Average Weather in Chiang Mai Thailand
In Chiang Mai, the wet season is oppressive and overcast, the dry season is mostly clear, and it is hot year round. Over the course of the year, the temperature typically varies from 59°F to 97°F and is rarely below 53°F or above 102°F.
The hot season lasts for 1.9 months, from March 11 to May 8, with an average daily high temperature above 94°F. The hottest day of the year is April 13, with an average high of 97°F and low of 74°F.
The cool season lasts for 2.3 months, from November 17 to January 25, with an average daily high temperature below 86°F. The coldest day of the year is January 8, with an average low of 59°F and high of 84°F.
Average High and Low Temperature
The figure below shows you a compact characterization of the entire year of hourly average temperatures. The horizontal axis is the day of the year, the vertical axis is the hour of the day, and the color is the average temperature for that hour and day.
Average Hourly Temperature
In Chiang Mai, the average percentage of the sky covered by clouds experiences extreme seasonal variation over the course of the year.
The clearer part of the year in Chiang Mai begins around October 27 and lasts for 5.7 months, ending around April 19. On February 20, the clearest day of the year, the sky is clear, mostly clear, or partly cloudy 75% of the time, and overcast or mostly cloudy 25% of the time.
The cloudier part of the year begins around April 19 and lasts for 6.3 months, ending around October 27. On August 2, the cloudiest day of the year, the sky is overcast or mostly cloudy 93% of the time, and clear, mostly clear, or partly cloudy 7% of the time.
A wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. The chance of wet days in Chiang Mai varies very significantly throughout the year.
The wetter season lasts 5.8 months, from April 25 to October 18, with a greater than 31% chance of a given day being a wet day. The chance of a wet day peaks at 61% on September 3.
The drier season lasts 6.2 months, from October 18 to April 25. The smallest chance of a wet day is 2% on January 12.
Among wet days, we distinguish between those that experience rain alone, snow alone, or a mixture of the two. Based on this categorization, the most common form of precipitation throughout the year is rain alone, with a peak probability of 61% on September 3.
Daily Chance of Precipitation
To show variation within the months and not just the monthly totals, we show the rainfall accumulated over a sliding 31-day period centered around each day of the year. Chiang Mai experiences extreme seasonal variation in monthly rainfall.
The rainy period of the year lasts for 8.9 months, from March 9 to December 6, with a sliding 31-day rainfall of at least 0.5 inches. The most rain falls during the 31 days centered around September 4, with an average total accumulation of 7.7 inches.
The rainless period of the year lasts for 3.1 months, from December 6 to March 9. The least rain falls around February 5, with an average total accumulation of 0.2 inches.
Average Monthly Rainfall
The length of the day in Chiang Mai varies over the course of the year. In 2017, the shortest day is December 21, with 11 hours, 0 minutes of daylight; the longest day is June 21, with 13 hours, 16 minutes of daylight.
Hours of Daylight and Twilight
The earliest sunrise is at 5:46 AM on June 5, and the latest sunrise is 1 hour, 14 minutes later at 6:59 AM on January 18. The earliest sunset is at 5:45 PM on November 25, and the latest sunset is 1 hour, 20 minutes later at 7:05 PM on July 6.
Daylight saving time (DST) is not observed in Chiang Mai during 2017.
Sunrise & Sunset with Twilight
We base the humidity comfort level on the dew point, as it determines whether perspiration will evaporate from the skin, thereby cooling the body. Lower dew points feel drier and higher dew points feel more humid. Unlike temperature, which typically varies significantly between night and day, dew point tends to change more slowly, so while the temperature may drop at night, a muggy day is typically followed by a muggy night.
Chiang Mai experiences extreme seasonal variation in the perceived humidity.
The muggier period of the year lasts for 8.3 months, from March 30 to December 7, during which time the comfort level is muggy, oppressive, or miserable at least 27% of the time. The muggiest day of the year is August 12, with muggy conditions 94% of the time.
The least muggy day of the year is January 6, with muggy conditions 4% of the time.
Humidity Comfort Levels
This section discusses the wide-area hourly average wind vector (speed and direction) at 10 meters above the ground. The wind experienced at any given location is highly dependent on local topography and other factors, and instantaneous wind speed and direction vary more widely than hourly averages.The average hourly wind speed in Chiang Mai does not vary significantly over the course of the year, remaining within 0.2 miles per hour of 1.4 miles per hour throughout.
Average Wind Speed
The predominant average hourly wind direction in Chiang Mai varies throughout the year.
The wind is most often from the south for 1.1 weeks, from January 14 to January 22; for 1.5 months, from May 7 to June 21; and for 1.3 weeks, from September 12 to September 21, with a peak percentage of 56% on May 30. The wind is most often from the west for 3.5 months, from January 22 to May 7 and for 2.7 months, from June 21 to September 12, with a peak percentage of 57% on March 27. The wind is most often from the east for 3.8 months, from September 21 to January 14, with a peak percentage of 40% on January 1.
This section discusses the total daily incident shortwave solar energy reaching the surface of the ground over a wide area, taking full account of seasonal variations in the length of the day, the elevation of the Sun above the horizon, and absorption by clouds and other atmospheric constituents. Shortwave radiation includes visible light and ultraviolet radiation.
The average daily incident shortwave solar energy experiences some seasonal variation over the course of the year.
The brighter period of the year lasts for 2.1 months, from February 20 to April 24, with an average daily incident shortwave energy per square meter above 6.0 kWh. The brightest day of the year is March 27, with an average of 6.4 kWh.
The darker period of the year lasts for 2.6 months, from July 6 to September 23, with an average daily incident shortwave energy per square meter below 4.9 kWh. The darkest day of the year is August 26, with an average of 4.5 kWh.
Average Daily Incident Shortwave Solar Energy
For the purposes of this report, the geographical coordinates of Chiang Mai are 18.790 deg latitude, 98.985 deg longitude, and 1,017 ft elevation.
The topography within 2 miles of Chiang Mai contains only modest variations in elevation, with a maximum elevation change of 148 feet and an average elevation above sea level of 1,027 feet. Within 10 miles contains only modest variations in elevation (4,573 feet). Within 50 miles also contains extreme variations in elevation (7,723 feet).
The area within 2 miles of Chiang Mai is covered by artificial surfaces (95%), within 10 miles by cropland (59%) and trees (26%), and within 50 miles by trees (78%) and cropland (19%).
This report illustrates the typical weather in Chiang Mai, based on a statistical analysis of historical hourly weather reports and model reconstructions from January 1, 1980 to December 31, 2016.
Temperature and Dew Point
There are 2 weather stations near enough to contribute to our estimation of the temperature and dew point in Chiang Mai.
For each station, the records are corrected for the elevation difference between that station and Chiang Mai according to the International Standard Atmosphere , and by the relative change present in the MERRA-2 satellite-era reanalysis between the two locations.
The estimated value at Chiang Mai is computed as the weighted average of the individual contributions from each station, with weights proportional to the inverse of the distance between Chiang Mai and a given station.
All data relating to the Sun's position (e.g., sunrise and sunset) are computed using astronomical formulas from the book, Astronomical Tables of the Sun, Moon and Planets , by Jean Meeus.
All other weather data, including cloud cover, precipitation, wind speed and direction, and solar flux, come from NASA's MERRA-2 Modern-Era Retrospective Analysis . This reanalysis combines a variety of wide-area measurements in a state-of-the-art global meteorological model to reconstruct the hourly history of weather throughout the world on a 50-kilometer grid.
Land Use data comes from the Global Land Cover SHARE database , published by the Food and Agriculture Organization of the United Nations.
Elevation data comes from the Shuttle Radar Topography Mission (SRTM) , published by NASA's Jet Propulsion Laboratory.
Names, locations, and time zones of places and some airports come from the GeoNames Geographical Database .
Time zones for aiports and weather stations are provided by AskGeo.com .
Maps are © Esri, with data from National Geographic, Esri, DeLorme, NAVTEQ, UNEP-WCMC, USGS, NASA, ESA, METI, NRCAN, GEBCO, NOAA, and iPC.