In Burma (or Myanmar), the climate is generally tropical, with a rainy season from mid-May to October due to the southwest monsoon, a cool and dry season from November to mid-February, and a hot pre-monsoon season from mid-February to the beginning or the middle of May.

In addition, there are mountainous areas, with a mild or cool climate, but also a portion of the Himalayan range in the far north, which is very cold, at least at high altitude.

The rains in the monsoon season are plentiful along the coast, and are usually abundant on the mountain slopes, while in the interior, the monsoon penetrates with more difficulty, so much so that some inland valleys and plains are almost arid.

The sun in Burma shines regularly in the dry season, while in the rainy season it is rarely seen.

Winter, from mid-November to mid-February, is relatively cool in the center-north, while it is hot in the south. The weather is mostly sunny and warm in the daytime, but sometimes, cool air masses from China may lower the night temperatures almost to the freezing point in the north, to about 5 °C (41 °F) in the center-north, to 8/10 °C (46/50 °F) in Yangon and on the north coast, and to 12/15 °C (54/59 °F) along the south coast.

In winter, the biggest differences are recorded: the average daily temperature in January is 18 °C (64 °F) in Myitkyina, 20 °C (68 °F) in Mandalay, 21.5 °C (71 °F) in Sittwe, which is located on the northern coast (overlooking the Bay of Bengal), 25 °C (77 °F) in Yangon, and 26 °C (79 °F) along the south coast. So, winter is hot and summer-like only from the area of Yangon (or Rangoon), the former capital, and the beaches of Chaungtha and Ngwesaung.

In the pre-monsoon period, from mid-February to the beginning or the middle of May, the weather remains sunny, but the temperature gradually rises, and in mountainous areas, there can be some atmospheric instability in the afternoon, with the first thunderstorms. It's the hottest time of the year throughout Burma, especially in valleys and inland plains, where the heat becomes unbearable, and locals eagerly await for the arrival of the monsoon. The temperature can reach 37/38 °C (99/100 °F) along the southern coast, 40 °C (104 °F) in Yangon, and up to 43/45 °C in Mandalay and inland areas. Typically, April is the hottest month, in addition to the first part of May, before the monsoon comes.

On the coasts (both the the north coast overlooking the Bay of Bengal and the south coast overlooking the Andaman Sea), it doesn't get that hot in the pre-monsoon season, both because of the thermal inertia of the sea and because the monsoon rains arrive earlier.

The monsoon season is less hot: the maximum temperature drops to around 28/29 °C (82/84 °F) on the coasts, to 30 °C (86 °F) in Yangon, and to 33/34 °C (91/93 °F) in Mandalay, but the heat is sultry and the sky is often cloudy. The monsoon arrives first on the southernmost coast of the Andaman Sea (see Tavoy, Kampong Ulu, Mergui Islands), around May 10-15, and it is very intense from the beginning, so much so that more than 400 millimeters (16 inches) of rain fall in this month. In Yangon, the monsoon arrives between May 20-25, in Mandalay (where, however, its effects are more limited) between May 25 and June 1, and finally, it arrives in the far north between the first and the 10th of June.

The rainiest months are almost everywhere June, July and August, and on the two coasts, being exposed to the west, the rains are plentiful; in fact, some areas receive more than 1,200 mm (47 in) of rain in a month! Yangon is a bit less rainy because it's located in the area of the mouths of the Irrawaddy River, which are exposed to the south, and receives about 500/600 mm (20/23.5 in) of rain per month during this period, while the central area where Mandalay is located receives only 100/150 mm (4/6 in) of rain per month.

In September, rainfall decreases a bit, except in the extreme south, while during the month of October, the monsoon withdraws, starting from the north; the monsoon is replaced by drier and gradually cooler winds, which blow from the north or northeast.

As mentioned, the monsoon particularly affects the coasts, which are exposed to the southwest winds. So, this is the wettest area of Burma, so much so that the amount of rainfall reaches 5,000 mm (195 in) in a year (or rather, in the rainy season, since in the rest of the year, the rains are very poor or absent here as well).

By contrast, in the central plains, precipitation drops below 900 mm (35.5 in) per year, as happens in Mandalay, Myngyan, Magway, and Bagan, the ancient capital of many Burmese kingdoms. At the foot of the mountains and on the slopes, the monsoon rains are instead plentiful, and during the wettest periods, there may be landslides and floods.