The climate can generally be described as tropical. As the country is affected by monsoon, it is hot and humid with an overage temperature around 27.C (80.F). There are two distinct seasons: the Rainy Season and the Dry Season. However, the Dry Season is divided into two sub-seasons, cool and hot. These seasons are:

The Rainy season:
From June till October 27-35.C (80-95.f)

The Dry season (cool):
From November till February 17-27.C (80-95.F)

The Dry season (Hot) :
From March till May 29-38.C (84-100.F)

Most Cambodians dress up casually except when they are attending formal events. It is common to see men and women using Krama, a Long, Narrow checked cotton cloth round their neck. The krama is just like a piece of clothe. Lightweight, loose-fitting, cotton clothing is recommended and long-sleeved items should be included for protection from mosquitoes and the sun. During the rainy season an umbrella is more convenient than a rain coast. A jacket may be needed in hotels and restaurants using excessive air-conditioning.

Trains are available only from Phnom Penh to Battambang Province, and depart from Phnom Penh about 5AM or 6AM with the trip taking almost the whole day.

Drink lots of water. Never drink tap water purified, bottled water is available everywhere. 

Use an insect repellent against mosquitoes. It is the only way to be sure of protection against mosquito borne diseases. Since Cambodia has a hot and humid tropical climate, casual and light-weight clothing is best. Clothing made from natural fibers is the best option. A jacket might be needed on cool winter evenings or in hotels and restaurants using excessive air-conditioning. A hat and high-factor sun block is advisable as protection against the hot sun when sightseeing.

US dollars are as commonly used as the Cambodian Riel and even Thai Baht is acceptable in many places. Most hotels and many restaurants and shops set their prices in dollars. Small transactions are usually done in Riel. Always carry some small Riel for motorcycle taxis, snacks, beggars and other small purchases.

Riel notes come in 50, 100, 200, 500, 1000, 5000, 10,000, 50,000 and 100,000 denominations, but the distinctive red 500 Riel note is the most commonly used.
Please click here for the exchange rate with your own currency.

Credit cards and travelers checks are not common but are catching on. US dollar travelers checks are much more easily encashed than any other kind.

Money changers cluster around the markets. When accepting money, inspect the bills. Marred Riel is acceptable tender, but the tiniest tear in a large US note renders it worthless.

There are banks in all of the larger provincial capitals, including Phnom Penh, Siem Reap, Sihanoukville, Battambang. Banks can change money, effect telegraphic transfers and some banks can cash travelers checks and accept Visa cards.

There is only two ATM in Cambodia, at the Canadia Bank in Phnom Penh and ANZ Royal Bank in Phnom Penh, and you must have a local account in order to use it. You cannot access foreign accounts from this.

A passport and visa are required. Tourists and business travelers may purchase a Cambodian visa valid for one month at the airports in Phnom Penh and Siem Reap. Both require a passport-sized photograph. A departure tax is charged on all domestic and international flights.