The recently-launched Twitter Alerts service, which allows emergency services to send out urgent messages to Twitter users, has expanded rapidly in recent weeks as the UK has experienced the worst weather since the 1700s.

Twitter has announced today the following:

In times of crisis, it is important for emergency services to be able to deliver critical information to the public as quickly as possible.

And as the UK faces severe, repeated weather and flood warnings, we’ve been working with those services to ensure that Twitter is as useful as possible to those on the front line.

Today we are pleased to welcome 38 UK fire brigades to the Twitter Alerts programme, giving them more tools to help deliver critical information to the public in times of crisis.

Twitter alerts works by offering urgent comms from pre-registered emergency services:

Twitter users can sign up to receive Twitter Alerts from any participating account. When that account Tweets with an emergency message, users receive an SMS or push notification directly to their phone.

Twitter Alerts are also designed to capture users’ attention, with the orange bell standing out from other Tweets on followers’ Timelines and across twitter.com, as well as the Twitter mobile apps. They are also marked with the hashtag #alert.

Making use of push messages on Twitter users' phones we think is a major step from taking Twitter from social to crucial in terms of keeping users connected. We hope to see more uses of social media in this way for broadcast communications.