Colour state other than clouds or low visibility (e.g. ice or other obstructions) then the word BLACK is written in full and placed immediately before the actual colour state (e.g. BLACKWHT). The colour state may be appended to a METAR report. A short period forecast called a "TREND" which covers the following two hours from the observation may also be added, often with reference to the colour state. The following criteria are used to determine the colour state: Colour state Colour states is a system used for quickly showing meteorological conditions. Meteorological colour states are determined by the relevant worst condition from
Orange (colour) it contains arsenic and is highly toxic. It was also used as a fly poison and to poison arrows. Because of its yellow-orange colour, it was also a favourite with alchemists searching for a way to make gold, in both China and the West. Before the late 15th century, the colour orange existed in Europe, but without the name; it was simply called yellow-red. Portuguese merchants brought the first orange trees to Europe from Asia in the late 15th and early 16th century, along with the Sanskrit "naranga", which gradually became part of several European languages: "naranja" in Spanish, "laranja"