Laos is the easiest country on our route to plan, because the whole country runs on the same rhythm. From November to February it is dry, sunny and pleasant, with temperatures between twenty and thirty degrees. After that it gets hot, and from June to October it rains.
That is the short version, and for most travellers it is enough. But there are two things you need to know beforehand, and they pull in opposite directions. In spring there is smoke from the crop fires hanging over the north, and that is the one stretch of the year where we say: pick another month. And in the rainy season the waterfalls are at their best, which is exactly why some travellers come then on purpose.
Below you see what each part of the year gives you, what it means for the two motorbike loops and the slow boat, and when each place is at its best.
November to February: the best months
This is the dry season and it is good everywhere in the country. In Luang Prabang it is dry and clear with cool mornings and mist over the river, in Vientiane dry and pleasant, and in Vang Vieng and Nong Khiaw the mist sits in the valley in the morning and then lifts. In the south, around Pakse and Don Det, it is dry at around thirty degrees and sandbanks appear between the islands.
For the two motorbike loops these are the ideal months: dry roads and clear views on the Thakhek Loop from November to March, and dry roads on the Bolaven Plateau from November to February, where the altitude makes it noticeably cooler. And for the slow boat from Huay Xai, the Mekong is at a good level.
Do bring warm layers for the mornings and evenings, because in the mountains and up on the plateau it cools down a lot.
Our verdict: come between November and February if you only get one shot, because that is when everything works
March to May: hot, and smoke in the north
These are the hottest months, with temperatures above thirty-five degrees in Vientiane, Pakse, Huay Xai and Don Det, and in Thakhek in April and May. Start early, plan your afternoons indoors and drink more than you think you need.
There is one thing that matters more than the heat. In March and April it is burning season in Luang Prabang, and around Huay Xai, Nong Khiaw and Vang Vieng the haze often hangs on into May: the smoke from the crop fires sits in the valleys, the views over the mountains disappear and the air quality is bad. In Nong Khiaw the climb to the viewpoints then ends on a grey view, and on the Mekong at Huay Xai you can barely see the far bank. If you want to see the north, plan it for another part of the year.
Two things do make up for this stretch. Pi Mai, Lao New Year, falls in April, and it is a water festival the whole country joins in. And on Don Det the river is at its lowest, which gives you the best chance of the year of seeing the dolphins. There are only a handful left, so a fin in the distance counts as a good morning.
Our verdict: save the north for the dry or the rainy season, and head south for Pi Mai or the dolphins
June to October: rainy season, and the best waterfalls
The rain comes in short but heavy showers, usually in the afternoon, and in between it is simply dry. The landscape is at its greenest, prices are at their lowest and the popular places are noticeably quiet. In Luang Prabang the rainy season starts a month earlier, in May.
And then the waterfalls. Kuang Si near Luang Prabang is at its most powerful, on the Bolaven Plateau the falls properly thunder, and near Don Det, Khone Phapheng is overwhelming in these months. If you are coming for the water, come in the rainy season. The best compromise is the end of it, September and October: the waterfalls are still full but the roads are already easier to ride.
What you give up for it: on the Thakhek Loop some sections become impassable, and the boat trip through the Kong Lor cave can be suspended when the water is high. In Nong Khiaw the paths to the peaks get slippery, and in Vang Vieng the river runs high and fast, which can shut tubing down for a while.
Our verdict: come in September or October if you want the waterfalls without doing the whole country in the mud
How hot is it really?
The numbers help with packing. In the dry season the average daytime temperature is around twenty-eight to thirty-one degrees: twenty-eight in Luang Prabang and Nong Khiaw, twenty-nine in Vientiane and Vang Vieng, thirty in Thakhek and Pakse, and thirty-one on Don Det. So the south is consistently a few degrees warmer than the north.
In the hottest months that climbs to between thirty-four and thirty-six degrees, and on the Bolaven Plateau, at well over a thousand metres, it stays noticeably cooler. In the rainy season it drops back to around thirty-one.
What catches people out is the night. In the dry season the mountains and the plateau cool down a lot, and on a scooter early in the morning that is the difference between loving it and shivering. Pack a jumper and a windproof jacket, even if you are packing for a tropical country.
Our verdict: pack warm layers for the dry season, because the mornings in the mountains are colder than anyone expects
Place by place: when is each one at its best?
- Luang Prabang, Vientiane, Huay Xai, Pakse and Don Det: November to February
- Vang Vieng and Thakhek: November to March
- Nong Khiaw: October to March
The range is small, and that is what makes Laos easy. Come in the dry season and you can build your route entirely around what you want to do rather than around the weather.
What it means for the loops and the slow boat
The three things people come to Laos for all depend on the weather, so plan those first and fit the rest around them.
The Thakhek Loop is best ridden from November to March. In the rainy season it is only for experienced riders who have checked which sections are passable, and even then the cave may be closed. The Bolaven Loop is most comfortable to ride from November to February, but at its most beautiful to look at in September and October. And the slow boat from Huay Xai to Luang Prabang is at its most pleasant when the Mekong is at a good level, from November to February.
The whole route and its connections are in our Laos itinerary and in our guide to getting around Laos. The loops themselves are on our pages for Thakhek and Pakse, the two towns they start from.
Picked your month? The rest is on our Laos page: the eight stops along the Mekong, with where to sleep and what a day costs at each one.
What is the worst month to visit Laos?
April, if you are heading north. It is right in the hottest stretch of the year, with temperatures above thirty-five degrees, and it is also the second month of the burning season, so the smoke hangs in the valleys around Luang Prabang, Nong Khiaw and Huay Xai. The mountains you came to look at are simply not there.
There is one reason to go anyway: Pi Mai, Lao New Year, falls in April and it is one of the most fun festivals in Southeast Asia. If that is why you are coming, stay in the south or accept that the view is a side issue for those few days.
And if you are coming in July or August, that is not a bad choice, just a different trip: greener, wetter, cheaper and with the waterfalls at their strongest. Only the motorbike loops get harder.
