User guide 16: Weather alerts on MeshCore

Email and push notifications both need the internet. In a big storm that is exactly what goes first: the power drops, the NBN box goes dark and the phone towers run out of battery. MeshCore keeps working.

MeshCore is a free radio mesh. Small battery radios pass short text messages to each other, hop by hop, with no internet and no phone network. We run a repeater on a roof in Dayboro, and our weather station posts its warnings into the mesh. If you have a MeshCore radio in range, you get them, power or no power.

This guide is for people who already have, or are about to get, a MeshCore radio. You do not need to be a member, the mesh is open to everyone.

What gets posted

We post to a dedicated channel called #4520-4521-weather-alerts, for the 4520 and 4521 postcodes. Only warnings and all clears go there. There is no chatter, no daily forecast and no replies, so you can leave its notifications on without your phone buzzing all day.

A warning goes out when one of these starts:

• Lightning within 50 km of Dayboro
• Damaging wind at our weather station
• Very heavy rain on the way, from our rain nowcast
• A creek crossing closing
• A Bureau of Meteorology warning that covers our part of Moreton Bay

An all clear follows once it has been quiet for a while. A warning is never repeated while it lasts.

Mesh messages are short, so a warning is one line. It looks like this:

⚠ Dayboro WARNING 15:42 | (what is happening) | All clear will follow | dayboro.au
✅ Dayboro ALL CLEAR 17:05 | (what has ended) | dayboro.au

If several things start at once and they do not fit in one line, the line ends with “+2 more, !warning”. Send !warning on #weather to get the full picture (see below).

To keep the mesh usable for everyone, we send at most one post every 10 minutes and no more than 8 warnings a day. The same warnings also go out on the busier #weather channel.

What you need

• A MeshCore companion radio. A small LoRa radio flashed with MeshCore companion firmware, which talks to your phone over Bluetooth or USB. Ask on the local mesh groups which models people around Dayboro are using.
• The MeshCore app on your phone, version 1.28.0 or newer. Joining hashtag channels came in 1.28.0. Update the app first if yours is older.
• Range to the mesh. From most of Dayboro and the 4520 area you will reach a repeater. In a deep gully you may need the radio near a window or up high.

Keep the radio charged. A radio with a flat battery is no help when the power is out, so a small solar panel or a power bank is worth having.

Step 1: Connect the app to your radio

Open the MeshCore app and connect to your companion radio, as you did when you set it up. You should see your contacts and your channel list.

Step 2: Add a new channel

Go to your channels and choose to add a channel. Pick the option for a hashtag channel (a public channel joined by its name). Do not pick a private channel, that one needs a secret key and will not get our posts.

Step 3: Type the channel name exactly

Type the name exactly as shown, all lower case, with hyphens and no spaces (the app only allows letters, numbers and hyphens):

#4520-4521-weather-alerts

This matters more than it looks. A hashtag channel’s secret is made from its exact name, letter for letter. #4520-4521-Weather-Alerts with capitals is a completely different channel and you will hear nothing on it. The same goes for an underscore instead of a hyphen, a space, or a missing #.

Or scan this code instead

If your app is version 1.47.0 or newer, you can skip the typing. Choose Add channel, then Scan QR, and point the camera at this code. The app fills in the name and the channel key for you, so there is no way to get the spelling wrong.

The same code is in the footer of every dayboro.au page, so you can also open the site on a laptop and scan it from your phone.

Step 4: Save and check it is in your list

Save the channel. It now shows in your channel list next to the ones you already have.

The channel stays quiet until there is something to warn about. On a fine week you will see nothing, and that is how it should be. Do not post in it yourself, please, so it stays clean for everyone.

Step 5: Leave notifications on for this channel

Make sure your phone lets the MeshCore app show notifications. If the app lets you mute channels one by one, mute the busy ones and leave #4520-4521-weather-alerts on. It only speaks when it matters.

Ask for the weather yourself on #weather

The alerts channel does not answer questions. For that, use #weather (add it the same way if you have not got it), or send a direct message to our station.

Other postcodes on !weather are left to the other weather bots on the mesh.

Troubleshooting

• Nothing has ever come through. That may simply mean there has been nothing to warn about. Send !weather on #weather. If you get a reply, your radio reaches us and the alerts channel will work too.
• No reply on #weather either. You may be out of range. Try the radio higher up or near a window, and check it shows a repeater nearby.
• Others got a warning and I did not. Check the channel name letter for letter, all lower case. Delete the channel and add it again if unsure.
• I cannot find the hashtag channel option. Update the MeshCore app. Hashtag channels need version 1.28.0 or newer.
• Messages arrive late. A mesh passes messages hop by hop and they can take a little while, especially when it is busy. That is normal.

Use it alongside push and email

MeshCore is the backup that works when everything else is down. Members can also pick their own storm distance and get warnings on their phone, by email and, for paying members, by text. See User guide 14: Set up push notifications and User guide 15: Storm warnings by email and text.

Lightning detection can miss strikes, and a mesh message can be delayed. If you can hear thunder, you are close enough to be struck, so head inside.