The best times to visit Lang Son for ideal weather are

October 8th to April 15th

based on average temperature and humidity from NOAA (the National Oceanic and Atmospheric Administration). Read below for more weather and travel details.



Other Lang Son Travel Info

Weather in Lang Son


Average temperatures in Lang Son vary greatly. Considering humidity, temperatures feel hot for about half of the year and otherwise nice with a fair chance of precipitation about half of the year. The area is somewhat temperate — in the 45th percentile for pleasant weather — compared to tourist destinations worldwide. Weeks with ideal weather are listed above. If you’re looking for the very warmest time to visit Lang Son, the hottest months are July, June, and then August. See average monthly temperatures below. The warmest time of year is generally early to mid July where highs are regularly around 91.3°F (32.9°C) with temperatures rarely dropping below 75.5°F (24.2°C) at night.

Lang Son Temperatures (Fahrenheit)


Lang Son Temperatures (Celsius)


“Feels-Like” Temperatures

The way we experience weather isn’t all about temperature. Higher temperatures affect us much more at higher humidity, and colder temperatures feel piercing with high winds. Our perceived temperatures factor in humidity and wind chill to better represent how hot or cold the day feels to a person.

Lang Son Perceived Temperature (F)


Lang Son Perceived Temperature (C)



Average Lang Son Temperatures by Month

Daily highs (averaged for the month) usually give the best indication of the weather. A significantly lower mean and low generally just means it gets colder at night.

Show Fahrenheit

Month Avg. High (°F) Avg. Mean (°F) Avg. Low (°F)
Jan 60.7 54.1 47.9
Feb 67.8 61 54.8
Mar 71.1 65.2 59.9
Apr 79.5 72.6 66.3
May 86.7 78.6 71.9
Jun 89.1 81.2 74.9
Jul 89.5 81.2 75.1
Aug 88.7 80.2 74.5
Sep 85.9 77.9 72.1
Oct 81.6 73.2 66.2
Nov 74.9 66 58.6
Dec 65.8 58.2 51.3

Show Celsius

Month Avg. High (°C) Avg. Mean (°C) Avg. Low (°C)
Jan 15.9 12.3 8.8
Feb 19.9 16.1 12.7
Mar 21.7 18.4 15.5
Apr 26.4 22.6 19.1
May 30.4 25.9 22.2
Jun 31.7 27.3 23.8
Jul 31.9 27.3 23.9
Aug 31.5 26.8 23.6
Sep 29.9 25.5 22.3
Oct 27.6 22.9 19
Nov 23.8 18.9 14.8
Dec 18.8 14.6 10.7



Precipitation (Rain or Snow)

If dry weather is what you’re after, the months with the lowest chance of significant precipitation in Lang Son are January, February, and then December. Note that we define “significant precipitation” as .1 inches or more in this section. The lowest chance of rain or snow occurs around early February. For example, on the week of February 5th there are no days of precipitation on average. By contrast, it’s most likely to rain or snow in late July with an average of 4 days of significant precipitation the week of July 23rd.

When can you find snow in Lang Son? Weather stations report no annual snow. Please note that a value of 0 for snow in the graph below may either mean there was no snow, or that snow is unreported.

Chance of Precipitation

The graph below shows the % chance of rainy and snowy days in Lang Son.

Days with precipitation

Snow on the Ground

The graph below shows the average snow on the ground in Lang Son (in).

Snow depth

Average Rain and Snow by Month

Show Inches

Month Daily Chance of Rain Average Snow Depth (in) Total Precipitation (in)
Jan 6% 0 1.3
Feb 7% 0 0.8
Mar 12% 0 1.9
Apr 16% 0 3.3
May 28% 0 5.2
Jun 35% 0 7.2
Jul 38% 0 9.8
Aug 35% 0 8.6
Sep 28% 0 8.5
Oct 12% 0 2.2
Nov 12% 0 2.6
Dec 11% 0 1.6

Show Centimeters

Month Daily Chance of Rain Average Snow Depth (cm) Total Precipitation (cm)
Jan 6 0 3.3
Feb 7 0 2
Mar 12 0 4.8
Apr 16 0 8.4
May 28 0 13.2
Jun 35 0 18.3
Jul 38 0 24.9
Aug 35 0 21.8
Sep 28 0 21.6
Oct 12 0 5.6
Nov 12 0 6.6
Dec 11 0 4.1


Humidity and Wind

Lang Son has some extremely humid months, and high humidity throughout the year. The least humid month is December (70.3% relative humidity), and the most humid month is August (81.5%).

Wind in Lang Son is usually extremely calm. The windiest month is January, followed by December and February. January’s average wind speed of around 4.8 knots (5.5 MPH or 8.9 KPH) is considered “a light breeze.” Maximum sustained winds (the highest speed for the day lasting more than a few moments) are at their highest in late January where average top sustained speeds reach 8.9 knots, which is considered a gentle breeze.

Relative Humidity (%)

The graph below shows the average % humidity by month in Lang Son.

Avg. Relative Humidity


The graph below shows wind speed (max and average) in knots.

Max Sustained Wind
Average Daily Wind

Average Wind Speeds

Show Wind Speeds

All wind speeds are in knots. 1 knot = 1.15 MPH or 1.85 KPH.

Month Avg. Wind Avg. Wind Feel Sustained High Wind High Wind Feel
Jan 4.8 Light breeze 8.3 Gentle breeze
Feb 3.9 Barely noticeable 7.4 Gentle breeze
Mar 3.7 Barely noticeable 7.2 Gentle breeze
Apr 3.5 Barely noticeable 6.8 Light breeze
May 3.1 Barely noticeable 6.3 Gentle breeze
Jun 2.5 Barely noticeable 5.8 Light breeze
Jul 2.4 Barely noticeable 5.6 Gentle breeze
Aug 2.1 Barely noticeable 5.4 Light breeze
Sep 2.7 Barely noticeable 6.1 Gentle breeze
Oct 3.1 Barely noticeable 6.6 Light breeze
Nov 3.6 Barely noticeable 7.4 Gentle breeze
Dec 4.1 Light breeze 7.7 Gentle breeze

Show Relative Humidity by Month

Month Avg. Relative Humidity
Jan 72.9%
Feb 75%
Mar 78.8%
Apr 76.7%
May 76.4%
Jun 79.6%
Jul 79.6%
Aug 81.5%
Sep 80.8%
Oct 75.4%
Nov 72.7%
Dec 70.3%


Is it Safe to Travel to Lang Son?

Our best data indicates this area is somewhat safe. As of Oct 07, 2019 there are travel warnings for Vietnam; exercise a high degree of caution. Check this page for any recent changes or regions to avoid: Travel Advice and Advisories. This advisory was last updated on Aug 22, 2019.


The Busiest and Least Crowded Months

The busiest month for tourism in Lang Son, Vietnam is October, followed by January and June. Prices for hotels and flights will be most expensive during these months, though you can save if you purchase well in advance. Tourists are unlikely to visit Lang Son in February. Those willing to visit at these times will likely find it the least expensive month.

Estimated Tourism by Month


Most Popular Months to Visit

Tourists Seeking Accommodations

Tourism graph is based on Google searches for services used by tourists relative to the rest of the year. Tourism data for this area is extrapolated based on nearby areas. Displayed data is calculated relative to the peak, so a score of 57.2 in February means 57.2% of the tourists vs. October.



Overall Lang Son Travel Experience by Season

Spring (March through May)

Humidity and temperatures combine to make this season feel warm. Highs range from 88.3°F (31.3°C) and 65.4°F (18.6°C) with warmer temperatures in the later months. Rain is somewhat common with 4 to 9 days of significant precipitation per month. Spring is the slowest for tourism, which makes it a good time for those looking for deals.

Summer (June through August)

The middle-year months have very comfortable weather with high temperatures that are quite warm. These months see the most precipitation with 11 to 12 days of precipitation per month. June – August is the second busiest season for tourism in Lang Son, so lodging and other accommodations may cost slightly more.

Fall (September through November)

Fall daily highs range from 86.9°F (30.5°C) and 71.4°F (21.9°C), which will feel very nice given the humidity and wind. It rains or snows a significant amount: 4 to 8 days per month. Tourism is the busiest during these months due to the weather, so hotels may be higher priced.

Winter (December through February)

Weather is somewhat cool this time of year in Lang Son to be enjoyable for warm weather travelers. The average high during this season is between 70.3°F (21.3°C) and 59.1°F (15.1°C). On average, it rains or snows a smalll amount: 2 to 3 times per month. These times of year are fairly slow with tourists.


Best Times to TravelVietnam › Lang Son, Vietnam