The following symbology is used in our observing forecast, which is provided courtesy of the people at APanel/7Timer.
| Icon | Technical Definition |
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Octet-gram of cloud cover Blue is for clear while white is for cloud. e.g. the “cake” on the left is 0% cloud while the one on the right is 100% cloud. |
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Astronomical seeing From left to right: <0.5″, 0.5″-0.75″, 0.75″-1″, 1″-1.25″, 1.25″-1.5″, 1.5″-2″, 2″-2.5″, >2.5″. In short, the smaller/bluer, the better the seeing condition is. |
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Atmospheric transparency From left to right: <0.3, 0.3-0.4, 0.4-0.5, 0.5-0.6, 0.6-0.7, 0.7-0.85, 0.85-1, >1 (unit: mag per air mass). In short, the fewer bars/bluer, the better the transparency is. |
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Chances of rain/snow |
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Atmospheric instability From left to right: lifted index between 0 to -3, -3 to -5, and below -5. |
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Humid weather warning From left to right: relative humidity between 80%-90%, 90%-95%, and over 95%. |
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Windy weather warning From left to right: sustained wind speed between 8.0-10.8m/s (fresh), 10.8-17.2m/s (strong), and over 17.2m/s (gale or above). |
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