Onboard weather station

[Wallaby]

I am interested in finding out what others have done to set up a personal weather station on their boats, in particular plotting barometric pressure.


On a recent trip (100 miles offshore, in the Gulf Stream) I ran in a major storm. It wasn't without warning. I watched on Nexrad radar updates on Sirius Weather as a long line of thunderstorms from Florida coalesced into a single mass, over 80 miles wide and 50 miles deep. Nexrad gave no speed or direction for the new storm. During the day, other storms had dissipated about 50 miles offshore. This one grew dramatically in intensity and speed. In 55 years of sailing I've never seen anything like it.


It quickly dominated the horizon as two layers, the upper like a 'white hook', the lower layer uniformly grey. There were no indications of high winds in the cloud formation, however, the rapid approach said otherwise. I had time to completely furl the jib and put two reefs in the mainsail. A third reef would've been nice. There wasn't time given that my third reef uses a messenger line on the leech.


FYI, the initial gusts were 78 knots, dropping to 40-60 knots. Waves were low (4-6 feet), but often breaking. My boat handled the conditions so well I did not need to heave to.


Checking the barometer in the cabin might've been helpful is determining the intensity, but not possible given the rate of change in the conditions. Having a barometer at the helm showing the rate of change, that would be ideal.

[conachair]

Originally Posted by Wallaby

I am interested in finding out what others have done to set up a personal weather station on their boats, in particular plotting barometric pressure.

One of these connected to a Raspberry Pi running openplotter >


gives you this >



Then read the barometer handbook and modern marine weather by David Burch. Then read them both again

[GordMay]

Smart Phone Barometer?
➥ https://www.howtogeek.com/254603/how...-or-altimeter/

[Bill O]

Originally Posted by conachair

One of these connected to a Raspberry Pi running openplotter >


gives you this >



Then read the barometer handbook and modern marine weather by David Burch. Then read them both again

We have a barometer chip in our Pi and do not have an alarm on it to detect when a quick /specific fall rate. It was my understanding that one would need to go through WatchDog to set up an alarm and not certain one can set different fall or rise rates to trigger the alarm.


Really haven't looked into it that much after we set up Plotter since we already had a weather station on board with a settable fall/rise rate with an audible alarm. We installed the Davis Vantage Vue years ago as a back up wind sensor (speed/direction) which included the bonus rain and barometer sensors. The barometer alarm has saved our bacon a few times for quick pop up storms, but does take some experience to distinguish a storm from the normal daily afternoon fall. It is easier to shake out an unnecessary reef than to get caught w/your pants down.


Maybe the barometer options to trigger an alarm have now been added in the latest versions of WatchDog (since last year), but if not it would be a nice upgrade.


Bill O.

[flyingnut40]

Originally Posted by Bill O

We have a barometer chip in our Pi and do not have an alarm on it to detect when a quick /specific fall rate. It was my understanding that one would need to go through WatchDog to set up an alarm and not certain one can set different fall or rise rates to trigger the alarm.


Really haven't looked into it that much after we set up Plotter since we already had a weather station on board with a settable fall/rise rate with an audible alarm. We installed the Davis Vantage Vue years ago as a back up wind sensor (speed/direction) which included the bonus rain and barometer sensors. The barometer alarm has saved our bacon a few times for quick pop up storms, but does take some experience to distinguish a storm from the normal daily afternoon fall. It is easier to shake out an unnecessary reef than to get caught w/your pants down.


Maybe the barometer options to trigger an alarm have now been added in the latest versions of WatchDog (since last year), but if not it would be a nice upgrade.


Bill O.

I'm building one of these.


http://www.instructables.com/id/Weat...Display-for-Se

Dennis

[Bill O]

Originally Posted by flyingnut40

I'm building one of these.


http://www.instructables.com/id/Weat...Display-for-Se

Dennis

Dennis,
Looks good. Would be nice if you could write the programming for an audible alarm for fall/rise rates for storm/heavy wind warning. We like it as you aren't always watching the monitor and can't be that precise to determine specific fall/rise rates.


Similarly one could buy a chip and mount it on a Pi


Bill O.

[Dockhead]

Maretron DSM250 fed with wind, temp, baro, and humidity data from a WSO100 over the boat network. With compass data, it will display ground wind.

Barograph is a crucially important instrument in my opinion. There are probably a hundred ways to do it, but one way or another, it should be done.

[Bill O]

Originally Posted by Dockhead

Maretron DSM250 fed with wind, temp, baro, and humidity data from a WSO100 over the boat network. With compass data, it will display ground wind.

Barograph is a crucially important instrument in my opinion. There are probably a hundred ways to do it, but one way or another, it should be done.

Yes, agree the weather info is critical and as previously mentioned the data graphically displayed in OPlotter through the Pi chip, but does not have settable fall/rise rates for alarms. We hoped the Pi chip would be a backup to our Davis weather station which has lots of alarm settings including several fall/rise rates.
There are no barometer settings in latest ocpn 5.0 Watchdog, but can see there is a barometer update in Sean's github Watchdog_pi. I need to take a look at his barometer updates to see what was added.


Bill O.

[flyingnut40]

Originally Posted by Bill O

Dennis,
Looks good. Would be nice if you could write the programming for an audible alarm for fall/rise rates for storm/heavy wind warning. We like it as you aren't always watching the monitor and can't be that precise to determine specific fall/rise rates.


Similarly one could buy a chip and mount it on a Pi


Bill O.

It would likely be only a few lines of code. You might consider contacting the person about adding the feature. Im ok building and installing code..... writing/ modding.... not so much.

I have a lightning detector module that looks pretty cool. It can detect distance, approach or retreat and whether it is sky to ground or cloud to cloud.

Now, if I can get help with the code.....

Dennis