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New Cumulus User

Posted: Sat 06 Jun 2009 6:47 pm
by tonypigott
Hi Steve,

I just downloaded Cumulus last night with the intention of trying it out. I must say that I am very impressed with it. It is an excellent piece of software. I used the Davis VP2 weather station. I have been comparing the Cumulus forecast with the VP2 and WeatherLink forecast; and I must say that I much prefer the Cumulus forecast. I find it more informative and detailed. What time period is the forecast for?

Also, would it be possible to include stability indices within Cumulus?

Once again, congratulations on an excellent piece of software.

Regards,
Tony. :)

Re: New Cumulus User

Posted: Sat 06 Jun 2009 7:19 pm
by steve
tonypigott wrote:What time period is the forecast for?
I believe it's for the next 12 hours.
Also, would it be possible to include stability indices within Cumulus?
You'll have to tell me how to calculate them :)

Re: New Cumulus User

Posted: Sat 06 Jun 2009 9:17 pm
by tonypigott
Also, would it be possible to include stability indices within Cumulus?
You'll have to tell me how to calculate them :)
Hmmmm... I thought it would be useful to calculate them, so as to give an indication of the possibility of thunderstorm activity in the area of the weather station

I have been trying to find the equations for calculation CAPE, etc, from surface weather data. I have been unable at this time to find them. If I find them, I will of course send them on to you. I am afraid that I am only a humble amateur meteorologist/hobbyist. Perhaps someone else knows how to do it. I have only been able to find equations which use upper air data.

Regards,
Tony.

Re: New Cumulus User

Posted: Sun 07 Jun 2009 8:46 am
by apenwith
Hi
Forecasting storms all depends on the upper air instability - back in the days when I did my pilot training (1960's)we used charts called tephigrams which basically compared the temperature at altitude with the heat released by water vapour condensing. After all these years I forget the details - suffice to say surface data alone won't do it.
Regards
Alan

Re: New Cumulus User

Posted: Sun 07 Jun 2009 6:49 pm
by tonypigott
Thank you Alan. I appreciate your reply and help. :)

Regards,
Tony.

Re: New Cumulus User

Posted: Sun 07 Jun 2009 8:04 pm
by steve
I had a recollection of something called a surface-based lifted index, but searching the 'net hasn't come up with anything that makes any sense to me. And I guess it's probably not quite what it sounds like anyway...