Pematangsiantar climate
Pematangsiantar (Indonesia) has a tropical rainforest climate (Köppen Af). The average temperature over the year is 24 °C76 °F, and about 2,724 mm107 in of precipitation falls in an average year.
Temperature by month
Precipitation by month
Pematangsiantar climate table
| Month | High °C°F | Low °C°F | Mean °C°F | Precip. mmin |
|---|---|---|---|---|
| Jan | 2679 | 2170 | 2475 | 1807.1 |
| Feb | 2781 | 2171 | 2476 | 1375.4 |
| Mar | 2781 | 2271 | 2576 | 1887.4 |
| Apr | 2781 | 2272 | 2577 | 1787.0 |
| May | 2781 | 2373 | 2577 | 2258.9 |
| Jun | 2781 | 2272 | 2577 | 1566.1 |
| Jul | 2781 | 2271 | 2576 | 1997.8 |
| Aug | 2781 | 2271 | 2576 | 2369.3 |
| Sep | 2780 | 2271 | 2476 | 29812 |
| Oct | 2680 | 2271 | 2475 | 35414 |
| Nov | 2679 | 2271 | 2475 | 29312 |
| Dec | 2679 | 2171 | 2475 | 28011 |
| Year | 2781 | 2170 | 2476 | 2,724107 |
“Year” row: highest monthly high, lowest monthly low, annual mean and annual total.
| Month | Humid. | Cloud | Solar | Daylight |
|---|---|---|---|---|
| Jan | 87% | 88% | 4.5 | 11:58 |
| Feb | 85% | 81% | 4.9 | 12:01 |
| Mar | 85% | 82% | 5.2 | 12:06 |
| Apr | 86% | 88% | 5.0 | 12:11 |
| May | 86% | 88% | 4.9 | 12:15 |
| Jun | 85% | 84% | 4.9 | 12:17 |
| Jul | 84% | 85% | 4.9 | 12:17 |
| Aug | 85% | 88% | 4.9 | 12:13 |
| Sep | 86% | 91% | 4.8 | 12:08 |
| Oct | 87% | 94% | 4.5 | 12:03 |
| Nov | 89% | 94% | 4.4 | 11:59 |
| Dec | 89% | 92% | 4.3 | 11:57 |
Humid. = average relative humidity at 2 m; cloud = average cloud amount; solar = average daily solar energy reaching the ground in kWh/m² (all-sky); daylight in hours:minutes, calculated for the 15th of each month.
What the climate of Pematangsiantar is like
The warmest month is May, with an average high of 27 °C81 °F and a low of 23 °C73 °F. The coldest is December, when highs average 26 °C79 °F and lows 21 °C71 °F. Temperatures barely change through the year: the warmest and the coolest month differ by only 1.4 °C2.5 °F.
It is very wet, receiving about 2,724 mm107 in of precipitation per year. The wettest three-month stretch is September–November, which brings 35% of the annual total. The wettest month is October (354 mm14 in), the driest is February (137 mm5.4 in).
Relative humidity ranges from 84% in July to 89% in November. The clearest skies (lowest average cloud amount, 81%) are typical of February. Average wind speed near the ground ranges from 3 km/h (2 mph) in June to 4 km/h (2 mph) in January.
Best time to visit Pematangsiantar
Based on these averages, the most comfortable months for sightseeing and outdoor activities are February: average highs of 27 °C81 °F to 27 °C81 °F with 137 mm5.4 in to 137 mm5.4 in of precipitation per month.
The most challenging month is October, which is very wet (354 mm14 in) and humid (87% relative humidity).
Comfort score: months are ranked by how close they come to an average high of 21–28 °C (70–82 °F), lows above 5 °C (41 °F), little precipitation and moderate humidity. The best-ranked months of each place are recommended, even where none meets all of these. These are general rules of thumb applied to long-term averages.
What to pack for Pematangsiantar
- Wetter months (August–December) — highs 2679 to 27 °C81 °F, lows 2171 to 22 °C71 °F, about 292 mm12 in of precipitation a month. Pack light summer clothes such as T-shirts, shorts or light dresses and a good rain jacket or umbrella and quick-drying shoes.
- Drier months (January–July) — highs 2679 to 27 °C81 °F, lows 2170 to 23 °C73 °F, about 180 mm7.1 in of precipitation a month. Pack light summer clothes such as T-shirts, shorts or light dresses and an umbrella or light rain jacket.
How Pematangsiantar compares
Compared with Medan, about 82 km to the northwest, Pematangsiantar is on average 2.4 °C4.2 °F cooler and receives 20% more precipitation (2,724 mm107 in vs 2,276 mm90 in). The difference is largest in May (2.5 °C4.4 °F cooler).
Of the 110 places in Indonesia covered by World Climates, Pematangsiantar is the 100th warmest by annual mean temperature and the 20th wettest by annual precipitation. See all of them on the Indonesia climate page.
Places in other countries with the most similar temperature and rainfall pattern: Manolo Fortich (Philippines, Af), Silang (Philippines, Af) and Quezon (Philippines, Af).
The same NASA POWER grid cell also contains Kisaran (pop. 141,915). Their long-term averages in this dataset are essentially the same as for Pematangsiantar, so they do not have separate pages.
Nearby places
- Tebingtinggi 42 km · 28 °C82 °F · 2,334 mm92 in
- Tanjungbalai 81 km · 27 °C81 °F · 2,627 mm103 in
- Medan 82 km · 27 °C80 °F · 2,276 mm90 in
- Belawan 100 km · 28 °C82 °F · 2,477 mm98 in
- Rantauprapat 128 km · 26 °C79 °F · 3,879 mm153 in
- Subulussalam 136 km · 27 °C80 °F · 3,173 mm125 in
- Padangsidempuan 177 km · 25 °C77 °F · 4,346 mm171 in
- Langsa 207 km · 28 °C82 °F · 2,347 mm92 in
Frequently asked questions
What is the warmest month in Pematangsiantar?
May is the warmest month in Pematangsiantar, with an average high of 27 °C (81 °F) and an average low of 23 °C (73 °F).
What is the coldest month in Pematangsiantar?
December is the coldest month, with an average high of 26 °C (79 °F) and an average low of 21 °C (71 °F).
When does it rain the most in Pematangsiantar?
October is the wettest month with about 354 mm (14.0 in) of precipitation; February is the driest with about 137 mm (5.4 in).
What is the best time to visit Pematangsiantar?
Judging by long-term averages, the most comfortable months are February.
About this data
All figures are 25-year averages (January 2001 – December 2025) from the NASA POWER project. Temperature, humidity, wind and precipitation come from the MERRA-2 reanalysis (precipitation is the bias-corrected MERRA-2 product), cloud and solar values from CERES satellite data. They describe a grid cell of roughly 50–70 km, not a single weather station, so they can differ from airport records — most of all on coasts, in mountains and for rainfall. Average highs and lows are the monthly mean temperature plus/minus half of the average daily temperature range. Counts of rainy days are not part of this dataset.
The grid cell’s average elevation is 162 m, while Pematangsiantar lies at about 388 m. Temperatures on this page were therefore adjusted by −1.5 °C2.6 °F using the standard lapse rate of 6.5 °C per 1,000 m.