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Australia cleans up from Larry

By: Dr. Jeff Masters, 6:00 PM GMT on March 21, 2006

Emergency work continues in the Queensland territory of Australia, where Tropical Cyclone Larry roared ashore Sunday near the town of Innisfail as a major Category 3 hurricane with sustained winds of 118 mph and gusts to 180 mph. Larry caused tremendous damage to crops and buildings, causing at least $400 million in damage and leaving 7000 people homeless. Fortunately, no deaths or major injuries occurred. Larry may be the strongest tropical cyclone to affect the east coast of Australia, and the most damaging cyclone to affect Australia since Tropical Cyclone Tracy devastated Darwin on Christmas Eve in 1974, killing 71 and leaving 20,000 homeless.

Media reports continue to confuse people by referring to Larry as a Category 5 storm, and not clarifying that this was on the Australian severity category system, a one to five ranking system based on the maximum wind gusts of a storm. A storm that has wind gusts in excess of 174 mph (280 km/h) is classifed as a Category 5. In the U.S. Saffir-Simpson scale that we are familiar with, the strength of a storm is based on the sustained winds, not the gusts. According the Australian Bureau of Meteorology, Tropical Cyclone Larry at landfall had 118 mph sustained winds. Adam Moyer, a grad student at Penn State, just pointed out to me that the Australians use a 10-minute average to report their sustained winds, while the U.S. NHC uses a 1-minute average. Thus, the sustained 1-minute average wind speeds of Larry were probably closer to 130 mph--the high end of the Category 3 range on the Saffir-Simpson scale. Category 3 sustained wind speeds range from 111 to 130 mph. However, the maximum 1-minute sustained winds as estimated by the Joint Typhoon Warning Center were 115 mph, gusting to 145 mph. The Australians and the Joint Typhoon Warning Center both maintain their own "official" data bases of tropical cyclones, so we can see that for Larry these will disagree. This disagreement highlights some of the problems researchers who are attempting to make a connection between global warming and hurricane intensity have--which "official" data base do you use for the Southern Hemisphere? You get a different answer depending upon which database you use.

Figure 1. Tropical Cyclone Wati off the coast of Australia as a minimal hurricane with 75 mph winds.

What's up next for Australia?
Currently, Tropical Cyclone Wati (a Category 1 hurricane on the Saffir-Simpson scale), is just off the east coast of Australia in a location similar to where Larry came ashore. Wati is expected to recurve to the south and weaken over the next three days, but may come close enough to the coast for warnings and watches to be issued. On Australia's west coast, there is Tropical Storm Floyd to worry about. Floyd is expected to become a Category 2 hurricane by Thursday.

The Southern Hemisphere tropical cyclone season runs November through April, and there should be only one or two more tropical cyclones this Spring in the Southwest Pacific (off of the east coast of Australia) and the southern Indian Ocean (off of the west coast of Australia). So far, the hurricane season in the Southwest Pacific has been about average, and the hurricane season in the South Indian ocean has been below average.

For the Southwest Pacific so far this hurricane season, here are the storm numbers, followed by averages in parentheses:

Tropical storms: 7 (9)
Hurricanes: 4 (5)
Major hurricanes, Cat 3-4-5: 1 (2)

And for the South Indian ocean:

Tropical storms: 12 (17)
Hurricanes: 4 (9)
Major hurricanes, Cat 3-4-5: 3 (5)

Jeff Masters

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

Thank you for the update Dr. Masters. Does the southern hemisphere have El Nino/La Nino?
I suspect that the 2006 North Atlantic season will continue the active phase that started in the mid 90's.

Living in Florida I am particularly concerned since the new warm phase in North Atlantic sea temperatures will likely result in more frequent encounters with major (cat 3-5) storms. See my post on March 2nd
To Collinsfarm
Currently there is a La Nina meaning cooler than normal sea surface temperatures in the equatorial Pacific

thanks fredwx. i appreciate the answer and link.
Don't forget about Floyd, off the western coast of Australia; the JTWC predicts it to reach 85 knots in two days (presently at 40 kts; the current path takes it away from land but it could recurve):

Wasn't the name Floyd retired in 1999?
I did forget about Floyd! I've added a mention, and talked more about disagreement between the Australian way of estimating hurricane winds and the NHC and JTWC.

Floyd was retired in the Atlantic, but it can be used in other ocean basins. There are several names that are used in multiple ocean basins.

Jeff Masters
When you say that Floyd is expected to become a cat-2, is that on the SS Scale, or the Australian scale?
The JTWC predicts Floyd to reach 85 knots in 2 days, which is a Category 2 on the Safir-Simpson Scale. Australia already says that Floyd is at Category 2 strength.
You can go here to find advisories from the official TCWCs.

This is the JTWC's site.

Links to both of these sites can also be found on the NHC's homepage, where is says "Tropical Cyclone Centers Worldwide".
Alright, thanks.
Thanks for the total storm numbers so far from the other basins. With the trend since '95 to be below average season totals for the other basins, with the North Atlantic above, I had wondered how it all was adding up so far.

For 0500 EST on Wednesday the 22nd of March 2006

At 5am EST Tuesday, Severe Tropical Cyclone Wati, category 3 with central
pressure 970 hPa, was centre over the central Coral Sea.

Wati is positioned at 5am near 17.4S 153.7E, which is about 630 km northeast of
Mackay. Tropical Cyclone Wati is moving towards the west-northwest at 10 km per
hour and should gradually intensify over the next 24 hours.

Wati is expected to remain slow moving in offshore waters for the rest of the
week. The combination of this system and a 1028 hPa high in the Tasman Sea is
expected to produce strong to gale force winds off the coast between Bowen and
Fraser Island. Large seas will develop along open waters of the southern and
central coasts.

The next bulletin will be issued at 11am Wednesday.
The human tornado riding distance (& surviving) was broken March 12, in Fordland, Mo.

The National Weather Service arrived at the final distance - 1,307 feet - using global positioning satellite technology. Tom Grazulis, a Vermont-based author and tornado researcher, said that is the farthest anyone has been carried by a twister - and survived.

The longest previously documented incident, he said, happened in Bowdle, S.D., on July 1, 1955, when a tornado carried a 9-year-old girl and her pony 1,000 feet before setting them down virtually unhurt.

The story
Thats a sweet record to hold.

Giants in 06
Anyone seen Chaser's blog? Ugh.
ForecasterColby mail for you

nice site to see the two storms
And yet, when non ignorant people like myself do disprove it, you ignore it.

If anyone wants to enter, I'm doing a smiley contest at my site.
cyclonebuster wrote::

"Don't you love it when ignorant people like this can't disprove my theory?"

don't you love it when ignorant people come up with an idea such as your tunnells can't prove their idea even works? no paperwork. no diagrams. nothing.

you're a hypocrite anyway. you lose.
Oh boy. I knew it couldnt last forever, and someday you'd be back cyclonebuster.

The fact that you still demand that we disprove when in reality, THE BURDEN OF PROOF IS ON YOU, shows that you hardly understand science in general, let alone the more detailed aspects of physics or meteorology. YOU have to show US the math that it works, not the other way around. Why can't you understand that?
That's irrelevant. You are exhibiting the illogical fallacy known as false analogy.

Your objective here to is to prove your tunnels create upwelling, not that upwelling weakens hurricanes. Proving that upwelling happens doesnt prove your tunnels create upwelling similar to these humps and mountains you're so fond of. You must use the equations and do the math. Only then will you have proof that your tunnels work.
Here are some reasons I can think of to NOT build the tunnels.

Cost: It would likely cost billions, if not trillions of dollars.

Unknown Effect on Enviroment: No one knows exactly what the effects on global temperatures. While it is almost certain that it would cool global temperatures, it is not clear if some areas might be forced into an ice age.

Politics: It would require all major countries in the world to agree that the tunnels were necessary, and to help with the cost.

Lack of Scientific Evidence: No one (including you) has provided any evidence thus far to support that these tunnels could effectively regulate the temperature of the ocean surface. Even if you could keep the sea surface at a constant temperature, it is unknown what effect it would have on storms. For all we know, lower sea temperatures could increase the frequency of Florida experiencing freezing conditions, it could increase the frequency of blizzards in places such as Philadelphia, New York City, Boston, and European cities such as London, and Paris.

Until you provide us with the evidence, no one is going to agree that this idea is feasible, or even an idea that needs to be more thoroughly investigated.
Oops, that should read, No one knows exactly what the effects on global temperatures would be.
Cyclonebuster, did you read what I just said? You are making false analogies, an illogical fallacy that discredits you and makes your argument weak.

Ill post it again -

Your objective here to is to prove your tunnels create upwelling, not that upwelling weakens hurricanes. Proving that upwelling happens doesnt prove your tunnels create it similar to these humps and mountains you're so fond of. You must use the equations and do the math. Only then will you have proof that your tunnels work.
I can't think of a cat-4 to hit North Carolina. However, South Carolina was hit by Hugo in 1989.
Hazel hit North Carolina as a cat-4. It is the furthest North that a hurricane is known to have made landfall as a cat-4, though ten other hurricanes have made landfall on the North Carolina coast as a cat-3, and there have been several other cat-3 hurricanes further North.
Taken from Wikipedia:

"By October 14, just before reaching the Carolinas, hurricane hunter planes found Hazel's winds to have accelerated to 150 mph"

"Hurricane Hazel is the only recorded category 4 hurricane to strike North Carolina"
Trust you? You havent given us any reason to trust you. Besides you're still not proving your tunnels create upwelling, you just proving upwelling weakens hurricanes; a well known fact.

Please stop trying to prove one argument by providing support for another.
I would like to point out that between the Bahamas and the North Carolina coast it strengthened.
I counted 286 major hurricanes (this number may be off by as many as 5-10 storms, as I was counting them out) since 1851. Of these, only 29 were of cat-5 strength. 5 of these made landfall at cat-5 strength, and only 3 of these landfalls were in the United States. To say that the reason that there has not been a cat-5 hurricane in North Carolina is because of upwelling from the Charleston Bump fails to take into account the rareity of cat-5 storms, the fact that landfalls at cat-5 strength are even more rare, and that there are more factors that contribute to storms weakening than just cooler waters.
And that NC is pretty far north...it's not like the Virgin Islands.
Hazel was a strong category-4 with 150 MPH winds at landfall.
Queensland is not a Territory. It is a State. The Northern Territory, Antarctic Territory, & Australian Capital Territory, are all territories.

According to Wikipedia, TC Larry had estimated sustained winds of 200 km/h (125 mph), not 118 mph. Gusts reached 290 km ph / 180 mph.

"near the town of Innisfail as a major Category 3 hurricane with sustained winds of 118 mph and gusts to 180 mph"

* Cyclone Larry passed directly over the top of the town of Innisfail around 7 am, not 'near'.

* Innisfail is also several miles inland from the coast. More accurate readings of peak winds from Larry, would be obtained from Mourilyan Harbour, South Johnstone, Etty Bay or Cowley Beach, all right on the coast, compared to Innisfail. There were no measurements of sustained winds for TC Larry, but estimates were 200 km/h (125 mph) sustained winds, & peak gusts of 180 mph (290 km ph). The air pressure dropped to 915 mb (<27.17 inHg), which is consistent with a high category 4 or low category 5, on the SSS, not low category 3.

Wikipedia quote:

Due to lack of measurements, Larry's 1-minute sustained wind speeds, either for the storm's peak intensity or from landfall, are not known. It is therefore unknown where on the Saffir-Simpson Hurricane Scale (which is based on 1-minute sustained winds) the cyclone would fall. Larry's wind gusts are generally consistent with a Category 4 storm... The cyclones minimum pressure, however, is more consistent with a Category 5 hurricane.

According to sources I read, (Noaa, NHC), Katrina had a minimum air pressure at landfall of 918 mb, although it was much lower than that (902 mb), when a hundred miles or so, out to sea. I have also seen references that state because Katrina was well above 920 mb when it made a 3rd landfall on the Gulf Coast, that it was only a high cat 3 or low cat 4. Personally, 918 mb would qualify Katrina as a low category 5, in my view. This is not to belittle Hurricane Katrina in any way, which was an horrific event, that claimed 1,600 lives & wrecked NOLA & the Gulf Coast.


The reference to TC Larry being the worst storm since 1931 made by NZ media, is also wrong. The previous worst cyclonic storms in Queensland were in January 1918 (Mackay) & March 1918 (also Innisfail).

Since I last looked at Wikipedia, someone has amended the text, & Dr Jeff Masters might like to set the record straight. Here is the new line he may take exception to:

"(American meteorologist Jeff Masters suggested the storm was more likely a Category 3[6], apparently mistaking 10-minute sustained winds for 1-minute sustained winds.)"

The Wikipedia footnote references are now out of sequence, too. eg [4] is now [5]; [5] is now [6].

Ps: The statistic of "7,000 homeless", was made by the eccentric politician Bob Katter, who is prone to exaggeration. The statistic quoted by the State Emergency Services of Qld, was 6,000 homeless.
This official reading of 200 km per hour at Innisfail, taken at 9 am, would support the Wikipedia statement:


However, the eye crossed Innisfail between about 7am to 7.30am on 20 March, so 200 km ph might not be the maximum wind gust, if the reading was taken at 9am.
PS: 'South Johnstone' is also inland, & south of Innisfail, but still very close to where the eye crossed & could be a useful backup for records, if Innisfail was offline at 7 am. Mourilyan Sugar Mill was destroyed in the cyclone, so records might not be available from there.

Hopefully, records were obtained by BOM from Mourilyan Harbour, Cowley Beach & or Etty Bay. The good news is that the eye crossed 2 or 3 hours before high tide, at around 10 am.