This report describes the typical weather at the Don Muang International Airport (Old Bangkok International Airport) (Bangkok, Thailand) weather station over the course of an average year. It is based on the historical records from 1974 to 2011. Earlier records are either unavailable or unreliable.
Bangkok has a tropical savanna climate with dry winters. The area within 25 mi of this station is covered by croplands (85%), shrublands (9%), and built-up areas (5%).
Over the course of a year, the temperature typically varies from 70Â°F to 96Â°F and is rarely below 65Â°F or above 100Â°F.
The warm season lasts from March 20 to May 8 with an average daily high temperature above 94Â°F. The hottest day of the year is April 13, with an average high of 96Â°F and low of 79Â°F.
The cold season lasts from October 25 to January 15 with an average daily high temperature below 89Â°F. The coldest day of the year is December 25, with an average low of 70Â°F and high of 88Â°F.
The length of the day does not vary substantially over the course of the year, staying within 50 minutes of 12 hours throughout. The shortest day is December 21 with 11:11 hours of sunlight; the longest day is June 20 with 12:50 hours of sunlight.
The earliest sunrise is at 5:53am on May 24 and the latest sunrise is at 6:50am on January 19. The earliest sunset is at 5:43pm on November 12 and the latest sunset is at 6:46pm on June 29.
Daylight savings time (DST) is not observed in 2012.
The median cloud cover ranges from partly cloudy (49%) to mostly cloudy (90%). The sky is cloudiest on June 28 and clearest on January 2. The clearer part of the year begins around November 7. The cloudier part of the year begins around April 14.
On January 2, the clearest day of the year, the sky is clear, mostly clear, or partly cloudy 73% of the time, and overcast or mostly cloudy 17% of the time.
On June 28, the cloudiest day of the year, the sky is overcast, mostly cloudy, or partly cloudy 95% of the time, and clear or mostly clear 1% of the time.
The probability that precipitation will be observed at this location varies throughout the year. Precipitation is most likely around September 3, occurring in 77% of days. Precipitation is least likely around December 20, occurring in 8% of days.
Over the entire year, the most common forms of precipitation are thunderstorms, moderate rain, and light rain.
Thunderstorms are the most severe precipitation observed during 47% of those days with precipitation. They are most likely around September 21, when it is observed during 38% of all days.
Moderate rain is the most severe precipitation observed during 29% of those days with precipitation. It is most likely around August 14, when it is observed during 27% of all days.
Light rain is the most severe precipitation observed during 23% of those days with precipitation. It is most likely around August 16, when it is observed during 20% of all days.
During the warm season, which lasts from March 20 to May 8, there is a 33% average chance that precipitation will be observed at some point during a given day. When precipitation does occur it is most often in the form of thunderstorms (62% of days with precipitation have at worst thunderstorms), light rain (19%), and moderate rain (17%).
During the cold season, which lasts from October 25 to January 15, there is a 18% average chance that precipitation will be observed at some point during a given day. When precipitation does occur it is most often in the form of thunderstorms (39% of days with precipitation have at worst thunderstorms), moderate rain (31%), and light rain (27%).
Either snow is exceptionally unlikely to fall at any time during the year at this location or this station does not reliably report precipitation types.
The relative humidity typically ranges from 44% (comfortable) to 94% (very humid) over the course of the year, rarely dropping below 32% (comfortable) and reaching as high as 100% (very humid).
The air is driest around January 1, at which time the relative humidity drops below 50% (comfortable) three days out of four; it is most humid around September 19, exceeding 91% (very humid) three days out of four.
Dew point is often a better measure of how comfortable a person will find the weather than relative humidity because it more directly relates to whether perspiration will evaporate from the skin, thereby cooling the body. Lower dew points feel drier and higher dew points feel more humid.
Over the course of a year, the dew point typically varies from 61Â°F (comfortable) to 79Â°F (oppressive) and is rarely below 53Â°F (very comfortable) or above 83Â°F (very oppressive).
Over the course of the year typical wind speeds vary from 0 mph to 14 mph (calm to moderate breeze), rarely exceeding 21 mph (fresh breeze).
The highest average wind speed of 9 mph (gentle breeze) occurs around July 2, at which time the average daily maximum wind speed is 14 mph (moderate breeze).
The lowest average wind speed of 4 mph (light breeze) occurs around January 1, at which time the average daily maximum wind speed is 9 mph (gentle breeze).