InReach requires you to text a number first before you can receive messages from them.
This tool allows you to receive alerts, and forward them to your InReach device.
There is quite a bit of cleanup that should happen. I had an urgent need for this, and it had a tight deadline. This program worked for me need, but it's code quality is a reflection of the tight deadline.
@hajekr has a bot for notifying you about the aurora. I learned about the form submit trick from their project. This saved me a lot of pain because getting a dedicated 10-digit phone number for SMS from Twilio or AWS seemed too complicated for the USA.