Do you need to know, when is the best time to go to Kalimantan? Then you should take a look here, what weather you can expect there during the year.
Kalimantan is part of Indonesia. The climate of Indonesia is tropical. You can expect hot and humid weather, but more moderate weather in highlands. Temperatures remain fairly constant throughout the year, they are higher at the coast and a little bit lower in the inland.
When speaking about the usual weather in this area, the information is relevant for example for these popular places: Amuntai, Apo Kayan, Balikpapan, Banjarbaru, Banjarmasin, Barabai, Bontang, Central Kalimantan, Derawan, East Kalimantan, Gunung Palung National Park, Kandangan, Kotabaru, Kumai, Loksado, Martapura, Nagara, Nunukan, Palangka Raya, Pangkalan Bun, Pontianak, Samarinda, Singkawang, South Kalimantan, Tanjung Puting, Tarakan, West Kalimantan.
Let's look now what weather you can expect in the area around Pontianak and in many other cities. The warmest month here is June, the average maximum temperature is 34 ℃ (93.2 ℉). The average minimum temperature in this month is 22.9 ℃ (73.22 ℉). The coldest month here is October, the average maximum temperature is 32 ℃ (89.6 ℉). The average minimum temperature in this month is 22.8 ℃ (73.04 ℉). The most rainy month here is October, the average number of rainy days is 27.5. The least rainy month here is February, the average number of rainy days is 13. 
When travelling around Kalimantan, always consider the altitude of the the place as well. We should remind you, that the highest point in Indonesia is Puncak Jaya (4884 m) and the lowest point is Indian Ocean (0 m). So there are huge differences in altitudes in this country and the weather is very different in them therefore. Keep in mind, that the temperature usually decreases by 1.2 - 1.9 ℃ (2.2 - 3.5 ℉) per 200 m (656 ft), depending on the other conditions. (And we should add, that in the very special condition named thermal inversion even the temperature may be higher in higher altitudes.)
Typical (usual) weather in Kalimantan in January is this: The average highest temperature in Kalimantan in January is 32.8 ℃ (91.04 ℉). The average lowest temperature is 23.3 ℃ (73.94 ℉). At the beginning of January you can expect higher temperatures, the average highest temperature is around 32.85 ℃ (91.13 ℉). At the end of January you can expect lower temperatures, the average highest temperature is around 32.7 ℃ (90.86 ℉). The average number of rainy days in January is 15.1. The average rainfall is 260 mm (look here, what this number means). When planning your travel, please, keep in mind, that actual weather may differ from these average values. The length of the day at the beginning of this month is approximately 12:07 (hours and minutes), in the middle of the month 12:07 and at the end of the month 12:07.These numbers above are valid primarily for the capital and the area around it. It is important to say, that the weather may differ significantly in different altitudes, especially in mountains.Typical (usual) weather in Kalimantan in February is this: The average highest temperature in Kalimantan in February is 32.6 ℃ (90.68 ℉). The average lowest temperature is 23 ℃ (73.4 ℉). At the beginning of February you can expect higher temperatures, the average highest temperature is around 32.7 ℃ (90.86 ℉). At the end of February you can expect higher temperatures, the average highest temperature is around 32.85 ℃ (91.13 ℉). The average number of rainy days in February is 13. The average rainfall is 212 mm (look here, what this number means). When planning your travel, please, keep in mind, that actual weather may differ from these average values. The length of the day at the beginning of this month is approximately 12:07 (hours and minutes), in the middle of the month 12:06 and at the end of the month 12:06.These numbers above are valid primarily for the capital and the area around it. It is important to say, that the weather may differ significantly in different altitudes, especially in mountains.Typical (usual) weather in Kalimantan in March is this: The average highest temperature in Kalimantan in March is 33.1 ℃ (91.58 ℉). The average lowest temperature is 23.6 ℃ (74.48 ℉). At the beginning of March you can expect lower temperatures, the average highest temperature is around 32.85 ℃ (91.13 ℉). At the end of March you can expect higher temperatures, the average highest temperature is around 33.45 ℃ (92.21 ℉). The average number of rainy days in March is 20.8. The average rainfall is 254.6 mm (look here, what this number means). When planning your travel, please, keep in mind, that actual weather may differ from these average values. The length of the day at the beginning of this month is approximately 12:06 (hours and minutes), in the middle of the month 12:06 and at the end of the month 12:06.These numbers above are valid primarily for the capital and the area around it. It is important to say, that the weather may differ significantly in different altitudes, especially in mountains.Typical (usual) weather in Kalimantan in April is this: The average highest temperature in Kalimantan in April is 33.8 ℃ (92.84 ℉). The average lowest temperature is 23.9 ℃ (75.02 ℉). At the beginning of April you can expect lower temperatures, the average highest temperature is around 33.45 ℃ (92.21 ℉). At the end of April you can expect lower temperatures, the average highest temperature is around 33.5 ℃ (92.3 ℉). The average number of rainy days in April is 21.7. The average rainfall is 287.6 mm (look here, what this number means). When planning your travel, please, keep in mind, that actual weather may differ from these average values. The length of the day at the beginning of this month is approximately 12:06 (hours and minutes), in the middle of the month 12:06 and at the end of the month 12:06.These numbers above are valid primarily for the capital and the area around it. It is important to say, that the weather may differ significantly in different altitudes, especially in mountains.Typical (usual) weather in Kalimantan in May is this: The average highest temperature in Kalimantan in May is 33.2 ℃ (91.76 ℉). The average lowest temperature is 23.3 ℃ (73.94 ℉). At the beginning of May you can expect higher temperatures, the average highest temperature is around 33.5 ℃ (92.3 ℉). At the end of May you can expect higher temperatures, the average highest temperature is around 33.6 ℃ (92.48 ℉). The average number of rainy days in May is 20.1. The average rainfall is 254.8 mm (look here, what this number means). When planning your travel, please, keep in mind, that actual weather may differ from these average values. The length of the day at the beginning of this month is approximately 12:06 (hours and minutes), in the middle of the month 12:06 and at the end of the month 12:07.These numbers above are valid primarily for the capital and the area around it. It is important to say, that the weather may differ significantly in different altitudes, especially in mountains.Typical (usual) weather in Kalimantan in June is this: The average highest temperature in Kalimantan in June is 34 ℃ (93.2 ℉). The average lowest temperature is 22.9 ℃ (73.22 ℉). At the beginning of June you can expect lower temperatures, the average highest temperature is around 33.6 ℃ (92.48 ℉). At the end of June you can expect lower temperatures, the average highest temperature is around 33.25 ℃ (91.85 ℉). The average number of rainy days in June is 18.1. The average rainfall is 216.8 mm (look here, what this number means). When planning your travel, please, keep in mind, that actual weather may differ from these average values. The length of the day at the beginning of this month is approximately 12:07 (hours and minutes), in the middle of the month 12:07 and at the end of the month 12:07.These numbers above are valid primarily for the capital and the area around it. It is important to say, that the weather may differ significantly in different altitudes, especially in mountains.Typical (usual) weather in Kalimantan in July is this: The average highest temperature in Kalimantan in July is 32.5 ℃ (90.5 ℉). The average lowest temperature is 22.5 ℃ (72.5 ℉). At the beginning of July you can expect higher temperatures, the average highest temperature is around 33.25 ℃ (91.85 ℉). At the end of July you can expect higher temperatures, the average highest temperature is around 32.95 ℃ (91.31 ℉). The average number of rainy days in July is 15.8. The average rainfall is 198.7 mm (look here, what this number means). When planning your travel, please, keep in mind, that actual weather may differ from these average values. The length of the day at the beginning of this month is approximately 12:07 (hours and minutes), in the middle of the month 12:07 and at the end of the month 12:06.These numbers above are valid primarily for the capital and the area around it. It is important to say, that the weather may differ significantly in different altitudes, especially in mountains.Typical (usual) weather in Kalimantan in August is this: The average highest temperature in Kalimantan in August is 33.4 ℃ (92.12 ℉). The average lowest temperature is 22.5 ℃ (72.5 ℉). At the beginning of August you can expect lower temperatures, the average highest temperature is around 32.95 ℃ (91.31 ℉). At the end of August you can expect lower temperatures, the average highest temperature is around 32.85 ℃ (91.13 ℉). The average number of rainy days in August is 24.5. The average rainfall is 176.9 mm (look here, what this number means). When planning your travel, please, keep in mind, that actual weather may differ from these average values. The length of the day at the beginning of this month is approximately 12:06 (hours and minutes), in the middle of the month 12:06 and at the end of the month 12:06.These numbers above are valid primarily for the capital and the area around it. It is important to say, that the weather may differ significantly in different altitudes, especially in mountains.Typical (usual) weather in Kalimantan in September is this: The average highest temperature in Kalimantan in September is 32.3 ℃ (90.14 ℉). The average lowest temperature is 23 ℃ (73.4 ℉). At the beginning of September you can expect higher temperatures, the average highest temperature is around 32.85 ℃ (91.13 ℉). At the end of September you can expect lower temperatures, the average highest temperature is around 32.15 ℃ (89.87 ℉). The average number of rainy days in September is 13.7. The average rainfall is 288.7 mm (look here, what this number means). When planning your travel, please, keep in mind, that actual weather may differ from these average values. The length of the day at the beginning of this month is approximately 12:06 (hours and minutes), in the middle of the month 12:06 and at the end of the month 12:06.These numbers above are valid primarily for the capital and the area around it. It is important to say, that the weather may differ significantly in different altitudes, especially in mountains.Typical (usual) weather in Kalimantan in October is this: The average highest temperature in Kalimantan in October is 32 ℃ (89.6 ℉). The average lowest temperature is 22.8 ℃ (73.04 ℉). At the beginning of October you can expect higher temperatures, the average highest temperature is around 32.15 ℃ (89.87 ℉). At the end of October you can expect lower temperatures, the average highest temperature is around 32 ℃ (89.6 ℉). The average number of rainy days in October is 27.5. The average rainfall is 335.9 mm (look here, what this number means). When planning your travel, please, keep in mind, that actual weather may differ from these average values. The length of the day at the beginning of this month is approximately 12:06 (hours and minutes), in the middle of the month 12:06 and at the end of the month 12:06.These numbers above are valid primarily for the capital and the area around it. It is important to say, that the weather may differ significantly in different altitudes, especially in mountains.Typical (usual) weather in Kalimantan in November is this: The average highest temperature in Kalimantan in November is 32 ℃ (89.6 ℉). The average lowest temperature is 22.9 ℃ (73.22 ℉). At the beginning of November you can expect lower temperatures, the average highest temperature is around 32 ℃ (89.6 ℉). At the end of November you can expect higher temperatures, the average highest temperature is around 32.45 ℃ (90.41 ℉). The average number of rainy days in November is 24.4. The average rainfall is 393.8 mm (look here, what this number means). When planning your travel, please, keep in mind, that actual weather may differ from these average values. The length of the day at the beginning of this month is approximately 12:06 (hours and minutes), in the middle of the month 12:07 and at the end of the month 12:07.These numbers above are valid primarily for the capital and the area around it. It is important to say, that the weather may differ significantly in different altitudes, especially in mountains.Typical (usual) weather in Kalimantan in December is this: The average highest temperature in Kalimantan in December is 32.9 ℃ (91.22 ℉). The average lowest temperature is 22.3 ℃ (72.14 ℉). At the beginning of December you can expect lower temperatures, the average highest temperature is around 32.45 ℃ (90.41 ℉). At the end of December you can expect lower temperatures, the average highest temperature is around 32.85 ℃ (91.13 ℉). The average number of rainy days in December is 22.4. The average rainfall is 299.6 mm (look here, what this number means). When planning your travel, please, keep in mind, that actual weather may differ from these average values. The length of the day at the beginning of this month is approximately 12:07 (hours and minutes), in the middle of the month 12:07 and at the end of the month 12:07.These numbers above are valid primarily for the capital and the area around it. It is important to say, that the weather may differ significantly in different altitudes, especially in mountains.