Fall in Bangkok always keeps you guessing. You’ll get a mix of heavy rains, warm temperatures, and skies that seem to change their mind by the hour. Daytime highs hover near 90°F (32°C), humidity peaks, and September usually drenches the city the most.
As November approaches, the rain finally lets up, the sky clears, and it feels a lot more comfortable to wander around.
You can really feel the shift in the air. September brings muggy, damp days, October starts to feel more balanced, and by November, Bangkok slides into its drier season.
Sunshine hours tick up, so outdoor plans don’t get rained out as often, even though the heat doesn’t really go anywhere.
These changes shape your day-to-day in Bangkok, from deciding how long you’ll stay outside to whether you’ll risk a boat ride or a day trip beyond the city.
Knowing the patterns helps you enjoy Bangkok’s fall weather without getting caught in a surprise downpour or sweating through a sticky afternoon.
Overview of Fall Weather in Bangkok
In Bangkok’s fall, you deal with high humidity, frequent rain, and warm temperatures that don’t budge much. The city’s spot near the Gulf of Thailand really sets the tone, keeping things both wet and hot.
Typical Fall Climate Patterns
From September to November, Bangkok stays hot. Daily highs stick around 90°F (32°C). Nights don’t cool off much, usually landing near 82°F (28°C), so don’t expect much relief after dark.
September pours down the most rain, often over 330 mm (13 in). October calms a bit but still brings plenty of showers. By November, it finally dries out, with rain totals dropping to about 50 mm (2 in).
Humidity lingers between 75–79%, making the heat feel even more intense. Still, you’ll see 5–8 hours of sunshine per day, especially as fall winds down.
Outdoor activities in September might feel rough with all the heat, humidity, and rain. By November, things open up and sightseeing gets a lot easier.
Bangkok’s Location and Its Impact on Weather
Bangkok sits right in central Thailand, close to the Gulf of Thailand. This location lets in moist air that fuels the long rainy season and keeps humidity up.
The city’s flat terrain means rainwater doesn’t drain fast. Flooding pops up quickly during the peak rainfall months, especially in September and October.
Because Bangkok sits in a tropical savanna climate zone, temperatures barely budge all year. You won’t see big seasonal swings like in temperate places. The real shift comes when monsoon rains fade and drier weather takes over as fall moves along.
You end up with a mix of steady heat, high humidity, and that classic seasonal rain that defines fall in Bangkok.
Temperature Trends During Fall
You’ll notice a slow drop in daily highs and lows as fall goes on, and the rain and clouds back off too. It’s still warm, but evenings start to feel a bit nicer and the skies clear up compared to the soggy start of the season.
Average High and Low Temperatures
Highs in fall stay close to 90°F (32°C). They rarely dip below 84°F (29°C) or jump above 94°F (34°C), so afternoons are always warm.
At night, it cools off a bit more. Lows fall from about 79°F (26°C) in September to 74°F (23°C) by late November. Every once in a while, nights drop near 69°F (21°C), which feels pretty refreshing for Bangkok.
If you want to compare, April is the real scorcher with highs near 95°F (35°C), while December chills out a bit with highs around 88°F (31°C). Fall lands somewhere in the middle—not as blazing as April, not as cool as December.
Hourly Temperature Variations
Bangkok’s temperatures don’t swing much between day and night. In fall, early mornings usually start in the mid-70s °F, and afternoons climb into the upper 80s or low 90s °F.
The hottest stretch hits between 1 PM and 4 PM. Even after sunset, it stays warm, with evenings often hanging in the upper 70s °F.
High humidity keeps nights from cooling off much. September nights can still feel muggy, but by November, the air dries out a bit, making evenings outside more pleasant.
Comparison to Other Seasons
If you compare fall to the rest of the year, you’ll see the difference. In April, the heat and humidity really ramp up. December cools down and dries out, making it a favorite for many.
Fall starts with September’s heavy rains, but the temperature stays steady. As you move into October and November, the rain eases, skies brighten, and nights get a touch cooler.
This transition makes fall its own thing. You get those warm Bangkok days, but without April’s extremes or December’s mildness.
Rainfall and Humidity Patterns
Bangkok’s fall brings some of the year’s heaviest rains, then slowly shifts to a drier, cooler stretch. Humidity stays high at first, but by December, it drops, making it a lot nicer for outdoor plans.
Monthly Rainfall Distribution
September stands as the wettest month in Bangkok, dumping around 330 mm (13 in) of rain. Downpours come fast and hard, flooding streets in no time. If you’re visiting, plan for delays.
October still gets a good amount of rain—about 200 mm (8 in)—but showers don’t last as long. It’s easier to get around, though you’ll still want an umbrella handy.
By November, rainfall drops sharply to about 50 mm (2 in). Storms become rare and the sky clears up. December barely sees any rain at all, just 6–10 mm (0.25–0.4 in) on average, so you get a lot of dry days to explore.
Humidity Levels Throughout Fall
Humidity stays high in early fall, often hitting 78–79% in September. The air feels heavy, and outdoor activities can wear you out fast. Early mornings or evenings are your best bet for sightseeing.
In October, humidity drops a bit to around 75–76%. It’s still muggy, but you’ll notice more sun between showers.
By November, humidity falls to about 70%, and by December, it can go down to 66%. The air finally feels more comfortable, and exploring the city gets easier.
Transition from Wet to Dry Season
From September through December, Bangkok transitions from wet to dry. September and October bring heavy rainfall and sticky air.
November signals the start of the dry season. Rainfall drops fast, the sky brightens, and humidity dips. Outdoor tours and river activities get a lot more reliable.
Cloud Cover and Sunshine
Fall skies in Bangkok shift from thick clouds to much clearer blue as the season wraps up. This change means you’ll see more sunlight and brighter afternoons as the rain backs off.
Changes in Cloudiness
Early fall brings mostly overcast or cloudy skies. In September, cloud cover hangs around about 90% of the time, making things feel pretty dreary.
Cloudiness drops quickly as the weeks go by. By late November, clouds cover the sky just 58% of the time, so you get a better shot at clear days.
The clearest weather usually shows up near the end of November, with a 42% chance of a clear or mostly clear day. That lines up with the end of the rainy season.
So, if you’re planning, expect September to be cloudy and humid, while November gives you brighter, friendlier skies.
Average Daily Sunshine Hours
Sunshine in Bangkok during fall depends on clouds and how long the days are. In early September, daylight lasts about 12 hours and 23 minutes, but by late November, it shrinks to 11 hours and 23 minutes.
Even though days get a bit shorter, less cloud cover means more usable sunshine hours. September feels dim with all the storms, but November brings those bright afternoons and longer sunny spells.
On average, you get around 5 to 6 hours of direct sunshine per day. November’s the best for reliable sun, with less rain and clearer skies.
Late fall really is one of the best times to enjoy outdoor activities in Bangkok.
Sea Temperature and Water Activities
Bangkok’s nearby waters stay warm year-round, barely changing with the seasons. Swimming is always an option, but heavy rain and humidity in early fall might keep you on dry land more often than you’d like.
Average Sea Temperature in Fall
In fall, the average sea temperature near Bangkok sits around 85°F (29°C) in September and drops just a bit to 83°F (28°C) in November. The water cools slightly, which can actually feel nice after a hot day.
September’s sea temperature matches what you’d find in April, the hottest month. By November, it cools a little but still feels great for swimming.
The Gulf of Thailand is pretty shallow near Bangkok, so it holds heat longer than deeper seas. You rarely get a shock of cold water, even as the air cools off.
For most people, the sea feels more like a warm bath than a cool escape. If you like your swims on the cooler side, late November is probably your sweet spot.
Best Months for Swimming
You can swim in Bangkok’s waters all year, but October and November usually offer the best conditions in fall. Rain lets up after September, and the sky clears, so you get more good beach days.
September’s heavy rain and high humidity can limit your swim time, even though the water’s warm. By November, the weather is steadier, storms are rare, and the sea is calmer.
In December, things keep improving, though the water cools a bit more. Many travelers love this combo of warm water and dry air for longer stays by the coast.
For the best experience, plan your water activities like swimming or snorkeling for late fall, when the sea stays warm and the weather finally settles down.
Daylight Hours and Seasonal Changes
Bangkok doesn’t see big swings in daylight like places farther from the equator. The days stay pretty steady, but you’ll notice a small shift in daylight hours and when the sun rises and sets.
Length of Daylight During Fall
During fall, Bangkok gets about 11.8 to 12 hours of daylight per day. The change from September to November is small, but you might spot it if you’re paying attention.
In September, daylight averages around 12 hours and 10 minutes. By November, it slips to about 11 hours and 30 minutes. This slow shift goes hand in hand with the move from rainy to drier months.
Since the difference isn’t huge, you won’t deal with those long, dark evenings that happen in higher latitudes. The steady daylight makes it easy to plan your days without worrying about sudden changes.
This consistency is great if you’re scheduling outdoor sightseeing—your window of daylight stays pretty much the same during fall.
Sunrise and Sunset Times
Sunrise and sunset in Bangkok change gradually during fall. In September, the sun comes up around 6:05 AM and goes down close to 6:15 PM.
By November, you’ll notice sunrise happens later, near 6:20 AM. Sunset arrives earlier too, at about 5:45 PM.
Evenings feel a bit shorter as the season moves on. Dusk creeps in a little earlier in November than it does in September, although honestly, it’s not a huge shift.
Here’s a quick breakdown:
| Month | Sunrise (approx.) | Sunset (approx.) |
|---|---|---|
| September | 6:05 AM | 6:15 PM |
| October | 6:10 AM | 6:00 PM |
| November | 6:20 AM | 5:45 PM |
These times can help you figure out when to start a day trip or plan an evening out. If you like cooler weather, those early mornings are usually the nicest time to get outside.