Weather of Assam – Climate, Rainfall & Temperature

Climate 

• The climate of Assam is typically ‘tropical monsoon rainfall’ type, with high levels of humidity and heavy rainfall. A moderate climate all throughout the year, with warm
  summers and mild winters.
• Climatic variations can be seen regionally. While the plains of Assam have a tropical climate with high humidity, the hills have a sub-alpine type of climate.
• The climate of Assam is characterised by alternate cool and warm periods with a highly humidity, especially from May to November. Between March and May at the time when precipitation in Northern India is at the minimum, Assam gets some amount of rainfall from the Norwesters which keep the temperature low in the season of spring.
• In the plains of Assam, the maximum temperature does not go beyond 90oF.or 32oC and in winter the plains of Assam have a minimum temperature of about 8oC. The climate of the plains and the sub-montane region becomes unpleasant, especially in the summer season. It happens to be so because of the extreme humidity which comes with the monsoon.
• There are four distinct seasons in Assam - summer, monsoon, autumn and winter.

Summers

• The summer season in Assam starts from the month of March and extends till the end of June. The season is characterized by extreme humidity and frequent showers.
• The average temperature during this time of the year is between 35 and 38 degree Celsius. In fact, the mercury level never rises more than 38 degrees, even in the hottest month of the year.

Monsoons

• This season brings relief from the scorching heat of the summers. The neighboring areas of Cherapunji and Mawsynram have the highest rainfall in the world. The average annual rainfall in the state is around 70 inches in the west and around 120 inches in the east.
• In the afternoons, thunderstorms known as Bordoicila are very common. The season covers the entire state with a green blanket.

Winters

• The winter season in Assam is basically characterized by scanty rainfall and misty mornings and afternoons. It starts in November and continues till the month of February.
• The mercury reading at this time of the year is around 6 to 8 degree Celsius or 43- 46 degree Fahrenheit.

Spring & Autumn

• In Assam, spring (March- April) and autumn (September- October) present pleasant seasons, with moderate temperature and rainfall. These are amongst the popular months for tourist rush.

RAINFALL

• Assam receives typical monsoon rains. The south-west monsoon rains starts from the third week of June and they continue up to the middle of September. The State receives during this period about 180 cm of rainfall on the average.
• This constitutes about 80% of the average rainfall of the State while the remaining 20% come in the form of occasional rains in January (as a result of the extension of the westerlies that come to the north-western India causing rainfall in Panjab, Haryana and western Uttar Pradesh and snowfall in Jammu and Kashmir, Himachal and the Himalayan region and in March-April (nor'westers or Bordoichila).
• There is however, religion variation in the rainfall pattern. It is found that as the Maghalaya Plateau stands on the way of the main branch of the rain - bearing south-west monsoon winds, the southern portion of the Brahmaputra Plains skirting the Plateau fall in the rainshadow zone.
• Hence the south-eastern part of Kamrup district from Guwahati eastward. Southern part of Nagaon district .northern part of Hamren subdivision and the eastern foothills of Karbi -Rengma hills receive less rainfall than the other parts of the Brahmaputra Plains.
• In fact, the Lanka-Lumding receives hardly 100 cm of average annual rainfall. Similarly, the Diphu-Nambar region also receives a small quantity of rain. In other parts of the Bhrahmaputra Plains, rainfall increases as one goes to the east or north or west.
• The heaviest rainfall exceeding 200 cm is received in Tinsukia, Dibrugarh, Dhemaji and Lakhimpur districts and along the Himalayan foothill region. The average annual rainfall is around 200cm all over the middle part of the Brahmaputra Valley from the east to the west.
• While the western part Of Karbi Anglong receives 200cm of average annual rainfall. North Cachar Hills and the Barak plains receive more than 200cm.