Si Racha climate
Si Racha (Thailand) has a tropical savanna (dry winter) climate (Köppen Aw). The average temperature over the year is 28 °C83 °F, and about 1,347 mm53 in of precipitation falls in an average year.
Temperature by month
Precipitation by month
Si Racha climate table
| Month | High °C°F | Low °C°F | Mean °C°F | Precip. mmin |
|---|---|---|---|---|
| Jan | 2983 | 2576 | 2780 | 261.0 |
| Feb | 2984 | 2678 | 2781 | 180.7 |
| Mar | 3085 | 2781 | 2883 | 562.2 |
| Apr | 3087 | 2883 | 2985 | 722.8 |
| May | 3087 | 2984 | 3085 | 1526.0 |
| Jun | 3086 | 2882 | 2984 | 1596.3 |
| Jul | 2985 | 2882 | 2883 | 1606.3 |
| Aug | 2985 | 2781 | 2883 | 1495.9 |
| Sep | 2984 | 2781 | 2883 | 2399.4 |
| Oct | 2984 | 2781 | 2882 | 2379.3 |
| Nov | 2984 | 2679 | 2882 | 642.5 |
| Dec | 2983 | 2476 | 2680 | 140.6 |
| Year | 3087 | 2476 | 2883 | 1,34753 |
“Year” row: highest monthly high, lowest monthly low, annual mean and annual total.
| Month | Humid. | Cloud | Solar | Daylight |
|---|---|---|---|---|
| Jan | 72% | 40% | 5.0 | 11:26 |
| Feb | 75% | 35% | 5.5 | 11:42 |
| Mar | 77% | 48% | 5.7 | 12:02 |
| Apr | 76% | 61% | 6.1 | 12:25 |
| May | 78% | 84% | 5.5 | 12:44 |
| Jun | 79% | 89% | 5.3 | 12:54 |
| Jul | 79% | 91% | 5.1 | 12:50 |
| Aug | 79% | 92% | 5.1 | 12:33 |
| Sep | 81% | 91% | 4.9 | 12:11 |
| Oct | 80% | 78% | 4.7 | 11:49 |
| Nov | 77% | 59% | 4.9 | 11:30 |
| Dec | 73% | 47% | 4.9 | 11:21 |
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 Si Racha is like
The warmest month is May, with an average high of 30 °C87 °F and a low of 29 °C84 °F. The coldest is December, when highs average 29 °C83 °F and lows 24 °C76 °F. Seasonal differences are small — just 3.1 °C5.5 °F between the warmest and the coolest month.
It is wet, with about 1,347 mm53 in of precipitation per year. The wettest three-month stretch is August–October, which brings 46% of the annual total. Months with less than 20 mm0.8 in on average: February and December. The wettest month is September (239 mm9.4 in), the driest is December (14 mm0.6 in).
Relative humidity ranges from 72% in January to 81% in September. The clearest skies (lowest average cloud amount, 35%) are typical of February. Average wind speed near the ground ranges from 11 km/h (7 mph) in October to 15 km/h (10 mph) in July. Daylight lasts from about 11.4 hours in December to 12.9 hours in June.
Best time to visit Si Racha
Based on these averages, the most comfortable months for sightseeing and outdoor activities are November–March: average highs of 29 °C83 °F to 30 °C85 °F with 14 mm0.6 in to 64 mm2.5 in of precipitation per month.
The most challenging month is September, which is very wet (239 mm9.4 in) and humid (81% 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 Si Racha
- Wetter months (May–October) — highs 2984 to 30 °C87 °F, lows 2781 to 29 °C84 °F, about 183 mm7.2 in of precipitation a month. Pack light summer clothes such as T-shirts, shorts or light dresses and an umbrella or light rain jacket.
- Drier months (November–April) — highs 2983 to 30 °C87 °F, lows 2476 to 28 °C83 °F, about 42 mm1.6 in of precipitation a month. Pack light summer clothes such as T-shirts, shorts or light dresses.
How Si Racha compares
Compared with Chon Buri, about 22 km to the north, Si Racha is on average 0.6 °C1.1 °F warmer and receives 11% less precipitation (1,347 mm53 in vs 1,508 mm59 in). The difference is largest in November (1.8 °C3.2 °F warmer).
Of the 22 places in Thailand covered by World Climates, Si Racha is the 2nd warmest by annual mean temperature and the 13th wettest by annual precipitation. See all of them on the Thailand climate page.
Places in other countries with the most similar temperature and rainfall pattern: Myeik (Myanmar, Aw), Rạch Giá (Vietnam, Aw) and Tịnh Biên (Vietnam, Aw).
Nearby places
- Chon Buri 22 km · 27 °C81 °F · 1,508 mm59 in
- Pattaya 27 km · 28 °C83 °F · 1,347 mm53 in
- Samut Prakan 59 km · 28 °C82 °F · 1,302 mm51 in
- Rayong 65 km · 28 °C82 °F · 2,064 mm81 in
- Bangkok 80 km · 28 °C82 °F · 1,361 mm54 in
- Khlong Luang 104 km · 28 °C82 °F · 1,361 mm54 in
- Si Maha Phot 108 km · 27 °C81 °F · 1,546 mm61 in
- Nakhon Pathom 120 km · 28 °C82 °F · 1,195 mm47 in
Frequently asked questions
What is the warmest month in Si Racha?
May is the warmest month in Si Racha, with an average high of 30 °C (87 °F) and an average low of 29 °C (84 °F).
What is the coldest month in Si Racha?
December is the coldest month, with an average high of 29 °C (83 °F) and an average low of 24 °C (76 °F).
When does it rain the most in Si Racha?
September is the wettest month with about 239 mm (9.4 in) of precipitation; December is the driest with about 14 mm (0.6 in).
What is the best time to visit Si Racha?
Judging by long-term averages, the most comfortable months are November–March.
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.