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FAQ: Difference between revisions
How is my rain rate calculated?
(How is my rain rate calculated?) |
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==How does Cumulus know the height of the cloud base?== | ==How does Cumulus know the height of the cloud base?== | ||
It doesn't. It uses a calculation which gives the theoretical height above ground level at which Cumulus clouds might form, based on the current temperature and dew point. It assumes that the difference between temperature and dew point decreases by about 4.4 degrees Fahrenheit per 1000 feet increase in altitude. When the two values coincide, the air is saturated (relative humidity = 100%) and Cumulus clouds may form. | It doesn't. It uses a calculation which gives the theoretical height above ground level at which Cumulus clouds might form, based on the current temperature and dew point. It assumes that the difference between temperature and dew point decreases by about 4.4 degrees Fahrenheit per 1000 feet increase in altitude. When the two values coincide, the air is saturated (relative humidity = 100%) and Cumulus clouds may form. | ||
==How is my rain rate calculated?== | |||
For stations which supply a rain rate, Cumulus uses that. For stations which don't supply a rain rate (e.g. Fine Offset and La Crosse), Cumulus simply takes the rain total from the last five minutes and calculates a rate based on that; e.g. 0.3mm in 5 minutes is a rate of 3.6mm/hr. | |||
=Troubleshooting= | =Troubleshooting= | ||