Do you need to know, when is the best time to go to Papua? Then you should take a look here, what weather you can expect there during the year.
Papua 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: Asmat, Baliem Valley, Biak, Jayapura, Lorentz National Park, Raja Ampat, Sorong.
Let's look now what weather you can expect in the area around Biak and in many other cities. The warmest month here is March, the average maximum temperature is 32 ℃ (89.6 ℉). The average minimum temperature in this month is 24.1 ℃ (75.38 ℉). The coldest month here is February, the average maximum temperature is 28.9 ℃ (84.02 ℉). The average minimum temperature in this month is 24.2 ℃ (75.56 ℉). The most rainy month here is January, the average number of rainy days is 25.5. The least rainy month here is November, the average number of rainy days is 12.1. 
When travelling around Papua, 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 Papua in January is this: The average highest temperature in Papua in January is 29.6 ℃ (85.28 ℉). The average lowest temperature is 24.2 ℃ (75.56 ℉). At the beginning of January you can expect higher temperatures, the average highest temperature is around 29.9 ℃ (85.82 ℉). At the end of January you can expect lower temperatures, the average highest temperature is around 29.25 ℃ (84.65 ℉). The average number of rainy days in January is 25.5. The average rainfall is 274.3 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 12:11 (hours and minutes), in the middle of the month 12:10 and at the end of the month 12:09.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 Papua in February is this: The average highest temperature in Papua in February is 28.9 ℃ (84.02 ℉). The average lowest temperature is 24.2 ℃ (75.56 ℉). At the beginning of February you can expect higher temperatures, the average highest temperature is around 29.25 ℃ (84.65 ℉). At the end of February you can expect higher temperatures, the average highest temperature is around 30.45 ℃ (86.81 ℉). The average number of rainy days in February is 22.4. The average rainfall is 245.3 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 12:09 (hours and minutes), in the middle of the month 12:08 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 Papua in March is this: The average highest temperature in Papua in March is 32 ℃ (89.6 ℉). The average lowest temperature is 24.1 ℃ (75.38 ℉). At the beginning of March you can expect lower temperatures, the average highest temperature is around 30.45 ℃ (86.81 ℉). At the end of March you can expect lower temperatures, the average highest temperature is around 31.45 ℃ (88.61 ℉). The average number of rainy days in March is 19.8. The average rainfall is 272.9 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 12:07 (hours and minutes), in the middle of the month 12:06 and at the end of the month 12:05.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 Papua in April is this: The average highest temperature in Papua in April is 30.9 ℃ (87.62 ℉). The average lowest temperature is 23.9 ℃ (75.02 ℉). At the beginning of April you can expect higher temperatures, the average highest temperature is around 31.45 ℃ (88.61 ℉). At the end of April you can expect lower temperatures, the average highest temperature is around 30.45 ℃ (86.81 ℉). The average number of rainy days in April is 17.6. The average rainfall is 209.1 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 12:05 (hours and minutes), in the middle of the month 12:05 and at the end of the month 12:04.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 Papua in May is this: The average highest temperature in Papua in May is 30 ℃ (86 ℉). The average lowest temperature is 23.6 ℃ (74.48 ℉). At the beginning of May you can expect higher temperatures, the average highest temperature is around 30.45 ℃ (86.81 ℉). At the end of May you can expect lower temperatures, the average highest temperature is around 29.75 ℃ (85.55 ℉). The average number of rainy days in May is 21.5. The average rainfall is 266.1 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 12:04 (hours and minutes), in the middle of the month 12:03 and at the end of the month 12:03.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 Papua in June is this: The average highest temperature in Papua in June is 29.5 ℃ (85.1 ℉). The average lowest temperature is 23.2 ℃ (73.76 ℉). At the beginning of June you can expect higher temperatures, the average highest temperature is around 29.75 ℃ (85.55 ℉). At the end of June you can expect higher temperatures, the average highest temperature is around 30.65 ℃ (87.17 ℉). The average number of rainy days in June is 15.7. The average rainfall is 219.3 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 12:03 (hours and minutes), in the middle of the month 12:03 and at the end of the month 12:03.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 Papua in July is this: The average highest temperature in Papua in July is 31.8 ℃ (89.24 ℉). The average lowest temperature is 23.8 ℃ (74.84 ℉). At the beginning of July you can expect lower temperatures, the average highest temperature is around 30.65 ℃ (87.17 ℉). At the end of July you can expect lower temperatures, the average highest temperature is around 30.9 ℃ (87.62 ℉). The average number of rainy days in July is 14.2. The average rainfall is 232 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 12:03 (hours and minutes), in the middle of the month 12:03 and at the end of the month 12:03.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 Papua in August is this: The average highest temperature in Papua in August is 30 ℃ (86 ℉). The average lowest temperature is 22.9 ℃ (73.22 ℉). At the beginning of August you can expect higher temperatures, the average highest temperature is around 30.9 ℃ (87.62 ℉). At the end of August you can expect lower temperatures, the average highest temperature is around 29.6 ℃ (85.28 ℉). The average number of rainy days in August is 19.4. The average rainfall is 247.7 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 12:03 (hours and minutes), in the middle of the month 12:04 and at the end of the month 12:05.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 Papua in September is this: The average highest temperature in Papua in September is 29.2 ℃ (84.56 ℉). The average lowest temperature is 23 ℃ (73.4 ℉). At the beginning of September you can expect higher temperatures, the average highest temperature is around 29.6 ℃ (85.28 ℉). At the end of September you can expect higher temperatures, the average highest temperature is around 29.7 ℃ (85.46 ℉). The average number of rainy days in September is 19.9. The average rainfall is 205.8 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 12:05 (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 Papua in October is this: The average highest temperature in Papua in October is 30.2 ℃ (86.36 ℉). The average lowest temperature is 23.7 ℃ (74.66 ℉). At the beginning of October you can expect lower temperatures, the average highest temperature is around 29.7 ℃ (85.46 ℉). At the end of October you can expect higher temperatures, the average highest temperature is around 30.5 ℃ (86.9 ℉). The average number of rainy days in October is 17.3. The average rainfall is 203.5 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 12:08.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 Papua in November is this: The average highest temperature in Papua in November is 30.8 ℃ (87.44 ℉). The average lowest temperature is 23.4 ℃ (74.12 ℉). At the beginning of November you can expect lower temperatures, the average highest temperature is around 30.5 ℃ (86.9 ℉). At the end of November you can expect lower temperatures, the average highest temperature is around 30.5 ℃ (86.9 ℉). The average number of rainy days in November is 12.1. The average rainfall is 196.8 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 12:08 (hours and minutes), in the middle of the month 12:09 and at the end of the month 12:10.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 Papua in December is this: The average highest temperature in Papua in December is 30.2 ℃ (86.36 ℉). The average lowest temperature is 23.9 ℃ (75.02 ℉). At the beginning of December you can expect higher temperatures, the average highest temperature is around 30.5 ℃ (86.9 ℉). At the end of December you can expect lower temperatures, the average highest temperature is around 29.9 ℃ (85.82 ℉). The average number of rainy days in December is 15.3. The average rainfall is 239.5 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 12:10 (hours and minutes), in the middle of the month 12:11 and at the end of the month 12:11.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.