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Yangtze Cruise-Ship Disaster: Among the Worst Thunderstorm Tolls on Record?

By: Bob Henson 3:42 PM GMT on June 03, 2015

A picturesque vacation for hundreds of Chinese tourists turned into a nightmare on June 1, when high winds associated with an intense thunderstorm capsized the Oriental Star cruise ship in 50-foot-deep water on the Yangtze River in Hubei Province, southwest of Wuhan, at around 9:30 pm local time. As of Tuesday afternoon, only 14 people had been rescued from about 450 reportedly on board, most of them retirees on a multiday scenic cruise from Nanjing to Chongqing. The disaster appears set to become China’s deadliest ship-related accident in almost 70 years. It’s unclear whether the cruise ship was sunk by a tornado or by a microburst, but in either event, the death toll could end up among the largest on record associated with a single thunderstorm. A 2011 post by WU weather historian Christopher Burt showed less than 10 tornadoes worldwide that inflicted a greater toll than the potential 400-plus deaths abroad the Oriental Star. As we’ll see below, the event also brings to mind a similar U.S. tragedy almost 40 years ago.


Figure 1. Rescuers search for survivors from the capsized ship Dongfangzhixing (Eastern Star) in the Yangtze River on June 2, 2015, in Jingzhou, China. Image credit: ChinaFotoPress/Getty Images.


What caused the high winds?
Press coverage has led to some understandable confusion over exactly what caused the disaster. China’s Xinhua news agency reported that the China Meteorological Agency (CMA) detected winds “stronger than 12 scale,” apparently a reference to the Beaufort scale, where 12 corresponds to winds exceeding hurricane force (74 mph). The Guardian cites local media as reporting winds of 80 mph at the time of the accident. Several news reports called the event a cyclone, while others dubbed it a tornado. Given that tornadoes have cyclonically oriented winds, they are sometimes referred to as cyclones in news reports outside the United States. Moreover, according to the New York Times, “In Chinese, the term for tornado, longjuanfeng, is used more loosely than Americans use its English equivalent.”


Figure 2. An infrared satellite image taken at around midnight local time on Monday night, June 1, several hours after the Eastern Star ship was hit by high winds. Image credit: weather.com. An infrared loop from Japan’s new Himawari-8 satellite illustrates the same storm complex, with an blue “X” placed at the approximate location of the capsizing. Image credit: Japan Meteorological Agency, courtesy Dan Lindsey, Cooperative Institute for Research in the Atmosphere.


Satellite images from the region around the disaster show a large cluster of strong thunderstorms developing on Monday night local time (see Figure 2). Eastern Asia has some of the same thunderstorm-favorable features as the U.S. Great Plains, including mountains and dry air to the west and access to very warm, humid air toward the south and east. However, little has been published in the global science literature on the frequency of tornadoes across China. “Thunderstorms have certainly been plentiful across eastern and southern China over the past few days," said Jon Erdman in a weather.com article. "It's certainly possible one of those thunderstorms may have spawned a very unfortunately-timed tornado. . . .Also, strong straight-line, non-tornadic winds—common in clusters of thunderstorms like those seen in eastern China late Monday—may have played a role in the capsizing."

Harold Brooks (NOAA National Severe Storms Laboratory), an expert on international tornado climatology, inspected upper-air soundings collected across the central Yangtze region on Monday evening. Brooks told me the soundings were supportive of tornadic supercells, with ample instability (CAPE values of 1000 to 3000 J/kg) and adequate storm-relative helicity (a measure of potential updraft rotation). However, such conditions can also lead to high-precipitation storms that produce strong downburst winds but no tornado. “Given the environment, I wouldn't be surprised if it was a tornado or, at least, a strong rear-flank downdraft associated with a supercell,” said Brooks.

Monday’s storms developed along a seasonal feature called the Mei-yu front, a band of convergent winds associated with the northward push of the Asian monsoon in China and Japan. Each spring, the cold, parched winter climate of China transitions to a muggy summer regime that includes frequent rounds of torrential rain. Beijing’s average precipitation in July (7.3”) is far greater than its average in January (0.1”). The Asian monsoon is driven by southwesterly upper winds toward the northeast, so it reaches a higher latitude sooner than the Indian monsoon. This explains why heavy rains can strike central China (latitude 30°N) while parts of India as far south as 10°N have yet to see the monsoon. The Mei-yu front can stall out for weeks during May and June in the general vicinity of the Yangtze, leading to days of heavy thunderstorms along and near it. BBC reported that the Mei-yu rains this season have been the heaviest in 40 years across parts of south China.


Figure 3. A bridge damaged by flood water in Leishan county of southwest China’s Guizhou province on May 27, 2015. Parts of China have been hit by the heaviest spring rains in 40 years. Image credit: AFP/Getty Images.

The Whippoorwill disaster of 1978
Though far less deadly than its present-day counterpart in China, the capsizing of a pleasure boat called the Whippoorwill led to one of the ten worst tornado tolls in the history of Kansas. On June 17, 1978, the Whippoorwill carried 58 passengers on an evening cruise on the 4,000-acre Pomona Lake, about 30 miles south of Topeka. A small tornado, only about 150 yards wide but with multiple vortices, developed near the lake around 7:00 pm, according to a summary from the National Weather Service office in Topeka. Damage was minimal, but the suddenness of the tornado’s development and its unfortunate path led to the capsizing of the showboat. One victim recalled: “One minute we were serving salads, the next I was under water.” There were 16 fatalities. “Nationwide media coverage was focused on Kansas and this tornado for many days after the tragic event,” notes the NWS/Topeka. “People who boarded the Whippoorwill for an evening of fun and entertainment, likely never imagined what a historical catastrophe they were in for.” As part of the 50th anniversary of the creation of Pomona Lake, a memorial service was held last June 17 for the victims of the Whippoorwill disaster.

My thanks go to Harold Brooks (NOAA/NSSL), Roger Edwards (NOAA Storm Prediction Center), and WU weather historian Christopher Burt for background used in this article.

Bob Henson

Tornado

The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.

Reader Comments

Quoting 460. StormTrackerScott:

Strong El-Nino now beginning to take shape. AMJ ONI will likely come in @ 1.1C or 1.2C. MJJ though should come in @ or over 1.5C. 1997 didn't have a 1.5C or higher ONI until the JJA update



Quoting 500. Naga5000:



I lolled. Am I doing this right?


Nope. It would still be lol because the first "l" would then stand for Laughed instead of laugh. Take off the "led" Led is for lights and lights are no laughing matter
Quoting 487. vis0:

YOU'RE! sort-of** 110% wrong!**

To those observing weather for many yrs (decades) you're correct
To those observing weather for a few years (< decade) you're wrong as that HOP SKIP & A JUMP the MODEL does is a form of a game, excitement to the chase as you or Grothar stated,
.

To youngins just getting it correct on the first try would be like a pinball game where the ball goes from point A to B hits 1,000,000 pts with not 1 bumper bumping, bouncing(TILT) here & there x 100 with bells & whistles.

To seniors were looking for the compu'r to finally get 1 right on the first try, but compu'rs are not there yet and odds are won't be there for ??? yrs  Specially with country's attitude of lets see who wins figuring out weather modeling by only studying  a small area of the world (their country) instead of lets keep propriety on the publics use but share SCIENTIFICALLY all local weather knowledge so humanity can prevent tragedies as floods in Texas to over turned boats in China 'cause you'll make moner money locally if your company gets more forecasts correct which happens when a compu'r is feed more info and (here comes the all knowing knowlegde get a pencil & paper oops i mean stylus  & screen ) were all under 1 roof, a planet some call Earth..


**50% correct
**50% wrong
**5% to good taxes
**5% to bad taxes
Yes, you have a point. Having watched models from a time where they were just born until now, it is kind of the same old thing seeing them create storms which never really exist. If I was new at this, each model run showing a possible storm would be a lot more exciting. I wonder what the ratio is between model forecasted tropical lows and those that actually occur? Just from my memory, it seems like it has to be about 20 forecasted lows compared to an actual low.
Quoting 502. Hurricanes101:



Nope. It would still be lol because the first "l" would then stand for Laughed instead of laugh. Take off the "led" Led is for lights and lights are no laughing matter


Semantics. You say tomato, I say genetically modified tomato like organism. :)
can you trust the Nam 2 1/2 days out?.............................................. ............
Quoting 422. BaltimoreBrian:

What a wonderful picture Dakster!


Thanks BB!

Quoting 439. sar2401:

Nice picture. I've only seen a mother moose with her babies once. They had such tiny bodies and such long legs that I didn't know how they managed to stand up. This happened in Yellowstone. Something spooked mom and she took off across the road while the kids bounded off following her. I don't know how fast they were running on those spindly looking legs but they could have outrun me with no problem.


They were walking fairly quick in that picture at about my jogging speed, but they should could outrun me wihout a doubt. I wasn't getting any closer for a better shot - let's just put it that way.

Quoting 423. KEEPEROFTHEGATE:

it looks like great weather the wildlife adds to it


I thought the same thing when I saw the photo taken. It is a nice weather/wildlife photo. I plan on uploading it to my photos in the original resolution. Hopefully it will get an approvers choice award. I don't often get great photos, but I am proud of how this one came out.
Quoting 504. Naga5000:



Semantics. You say tomato, I say genetically modified tomato like organism. :)


you say genetically modified tomato, I say still tastes great in a sauce :)
Quoting 497. yoboi:


omg smh@cagw...
AWGTHTGTATA
Thank you Sar and 101!
JeffMasters has created a new entry.
Quoting 489. Neapolitan:

Well, it's an initialism, if that's what you mean. But it is an acceptable part of speech, according to the Oxford English Dictonary March 2011 update:




Actually is should be LA, as in "laugh aloud". I never used the expression "out loud". Just an old English thing with me.
Quoting 511. Grothar:



Actually is should be LA, as in "laugh aloud". I never used the expression "out loud". Just an old English thing with me.


I've always preferred SCTM (silently chuckling to myself).
Quoting 505. LargoFl:
can you trust the Nam 2 1/2 days out?.............................................. ............
If it agrees with the actual forecast out of Miami, you probably can.

Saturday - A chance of showers, then showers and thunderstorms likely after 8am. Mostly cloudy, with a high near 85. North wind 3 to 7 mph. Chance of precipitation is 60%.

Saturday Night - Showers and thunderstorms likely before 8pm, then a slight chance of showers. Mostly cloudy, with a low around 75. Southeast wind 6 to 9 mph. Chance of precipitation is 60%.
Quoting 511. Grothar:


Actually is should be LA, as in "laugh aloud". I never used the expression "out loud". Just an old English thing with me.


Actually Gro you would use Old English-
'laugh out loudeth'.


AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSONVILLE FL
345 PM EDT THU JUN 4 2015

.NEAR TERM /THROUGH TONIGHT/...
A WEAK FRONTAL BOUNDARY REMAINS STALLED ALONG THE GULF COAST TO
THE I-10 CORRIDOR INTO JACKSONVILLE AND THEN UP THE EASTERN
SEABOARD TO THE CAROLINAS. A FEW SHOWERS HAVE RECENTLY FIRED UP
ALONG THIS BOUNDARY NEAR AND JUST WEST OF THE I-95 CORRIDOR
DUE TO THE INCREASED LOW LEVEL CONVERGENCE ASSOCIATED WITH THE
INLAND PUSH OF THE ATLANTIC COAST SEABREEZE. AS OF 3 PM...NO CLOUD
TO GROUND LIGHTNING STRIKES HAVE BEEN OBSERVED. DRY AIR ALOFT...AS
SEEN ON WATER VAPOR IMAGERY WRAPPING AROUND THE UPPER LOW OVER THE
CAROLINAS...HAS THUS FAR KEPT CONVECTION TAME AND SHALLOW.

CONVECTIVE ACTIVITY WILL CONTINUE TO SHIFT INLAND WITH THE
SEABREEZE. MOST IF NOT ALL OF THIS CONVECTION WILL REMAIN WIDELY
SCATTERED AND FAIRLY LOW TOPPED WITH MINIMAL LIGHTNING STRIKES.
THE EXCEPTION COULD POSSIBLY BE LATE THIS AFTERNOON INTO THIS
EVENING AS THE ATLANTIC COAST SEABREEZE MERGES WITH THE GULF COAST
SEABREEZE ALONG THE I-75 CORRIDOR. THIS COULD PROVIDE ENOUGH LIFT
TO GET PAST THE MID LEVEL CAP WHICH IN RETURN WOULD RESULT IN
POTENTIALLY AN ISOLATED STRONG STORM BUT CONFIDENCE IN THIS
SCENARIO REMAINS LOW GIVEN THE CURRENT TRENDS AND LATEST WATER
VAPOR IMAGERY.

CONVECTION WILL WIND DOWN QUICKLY THIS EVENING WITH ONLY A SLIGHT
CHANCE OF A LIGHT SHOWER OR TWO ACROSS OUR NORTHERN ZONES AND
ALONG THE ATLANTIC COAST AS THE MID LEVEL TROUGH AXIS PIVOTS
ACROSS THE REGION.

.SHORT TERM....FRIDAY THROUGH SUNDAY...LOW TO MID LEVEL HIGH PRES
RIDGE WILL REMAIN TO OUR W WHILE MID TO UPPER TROUGH REMAINS ALONG
THE E COAST OR OFFSHORE. RESULTANT FLOW LOW TO MID LEVEL FROM THE N
TO NE EXPECTED WHICH WILL FAVOR A QUICKER INLAND PROGRESSION OF THE
E COAST SEA BREEZE. SUFFICIENT MOISTURE IS AVAILABLE FOR ISOLD TO SCT
CONVECTION EACH DAY...WITH SUNDAY POSSIBLY SEEING AN UPTICK IN THE
ACTIVITY WITH GFS AND TO SOME EXTENT THE ECMWF SHOWING MID LEVEL
LOW OR ENHANCED SHORTWAVE ENERGY PUSH N TO S FROM GA TO FL AND
MOISTURE LEVELS INCREASING AND COOLER MID LEVEL TEMPS OF -11C. FOR
NOW HAVE MAINTAINED RAIN CHANCES IN THE 20 TO 40 PERCENT RANGE FOR
FRI AND SAT...AROUND 40 TO 50 PERCENT FOR SUNDAY. DRY AIR IN THE MID
LEVELS MAY RESULT IN AN ISOLD RISK FOR STRONG/LOCALLY SEVERE
DOWNBURST WIND POTENTIAL DURING THIS PERIOD. HIGH TEMPERATURES WILL
RANGE FROM THE MID 80S COAST TO THE LOWER 90S WELL INLAND.

.LONG TERM...MONDAY THROUGH THURSDAY...MID LEVEL RIDGE WILL BE OVER
THE REGION MONDAY THEN WEAKENS AND SHIFTS WWD AS BROAD TROUGH/NEAR
ZONAL FLOW DEVELOPS TUE THROUGH THU. POPS LOOK RELATIVELY LOW
PERHAPS BELOW CLIMO WITH A LOW END CHANCE EACH AFTERNOON/EVENING.
MOISTURE LEVELS MAY INCREASE WED THROUGH THU TO PUSH POPS HIGHER BUT
NOT TOO CONFIDENT IN THIS YET DUE TO MORE WIDESPREAD MODEL SOLUTIONS
FROM GFS AND ECMWF. TEMPERATURES WILL RISE TO SLIGHTLY ABOVE NORMAL
LEVELS.

&&