James88
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What actually defines a direct hit on a location by a hurricane? I've just seen some archives on Hurricane Allen:-
"The center of Allen did not cross land at any location until it moved inland north of Brownsville, Texas. It did a remarkable job of 'broken field running' through the Caribbean at speeds of 15-20 knots. The eye passed between Barbados and St. Lucia, Haiti and Jamaica. It then passed north of the Cayman Islands, and between Cuba and the Yucatan peninsula."
I did think at first that a direct hit was when the eye actually passed over a location, but then I found that the eye of Hurricane Fabian last year didn't actually pass directly over Bermuda, but it still registered as a direct hit. So what does define a direct hit?
Thanks
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LI Phil
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I'm not sure this is the be all and end all answer, but I believe a "brush" means the hurricane came within 60 miles of any location. Anything closer would be a direct hit. If this answer is not correct (HF, ED, JK, help me out), please let me know.
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James88
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Cheers, Phil. From what I've seen with past hurricanes, 60 miles seems about right. I guess (depending on the size of the storm) that this would mean if the eyewall gets near to a location, it's a direct hit.
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LadyStorm
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I once read that the Southern Hemisphere does not have Hurricanes or Typhoons. I am planning on moving to New Zealand, wondering if this is true. I also have heard that Austraila gets them. Has me confused, does anyone have any specifics on this? 
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MikeC
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The northern coast of Australia most definitely gets Tropical Cyclones, and sometimes big ones. Luckily most of that part of Australia isn't all that inhabited. Northeast and West Australia also get storms as well. I believe New Zeland is mostly free of them due to its more southerly latitude -- at least the big ones.
Thinking of Oz, probably Tropical cyclone Tracy is the big one there. It hit Darwin (on the northern coast of oz) pretty hard in 1974. At least that's the one brought up to me the most when I was talking with folks while I was in Sydney.
When you hear of no southern hemisphere storms, I believe they are talking about the South Atlantic. But that was blown out of the water by this years anomoly storm that hit Brazil. Needless to say, tropical systems in the South Atlantic all but never occur.
Edited by MikeC (Fri Jun 11 2004 12:06 PM)
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LI Phil
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Perhaps this will help...btw, Mike C, good response.
How often is New Zealand hit by tropical cyclones?
by Mark Sinclair
"Recent NIWA research shows that northern New Zealand is hit by an average of a little over one storm of tropical origin each year. The severity of these storms depends on their location and on the phase of the El Niño/La Niña cycle.
Every year between December and April, storms from the tropics move south toward New Zealand. As these tropical cyclones advance poleward, they eventually lose characteristic hurricane features such as the eye and the surrounding symmetric cloud and precipitation region and progressively acquire the asymmetric cloud and thermal features more typical of a frontal mid-latitude storm. Scientists use the term transition (ET) to refer to this poleward movement and accompanying structure changes.
As these storms move into New Zealand waters, they often maintain sufficient vigour to produce damaging winds, high seas and heavy rain. Occasionally, tropical cyclone remnants re-intensify in the extratropics to become potent mid-latitude storms capable of inflicting loss of life and severe property damage.
Several memorable ET events have occurred in the New Zealand region. In April 1968, Tropical Cyclone Gisele re-intensified as it moved south over New Zealand, producing winds gusting to 75 m/s (270 kph) in Wellington, and sinking the interisland ferry Wahine with the loss of 51 lives. Cyclone Bola dumped over 900 mm of rain and produced hurricane-force winds in regions of northern New Zealand in March 1988. More recently, Cyclones Fergus and Drena brought torrential rain and storm-force winds to the North Island in December 1996, triggering an exodus of summer tourists from coastal resorts.
Cyclones near New Zealand
Frequency by month of tropical cyclones progressing south of 35°S from 1970–1997 data. The total number of storms was 81.
In the Tasman Sea, west of New Zealand, average storm motion is only about 5 m/s due south. On the other hand, east of New Zealand, tropical cyclones move away to the south-east at speeds exceeding 8 m/s. Average tropical cyclone intensity is greatest near latitude 20–25°S, indicating that most storms moving into New Zealand waters are weakening. Storms that undergo ET in the Tasman Sea are more vigorous than those east of New Zealand.
The largest numbers of tropical cyclones make it into middle latitudes (south of 35°S) in February and March. If we compare these events with overall cyclone numbers (which also peak in February), we see that March is the month during which the greatest fraction of storms will take a track into middle latitudes. Put another way, this means that, given a tropical cyclone, it is most likely to move south of 35°S in March. This corresponds to the time of warmest sea temperature, a factor that scientists have shown to be essential for tropical storm survival.
An connection
The location and intensity of ET is also affected by the phase of the El Niño–Southern Oscillation (ENSO) cycle. During El Niño years, tropical cyclones enter middle latitudes anywhere between the Australian coast and about 150°W and typically weaken quickly as they move away to the south-east.
During La Niña years, ET is largely confined to longitudes west of the dateline (longitude 180°). These storms move more slowly toward the south and tend to retain their vigour for longer. Interestingly, the strongest storms appear to affect New Zealand when the cycle is between El Niño and La Niña."
LI Phil
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James88
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I think that earlier this year Cyclone Ivy passed nearby New Zealand as a weakening tropical storm. If the average holds true, that should be it for New Zealand until 2005.
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LI Phil
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Well, their season is December-April, so they might get one towards the end of this calendar year, but it would be the next cyclone season.
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2005 Forecast: 14/7/4
BUCKLE UP!
"If your topic ain't tropic, your post will be toast"
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LadyStorm
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Loc: United States
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Thanks to everyone for your excellent responses. I am forever grateful. Looks like I won't be doing much weather watching over there. Thats okay, I can still watch out for Florida. I will be out of harms way.......:) You guys are great!!!!
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"The significant problems we face cannot be solved at the same level of
thinking we were at when we created them"
..........Albert Einstein
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