A storm is affecting western and central states within the United States. Blizzard conditions are expected to engulf parts of Colorado, Wyoming, Montana, Nebraska and South Dakota, and heavy snow is falling in northern Arizona. Additionally, winds of up to 100mph are forecast across New Mexico, Texas, Kansas and Colorado.

These hazardous weather conditions have led to power outages and travel disruption. A substantial number of flights have been cancelled in the most affected areas, particularly Denver, Colorado. More than 100,000 customers are without power in Texas.

If you are in an affected area or due to travel, you should monitor local media and follow the advice of the local authorities. If you are planning to travel to or from an affected area, you should check with your airline or transport provider before starting your journey. You can check forecasts and weather warnings on the US National Weather Service website. See Natural disasters

Around 3.8 million British nationals visit the United States every year. Most visits are trouble free. Take out comprehensive travel and medical insurance before you travel.

You’ll need prior authorisation to enter the United States using a British passport, either through a visa, a Permanent Resident Card, or the Visa Waiver Programme. Restrictions apply depending on the type of passport you hold, your nationality, criminal history, and countries you may have recently visited. Visa and other entry conditions can change at short notice. It’s your responsibility to know and understand the rules of entry before you travel. See Entry requirements

Terrorists are very likely to try to carry out attacks in the USA. Attacks could be indiscriminate, including in places visited by foreigners. You should monitor media reports and remain vigilant at all times. See Terrorism

UK health authorities have classified the United States as having a risk of Zika virus transmission in Florida, Texas (Cameron County and Hidalgo County only), Puerto Rico and the US Virgin Islands. See Health

You should be alert to the dangers of car and street crime. See Safety and security

Snow storms during winter can cause delays and cancellations throughout airports in the USA. See Natural disasters

If you’re abroad and you need emergency help from the UK government, contact the nearest British embassy, consulate or high commission.