Trixology

WeatherCat => WeatherCat General Discussion => Topic started by: Blicj11 on October 18, 2013, 07:41:24 PM

Title: Current Conditions Calculator
Post by: Blicj11 on October 18, 2013, 07:41:24 PM

I have been experimenting with the Current Conditions Calculator to see if I can set the cloud base parameters to more accurately reflect the actual conditions. It is basically trial and error, but overall, lowering the cloud base parameters seems to be working. One thing that I noticed is that the floating desktop icon for Light Clouds is a partially covered sun. The icon for Scattered Clouds is no sun and all clouds. In fact, the icon for Scattered Clouds is the same icon that is used for Cloudy. This seems counterintuitive to me because the cloud base calculation for Scattered Clouds is a higher number than the calculation for Light Clouds. My online searches indicate there is a definition for Light Clouds but I can't find anything on Scattered Clouds. This begs the question, what is the purpose of the Scattered Clouds parameter in the first place?

I have three questions:

1. Anybody else have any insight to share on changing the cloud base parameters?

2. Any thoughts on the desktop icons being reversed for Light and Scattered?

3. What is the difference between light clouds and scattered clouds?

Thanks.

Title: Re: Current Conditions Calculator
Post by: xairbusdriver on October 04, 2015, 10:19:38 PM

I'm not using the Calculated Cloud Base data. First, I assumed that it required a 'solar' sensor or something that isn't on the standard Vantage Pro2. Now, after reading another part of the Manual (one day, I hope to have read it all! I can then start over and maybe remember 25% of it!), I see that it doesn't even use the output of the Solar Array (assuming that is even available)!

Short of sending up Laser ceilometer (probably costs more than my yearly allowance!) or a ceiling balloon, surely there is a way to use NWS/METAR data, at least in areas near airports offering that kind of data. Of course, in hilly terrain, those altitudes could be much different from hill top to valley...

This is basically good for cumulus clouds, also. Not sure if solid, low overcasts (basically fog above ground level) are classified that way. [blush] OTOH, I suppose the computation method is better (and cheaper) than even a Mark 1 Eyeball pair!

Is this the formula used by WC:

Cloud Base Altitude [ above ground level ] = (((temperature degrees F - dew point degrees F ) / 4.5) * 1000)
or
Cloud Base Altitude [ above ground level ] = (((temperature degrees C - dew point degrees C ) / 2.5) * 1000)

Lots of conversions here or does WC use the correct temperature scale/multiplier/distance unit automatically?