Tropical cyclone scales

The National Meteorology Bureau of the Imaginary Lands of Nicholas (NMBILN) maintains and enforces a tropical cyclone scale to better forecast and warn the public of a tropical cyclone's intensity and potential impact on land. The scale is heavily based on the Japanese Meteorology Agency and Hong Kong Observatory's Tropical Cyclone Scale. The scale, namely the NMBILN scale, features 6 categories, and classification is based on the maximum sustained wind speed of the tropical cyclone. A 10-minute average is taken for classification purposes.

The NMBILN monitors and makes forecasts for any tropical cyclone developing in the northern hemisphere, between 150°E and 120°W, and this basin is named the Imaginary Lands of Nicholas Basin. This overlaps a significant portion of the Western Pacific Typhoon Basin and the Eastern Pacific Hurricane Basin. However, according to the scale, the name "Typhoon" is used for all cyclones formed in the Imaginary Lands of Nicholas Basin, as opposed to "Hurricanes" (which are normally used east of the International Date Line on 180°W). This is done so in favour of the more densely-populated side of the continent closer to Japan, and the frequency and intensity of tropical cyclones are stronger in the western side compared to the eastern side. Tropical cyclones rarely affect the kingdom's eastern side (closer towards the US).

In conjunction with the NMBILN scale, the Saffir - Simpson scale is also used to conform with the National Hurricane Centre and the Joint Typhoon Warning Centre for the United States.

This system is not to be confused with the Tropical cyclone warning signal, where this system forecasts for the wind speed affecting a particular location and its possible damage, rather than the maximum wind speed of the storm.

Tropical Depression
Tropical Depression (Traditional Chinese: 熱帶低氣壓）, abbreviated as T.D., is designated for storms possessing tropical cyclone characteristics, with centre maximum sustained wind speed rated as "strong" per the Beaufort Scale (41 - 62 km/h). However, it is possible (and has occurred before) for NMBILN to assign a storm the status "Tropical Depression" below this threshold wind speed if NMBILN decides that the storm has "demonstrated sufficient tropical cyclone characteristics". A tropical depression usually lacks an eye, and is just a collection of thundershowers and disturbed weather.

Usually, when a storm is born (and started to become a tropical cyclone), this is the first stage the storm will be classified into (there has been cases where storms are directly classified as "tropical storm" due to implosive intensification). Storms are usually numbered at this stage, starting from 001, based on the number of storms occurred that year. They will remained unnamed (but numbered) until it further intensifies.

Tropical depressions that make direct hit usually will trigger a for the locale.

Tropical Storm
Tropical Storm (Traditional Chinese: 熱帶風暴), abbreviated as T.S., is designated for tropical cyclones with sustained wind speed classified as "Gale" under the Beaufort scale (63 - 87 km/h). This type of storm usually evolves from a tropical depression.

When promoted to this stage, NMBILN will remove its number designation, if any, from the previous tropical depression status, and re-assigns it a name.

Such storm making a direct hit will trigger any type of for the locale, depending on the direction of winds.

Severe Tropical Storm
Severe Tropical Storm (Traditional Chinese: 強烈熱帶風暴), abbreviated as S.T.S., is designated for tropical cyclones with sustained wind speed classified as "Storm" under the Beaufort Scale (88 - 117 km/h). It is the last stage before it evolves into a typhoon given ideal conditions.

Such storm making a direct hit will normally trigger any type of for the locale. However, if the storm appears to be intensifying, or with a sustained wind speed on the higher end of the threshold, a maybe issued.

Typhoon
Typhoon (Traditional Chinese: 颱風), abbreviated as T., is designated for tropical cyclones with sustained wind speed classified as "Hurricane" (> 117 km/h), but under 150 km/h under the revised NMBILN scale of 2009. Prior to 2009, this is the strongest category for tropical cyclones in the basin. Two more categories have since been added.

Typhoon is the equivalent NMBILN category to a hurricane in the Saffir-Simpson Scale, in particular, a Category 1 Hurricane.

A typhoon may or may not have an eye, depending on the condition and the storm's shape. However, when the centre of the storm makes a direct hit over a locale, the locale will typically see sustained winds over 117 km/h, thus triggering.

Severe Typhoon
Severe Typhoon (Traditional Chinese: 強烈颱風), abbreviated as S.T., is designated for tropical cyclones with sustained wind speed between 150 km/h and 184 km/h. This category was added in 2009 to better classify the different intensity and impacts beyond the "typical hurricane" strength. The Chinese name of the category changed from 強颱風 to 強烈颱風 (English translated meaning remains the same), differing from the system used in Hong Kong.

A severe typhoon is the equivalent NMBILN category to a typical Category 2 (or sometimes a very strong Category 1, or a weak Category 3) Hurricane in the Saffir-Simpson Scale.

A severe typhoon of such typically has an eye, and when it crosses over a locale, a almost always is issued.

An example of a severe typhoon was the 2012 Severe Typhoon Chi Wai and Severe Typhoon Kay-Dooblurvay, the latter caused an extensive damage to Nicholas City.

Super Typhoon
Super Typhoon (Traditional Chinese: 超級颱風), abbreviated as SuperT., is the strongest category in the scale, reserved for tropical cyclones with sustained wind speed above 185 km/h. This category was added in 2009 to better classify the different intensity and impacts beyond the "typical hurricane" strength. Rare in nature, a super typhoon can cause a storm surge up to 14 m or above. Typically only one in about fifteen storms will affect the kingdom annually, though there has been records of more. The Chinese name of this category changed from 超強颱風 to 超級颱風 as of 1 August 2016.

A super typhoon is the equivalent NMBILN category to Categories 3, 4, and 5 on the Saffir-Simpson Scale.

A super typhoon of such almost always has an eye, and when it crosses over a locale, a is issued.

An example of a super typhoon was the 2012 Super Typhoon Eigen. It was the deadliest storm, and it had caused devastating damages to Nicholas City, wiping out almost 10% of the city's urban area. The name "Eigen" was later announced by the World Meteorological Organization (WMO) to be retired, and never to be used again, due to the outrageous number of lives it had claimed.