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Cloud Base

Discussion and questions about Cumulus weather station software version 1. This section is the main place to get help with Cumulus 1 software developed by Steve Loft that ceased development in November 2014.
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nking
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Weather Station: W-8681
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Cloud Base

Post by nking »

Hi Steve,

I'm trying to reconcile the cloud base number for my station with that of a nearby Davis station. Is it possible that the Cumulus calculation does not take account of the station height. Mine shows 244 ft , Davis reports 500ft.

I know that you have both stations so you will be able to clarify why there might be such a difference or that I'm being stupid :bash:

I guess that it would make a difference if it's C or F?
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steve
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Re: Cloud Base

Post by steve »

It's could be the fact that Fine Offset stations are poor at humidity. What temperature and humidity are you getting, and what is the Davis site getting? Note that the calculated cloud base is relative to your location, not sea level.
Steve
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nking
Posts: 813
Joined: Thu 17 Dec 2009 2:03 pm
Weather Station: W-8681
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Location: Hurstpierpoint, West Sussex, UK
Contact:
Contact nking

Re: Cloud Base

Post by nking »

Both report 96% humidity Diff between temp and dewpoint 0.6 C the same
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steve
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Re: Cloud Base

Post by steve »

The calculation is 1000 ft for every 4.4 deg F dew point difference. 0.6 deg C = 1.08 deg F => (1.08/4.4)* 1000 = 245 ft. So yours is correct.
Steve
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