Thunderstorm Warning Signals are graded into four levels: blue, yellow, orange and red.
a)Thunderstorm Warning Blue Signal
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Meaning: It may be affected by thunderstorms within 6 hours. Wind gusts are expected with a wind force greater than 7 scale (50-61 km/h), accompanied by lightening.
Or, it is affecting by thunderstorms. Wind gusts with a wind force between 7 and 8 scale (50-74 km/h) are blowing accompanied by lightening , and are likely to continue.
b)Thunderstorm Warning Yellow Signal
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Meaning: It may be affected by severe thunderstorms within 6 hours. Strong wind gusts are expected with a wind force greater than 9 scale (75-88 km/h), accompanied by strong lightening.
Or, it is affecting by severe thunderstorms. Strong wind gusts with a wind force between 9 and 10 scale (75-102 km/h) are blowing accompanied by strong lightening , and are likely to continue.
c)Thunderstorm Warning Orange Signal
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Meaning: It may be affected by very severe thunderstorms within 2 hours. Very strong wind gusts are expected with a wind force greater than 11 scale (103-117 km/h), accompanied by very strong lightening.
Or, it is affecting by very severe thunderstorms. Very strong wind gusts with a wind force between 11 and 12 scale (103-133 km/h) are blowing accompanied by very strong lightening , and are likely to continue.
d)Red Thunderstorm Warning Sign
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Meaning: It may be affected by extreme severe thunderstorms within 2 hours. Extreme strong wind gusts are expected with a wind force greater than 12 scale (118 km/h), accompanied by extreme strong lightening.
Or, it is affecting by extreme severe thunderstorms. Extreme strong wind gusts with a wind force of 12 scale (118 km/h) or greater are blowing accompanied by extreme strong lightening , and are likely to continue.
