Few Thoughts

[emsiwx]

Hello,

Few thoughts to add to Cumulus...?

1. When closing Cumulus SW - add a flag "Station down since ,time," to index.htm and do the last upload?
2. When there is a difference in Avg Wind dir (fluctuating) - add a flag "Variable wind" ?
3. POssibility to set emails and or SMS to send current weather/warnings etc. automatically?
4. Add some weather warnings based on simple algos:

• if DEW POINT before sunset is higher that the avg day temp we can expect Thunderstorm
• if DEW POINT is 17 °C or higher, we can expect Thunderstorm
• if DEW POINT increases by 6 °C in 12 hours, Thunderstorm for sure
• if DEW POINT falls below 0, we can expect night frost
• if DEW POINT falls below 0 and the pressure is low, only light or no frost will develop • if the wind blows from S to W the night frost will be lower by 2 °C • if the wind blows from NW to E and the sky is clear (high press.) night frost will be higher by 2–3 °C
for predecting the night frost, dew point should be measured between 18. and 21. oclock.



if the difference between the avg day temp and the evening dew point is:
1–4 °C expect rain or snow. the lower the difference the heavier precipitation
around 4 °C precip. light
5–8 °C probability for fair weather
> 8 °C windy with showers. Windy weather will come if the dew point is fluctuating

The same for FOG warning - I have seen a nice algo on the Internet, need to llok for it


I have build a simple lightning detector from:

http://www.techlib.com/electronics/lightning.html

and connected it to a PC COM port:

a Maxim IC, the MAX232, is connected to a power source and a few capacitors as recommended in the application notes at the Maxim website but the inputs and outputs are not connected in the standard way. Only the "pulses" output of the lightning detector is connected to the MAX232 pin 11 and the MAX232 pin 14 connects to the RTS of the serial port. That's it for the data lines! Also connect the grounds of the lightning detector, MAX232 pin 15, and the computer (pin 5 on a 9-pin serial port). The power for the MAX232 (pin 16) may be a separate 5 volt power supply, 5 volts from a USB port, or from the CTS pin of the serial port which is set high by the program. Make sure to add a capacitor from the power to ground right at the IC, perhaps a 1 uF. Add a 5 volt zener from pin 16 to ground when using the CTS pin for power since many serial ports output a current-limited 15 volts.

and I have developed a simple app for WIN which reads/counts the lightning strikes, etc.

What about adding it to Cumulus SW? If steve says no, and you will be interested, I can finish my SW.

My SW early TEST/BETA - http://www.emsiwx.info/weather/download/emsiwxlam.exe

BR.

EMSI

[steve]

1. When closing Cumulus SW - add a flag "Station down since ,time," to index.htm and do the last upload?

Yes, I like that (as an option).

2. When there is a difference in Avg Wind dir (fluctuating) - add a flag "Variable wind" ?

I'm not sure how that would work, or what it would actually mean. Typically, the Fine Offset wind vanes are constantly 'variable', or so it seems to me.

3. POssibility to set emails and or SMS to send current weather/warnings etc. automatically?

Yes, definitely, this is something I've had in mind for while now.

4. Add some weather warnings based on simple algos:

Yes, quite possibly. Some thought would be needed on the algorithms, some of the ones you've quoted certainly don't apply here. I already get complaints about the forecast saying rain when it's (currently) dry! And giving a cloudbase figure when the sky is clear.

Cumulus is really software for recording the output of a weather station. I'm not sure I want it get too far away from that. Of course, there's no reason someone couldn't write an add-on. Perhaps I could provide a facility for plug-ins...

I have build a simple lightning detector from:

I'm happy to look at supporting sensors like this (and the sunlight recorder, as another example). I just can't commit to when I'll be able to add it. Cumulus 2 still needs a lot of work before it even does the same as version 1.