 45 TORNADOES, ALL OF WHICH WERE

EF-3 OR WEAKER.

A LITTLE MORE THAN A WEEK LATER, FROM APRIL 25TH TO APRIL 28TH, MUCH

OF THE EASTERN HALF OF THE UNITED STATES EXPERIENCED ONE OF THE MOST

EXTENSIVE TORNADO OUTBREAKS THIS COUNTRY HAS EVER SEEN. CENTRAL

ALABAMA TOOK THE BRUNT OF ITS DAMAGE ON APRIL 27TH. FIRST, A QUASI-

LINEAR CONVECTIVE SYSTEM MOVED THROUGH DURING THE EARLY MORNING

HOURS, FOLLOWED BY THE OUTBREAK OF VIOLENT TORNADIC SUPERCELLS IN

THE AFTERNOON. THE MORNING ACTIVITY PRODUCED WIDESPREAD WIND DAMAGE

AND SEVERAL TORNADOES. THE AFTERNOON ACTIVITY PRODUCED THE MAJORITY

OF THE MOST INTENSE DAMAGE. ON THIS DAY, ALABAMA EXPERIENCED

62 TORNADOES.

A THOROUGH STUDY OF EACH TORNADO PATH HAS BEEN CONDUCTED. SEVERAL

NATIONAL WEATHER SERVICE OFFICES, STATE AND COUNTY EMERGENCY

MANAGEMENT OFFICIALS, AND SEVERAL NATIONAL INVESTIGATORS COORDINATED

AND ANALYZED THESE DATA SETS. THIS STATEMENT WILL SERVE AS THE FINAL

INFORMATIONAL STATEMENT ABOUT THESE TWO HISTORIC EVENTS. HERE ARE

SOME STATISTICS FROM THOSE TWO DAYS:

...CENTRAL ALABAMA STATISTICS FROM THOSE TWO FATEFUL DAYS...

TORNADOES ARE OFFICIALLY RANKED BY THE MOST INTENSE STRENGTH ALONG

THE ENTIRE PATH. FOR EXAMPLE, THE SMITHVILLE, MS, TORNADO ON

APRIL 27TH WAS RANKED AS AN EF-5. EVEN THOUGH THE TORNADO ONLY

REACHED EF-3 STRENGTH IN CENTRAL ALABAMA, FOR THE RECORD, THE WHOLE

TORNADO IS RANKED EF-5. IF YOU ARE INTERESTED IN THE TORNADO

STRENGTH IN ALABAMA ONLY, IT WOULD BE AN EF-3. THERE WERE SEVERAL

SUCH TORNADO INCIDENTS DURING THESE EVENTS.

ON APRIL 15TH AND APRIL 27TH, THERE WERE 29 TORNADOES EACH DAY IN

CENTRAL ALABAMA.

THE ACTUAL TORNADO STRENGTH BREAKDOWN IN CENTRAL ALABAMA FOR

APRIL 15TH LOOKS LIKE THIS:

EF-5: 0

EF-4: 0

EF-3: 4

EF-2: 10

EF-1: 10

EF-0: 5

THE ACTUAL TORNADO STRENGTH BREAKDOWN IN CENTRAL ALABAMA FOR

APRIL 27TH LOOKS LIKE THIS:

EF-5: 1

EF-4: 4

EF-3: 8

EF-2: 5

EF-1: 10

EF-0: 1

THERE WERE A TOTAL OF 4 DEATHS DIRECTLY RELATED TO THE TORNADOES IN

CENTRAL ALABAMA ON APRIL 15TH.

THERE WERE A TOTAL OF 139 DEATHS DIRECTLY RELATED TO THE TORNADOES

IN CENTRAL ALABAMA ON APRIL 27TH.

OF THOSE 139 DEATHS ON APRIL 27TH, 86 PEOPLE WERE KILLED IN

PERMANENT STRUCTURES, SUCH AS A HOME, FACTORY OR CHURCH. 46 WERE

KILLED WHILE IN MANUFACTURED HOMES. 2 FATALITIES OCCURRED WHILE

PEOPLE WERE STILL IN THEIR VEHICLES AND 2 OTHERS WHILE OUTDOORS.

THESE NUMBERS ARE COURTESY OF FEMA, LOCAL EMA AND THE RED CROSS.

...STATEWIDE STATISTICS FOR THOSE TWO FATEFUL DAYS...

ON APRIL 15TH, THE STATE OF ALABAMA SET A RECORD FOR THE NUMBER OF

TORNADOES ON ONE CALENDAR DAY WITH 45. THE PREVIOUS RECORD WAS SET

ON THE VETERANS DAY OUTBREAK OF NOVEMBER 24, 2001 WHEN 36 TWISTERS

TOUCHED DOWN.

TWELVE DAYS LATER, ON APRIL 27TH, THE RECORD SET ON APRIL 15TH WAS

BROKEN WHEN 62 TORNADOES TORE ACROSS THE STATE.

THERE WERE 7 DEATHS IN THE STATE OF ALABAMA ON APRIL 15TH.

SINCE 1874, ALABAMA HAD ONLY EXPERIENCED 6 EF-5 TORNADOES. ON APRIL

27TH ALONE, 3 OCCURRED.

SINCE 1874, ALABAMA HAD EXPERIENCED 64 EF-4 TORNADOES. ON APRIL 27TH

ALONE, 8 OCCURRED.

THE 129-MILE LONG CORDOVA EF-4 TORNADO RANKS SECOND LONGEST IN

ALABAMA RECORDED HISTORY TO THE GUIN EF-5 IN APRIL 1974 (135 MILES).

APRIL 27TH SAW 5 OF THE 10 LONGEST TORNADO TRACKS IN RECORDED

HISTORY.

THERE WERE 247 DEATHS IN THE STATE OF ALABAMA ON APRIL 27TH. THIS

RANKS AS THE SECOND DEADLIEST DAY IN ALABAMA BEHIND THE MARCH 1932

OUTBREAK WHEN 270 DIED.

...ADDITIONAL INFORMATION...

FOR MORE SPECIFIC AND DETAILED INFORMATION ABOUT EACH TORNADO PATH,

PLEASE VISIT THE WEB SITES OF EACH NATIONAL WEATHER SERVICE OFFICE

THAT WAS AFFECTED:

NWS BIRMINGHAM

WWW.SRH.NOAA.GOV/BMX/?N=EVENT_04272011 (ALL LOWER CASE)

NWS JACKSON

WWW.SRH.NOAA.GOV/JAN/?N=2011_04_25_27_SVR (ALL LOWER CASE)

NWS HUNTSVILLE

WWW.SRH.NOAA.GOV/HUN/?N=HUNSUR_2011-04-27_MAIN (ALL LOWER CASE)

NWS MOBILE

WWW.SRH.NOAA.GOV/MOB/?N=20110427_TOR (ALL LOWER CASE)

NWS PEACHTREE CITY

WWW.SRH.NOAA.GOV/FFC/?N=20110427_SVRSTORMS (ALL LOWER CASE)

FOR ADDITIONAL INQUIRIES, PLEASE CONTACT;

WARNING COORDINATION METEOROLOGIST JOHN DE BLOCK AT 205-664-3010,

EXT. 223, OR METEOROLOGIST IN CHARGE JIM STEFKOVICH AT 205-664-3010,

EXT. 222.

A SPECIAL THANKS TO THE MANY COUNTY EMERGENCY MANAGEMENT OFFICIALS,

THE ALABAMA STATE EMA, THE FEDERAL EMERGENCY MANAGEMENT AGENCY, THE

ALABAMA NATIONAL GUARD, LOCAL POLICE OFFICIALS, THE ALABAMA STATE

TROOPERS AND LOCAL FIRE OFFICIALS FOR THEIR ASSISTANCE WITH THE

NUMEROUS STORM SURVEYS.

A MAJOR CONTRIBUTION TO THE SUCCESS OF OUR SEVERE WEATHER WARNING

PROGRAM IS THE RECEIPT OF STORM REPORTS FROM ALL OUR CUSTOMERS AND

PARTNERS ACROSS CENTRAL ALABAMA. IF YOU WITNESSED OR ARE AWARE OF

ANY STORM DAMAGE DUE TO HIGH WINDS OR TORNADOES, PLEASE CONTACT YOUR

LOCAL EMERGENCY MANAGEMENT OFFICE OR CALL OUR STORM REPORTING

HOTLINE AT 1-800-856-0758.

[thewxmann]

Looks like NWS has finalized almost everything from 4/27. The storm data from all NWSFO's has been uploaded to the storm events database:

http://www4.ncdc.noa...?wwevent~storms

The final toll from 4/27-28: 316 dead, 2768 injured, $4.6 billion in property damages ($2.2 billion from Tuscaloosa-Birmingham. ~$1.2 billion from Hackleburg-Phil Campbell-Tanner-Harvest).

[dan11295]

Looks like NWS has finalized almost everything from 4/27. The storm data from all NWSFO's has been uploaded to the storm events database:

http://www4.ncdc.noa...?wwevent~storms

The final toll from 4/27-28: 316 dead, 2768 injured, $4.6 billion in property damages ($2.2 billion from Tuscaloosa-Birmingham. ~$1.2 billion from Hackleburg-Phil Campbell-Tanner-Harvest).

Amazing stat that this year saw the two costiest single tornadoes and 3 of the 5 costliest when adjusted for inflation based on this page. Curious as to why the Hackleburg storm was so damaging. All the other tornadoes on that list hit a sizable metro area. Just the length of the track?

[Hoosier]

Amazing stat that this year saw the two costiest single tornadoes and 3 of the 5 costliest when adjusted for inflation based on this page. Curious as to why the Hackleburg storm was so damaging. All the other tornadoes on that list hit a sizable metro area. Just the length of the track?

While we're on the subject of damages, here is a paper that examined tornadoes back to 1890:

http://journals.ametsoc.org/doi/pdf/10.1175/1520-0434%282001%29016%3C0168%3ANDFMTI%3E2.0.CO%3B2

[thewxmann]

Amazing stat that this year saw the two costiest single tornadoes and 3 of the 5 costliest when adjusted for inflation based on this page. Curious as to why the Hackleburg storm was so damaging. All the other tornadoes on that list hit a sizable metro area. Just the length of the track?

I'm kinda surprised too. They list $1 billion of that damage from the Limestone Co segment alone, which is kinda weird, since all other segments (including Hackleburg, Phil Campbell, Harvest - the last of which they list with $0.0 for property damages) add up to ~250 million.