2012/08/25

A little background first...

   Beginning with the next post, I'll be providing a summary of all the tropical cyclones currently active. Sometimes I might also identify a region I feel has potential for development. These areas will not be regions identified by the major weather agencies, so don't put too much weight on them. To date my success ratio is about 50/50. As for the official storm summaries, most of the data will be sourced from either NOAA's National Hurricane Center (NHC), if the system is in the Atlantic or Eastern Pacific, or the U.S. Navy's Joint Typhoon Warning Center (JTWC) for everywhere else. The world's oceans are divided into several basins that are semi-isolated regions for tropical cyclone development.

Tropical Cyclone basins of the world, along with the abbreviations I'll be using
   Note that these divisions are not absolute. For example, NOAA divides the NEPac in two, with the NEPac basin extending from North America to 140°W, then the Central Pacific basin covers the region between 140° and 180°. I choose not to use this convention because there are very few storms that form in the central Pacific. Also, I have seen many different methods of dividing the SInd from the SPac, but 135°E is used by the JTWC and it makes sense for most applications. Another potential source of confusion is tendency for some weather agencies to split the SInd in two, I'll be ignoring this convention as well since quite a few storms do travel across that basin. Finally, although the South Atlantic is defined in the diagram, that region is a virtually void of storms; only a handful of tropical cyclones have formed there, and only one reached hurricane strength.
   The classification of tropical cyclone intensity that I'll be using is the Saffir-Simpson Hurricane Wind Scale , which is likely the most widely used scale. Although the scale was initially developed based on North Atlantic (NAtl) storms, it essentially can be applied worldwide. Most storms, or regions that may become storms, are first listed as areas of investigation and are labeled as INVEST followed by an identifying number and basin tag. Upon becoming sufficiently organized, the system will be upgraded to a Tropical Depression (TD) and receive a different number. When a TD's maximum sustained winds reach 35kts, it is reclassified as a Tropical Storm (TS) and given a name. At 65kts the storm is considered to be at hurricane strength, although the term hurricane is just one of several terms used for this intensity. The following table summarizes these classifications as well as the basin specific terms. It is important to remember that all the wind speeds I list will be the average over one minute, as apposed to ten minute averages that some other agencies use.
 
Intensity (kts) INVEST < 35 35-60 65-80 85-95 100-110 115-125 130-130 > 135
Natl 9*L
Tropical
Depression
(01L and up)

 
Tropical Storm: named by NHC Hurricane-1 Hurricane-2 Hurricane-3 Hurricane-4 Hurricane-5
Major Hurricane
NEPac 9*E
Tropical
Depression
(01E and up)

 
Tropical Storm: named by NHC Hurricane-1 Hurricane-2 Hurricane-3 Hurricane-4 Hurricane-5
Major Hurricane
NWPac 9*W
Tropical
Depression
(01W and up)

 
Tropical Storm: named by
JMA (Japan Metrological Agency)
Typhoon-1 Typhoon-2 Typhoon-3 Typhoon-4 Typhoon-5
  Super Typhoon
Nind 9*A(or)B
Tropical
Depression
01A/B and up

 
Tropical Storm: named by IMD
 (India Meteorological Department)
Cyclone-1 Cyclone-2 Cyclone-3 Cyclone-4 Cyclone-5
Sind 9*S
Tropical
Depression
(01S and up)

 
Tropical Storm: named by
 France or Australia
Cyclone-1 Cyclone-2 Cyclone-3 Cyclone-4 Cyclone-5
SPac 9*P
Tropical
Depression
(01P and up)

 
Tropical Storm: named by
 Australia, New Zealand, or Fiji
Cyclone-1 Cyclone-2 Cyclone-3 Cyclone-4 Cyclone-5
 

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