What you would need
Keep a spare phone charger, medication, glasses, torch, blankets or warm clothing in case you're stranded or need to stay overnight in temporary accommodation.
Make copies of passports, insurance and financial documents. Keep them somewhere safe where you can access them quickly without putting yourself at risk. Most libraries have a photocopier you can use.
Where to get information
In most emergencies, the advice is to stay inside and tune into your local radio station for information.
BBC Three Counties Radio is on 95.5 FM, 103.8 FM or 104.5 FM.
Make sure you have spare batteries or a wind-up radio in case of a power cut.
You can also visit Hertfordshire Constabulary or call 101 for information from emergency services.
Where you could stay
The council may arrange a community or leisure centre for you to stay, but you might be more comfortable with family or friends.