Apparently the Early Warning Network, a once-free service in my area that gives warnings about severe weather and other incidents by email and SMS, will now be charging an annual subscription fee for SMS alerts. Since email alerts are free, however, and since I can get email on my phone whenever I have phone service, I think I'll be okay with email-only alerts.
They also have mobile phone apps ($4.95) that will tell you if you enter an area with a current alert. It's not clear from the website whether this also allows you to get alerts for free that are very similar to the SMS system, or if they allow you to set up points of interest (say, your house and place of business, houses of close family) to get alerts for them when you are currently far from there.
I wish we'd had a similar service back when The Storm hit, as I've mentioned before, but sometimes I've found the warnings to be erring on the side of over-cautious. Sometimes a warning means storms, sometimes it just means light rain, though that's probably just when we're further from the epicentre.
Mokalus of Borg
PS - I do recommend the system.
PPS - But it's up to you whether you're willing to pay for SMS alerts.