Fall in Chiang Mai feels like a breath of fresh air after the heavy rains of late summer. You’ll notice cooler, more comfortable days take over.
Daytime highs hover around 30°C (86°F) in September and usually drop to about 28°C (82°F) by November. Nights cool off into the upper teens Celsius, or the mid-60s °F.
This shift brings a balance that makes outdoor adventures so much nicer than in the muggy or blazing-hot months.
Rainfall drops off fast as fall moves along. September still brings frequent showers, but by November, rain is rare and the sky clears up a lot.
Humidity eases, too, so the air gets lighter, making it easier to explore both the city and the mountains.
With mild temps, fewer rainy days, and better air quality, fall really does offer one of the best times to check out Chiang Mai. Whether you’re wandering temples in the Old City, hiking Doi Suthep, or joining local festivals, the weather’s on your side.
Overview of Chiang Mai’s Fall Climate
Fall in Chiang Mai brings warm days, cooler nights, and a sharp drop in rainfall. The shift from humid and wet to clearer skies and comfy weather happens pretty quickly.
Seasonal Weather Patterns
During fall, Chiang Mai’s daily highs average about 86°F (30°C). Early on, highs might touch 92°F (33°C), while lows stick near 75°F (24°C).
By late November, nights can dip to about 64°F (18°C), making evenings a lot more comfortable.
Rainfall drops fast. In September, you might still see 7–8 inches (190 mm) of rain, but by November, it’s less than 1 inch (25 mm). Wet days go from more than half the month in September to just a handful by late fall.
Humidity falls, too. Early fall feels muggy most days, but by late November, the air dries out. Outdoor stuff gets easier and a lot more pleasant compared to the rainy season.
Daylight shortens. September gives you over 12 hours of sun, but by November, it’s closer to 11 hours. Sunrise comes later and sunset sneaks in earlier, hinting that the cool season’s on the way.
Transition from Rainy to Cool Season
At the start of fall, you’ll still feel the rainy season—showers and cloudy skies stick around. In early September, there’s nearly a 90% chance of overcast skies, but by late November, you’ll see clear or mostly clear weather more than half the time.
Rainfall and humidity drop week by week. The ground dries, rivers shrink, and the air gets cleaner. By late fall, you’ll find steady weather with sunny days and cool nights.
Wind and air movement change, too. Early fall brings light, variable winds from the south or west. By late November, breezes come more from the east, carrying drier air.
The switch from wet to cool season happens fast. If you visit in September, you’ll want rain gear. By November, you can expect clear skies, maybe a light jacket at night, and warm days.
Average Daytime Temperature in Fall
Chiang Mai’s fall days stay warm but get cooler as you move from September to November. Highs start out close to summer levels, then settle into more comfortable numbers by the end of the season.
Monthly Temperature Trends
In September, expect average daytime temps around 86°F (30°C). Highs can reach 88°F, while lows hover near 75°F. The afternoons still feel humid and warm.
By October, highs drop a bit to 84–86°F (29–30°C). Nights cool off more, often dipping into the mid-60s°F. October tends to feel balanced—warm but not overbearing.
In November, things shift more clearly. Average highs fall to 82–84°F (28–29°C), and lows can get down to 64°F or even a little lower. The air feels drier, and lower humidity makes the heat easier to handle.
| Month | Avg High °F | Avg Low °F | Conditions |
|---|---|---|---|
| September | 86–88 | 74–75 | Warm, humid |
| October | 84–86 | 67–70 | Warm, less humid |
| November | 82–84 | 63–66 | Mild, drier air |
Day and Night Temperature Differences
Fall brings a noticeable gap between day and night temps. In September, the difference is small—just 10–12°F. Humidity keeps the nights warm, so evenings can feel sticky.
By October, the gap gets wider. Daytime highs stick in the mid-80s°F, but nights often fall into the upper 60s°F. Mornings and evenings feel much cooler than the afternoons.
November shows the biggest contrast. Highs reach the low 80s°F, but lows can drop into the mid-60s°F, sometimes even upper 50s°F on rare nights. This cool air at night brings real relief after warm days and makes November perfect for being outside.
Rainy Days and Precipitation Levels
Fall in Chiang Mai means you’ll notice the rains of late summer fading as November approaches. Rain becomes less frequent each month, and total precipitation drops sharply as the wet season wraps up.
Frequency of Rainfall in Fall
In September, expect rain on 15–18 days out of the month. Showers usually pop up in the afternoon or evening, lasting a few hours—not all day. Cloud cover is still common, keeping things humid.
By October, rainy days drop to about 10–12 days. Rain is still possible, but storms get lighter and more scattered. You’ll see longer stretches of sunshine between showers.
November brings a real change. Rain falls on just 2–4 days on average, and many travelers don’t see any at all during their stay. Skies clear up, and outdoor plans rarely get interrupted.
Monthly Precipitation Totals
September still sits in the monsoon season, with totals around 200–230 mm of rain. It’s one of the wetter months, though not as wet as August.
Rainfall in October drops to about 100–120 mm. Afternoon showers can still happen, but they’re shorter and lighter.
By November, precipitation falls sharply to 20–40 mm. This low number signals the start of the cool, dry season. You’ll notice lower humidity and clearer skies, making the weather much more predictable.
The difference between September and November really shows how quickly Chiang Mai dries out in the fall.
Relative Humidity During Fall Months
As fall rolls in, Chiang Mai’s humidity drops off as the rains fade and cooler, drier air settles in. September stays sticky, but by November, you’ll feel the difference.
Monthly Humidity Averages
September brings relative humidity of 80–85%, which makes it one of the stickiest months. The rainy season lingers, with plenty of clouds and showers.
In October, humidity falls to about 70–75%. With less rain and more sun, the air feels less damp, though you’ll still get some muggy days.
By November, humidity drops to 60–65%. That’s when the cool, dry season arrives. The lower humidity makes the air fresher, and mornings can even feel crisp.
| Month | Average Relative Humidity |
|---|---|
| September | 80–85% |
| October | 70–75% |
| November | 60–65% |
You can really see the steady drop in humidity as fall moves along.
Impact of Humidity on Comfort
High humidity in September makes daytime temps feel hotter than they are. Even if the thermometer looks reasonable, sweat doesn’t evaporate as fast, so you can feel sticky and uncomfortable outside.
The drop in humidity by October means you’ll feel better out and about. Exploring the city or going for a hike is easier when the air isn’t so heavy.
In November, the lower humidity and cooler temps combine for some of the most comfortable conditions of the year. You’ll get clearer skies, drier air, and less need to duck into the shade or take lots of breaks. This time of year is a favorite for travelers because the climate just feels right.
Wind Speed and Atmospheric Conditions
In fall, Chiang Mai’s winds stay light and steady, and the air loses a lot of its humidity compared to the peak rainy season. These changes really shape how comfortable the weather feels.
Typical Wind Patterns in Fall
In September, October, and November, Chiang Mai usually sees low average wind speeds, often just 1–2 miles per hour. That’s calmer than the breezier months earlier in the year.
Winds shift direction, too. September brings moist southwest flows, but by late November, you’ll get drier breezes from the northeast. This comes as the monsoon ends and cooler air moves in from the continent.
Because the winds stay weak, you won’t notice strong gusts or much of a breeze. The calm air keeps temperatures steady and weather predictable. That’s great for travelers—no sudden changes in comfort when you step outside.
Effect of Wind on Weather Experience
Light winds in fall shape how you feel Chiang Mai’s climate. With such low speeds, the air doesn’t cool you down much, especially in September when highs still hit the upper 80s °F. You might feel warmer than the numbers suggest just because there’s no breeze.
By October and November, lower humidity and cool nights make up for the calm wind. The still air also means less dust blowing around, so air quality feels more stable than in the dry season, when strong winds kick up particles.
If you’re walking through markets or visiting temples, the mild wind helps keep things relaxed. You can expect a steady outdoor environment, free from sudden gusts. This makes fall a pretty easy time for sightseeing.
Travel Tips for Visiting Chiang Mai in Fall
Chiang Mai in fall brings cooler evenings, scattered showers, and fewer crowds than the peak season. You’ll find outdoor activities a lot more comfortable, though it’s smart to pack for sudden changes in weather.
Best Activities for Fall Weather
Take advantage of the mild afternoons by exploring temples and the old city on foot. The cooler weather makes walking tours and cycling so much more enjoyable than in the hot season.
Nature trips are a real treat now. Doi Suthep-Pui National Park offers hiking trails with clear views after the rains wash away the haze. Waterfalls like Mae Sa and Bua Thong often run stronger in fall, so they’re worth checking out.
Cultural events ramp up, too. In November, the Yi Peng and Loy Krathong lantern festivals light up the city. These draw big crowds but give you a special look at local traditions.
Markets like the Sunday Walking Street stay lively, and with lower humidity, browsing stalls and sampling street food is just easier. If you like quieter experiences, you can head to smaller villages outside the city for handicraft workshops and less crowded cultural shows.
Packing Recommendations
Pack light, breathable clothes for those warm afternoons. Toss in a light jacket or a sweater too, since evenings can get surprisingly cool.
At night, especially up in places like Doi Inthanon, temperatures often drop. You’ll probably appreciate having that extra layer.
Don’t forget a compact umbrella or a lightweight rain jacket. Those quick afternoon showers like to show up uninvited.
Grab quick-dry clothes and comfy shoes if you’re planning to wander outdoors or maybe trek around the hills. It just makes life easier.
I’d suggest packing insect repellent, since mosquitoes seem to love the rain almost as much as we do. A small daypack comes in handy for water, snacks, and an extra layer while you bounce between city sights and nature spots.
If you’re thinking about checking out festivals, remember to bring modest clothes that cover your shoulders and knees, especially for temple visits. And honestly, a reusable water bottle is a lifesaver if you’re out all day for events or sightseeing.