Thailand’s capital city draws an estimated 45 million tourists yearly and several travel publications have deemed it one of the world’s best cities. It’s easy to see why travelers would gravitate there, with its colorful patchwork of Buddhist temples and ultra-modern hotels, gleaming taxis and three-wheeled tuk-tuks. Though Bangkok is a year-round destination, its flood-inducing monsoons, tourist droves and traditional festivals are important considerations.
Bangkok is always hot, though not always sunny. Temperatures average over 30°C throughout the year and the Thai capital experiences heavy humidity for much of it. However, the heat is at its worst during April and the monsoons their peak during October, so avoid these two periods, as they are the very worst. The best time to visit Bangkok is from late October to Feb.
There are 3 seasons with sunny days throughout most of the year in Bangkok. From late May to October rainy season begins. During this time weather is warm and humid and most days have few showers. But If you are travelling this time, don’t try to bring a raincoat because it will be too hot to wear it. Just carry an Umbrella at all time on any area of Bangkok and, you will be fine.
The best time of Bangkok is from late October to Feb. This is cool season but you need not to bring warm clothes it means you sweat a little less.
The worst time you do not want to travel from March to May. During this time the Weather is hot, hot, hot.
Here is a link to the latest information about Bangkok – Five Day Forecast