::Typhoon2000.com - Tropical Cyclone Sizes

Typhoon2000.com - Tropical Cyclone Sizes

::.. How big is a midget/small/medium/large-sized system?

Tropical Cyclones are measured radially outward from the center to the outermost closed isobar or to the
lowest maximum sustained winds (1 or 10-min ave) of 55 km/hr or 30 knots. This distance, in degrees
(1 degree is approximately 110 km or 60 nm), determines the system's radius size (see table below):

Distance in degrees (°)	Distance in kilometers (km)*	Distance in nautical miles (nm)*	Size / Type	Examples
< 2	< 220	< 120	Very Small / Midget	TY Roke (Auring/2005)
2 - 3	220 - 335	120 - 180	Small	TY Muifa (Unding/2004)
3 - 6	335 - 665	180 - 360	Medium / Average	STY Betty (Herming/1987)
6 - 8	665 - 890	360 - 480	Large	STY Angela (Rosing/1995)
> 8	> 890	> 480	Very Large	STY Nanmadol (Yoyong/2005)

Source: JTWC's FAQ with additional conversion and examples by Typhoon2000.com

*Size of Tropical Cyclone is measured in radius.